Agronomy

Potato virus Y (PVY) affects both yield and the quality of the crop, making it one of the most dangerous diseases faced by commercial potato producers. Spread by aphids and through infected seed lots, PVY has been managed with varying levels of success by Canadian growers for many years, but the rise of more aggressive and faster-spreading strains has made it even more challenging to control.
Potato industry stakeholders from across the United States gathered in Bangor, Maine in November 2017 to deliberate on Dickeya, the aggressive disease that’s devastated thousands of potato acres in the U.S. since its first major outbreak in 2015.
As spring arrives, potato growers are concerned about Dickeya, and Eugenia Banks, the Ontario potato specialist, has some points of interest to share. Potato seed infected late in the season with Dickeya (new blackleg) usually does not show symptoms in the field before harvest nor in seed storages. This is because Dickeya requires high temperatures for the development of visible symptoms. The optimum temperature for Dickeya is above 25 C. By contrast, the old blackleg (Pectobacterium) can develop at cool temperatures (8 C to 10 C), and symptoms are usually visible when cutting seed.Banks says she received two questions about Dickeya: Q: If dormant infection of Dickeya is suspected, could you incubate a sample of tubers at 25 C to 30 C so the tubers will show Dickeya symptoms in about 2 weeks? A: Banks asked Steve Johnson (Maine) and Gary Secor (North Dakota) this question and both said no. It takes more than two weeks for the symptoms to develop. Banks says the first time she saw Dickeya symptoms developing from seed tubers with dormant infection was in late June (the seed tubers had been planted by the middle of May), and both Johnson and Secor agree. Q: Are Dickeya lesions smelly? A: We all know how smelly the old blackleg is. The slimy, black stems smell like rotten fish, a disgusting smell noticeable at least 30 feet away from an infected plant. Usually Dickeya is not smelly. The bacterium grows inside the stem moving up in the vascular tissue. Dickeya-infected stems are usually dark brown, not inky black, slimy and smelly like the old blackleg. Eventually, the infected stems may be invaded by secondary bacteria that cause a black rot. If, shortly after emergence, you see small, wilted plants with a black stem base, it is probably the old blackleg. If the summer is cool and wet, probably the old blackleg will prevail. In hot summers, Dickeya will be the prevalent disease (wilted foliage is also a symptom of Dickeya).
Syngenta Canada Inc. has announced Orondis Ultra fungicide is now available in a premix formulation for added convenience.
For the first time, evidence of the zebra chip pathogen has been found in potato fields in southern Alberta.An infected potato psyllid insect carries the Lso (Candidatus Liberibacter solanacearum) pathogen that can cause zebra chip disease in potato crops.Zebra chip has affected potato crops in the U.S., Mexico and New Zealand and caused millions of dollars in losses. Potatoes with zebra chip develop unsightly dark lines when fried, making affected potatoes unsellable.The first detection of Lso came from sampling cards collected at one site south of Highway 3, near Lethbridge, Alta. For the full story, click here. 
All the isolates of late blight -Phytophthora infestans tested were US-23 for 2017. No new late blight incidence has been reported in the last week, which has generally been dry, warm and windy. The 7-day DSV accumulation for late blight risk has been essentially minimal. Harvest has begun in many areas.The warm conditions has slowed the harvest of some processing fields, to prevent bringing warm tubers into storage. The seasonal accumulated precipitation has been 50-70% of normal in the potato growing areas (Fig1). The soils are generally on the dry side (Fig 2), but irrigated fields have sufficient moisture for a good harvest. READ MORE
The potato person who said many years ago "A potato storage is not a hospital" was absolutely right. Diseased or bruised tubers do not get better in storage. Tubers bruised at harvest are easily invaded by soft rot or Fusarium dry rot, which can cause serious economic losses in storage.Harvest management, in large part, is bruise management. Bruising also affects tuber quality significantly. In order to harvest potatoes with minimum tuber damage, growers need to implement digging, handling and storage management practices that maintain the crop quality for as long as possible after harvest.Assuming all harvest and handling equipment are mechanically ready to harvest the crop with minimum bruising, there are several tips to preserve the quality of potatoes crop during harvest: Timely Vine Killing. Killing the vines when tubers are mature makes harvesting easier by reducing the total vine mass moving through the harvester. This allows an easier separation of tubers from vines. Timely Harvest. Potatoes intended for long term storage should not be harvested until the vines have been dead for at least 14 days to allow for full skin set to occur. Soil Moisture. Optimal harvest conditions are at 60-65% available soil moisture. Tuber Pulp Temperature. Optimal pulp temperatures for harvest are from 500F to 600F. Proper pulp temperature is critical; tubers are very sensitive to bruising when the pulp temperature is below 450F. If pulp temperatures are above 650F, tubers become very susceptible to soft rot and Pythium leak. Pulp temperatures above 70°F increase the risk of pink rot tremendously no matter how gently you handle the tubers if there is inoculum in the soil. Tuber Hydration. An intermediate level of tuber hydration results in the least bruising. Overhydrated tubers dug from wet soil are highly sensitive to shatter bruising especially when the pulp temperature is below 450F. In addition, tubers harvested from cold, wet soil are more difficult to cure and more prone to breakdown in storage. Slightly dehydrated tubers dug from dry soil are highly sensitive to blackspot bruising. Reducing Blackspot Bruising. Irrigate soil that is excessively dry before digging to prevent tuber dehydration and blackspot bruising. Bruise Detection Devices. Try to keep the volume of soil and tubers moving through the digger at capacity at all points of the machine. If bruising is noticeable, use a bruise detection device to determine where in the machinery the tubers are being bruised. Do not harvest potatoes from low, poorly drained areas of a field where water may have accumulated and/or dig tests have indicated the presence of tubers infected with late blight. Train all employees on how to reduce bruising. Harvester operators must be continually on the lookout for equipment problems that may be damaging tubers. Ideally, growers should implement a bruise management program that includes all aspects of potato production from planting through harvest. Harvest when day temperatures are not too warm to avoid tuber infections. Storage rots develop very rapidly at high temperatures and spread easily in storage. If potatoes are harvested at temperatures above 27o C and cool off slowly in storage, the likelihood of storage rots is increased. If warm weather is forecast, dig the crop early in the morning when it is not so warm.
Nov. 29, 2016, Canada – Canada's potato production was 105.2 million hundredweight (4.7 million tonnes) in 2016, up 0.5 per cent from 2015, according to the latest report from Statistics Canada. Production in British Columbia increased 41.8 per cent to 315 hundredweight per acre. Ontario, which experienced extreme summer heat and drought, saw production and yield fall 17.2 per cent compared with a year earlier. Harvested area edged down 0.2 per cent from 2015. In 2016, Prince Edward Island represented 24.5 per cent of total potato production and Manitoba represented 21.3 per cent.
Some P.E.I. potato farmers have had to wait longer than usual to finish their harvest because of recent wet weather, according to the P.E.I. Potato Board. | READ MORE
Ambra variety potatoes harvested by C&V Farms in October. Photo courtesy of Eugenia Banks.  Oct. 27, 2016, Ontario – Each growing season is different, but the 2016 season was unlike any season seen before in Ontario. Planting started later than usual due to the cold weather. The early crop planted by the middle of April in southwestern Ontario took more than three weeks to emerge due to cool soil temperatures. Growers were caught off guard when snow fell by the middle of May. The season was off to a bumpy start.  There was only limited rain up to the end of May. Then the heat and drought started relentlessly – too early in the season.  Studies have shown that a healthy crop of potatoes needs an inch of rain a week. That adds up to about 16 inches of rain from May through August for the potato crop to show its full potential. Environment Canada data indicates that the water deficit in Norfolk, Simcoe and Dufferin counties was above 60 per cent. Norfolk County was the hardest hit by the heat and drought, with a total rainfall close to four inches near Delhi.  Where available, irrigation was the order of the day during the summer. However, growers could not keep up with irrigation due to the extremely high evapo-transpiration rate. Irrigation increased the cost of production dramatically. By July, there were reports of some irrigation ponds that were completely empty and not filling up. One producer said, “With the heat and drought we are experiencing, irrigation is simply keeping the crop alive. Rain water does way more for the crop than irrigation.”  There were many days in June, July and August when the temperatures were above 30 C. Such heat puts the potato plants in a dormant state, unable to photosynthesize efficiently, the activity that keeps plants functioning well.  Some rainfall by the middle of August did not help the early crop, which was too far gone to benefit from rain.  Ontario Potato Distributing in Alliston started packing early potatoes from Leamington on July 19. Quality was excellent. The harvest of the early crop continued in August but yields were down at least 50 per cent in non-irrigated fields. In irrigated fields, yield reduction was at least 35 per cent.  Dry weather brings good quality. Diseases such as late blight, pink rot and leak did not develop. These diseases, also known as storage rots, reduce quality and can cause significant storage losses.  Hot, dry weather also induces second growth. A few table varieties with short dormancy aged rapidly in the field and showed some sprouting before harvest.  Mark VanOostrum reports that the chip processing crop yielded as low as 60 per cent of normal yield. The best yields were reported from the Shelburne area in the late-planted crop and late-season varieties. Harvest was difficult, because it took more than five to six weeks to get good skin set after topkill or natural death. Because the fall was very warm, storages temperatures are just starting to drop below 13 C. Typically, the temperature would have been down to 9 C on many bins for a few weeks by this time of the year. Higher storage temperatures will age the crop (one that was already aged in the field due to the heat and drought). The processing of the storage crop started earlier than anytime in recent history due to the shortage of field fry crop. Some heat necrosis was seen in Atlantics, but minimal in other varieties. So far, the quality of the storage crop has been very good. Some stem end sugar defect is present, but less than normal for this early in the storage season. One real concern is how the long-term effect of the heat and drought stress affect the chipping quality. Stem end sugar defect incidence and severity is highly correlated with extreme heat, and the question remains: will we be able to burn off all the stem end? Also, the heat and drought stress is correlated with chemical and physical aging. Will a variety that typically has a seven-month life span be shortened by weeks or months? Time will tell. By Thanksgiving, nearly all the table and processing crop had been dug and stored with no risk of storage rots.  Ontario potato growers will remember 2016 as one of the hottest and driest year in Ontario. Our potato growers should be commended for their resilience and capacity to produce a high-quality crop in what was an extremely difficult growing season.   
Oct. 21, 2016, Canada – As potato harvest wraps up, the United Potato Growers of Canada reports conditions were generally favourable for growers across the country.  Prince Edward Island Approximately 35 per cent of P.E.I.'s potato crop had been harvested by Thanksgiving. Beautiful weather has made for excellent harvest conditions. Overall quality going into storage to date has been good with the exception of some isolated issues such as scab. Size profile is a bit lower on some of the first crop dug but current projections are for at least an average yield. Demand has been very good and as a result, fresh shipments are ahead of last year at this time. P.E.I. has begun shipping into some markets at an earlier time frame than normal. Prices are much better that this time last year.  New Brunswick Excellent harvesting conditions have put the harvest percentage between 75 and 80 per cent as Oct. 7. Yields have been good with many fields in the northern region running around 375 cwt./acre and 325 to 350 cwt./acre in the southern part of the province. Fresh sheds are running product out of field to help several growers finish up. Growers and sheds seem particularly happy with the yield and quality of the Innovator variety this year, which did not seem to be as susceptible to heat and dry conditions experienced. Quebec Excellent weather had brought the harvest to between 75 and 80 per cent completion as of Oct. 7. Many growers have only a week left, although the Lac St. Jean area will probably need two weeks. Yields are status quo, but certainly down from last year’s record setter. Quality is very good, with perhaps a smaller size profile in some areas. Movement has been very good to date. Pricing is stable and packers have agreed to leave it at current price points for now. OntarioOntario’s harvest was 85 per cent complete on Oct. 7. The Shelburne area, which is usually the last planted region due to a later spring with cooler soil temperatures, is about 60 per cent harvested. Growers in the province have experienced a 50 per cent yield reduction on dry land crops and a 20 per cent reduction on irrigated fields. Dry weather however does bring good storage conditions with no storage rot, so the quality of both fresh and processing spuds, is excellent. Trials this year showed some of the standard varieties performed better in the heat and drought than some of the newer ones, which exhibited secondary growth, knobs and growth cracks. Shippers also feel, chef size and larger size sku’s should bring more of a premium this year. The Ontario fresh market has been strong without the traditional downward pressure on price experienced this time of year. Virtually all of the chip harvest was in the bin by Thanksgiving. Manitoba Manitoba’s harvest was 95 per cent complete on Oct. 7. Harvest conditions were very wet after receiving three inches of rain. Quality going into storage is high with minimal rot. Gravity is high in the processing spuds with a large size profile. Yields have been remarkable, with many processing growers having a surplus over their contracts. Some fields will be disced under, due to lack of storage. Yield records in the province will probably be set this year, despite the drowned out acreage south and east of Winkler. Those growers in the path of that severe weather pattern will have large losses and crop insurance claims this year. Processing of the new crop in the months of September/October is down from 1.7 million hundredweight in 2015 to 1.2 million hundred weight in 2016. Very little open purchasing has been done yet. Fresh pricing continues to be strong with the market driven by the extreme weather and excess moisture in the Red River Valley of North Dakota. Saskatchewan Most of the potato crop had been harvested by Oct. 7. Some areas had seen 10 centimetres of snow in early October, with wind chills of -7 C. Alberta For the most part, harvest conditions were excellent, and a few rain days did not cause any concern. The Central Alberta seed area did have some wet rainy days, which caused harvest to drag on, but it is now complete in that region. Seed quality is excellent – the best in years. Process quality is extremely good. There are some pink rot and soft rot issues that are being dealt with. In terms of yield, seed yield is excellent, early process yields are excellent, storage yields are just average due to a shortage of heat units at critical times in the growing season. British Columbia For the most part, B.C.’s crop was harvested by Oct. 7. There are some growers with full storages who will need to market out of field in order to wrap up. Yields and quality have been excellent. British Columbia was able to begin marketing earlier this year, which should be a big help in moving their crop through distribution channels. Observations on the European crop The North-western European Potato Growers (NEPG) expect production in their five countries (Netherlands, Belgium, France, Great Britain, and Germany) to be down in 2016 by 1.6 per cent compared to 2015, and 2.2 per cent compared to their five-year average. This is due to weather-related issues, even though their planted acreage increased by 4.8 per cent this year. This is a preliminary estimate, as harvest is not yet complete, but this does represent a reduction of 1,000,000 tons. Of particular interest is Belgium, with projected reductions of 12.4 per cent below 2015, and 17.8 per cent below their five-year average. For more information, contact Kevin MacIsaac at This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Oct. 6, 2016, Ontario – A quick survey indicated that about 80 per cent of the provincial potato crop has been harvested by Oct. 5, according to Eugenia Banks, Ontario potato specialist. On the chipping front, Mark Van Oostrum from WD Potato expects that most processing growers will be done by Thanksgiving. Growers in the Simcoe, Ont., area are close to completing the harvest. Joe Lach, who farms near Delhi, Ont., will finish this coming week, and told Banks his remaining potato crop is all sold. About 60 per cent of the acreage near Shelburne, Ont., has been dug. This area plants a bit later than other areas due to cooler spring weather and lower soil temperature. On Oct. 5, Banks harvested a variety trial in Honeywood, Ont. Standard processing varieties such as Lamoka (chipping) and Waneta (chipping and table) did very well. There was no second growth or tuber malformations. By contrast, many of the new varieties under evaluation showed the effects of a hot, dry summer: second growth, bottlenecks, cracks and knobs. 2016 was a great year to see how new varieties perform under heat and water stress.
Wild potatoes acquired from a gene bank in Germany six years ago are producing promising results for Agriculture and Agri-Food Canada researchers trying to develop superior Canadian varieties with resistance to some of the most problematic potato diseases.  Stronger potato varieties will increase yields for Canadian growers, which translates into higher profits.Dr. Benoit Bizimungu, head of potato breeding at the Fredericton Research and Development Centre, said a number of hybrids bred from these wild varieties could be ready for industry trials next year.  Bizimungu selected the German plants because of superior traits such as high yield, as well as strong natural resistance to PVY, late blight, drought, and insects like the Colorado potato beetle.“Although the primary interest was multiple disease resistance and high yield potential, a number of progenies show a nice deep yellow flesh color, which is usually associated with carotenoids,” Bizimungu explains. This is great news for consumers who want more antioxidants in their diet.“What is really exciting is that some of these wild species have never been used in potato breeding before now,” he says. “Using these new parents broadens the genetic base.”“It’s good to have multiple sources for breeding, especially for things like late blight where it keeps changing.”Dr. Bizimungu obtained this unique plant material as a result of his collaboration with potato geneticist Dr. Ramona Thieme of the Julius Kuhn-lnstitut (JKI) at the Federal Research Centre for Cultivated Plants in Braunschweig, Germany.The imported species come from wild potato cultivars that originated in South America, the birthplace of the potato. 
Inside Agriculture and Agri-Food Canada’s (AAFC) high tech Canadian Potato Genetic Resources (CPGR) lab in Fredericton, N.B., hundreds of small glass test tubes contain vital keys to Canada’s potato growing future. The gene bank – a living library of almost 180 potentially high-value potato breeding lines – is an important component of Canada’s ongoing potato research, proof of our commitment to global food security, and our last line of defence against potato disease or natural disaster.
Scientists at Agriculture and Agri-Food Canada's Fredericton Research and Development Centre have developed two potato varieties resistant to the Colorado potato beetle, writes Atlantic Farm Focus. | READ MORE
Those suffering from malnutrition in the global south could soon find help from an unlikely source: a humble potato, genetically tweaked to provide substantial doses of vitamins A and E, both crucial nutrients for health.
Examining the ancestors of the modern, North American cultivated potato has revealed a set of common genes and important genetic pathways that have helped spuds adapt over thousands of years. Cultivated potatoes, domesticated from wild Solanum species, a genetically simpler diploid (containing two complete sets of chromosomes) species, can be traced to the Andes Mountains in Peru, South America.Scientific explorer Michael Hardigan, formerly at MSU and now at the University of California-Davis, led the team of MSU and Virginia Polytechnic Institute and State University scientists. Together, they studied wild, landrace (South American potatoes that are grown by local farmers) and modern cultivars developed by plant breeders. For the full story, click here.
The Environmental Protection Agency and Food and Drug Administration have signed off on three new genetically modified (GMO) potato varieties from J.R. Simplot Company. The three new varieties, Russet Burbank, Ranger Russet, and Atlantic are said to be less prone to bruising and black spot, containing less asparagine, having enhanced cold storage capability, and resistant to late blight pathogens.Simplot believes the resistant varieties will reduce fungicide applications by up to 50 per cent. | READ MORE
One of the more than 70 USDA studies in Maine looking at the effects of crops like mustard, rapeseed and barley in potato rotations. Photo by USDA-ARS If you’re dealing with some tough soil-borne diseases, adding canola, mustard or rapeseed to your potato rotation could help. That important finding emerged from recent potato rotation studies in Maine, led by Dr. Bob Larkin, a research plant pathologist with the United States Department of Agriculture (USDA). Over the last 12 years or so, the USDA researchers have conducted more than 70 trials to investigate the effects of different rotations on soil-borne diseases in potatoes and on potato yields. Although the results varied from year to year and field to field, overall, Larkin and his research team found that crops in the Brassicaceae family, such as canola, rapeseed and mustard, consistently reduced potato diseases like black scurf, common scab and Verticillium wilt, and significantly improved potato yields. Now researchers in Atlantic Canada will be examining the effects of Brassica crops as part of a major potato rotation project. Three-pronged attackLarkin explains there are three general mechanisms by which rotation crops may reduce soil-borne diseases – and Brassica crops likely act in all three ways. “The first mechanism is that the rotation crop serves as a break in the host-pathogen cycle,” he says. “This mechanism is in effect any time you have a rotation crop that does not have the same pathogens as your host crop. This is a general strategy of increasing rotation length by adding other types of crops. The longer the time between your host crop, the more its pathogen population declines.” “The second mechanism is where the rotation crop causes physical, chemical or biological changes in the soil environment,” Larkin says. “It may stimulate microbial activity and diversity, it may increase beneficial organisms, and things like that, which then help compete with pathogens and reduce pathogen populations.” This mechanism varies with different rotation crops. “The third mechanism is where the rotation crop has a direct inhibiting effect on either particular pathogens or general pathogens,” he says. The rotation crop may release suppressive or toxic compounds in its roots or residues, or it may release compounds that stimulate certain beneficial microbes that suppress pathogens. Only some crop species have this mechanism. The first mechanism by itself may not be very effective for controlling some soil-borne pathogens that can survive for many years without a host plant. Brassicas are well-known for the third mechanism. They contain compounds called glucosinolates, and when Brassica plant materials are incorporated into the soil, the glucosinolates break down to produce other compounds, called isothiocyanates. Isothiocyanates are biofumigants that are toxic to many soil fungi, especially fungal pathogens, weeds, nematodes and other pests. Larkin’s research shows Brassica biofumigant activity is greatest when the crop is incorporated into the soil as a green manure. However, even when a Brassica crop is harvested and then the remaining crop residues are incorporated, there is still some biofumigant effect. The amount of the biofumigant effect also depends on the Brassica crop’s glucosinolate levels; canolas have relatively low levels, rapeseeds somewhat higher, and mustards have the highest. “With any of those Brassicas, you will get some benefit from incorporating the crop residues. And it is a measurable and real effect on both potato yield and on reduction of potato diseases,” he notes. As well, Larkin’s studies indicate Brassicas also provide the second mechanism. “Brassicas seem to have an ability to alter soil microbial communities in different ways which is not necessarily related to their amount of glucosinolates or their ability to act as a biofumigant. I think the aspect of how they change the soil microbiology is equally important to their biofumigant effect,” he says. For example, the USDA researchers found that canola and rapeseed sometimes do a better job at reducing black scurf (Rhizoctonia solani) than some of the higher glucosinolate mustards, and the effect on black scurf works even without incorporating the Brassica crop. However, Larkin’s studies also show that managing some other diseases – like powdery scab (Spongospora subterranean) and Verticillium wilt – requires a full green manure. Two-year rotation is too shortIf disease suppression is a major goal of your potato rotation, then Larkin’s research results provide some key factors to consider. First, a Brassica’s disease suppression effect won’t last forever, so the potato crop should immediately follow the Brassica in the rotation to get the greatest benefit. Second, a two-year rotation will not effectively reduce disease in the long run. Larkin found that no matter what crop was in a two-year rotation with potatoes, certain pathogens tended to build up over time. For example, in one 10-year study the researchers compared two-year rotations in fields where common scab and Verticillium wilt were not problems at the beginning of the period. But by the end of the study, both diseases had become substantial problems in all of the two-year rotations. The canola-potato and rapeseed-potato rotations had significantly lower disease levels than the other rotations, but they still had gradually increasing amounts of common scab and Verticillium wilt. “So we recommend a three-year rotation as your first line of defence, and then including a disease-suppressive rotation crop in one of the years of that three-year rotation,” Larkin says. A Brassica green manure could be a good choice for the disease-suppressive crop, or you could grow a Brassica as a full-season crop and follow it with a disease-suppressive cover crop. “The addition of a cover crop like winter rye or ryegrass, in combination with your Brassica, can provide a significant addition to the disease reduction,” he notes. Even though the grower would not be earning any direct income from a green manure or a cover crop, these options can be valuable tools to get serious soil-borne disease problems under control. “That’s really how we first got into this research,” Larkin explains. “Some potato growers [in Maine] had some soils with substantial disease problems, and they wanted to try whatever they could to get those soils back to where their potatoes would be producing better. So they were willing to give up a seasonal crop for a year or two, to try to get the pathogen populations down to controllable levels.” (Two seasons of a green manure might be necessary if the field has very high pathogen populations.) A third factor to consider is whether the rotation crops share any pathogens with potatoes. In Maine, the only shared pathogen that increased in potato-Brassica rotation trials was sclerotinia. In his own studies, Larkin hasn’t had any sclerotinia issues because sclerotinia is not common in Maine potato fields. However, a researcher at the University of Maine found two fields with sclerotinia and did some rotational trials there. Sclerotinia increased in those two fields when canola or rapeseed was in a rotation with potatoes. “So if you have a field with a history of sclerotinia problems, then a Brassica may not be the best rotation crop for you,” says Larkin. Alternatively, adding a cereal crop to a potato-Brassica rotation may help because cereals are not susceptible to sclerotinia. Maritimes rotation projectThe major potato rotation project now underway in Atlantic Canada is examining various crop options including canola and some other Brassicas. Dr. Aaron Mills, a research scientist with Agriculture and Agri-Food Canada (AAFC) in P.E.I., is leading the project. He is conducting trials at AAFC’s Harrington Research Farm in the province, involving nine different three-year rotations. The project is funded under Growing Forward 2, with support from AAFC and the Eastern Canada Oilseeds Development Alliance Inc. McCain Fertilizer division is collaborating by conducting a similar study in New Brunswick. Generally, the project’s three-year rotations involve a year of potatoes, a year of another high-value crop, and a year of a more diverse crop mix or a biofumigant crop. “We’re looking at canola, soybean and corn [as the high-value crops], and at other, more diversified phases in the rotation, including blends of a Brassica, a grass and a legume all planted at the same time,” Mills explains. He notes, “The canola acreage is increasing slightly in Prince Edward Island, it is one of the higher-value oilseed crops, and it does very well under our climate. And it’s important to diversify the cropping system, so if you can add in a different crop and it’s a higher value crop, then that’s a win-win situation. “Canola has also been touted to have some biofumigatory effects, and the Brassicas in general produce certain compounds shown to have effects on diseases and insect pests,” Mills says. “Buckwheat is another [crop that supresses pests], based on research by my colleague Dr. Christine Noronha, so we’re also including buckwheat in the trials.” Mills and his research team will be scouting all the crops in the different rotations for disease and insect pests. Sclerotinia is one of the issues they’ll particularly watch for. Mills notes, “We are starting to see an increase in sclerotinia [in P.E.I.], and a lot of the higher value crops in these rotations are hosts for sclerotinia.” Along with collecting data on crop yields, diseases and insect pest issues, the researchers will also be monitoring such factors as crop biomass and soil organisms including nematodes. And Dr. Judith Nyiraneza, an AAFC nutrient management specialist, will be tracking nutrient dynamics in the soil. The researchers conducted preliminary work in 2013, and 2014 was the project’s first full year. The current funding will take the project to 2017-18, but Mills hopes to run it for nine to 12 years. “You can’t really look at the trends until you get at least a couple of phases of each rotation. So one of the big determinants for the project’s success is how long we can run the rotations,” he says.   Putting it all togetherThe effects of different rotation crops on potato diseases and yields may differ somewhat from region to region. Mills emphasizes the importance of evaluating rotations in different regions: “P.E.I. soils are different than those in Ontario or out west, and how the crops respond is not exactly the same.” Mills’ overall advice for effective potato rotations is that more diversity is better. “From what we’ve seen so far with some of our other studies, it’s all about increasing the crop diversity. You can increase the length of the rotation by adding different crops. Or, if you have a shorter rotation, you can increase [the in-year diversity]. That seems to show some benefits to the soil and to the organic matter especially,” he says.    Similarly, Larkin advises using multiple rotation-related practices for enhanced disease suppression. Examples include: increasing the rotation’s length, adding crops that also have the second and third mechanisms of disease suppression, and including cover crops and green manures. His research shows that, although these practices will not completely eliminate potato diseases, they will reduce soil-borne potato diseases and improve potato yields. As well, these kinds of sustainable practices provide other long-term benefits for a farm’s production capacity and potential longevity. These benefits include improving overall soil health, enhancing soil microbial diversity and activity, increasing soil organic matter and building a healthier agro-ecosystem. “All these practices are components of making a better, more sustainable system,” Larkin says. For potato growers in Maine, Larkin’s general rotation recommendation is “a three-year rotation, with one year of a grain such as barley, then a cover crop like ryegrass or winter rye, then a Brassica, which could be a mustard green manure or a harvestable oilseed Brassica crop, and then potato in the third year of the rotation.” He notes, “That recommendation is based on a lot of different studies looking at what is the best system for reducing disease, what is the best system for improving soil quality. Now [in our current studies] we are trying to combine those into a rotation that incorporates aspects of all of those things and seeing if it really does everything we hoped it would.”  
Sept. 25, 2014, Prince Edward Island – A new method of applying fertilizer to potato crops, with the intent to grow a more desirable potato while cutting down on costly fertilizer waste, is showing promise in Prince Edward Island, reports The Guardian. | READ MORE
Southern Alberta is well known as cattle country, but the region also is home to significant commercial potato production. Now, a partnership between a potato grower and cattle producer has proven to be a fortuitous – albeit rather unorthodox – opportunity to unite the two industries for mutual benefit. Harold and Chris Perry are co-owners of the Kasko Cattle Company, with feedlot owner Ryan Kasko, on 10 quarter-sections of land surrounding the Kasko Cattle Company feedlot east of Taber, Alta. Kasko owns and operates the feedlot itself, which raises about 14,000 head of cattle annually. Harold Perry says they partnered with Kasko in the recent purchase of the land surrounding the feedlot partially because it provided them with a ready supply of manure that they could convert to compost for use in their potato production. The potato producer benefits primarily from the nutrient and micronutrient value delivered by the feedlot’s manure when it is applied on potato cropland in the form of compost, while the feedlot has a handy place to dispose of its significant accumulation of manure right nearby. The feedlot owner delivers the raw manure to a dedicated composting site with good drainage control where the potato producer converts it to compost. It is land applied in October and worked in before the potato hills are created for next year’s planting. The Perry family’s expertise, which includes Harold and Chris’ father, Gerald, is in producing crops such as potatoes, sunflowers and peas on a total of 4,600 owned and rented acres. Their business is headquartered close to the town of Chin, about 40 kilometres from the feedlot – a typically hot, dry climate requiring irrigation, with plenty of frost-free days. The Perrys have a contract to produce 13,500 tonnes of potatoes for Frito Lay and 8,500 tonnes of potatoes for McCain Foods on about 1,300 acres that are under irrigation for that purpose. For the past decade, the Perrys have used cattle manure compost as fertilizer in their potato-growing operation because of the nutrient and microbial benefits they’ve realized from using it. Harold Perry says they observed with growing potatoes on virgin potato growing soil versus soil that had been under cultivation previously in a four-year potato crop rotation that there was a dropoff in potato production on soil where potatoes had been grown in the past. They discovered that using compost on the potato rotation land not only provided organic fertilizer to the crop but also worked as an excellent soil amendment, adding many micronutrient and biological unknowns to the overall quality of potato-growing land that really made a difference in commercial potato production. “We wanted to try compost because that is the natural way that things work,” says Perry. “When the buffalo were here, they ate and manured the grass at the same time, and that’s how the natural cycle worked. Fertilizer prices have also helped because compost makes sense if you go strictly by dollars. The cost of putting the amount of nutrients you put on your soil using compost is less than if you were to purchase that at a fertilizer dealership.” Composting the manure deals with that issue, and it is also more economical to transport nutrients in this form than as raw manure. The Perrys can attest to that fact. “Good compost has about 60 per cent of the weight of raw manure,” says Perry. “So if you get too far away from the feedlot, then the trucking just kills you.” Research being conducted by Agriculture and Agri-Food Canada, specifically in Summerland, B.C., also is showing that the addition of compost could help in the prevention of verticillium wilt, also known as early dying syndrome. Potato crops infected with this pathogen will typically see the tops of potato plants die off between early August and September, which can have a devastating impact on potato production in the case of a bad outbreak. The pathogen enters the plant through root lesions. The root lesions are caused by nematodes that live in the soil and feed on the roots. So far, what the B.C. research has shown is that the addition of compost enhances the presence of a fungus that feeds on the nematodes, thus reducing the amount of root lesions and closing the pathway for the verticillium wilt pathogen to enter the plant. Results so far have been promising, although the theory hasn’t quite been proven yet, according to Dr. Frank Larney, research scientist in the area of soil conservation with Agriculture and Agri-Food Canada (AAFC) at the Lethbridge Research Centre in Alberta. Before the Perrys became partners in the feedlot, they were purchasing their compost from a commercial supplier. It was partially because of compost quality issues that they agreed to invest in land surrounding the Taber area feedlot with Ryan Kasko so they could acquire their own supply of raw cattle manure to manufacture compost. The Taber feedlot and surrounding land were also near their potato growing operations, so all the pieces conveniently fell into place. Harold Perry is in charge of compost production. “If I have a goal, it’s to have healthier soils, for healthier crops, for a healthier population,” he says. The Perrys pay Kasko for the cattle manure, and he in turn hires a custom contractor to deliver the raw manure to the compost production site. The custom manure hauler creates the windrows needed to produce compost. During the first year of compost production, the feedlot delivered about 9,000 tonnes of manure to the site. Delivery of the manure resulted in four windrows measuring a distance of about half a kilometre each. Once the windrows were created, Perry began monitoring the conversion process and used his compost-turning equipment as needed. He acknowledges feeling a bit anxious about delving into compost production because of the science required to ensure that the biological organisms have a healthy environment to carry out the conversion process but adds that learning to compost has been an enjoyable experience. To prepare himself, he took a composting course offered by Midwest BioSystems. The conversion process takes from July to mid-October. To turn the compost, Perry purchased a 14-foot wide, pull-type, Sittler compost turner, which retails for about $45,000. He was able to recoup about half the cost by applying to a government program called the Growing Forward Manure Management Program. He checked the heat and moisture content in the composting windrows regularly to ensure that the organisms were working in an optimum environment. He also purchased a Sittler water wagon that can be towed along with the compost turner so that moisture can be applied to the windrows as needed. Perry says he turned the compost six or seven times with the main determining factor being when the temperature in the compost heap reached 160 F. At the beginning, the turning was done every four or five days because of the strong biological activity underway. Ideally, the conversion process should take 10 weeks, but Perry says he prefers to wait 16 to 20 weeks. As part of the Perrys’ adventure into composting, they hired an agriculture consultant from Sunrise Ag in Taber to soil sample and develop topography maps to help determine how much compost should be applied at various points on their cropland. The consultant developed maps showing six zones where the compost should be applied to a lesser or greater extent to achieve ideal growing potential. To spread the compost, Perry purchased a Bunning compost spreader with vertical beaters, which he pulls using a John Deere 8430 tractor equipped with hydrostatic drive. Perry recommends a tractor in the 180- to 200-horsepower range. The tractor moves at about 16 kilometres per hour, and the spreader broadcasts the compost over a width of about 40 feet. This results in an application rate of about four tonnes per acre. Increasing or decreasing tractor speed based upon the zone mapping displayed in the cab will increase or decrease the application rate. Larney says he is not surprised by the results witnessed by the Perrys. He says using compost in the lighter, sandier soils under irrigation in southern Alberta delivers “a better bang for your buck” than perhaps it would in the soils where seed potatoes are grown in central Alberta. These soils typically contain more organic material. Given the amount of row crop type production in southern Alberta and because these crops do not return organic matter to the soil, Larney says, “the addition of compost is a very good way of replenishing soil organic matter . . . it’s the quickest way.” He adds that compost also delivers other benefits, such as the addition of micronutrients not present in commercial fertilizer, and also improves the soil’s water holding capacity, making it more resilient to both wind and water erosion. Given how close together both cattle and potato production are in southern Alberta, he says their co-operation is a natural fit. “It kind of makes sense that it (manure) should end up on potato land,” says Larney. He is noticing more feedlot operators moving in the direction of composting the manure in advance versus simply land applying raw manure. “I think a lot of feedlots are now realizing that they should look at composting because you can only rely on your neighbours for so long to take raw manure,” he says. “With the buildup of phosphorus levels in particular close to feedlots, I think the onus is on the feedlot owners to hopefully ensure that these nutrients are spread out over a wider area so that we are not getting high nutrient loading on land close to the feedlot.”
Potato crops require large amounts of most inputs and potato growers seek economical alternatives for what this high-value crop requires.
One day soon, you might be able to give your potato crop an extra boost from beneficial bacteria, thanks to some innovative studies by Ontario researchers.
Adjusting fertility programs by the tiniest increment could net a yield increase. All that might be required is better understanding the soil’s needs or choosing nutrient materials that will work more effectively in particular soil profiles. Three top potato experts share their tips for tweaking fertility that are valid for any potato operation. While most of the recommendations are not new, they may be getting overlooked or they may need to be combined with others in order to get better results.
The practices used in selecting and preparing seed potatoes for planting play a big role in getting your crop off to a great beginning.
Ever since becoming widely used in Canada in the late 1990s, neonicotinoid pesticides have helped keep Colorado potato beetle (CPB) populations in check. But the pest could be poised for a comeback, due to growing CPB resistance to neonics and the prospect of the Group 4 insecticides being banned from Canadian potato farms.
Lso (zebra chip pathogen) has been detected in small numbers of potato psyllids in two sites in Alberta, but no zebra chip symptoms or pathogen has been found in any potato plant tissue yet.During three years of sampling for potato psyllids (Bactericera cockerelli) across Canada, we foundsmall numbers in Alberta (2015-2017, increasing annually), Saskatchewan (first time in 2016), andManitoba (first adults, 2016). No potato psyllids have been found on sample cards from any siteseast of Manitoba.In southern Alberta, the range of potato psyllids has expanded to sites throughout the potatogrowing area, where in 2017 they appeared on sampling cards of over 70 per cent of 45 sites regularly sampled (we thank the growers for co-operation and access to University of Lethbridge samplers at 45 sites, with a minimum of 4 sampling cards per field, and Crop Diversification Centre South for managing two additional sites and sending sample cards). For the full story, click here. 
While there are no "silver bullets" for combating wireworm, with ongoing research, Island farmers do have more options.Christine Noronha, of Agriculture and Agri-Food Canada, has unveiled an effective wireworm trap. "The trap is a very simple light trap, called the NELT. It uses a solar powered light source to attract the adults of wireworms, click beetles. The beetles walk to the light and fall into a cup buried in the ground under the light,"  Noronha explained.This is the first trap that catches female click beetles. Trapping the egg-laying females will gradually help reduce the wireworm population in the field. For the full story, click here.
Researchers are hoping Canadian potato growers will soon be able to use an innovative approach to control wireworms. This method uses just a few grams of insecticide per hectare applied to cereal seeds that are planted along with untreated seed potatoes. It provides very good wireworm control for the whole growing season, with a lower environmental risk than currently available insecticide options.
Just because black cutworms don’t overwinter in Canada doesn’t mean they aren’t a threat to potato crops. The insects spend their winters in the southern United States but travel north on low-level jet streams and, once they cross the border into Canada, they look for a tasty food source. Black cutworm moths prefer some of the weeds that grow in and around fields and, while potatoes are not their favourite food, they will adapt and can wreak havoc on an unmonitored field. A researcher at the University of Minnesota says the cutworms’ new interest in potatoes could be the result of a change in potential host plants. If the moth’s desired weed is being well controlled in a field, it will eat what is available where the wind sets it down. “Black cutworm moths are active flyers,” explains Ian MacRae, the extension entomologist at the university’s Crookston research station. “These insects can travel hundreds of miles in a short period of time aided by an extremely efficient bug highway [a jet stream].” MacRae says if the wind and temperature are conducive and Canadian potato producers are able to get their crop planted in good conditions, there is a chance the moths will arrive about the same time as the plants are emerging. The possibility exists that early arrival could spawn a second generation of the insects later in the season. He says, once landed, reproduction occurs when the moths lay eggs. The emerging larvae will feed on the foliage, but once at the fourth or fifth larval stage they will begin actively eating near the base of the host plant, cutting it off. “The first you might notice a cutworm problem will be plants that are cut at the base or wilting,” MacRae explains. “At night, the worms burrow into the soil and if the tubers are close to the surface, they will burrow into the tuber. They can do more damage to tubers in dry conditions because cracks in the soil will give the cutworms access to what is underneath.” Damage to potato crops early in the season can be a greater problem because the young plants will not recover from being chewed off. There is a possibility that the seed piece might send up another shoot, but the crop will be set back. MacRae suggests early scouting will help identify the problem and allow time for control. There are effective insecticides for control of black cutworm and there are sources of natural mortality, such as predators or parasitic wasps. Birds may be less effective because of the location of the worms and their habit of eating at night. “If you find yourself at a threshold of about 30 per cent of your plants cut, you may want to apply an insecticide,” MacRae says. “If defoliation is this high, it may be that natural mortality sources are not functioning well.” Ensure proper identification of the larvae as black cutworms so the correct product can be chosen for control. Combining regular field scouting with pheromone or light traps to catch the male moths is an effective way to identify the insects. “When scouting, look for stalks at an odd angle or wilting,” MacRae suggests. “Look in the evening when the cutworms come out to feed, and look as much as a half metre away from the plant because they are good walkers. Black cutworms are aptly named because they are a dark caterpillar with a waxy appearance. They will often curl into a C if disturbed. They hang out during the day under clods of soil or in cracks.” MacRae says climate change may be the reason black cutworms are being seen farther north. He doesn’t believe they will begin to overwinter in Ontario or the Prairies, but a warmer climate means they develop faster and may overwinter in more northern states, making the migration north earlier and causing greater problems. “Black cutworms have certainly become a problem in Ontario in the last few years,” MacRae says. “They can be a significant pest issue.” MacRae adds there are some cultural practices that may minimize the impact of black cutworms when they arrive. Planting late can put new, young plants directly on a collision course with the moths and their offspring, so plant early, if possible. He says controlling weeds will reduce the areas where the moths might lay eggs. Growers in the United States use pre-plant tillage to turn over the soil to destroy potential habitat. To date, there is no accurate monitoring system in place for potato crops, according to MacRae, but the cutworms also like corn and the corn growers in some states, such as Iowa, have a black cutworm monitoring network. “The moths seem to appear in Ontario about three weeks after they are seen in the United States,” he says. Ontario growers could tap into the monitoring networks south of the border and use that information as an early warning system, he suggests. Black cutworms could be considered a stealthy yield robber because by the time you begin to notice a problem, it could be a challenge to execute effective control. The best defence is early and frequent field scouting and adopting cultural practices that could minimize the attractiveness of the crop. MacRae believes Canadian potato growers will see black cutworm more often in the coming years, so preparation for and understanding of the pest is a wise approach.   
Agriculture and Agri-Food Canada scientist Louis-Pierre Comeau is sifting his way through New Brunswick soil in search of answers to one of the biggest issues facing local farmers: the loss of soil organic matter and the decrease of soil health in farm fields.
Rob Green, a potato farmer in Bedeque, is taking cover crop rotations to a new level. In the past, he grew barley, canola and hay as his rotational crops.
With the help of DNA sequencing, Canadian researchers are linking soil microbial communities to soil health and potato yields. This research is the first stage in eventually developing a tool to diagnose the health of potato fields and to help identify management practices to improve tuber yields and quality.
Brenda Shanahan, Member of Parliament for Châteauguay—Lacolle, on behalf of Minister of Agriculture and Agri Food Lawrence MacAulay, has announced a repayable contribution of $470,000 to help a Quebec company, Logiag Inc., commercialize a laser-based soil analysis system that replaces the more traditional chemical analyses.
Studies have shown adding biochar to soil can improve soil fertility, increase nutrient utilization in plants, improve soil water-holding capacity, increase crop yield and reduce emission of greenhouse gases. However, if you are a potato farmer, your joy may be short-lived. According to research from Aarhus University in Denmark, biochar and potatoes do not go together very well, especially if you’re aiming to save water. Caixia Liu, a PhD student in the university’s department of agroecology, investigated the effects of adding biochar produced from wood on potato growth, yield, nutrient uptake and water utilization when three other factors were also taken into consideration: irrigation methods; phosphorous fertilization; and inoculation with a certain class of beneficial fungi. Liu’s aim was to investigate the interactions between biochar and the fungi on the growth of potatoes. Biochar and AM-fungi do not go well togetherPotatoes are rather sensitive to drought and phosphorous deficiency because of their relatively small root system. It would be easy to merely irrigate and fertilize in plentiful amounts, but since both phosphorous and water are limited resources, it is important to use them optimally. Earlier studies at Aarhus University have shown water can be saved by irrigating alternately on each side of the potato ridge and letting the other side remain dry – the so-called alternating partial root zone drying irrigation method. It is also possible to save phosphorous. In the course of her PhD studies, Liu found inoculation of potatoes with the beneficial arbuscular mycorrhizal fungi (AM fungi) can improve potatoes' utilization of phosphorous, make utilization of water more efficient, and increase potato yield in crops that are stressed due to drought or phosphorous deficiency. The question was what would happen when biochar and inoculation with AM fungi are combined. Would there be a double win? The answer was no. Liu conducted a series of studies with various combinations of irrigation (either full irrigation or alternating partial root zone dehydration), phosphorous fertilization (none or 0.11 milligrams of phosphorus per gram of soil, or mg P/g soil), inoculation with AM fungi (inoculation or no inoculation) and addition of biochar (addition or no addition). Biochar inhibited the growth of potatoesIf the crop is irrigated fully, the soil is given no phosphorous at all, and the potatoes are not inoculated with AM fungi, then addition of biochar can increase potato yield. This was the only case in which this was true; in all other instances, addition of biochar to the soil had the opposite effect. The negative effect on potato growth was especially pronounced when phosphorous was added, alternating partial root zone drying irrigation was used, and the potatoes were inoculated with AM fungi. Addition of biochar inhibited the growth and vigour of young potato plants. Some of the young potato plants even died. “I would recommend that the farmer refrains from adding biochar produced on the basis of wood to an AM system, where the soil has been fertilized with phosphorous or if the soil is prone to drought. Biochar remains in the soil for a long time so there is no going back,” Liu said, in a press release.
Due to hot, dry conditions, farmers in Norfolk County, Ont., have used irrigation in an effort to save the crop. But with less than half an inch of rain in eight weeks, irrigation has been no use, and the local yield could be down by 50 per cent. | READ MORE
A detailed understanding of the psychrometric chart can be an excellent tool in understanding water, air and vapour relationships.
After a final holding temperature is achieved in storage, it is important to ventilate properly in order to manage the byproducts of respiration, ensure a uniform temperature and an ideal environment for the duration of the storage period, which will maximize the value of the crop.
What potato grower wouldn’t want to add dollars to their bottom line? By reducing the bruising that occurs during harvest by one percent, thousands of dollars could be added to the bank, according to research completed at the University of Maine. The solution is to minimize the potential for bruising before the harvester enters the field, but growers in a hurry often overlook this most basic crop management rule.
Just because a disease cannot be seen on a potato does not mean it is not there. It is the unseen spores that can cause havoc in long-term storage and require early shipping or the worst-case scenario: the loss of the entire bin. What if a test could be done that would predict the potential for disease in a crop?
Usually wet seasons favour crop development, but incidence of storage rots is a concern, especially if rainfall occurs late in the growing season, advises Eugenia Banks, Ontario potato specialist.

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