Are two cultivars better than one? Performance of leafed and semi-leafless pea mixtures under weedy conditions

Non-Peer ReviewedThere is a need for improved tools to minimize yield losses due to weeds for organic field pea production. Cultivar mixtures may improve the ability of organic pulse crops to suppress weeds and maintain yields in the presence of weeds. While semi-leafless peas are known for their lodging resistance and high yield potential in the absence of weeds, leafed (wild-type) peas may provide better weed suppression and yield stability in the presence of weeds. A replicated field experiment was conducted on organic land over five site-years to test the hypothesis that mixtures of leafed and semi-leafless field pea cultivars would improve weed suppression and yields relative to monocultures of the same cultivars. The experiment tested factorial combinations of five ratios of semi-leafless (cv. CDC Patrick or CDC Dakota), and leafed pea (cv. CDC Sonata) (0:100, 25:75, 50:50, 75:25, and 100:0, respectively), and two target seeding rates (88 and 132 plants m-2). Plots were monitored for crop and weed emergence, biomass, and yields. Mixtures differed from their component monocultures in both weed control and yields. Levels of weed control in mixtures were intermediate to the component cultivars, and no weed control benefits were seen. While CDC Patrick mixtures did not out-yield CDC Patrick monocultures, mixtures of 75% CDC Dakota and 25% CDC Sonata out-yielded both respective monocultures by 12-196%. Results indicate that mixtures of leafed and semi-leafless cultivars may be used to improve organic pea yields in the presence of weeds. However, specific combinations of cultivars and mixing ratios should be evaluated on a case-by-case basis

Integrated weed management in organic field pea and lentil

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The potential for inter-row cultivation in organic pulse production

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Organic production tools for field peas: are cultivar mixtures more competitive with weeds?

Non-Peer ReviewedWithin Saskatchewan’s organic industry there is a need for improved tools to minimize yield losses due to weeds. Cultivar mixtures may improve the ability of organic pulse crops to suppress weeds and maintain yields in the presence of weeds. While semileafless peas are known for their lodging resistance and high yield potential in the absence of weeds, conventional peas may provide better weed suppression and yield stability in the presence of weeds. A replicated field experiment was conducted at two organic field sites to test the hypothesis that cultivar mixtures of conventional and semileafless field pea would differ in weed suppression and yields. The experiment tested factorial combinations of five ratios of semileafless pea cultivar CDC Dakota and conventional cultivar CDC Sonata (0:100, 25:75, 50:50, 75:25, and 100:0, respectively), and two seeding rates (conventional and organic recommended). Plots were monitored for crop and weed emergence, biomass, and yields. Significant differences were observed among the different ratios of semileafless and conventional field pea. Results indicate that the semileafless cultivar was more competitive with weeds than the conventional. As the canopy composition progressed from a pure conventional canopy towards increasing percentages of semileafless pea in the mixture, total weed biomass decreased, and total crop yields increased. It was concluded that while no additional weed suppression or yield benefits were seen compared with growing the more strongly competitive semileafless cultivar alone, cultivar mixtures reduced the risk associated with growing unfamiliar or less competitive cultivars by stabilizing weed suppression and crop yields at a level between the two components of the mixture

Using overhead images to determine volume and ground cover of lentil (Lens culinaris Medik.)

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Can tillage and agronomy be integrated with herbicide application to control resistant weeds?

Non-Peer ReviewedThe prevalence of group 2 resistant broadleaved weeds threatens successful lentil production on the Canadian Great Plains. The objective of this study was to develop an integrated weed management strategy combining physical, cultural and chemical weed control methods for lentil producers dealing with group 2 resistant wild mustard. The study was conducted for 3 years between 2011 and 2013 at 2 locations at Saskatoon and Scott, Saskatchewan. It was a randomized two way factorial with weed control method and seeding rate as the main effects. Weed control treatments tested consisted of a control treated with a glyphosate burnoff, saflufenacil (Heat ™) herbicide, rotary hoeing, half rate metribuzin (Sencor ™) herbicide, a fully integrated treatment, and a full herbicide treatment. Three seeding rates representing 1, 2, and 4 times the recommended seeding rate were tested (130, 260, and 520 plants m-2). Increasing seeding rate consistently lowered mustard biomass at both locations. The full herbicide treatment provided the greatest reduction in mustard biomass followed by the integrated treatment. The integrated treatment relied more on increased seeding rate to reduce mustard biomass and produce yield, and at the highest seeding rate it was able to provide equivalent yield to the full herbicide system. The results of this study show that an integrated system utilizing an increased seeding rate can control resistant weeds and maintain yields to a similar level as a strategy that relies only on herbicides for weed control

Utilizing deep learning to predict the number of panicles in wheat (triticum aestivum)

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The impact of DCD and NBPT concentration on nitrification and volatilization

Non-Peer ReviewedNitrification inhibitors are used in agriculture to slow the conversion of ammonium to nitrate by inhibiting ammonia monoxygenace (AMO), which is found within the Nitrosomonas bacteria. There are two ways to inhibit nitrification of the AMO enzyme, namely, (a) competitive inhibition: The inhibitor will compete to occupy AMO's active site; by blocking the active site, it slows the conversion of ammonium to nitrate preventing loss of nitrates, and, (b) non-competitive inhibition: The inhibitor can temporarily inactivate the AMO enzyme by altering the active site. Dicyandiamide (DCD) is a competitive inhibitor. The amount of DCD delivered by a product has a direct impact on how well a product will inhibit loss of nitrogen through nitrification. Research shows the concentration of DCD in the soil has a direct influence on the percent of nitrification. Higher concentrations of DCD equate to higher percentage of nitrification inhibition. The results of a two-year program that compares two products, one containing 8500 ppm and one 870ppm of DCD and approximately equal concentration of a volatilization inhibitor will be presented

Evaluating the competitive ability of semi-leafless field pea cultivars

Non-Peer ReviewedField pea (Pisum sativum L.) is an important grain legume in Western Canada. Growers can, however, be reluctant to include pulse crops in their rotation because they are poor competitors with weeds. Developing more competitive field pea cultivars is important to mitigate weed competition. The identification of competitive cultivars and the traits conferring competitive ability should lead to the development of more competitive field pea cultivars. The objective of this research was to evaluate the ability of semi-leafless field pea cultivars to suppress and withstand weed competition and to identify traits that may confer competitive ability in field pea. Field experiments were conducted in 2012 and 2013 at Floral, Saskatchewan, Saskatoon, Saskatchewan and St. Albert, Alberta. Fourteen semi-leafless field pea cultivars were seeded at a target density of 75 plants m-2 under weedy and weed-free conditions. Imidazolinone-tolerant wheat (c.v. CDC Imagine) and canola (c.v. 45H73) were planted as pseudo weeds in the weedy plots. There was no cultivar by treatment interaction for all of the measured variables thus, cultivars did not differ in the presence or absence of weed competition. CDC Dakota produced the greatest pea yield and Reward produced the poorest pea yield at Saskatchewan. CDC Dakota and CDC Striker were among the best for pea biomass production at Saskatchewan, compared to Reward, which was among the worst. CDC Centennial and CDC Mozart were significantly better at Saskatchewan for their ability to withstand competition, while CDC Dakota, CDC Patrick, and CDC Meadow were statistically the best in their ability to compete with the pseudo weeds. At Alberta, CDC Striker and CDC Dakota were statistically best in their ability to compete with the pseudo weeds, versus Cooper and Stratus, who were among the poorest. At both Saskatchewan and Alberta, no correlations were strong enough to show which traits are conferring competitiveness in semi-leafless field pea cultivars

Bean quest 2002: the final frontier

Non-Peer ReviewedThe agronomic, economic and genetic pieces of the jigsaw puzzle for developing a dryland bean industry in Saskatchewan are coming together. In 2002, dryland bean growers in Southeastern Saskatchewan made a profit using new varieties of black and pinto bean. Much of the credit for this goes to the hard work, homework, and perseverance of the crop clubs that have developed around the province in the past few years. The research and development effort of the past 10 years is finally starting to pay dividends in the dry bean sector of the pulse industry. In this paper, we would like to briefly summarize some of the key results of various dry bean research and development projects that have been underway in the past few years