Up to 32 % yield increase with optimized spatial patterns of canola plant establishment in western Canada

Abstract

International audienceCanola—Brassica napus L.—is an economically major crop in many parts of the world. The seed yield of canola is often limited by poor plant establishment. This issue is serious in areas with short growing seasons, such as western Canada, where canola plants have a limited time span plasticity to adapt and compensate for yield losses due to poor or non-uniform plant establishment. The effect of spatial patterns of canola plant stands on seed yield is actually unknown. Therefore, we studied the impacts of uniformity of plant stands on pod formation, seed set, and crop yield of canola. Field experiments were conducted at 16 site-years across the different soil-climatic zones of the Canadian prairies. At each site-year, the cultivar InVigor® 5440, a glufosinate-resistant hybrid, was sown at 100, 80, 60, 40, and 20 plants per square meter with uniform and non-uniform stands. We found that spatially uniform stands increased seed yield by up to 32 % at low-yielding sites and by up to 20 % at the high-yielding sites compared to non-uniform plant stands. This effect is mainly due to increased number of fertile pods. The yield increase was more pronounced with plant densities lower than 60 plants per square meter. Also, canola seed yield depended largely on plant survival during the hot summer and was less affected by the rate of seedling emergence. We conclude that canola yield can be increased by improving the uniformity of plant spatial distribution patterns in the field regardless of environmental conditions

Canola seed yield and phenological responses to plant density

“…Percent emergence was calculated and expressed as number of plants emerged divided by number of seeds planted, per unit area. Overall, the actual percent plant emergence closely matched the target plant density at each site-year, and the emergence data were discussed in a previous report (Yang et al 2014).…”

“…At high-yield sites, adequate to excessive fertility may have limited interplant competition for nutrients. Previous studies have shown that with high soil fertility, canola plants typically branch vigorously (Harker et al 2015a), with more fertile pods produced per plant (Yang et al 2014). In contrast, strong plant plasticity was not observed at sites with moderate or low soil fertility (Tables 1 and 2).…”

“…In contrast, strong plant plasticity was not observed at sites with moderate or low soil fertility (Tables 1 and 2). With limited soil nutrients coupled with drought and heat stresses typical at Swift Current, the production of branches and fertile pods per unit area may be limited (Gan et al 2007;Yang et al 2014).…”

Evaluation of the Causes of On‐Farm Harvest Losses in Canola in the Northern Great Plains

“…High density stands also mature earlier and more evenly (Irvine and Lafond, 2010) which facilitates harvest management. The study by Yang et al (2014) that described the important contribution of canola stand uniformity on yield, unfortunately, did not measure harvest losses. Producers report canola seeding rates based on the weight of total seed planted per unit area (i.e., kg ha -1 ) rather than seed densities per unit area and do not account for differences in seed size.…”

“…Early maturation is linked to early planting and early planting of B. napus has been linked to high canola yields as the crop avoids high temperatures during anthesis (Kirkland and Johnson, 2000). High canola stand densities and uniformity are critical for achieving high yields (Yang et al, 2014). High density stands also mature earlier and more evenly (Irvine and Lafond, 2010) which facilitates harvest management.…”