Late blight disease, caused by the pathogen Phytophthora infestans, continues to be one of the most serious disease concerns for potato growers. Over the past few years, new genotypes of P. infestans have emerged creating new management challenges for commercial potato growers.
Creative solutions are needed in the battle against bacterial diseases in potato. In people, most bacterial diseases are treated with antibiotics, but due to the rise in resistant bacterial strains, that option, apart from a few exceptions, is off the table for field-scale agriculture.
Zebra chip is a serious disease that can kill potato plants, significantly reduce yields, and make infected tubers unmarketable. It was first documented in Mexico in 1994 and in Texas in 2000. Since then, it has spread northward through much of the Western United States, as well as to Central America and New Zealand.
A biopesticide for managing common scab would be an exciting advance for two key reasons, explains Dr. Martin Filion with the Université de Moncton.
2018 saw fewer problems with wireworm in Atlantic Canadian potato fields than past years, according to Christine Noronha, a research scientist for Agriculture and Agri-Food Canada based in Prince Edward Island. But this doesn’t mean the problem has gone away.
For potato growers, one of the most concerning and costly diseases is late blight, caused by the pathogen Phytophthora infestans. Estimated to cost almost $10 billion per year worldwide, late blight spreads by spores and can spread quickly in a field. Post-harvest losses can be substantial if infected tubers are harvested and stockpiled. Like other disease pathogens, new strains and novel genotypes of P. infestans have emerged over the past few years, creating new challenges for commercial potato growers.
Overall potato production in Canada dropped by 2.6 per cent, according to the latest estimate from the United Potato Growers of Canada (UPG).
Some areas of Canada did have a tough harvest due to cold, wet conditions resulting in these areas having lower than normal production, but there's no spud shortage yet, says Terence Hochstein, executive director of the Potato Growers of Alberta (PGA).
From stalled harvests to abandoned acres, to potential storage problems, Canadian potato growers have not had an easy harvest.
P.E.I Potato Agronomy shares harvest considerations for Island producers battling tough harvest conditions, including disposing of tare soil properly at storages, thoroughly cleaning shared equipment to reduce biosecurity concerns, and taking care of producer wellness through available support programs. | READ MORE
There is a good chance Manitoba will fall short of its contract amounts after damaging frosts froze some fields before salvaging, said Dan Sawatzky, manager of the Keystone Potato Producers Association, to the Manitoba Co-operator. An estimated 30 per cent of potatoes were still in the fields when temperatures dipped to below 10 degrees Celsius in mid-October, topping off two weeks of unseasonably cold weather. Some producers are attempting to manage frozen potatoes in storage, while others have decided to opt out of any further harvest attempts.Even for farmers with insurance, the abandoned acres still have a huge financial impact on farmers. Despite frost and rain disturbing harvest progress, Manitoba potato crop has had a relatively good disease year. There was no late blight found in Manitoba and the season was remarkable for very low aphid numbers and low levels of early blight, according to Dr. Vikram Bisht's Potato Disease report for Manitoba Agriculture. However, black dot incidence was extensive and there was widespread Verticillium wilt earlier than normal in many fields.
Cold and wet conditions in September and October has some Saskatchewan producers opting to leave potatoes out in the field instead of incur the cost of digging the crop out. Multiple nights of hard frosts have damaged potatoes near the surface and the damaged potatoes can cause healthy potatoes to rot in storage.
The P.E.I. Potato Board is using its seed farm in Fox Island, P.E.I., to get new varieties into Island fields quickly and safely.
Barcelona, a yellow-fleshed variety with smooth skin, was the highest yielding variety in a non-irrigated trial just northwest of Hamilton, Ont., according to Eugenia Banks' latest potato update.
Yellow Sun, Red Smile, Kiss-me-a-lot and Lobster Red are four unique varieties of potato to be grown in Newfoundland and Labrador for the first time.
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
In Ontario, the hot summer temperatures in 2018 reduced potato yields even under irrigation. A few cases of heat necrosis and/or calcium deficiency due to drought and heat stress were also reported. The hot, dry start for potatoes in many parts of Canada, combined with challenging harvest conditions that left many unharvested acres, resulted in lower overall production.
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.
With renewed funding, the Potato Growers of Alberta (PGA) will continue to run pest and disease programs to help the Alberta potato industry during the 2019 growing season, according to an update by agricultural director Thomas McDade.
Ontario corn producers are dealing with high-DON (deoxynivalenol) in grain corn this year. High amounts of the mycotoxin are harmful to animals, so high-DON corn is unsuitable for feed and producers have limited end use options.
Potato farmers in P.E.I. are planting more mustard to ward off wireworm and boost crop yield.
A research scientist at Agriculture and Agri-Food Canada in P.E.I. is looking for natural ways to deal with click beetles and wireworms that cause damage to potatoes.
Eight spore traps have been set up in potato fields across Ontario to help detect spores of late blight, according to Eugenia Banks' latest potato update.Two spore traps are located in the Shelburne-Melancthon areas at D & C Vander Zaag Farms Ltd. and two others in the Alliston area at Mark and Shawn Murphy Farms. In the Delhi area, two spore traps are set up at Joe Lach's Farm and Fancy Pak Brand Inc. The final two spore traps are located in the Leamington area at Harry Bradley and Sons Farm. Alliance Agri-Turf, Bayer CropScience, FS Partners, Holmes Agro and Syngenta provided funding for the 2018 late blight spore trap project. A&L Laboratories in London, Ont. will conduct the polymerase chain reaction (PCR) tests to identify the presence of late blight spores. The results will be shared with growers and positive PCR tests indicate the presence of spores. Early detection helps alert growers to add late blight-specific fungicides into their mix.In the past two years, Eugenia Banks, a former potato specialist for the Ontario Ministry of Agriculture, Food and Rural Affaris (OMAFRA), led a project evaluating passive spore trapping technology to help growers improve late blight management. The project recorded positive results. Spores were detected 15 days on average before late blight lesions were seen in a few fields. A previous Potatoes in Canada article goes indepth into the project and how effective spore traps are for preventing late blight. “Spore traps represent another tool to be added to the potato growers’ arsenal to combat late blight,” Banks says. “If late blight spores are not detected by the traps, growers should still follow a preventative fungicide program and apply a fungicide spray before rows close. Also, fields should be scouted regularly.”
The practices used in selecting and preparing seed potatoes for planting play a big role in getting your crop off to a great beginning.
When you think of China, do you think of potatoes? Maybe not, but in the Loess Plateau region of northwestern China, potato is the main food crop.
Manitoba, in general, had a slightly delayed start of planting in 2018; about a week later thanin 2017, reports Vikram Bisht in the first Manitoba Potato Disease Report of the season. The majority of planting started in first week of May, and mostly finished by the end of May. Early planted fields have good emergence. June 1 has been set for initiation/accumulation of P-Days and late blight Disease Severity Values. P-day is a measure of heat available for crop growth and development, and values accumulate when temperatures range between 7 C and 30 C.Weather conditions since planting have been very warm, with a few days over 30 C. Precipitation has been below normal for May, except for a few scattered heavy rain events towards end of May. This week’s rain should help ingood emergence and stand. The current soil temperatures are 2 C to 5 C warmer than end of May last year. These warm soil temperatures and may speed up emergence.Cull piles are an important source of inoculum for many diseases including late blight. It is important to dispose of properly the cull piles before thunderstorms arrive.
The most recent reports coming out of a 20-year study on P.E.I. soil health are showing a general decline in soil organic matter (SOM). The news is causing alarm, but for Vernon Campbell, a potato farmer, the headlines aren’t all that shocking. In fact, he said it’s a situation Island producers are already actively working to fix. | READ MORE
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.
This article was republished from a 1999 article in Top Crop Manager.The basic principles of potato storage have not changed much over the years. The computer age has allowed growers to more precisely control their humidity and ventilation operations, but the need to minimize disease, cool the pile, reduce shrinkage and preserve the crop until shipment remains essentially the same.Every storage situation is different, according to John Walsh a former potato storage management specialist for the New Brunswick Department of Agriculture and now an agronomist with McCain Foods in Florenceville. However, he has a basic strategy that he shares with growers, which holds true for most situations: growers can adjust to suit their operation.“There could be 1000 management situations,” Walsh explains. “But we've developed a strategy for storage management that begins with evaluating the crop for rot potential. For example, if a grower sees late blight late in the growing season, a flag should go up. If soil is saturated for more than 24 hours, another flag goes up. If there is rain during harvest — another flag. If rot is seen during harvest, that's another flag. If there are no flags, the grower can go ahead and start curing the crop. If a grower only has one flag, only a couple days of drying will be needed. If there are two flags, a couple weeks of drying may be necessary. If there are three flags, it would be best to turn the humidifier off, turn the fans on, and leave them that way because it could take more than two months to dry the crop. In the end, a little extra shrink is better than potatoes flowing out the door!”The goal of all growers is to prevent rot from infecting the entire warehouse. Once taken care of, there are four steps to follow: curing, cooling, holding and removal of the crop from storage. If all are accomplished with no problems, a grower has completed the second stage of crop production, the first being the actual growing of the crop.The curing process helps heal wounds and set the skin on the tubers, reducing any opportunity for disease to infect them. Walsh says the curing process is slightly different depending on how the potato is to be used. In the case of processing potatoes, he says, a colour evaluation must be made first and then the curing process can begin. “Tablestock and seed can cure for two to three weeks at 50 degrees F, while chip and French fry potatoes should cure for three to six weeks at 55 degrees F,” he reminds growers. “Once curing is over, growers begin the cooling process by dropping the temperature two to three degrees a week for tablestock and seed, and one to two degrees a week for processing potatoes.”When cooling is complete, the potatoes are held at the recommended temperature for each type until delivery to processors or consumers. Processing potatoes may require warming to 55 degrees F for a few weeks before delivery to improve colour, otherwise the important thing is to maintain uniform conditions. Walsh says as long as rot is controlled, many problems facing growers will be manageable. However, he admits there is little growers can do to minimize the effects of rhizoctonia or silver scurf once they have infected the storage. He maintains growers need to concern themselves more with wet rots and dry rots because, with effective cooling, curing and holding, they can be minimized.Some products will help control dry rot, but they have limited use due to resistance to the control product. Ross McQueen, a potato pathologist in the Faculty of Agricultural and Food Sciences at the University of Manitoba in Winnipeg, says thiabendazole has been effective on dry rot, but resistance is beginning to appear in Western Canada. “We're currently working with chlorine dioxide to control secondary infections that come from late blight,” he says. In this trial method, “The chlorine dioxide is delivered through the humidity system.” He says the method shows promise because it reduces the populations of the bacteria that cause rots that result from late blight.Walsh recommends growers minimize dirt and mud going into storage as well as avoiding over-filling warehouses.Occasionally, growers try to fine-tune their storage operations to reduce disease by using multiple ventilation systems or opting for newer insulating materials, but the basic principle of good storage remains the same, says Walsh. “Work continues to develop expert systems to run the computers that manage the storage,” he says, “but the basics remain the best management system.”A grower who has developed his own expert system is Keith Kuhl of Southern Manitoba Potato Company of Winkler, Man. He says after trying a number of computer environmental control systems, including “a cumbersome program” from a technology company in the U.S., he met with a local electrical company and developed his own system. “Ours is a much simpler system than any others that are on the market,” he says. “We determine a long-term goal for each warehouse and the computer is adjusted to maintain temperature and humidity until the planned shipping date.”Kuhl says his company ships 12 months of the year and, as a result, his crop is managed with that in mind from the time it is planted. “In the cooling process, we know what our long-term plan is for that crop, so each bin may be treated differently depending on the market or delivery date.”However, despite an efficient, easy-to-use computer program, Kuhl relies on regular visual inspections using temperature probes and his nose to sniff out any problems. “A good manager should rely on his sensory perception,” he says. “If you detect sour smells, you know you might have some problems in that bin.” For damage control, he may use the chlorine dioxide product, Purogene, in his ventilation system, but he would prefer to eliminate potential problems before this step is needed. This product recently received an extension of its 'emergency use' registration until June 2000.Finally, the trick for successful storage is to never quit monitoring the warehouse. Take note of any 'flags' as the crop is being put into storage and adjust humidity and ventilation to minimize problems. Then, throughout the winter, maintain systems and monitor the crop to eliminate any surprises when the trucks start loading to take the crop to its final destination.Kuhl says he is always ready to adjust his plans. For example, if a problem is found in a field slated for 10 months of storage, he may decide to move those tubers out of storage earlier than he had planned. He also says he selectively harvests to reduce problems. If the season has been wet and low areas are still wet, he may choose not to harvest those areas. He might also harvest them separately and store them in a different bin where the curing/cooling process can be adjusted to meet the needs of those tubers. If he sees a higher percentage of culls in a field, he may monitor that crop more diligently when it is in storage. He suggests keeping good records at harvest, noting the conditions of harvest and the pulp temperature of the potatoes going into storage and recording any disease potential.“Storage management is like managing a completely separate crop,” says McQueen. “There are multiple factors growers need to take into account and manage the storage accordingly.” Savvy growers, like Kuhl, understand this concept and try to remain on their toes when their potatoes are in the bin although the basic storage principles remain the same.
It’s not about how you start, it’s how you finish – and this potato season is not over yet. Canadian potato producers endured a tough harvest season, especially Prairie and east coast producers who were faced with abnormally cold wet weather that delayed harvest until early November.
Lorraine MacKinnon, PEI potato industry coordinator with the Department of Agriculture and Fisheries, says it’s not a nice position to be in now to start contemplating potential issues going forward with storage after a difficult harvest. MacKinnon created a checklist for producers to use during their daily warehouse visits that help identify symptoms of larger problems. Storage problems are better tackled sooner rather than later.
Prairie and east coast potato producers endured a prolonged harvest of excessive rain and cold temperatures. After a difficult harvest, it’s time to look ahead to the storage season.
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.
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2019 Training Session for Potato ScoutsMon Jun 03, 2019 @10:00AM - 03:30PM
Potato Association of America Annual Meeting Sun Jul 28, 2019
Process Expo 2019 Tue Oct 08, 2019
Alberta Potato Conference and TradeshowTue Nov 19, 2019