Comparing Brassica oilseed crop productivity under contrasting N fertility regimes in the semiarid northern Great Plains

. 2008. The Biology of Canadian Weeds. 137. Brassica napus L. and B. rapa. Can. J. Plan Sci. 88: 951Á996. Brassica napus and B. rapa are native to Eurasia. In Canada, these species are commonly referred to as volunteer canola, while feral populations of B. rapa are referred to as birdrape. Brassica napus and B. rapa have been grown commercially for their seed oil content in western Canada since the middle of the last century and volunteer populations are common in fields. Escaped populations of both species are also found along roadways, railways and in waste areas; however, only B. rapa is known to have naturalized, self-sustaining feral populations in these habitats in eastern Canada. Despite these escaped and feral populations, B. napus and B. rapa are mainly a concern in agricultural fields where their combined relative abundance has increased over the past few decades. In the mid 1990s, herbicideresistant genotypes of B. napus were released for commercial production. Herbicide-resistance and the stacking of genes in volunteer populations conferring resistance to multiple herbicides have contributed to increased difficulties in controlling volunteer B. napus in some crops. However, yield loss resulting from volunteer populations is not well documented in Canada.Key words: Brassica napus, Brassica rapa, herbicide resistance, transgene escape, volunteer canola, weed biology Gulden, R. H., Warwick, S. I. et Thomas, A. G. 2008. La biologie des mauvaises herbes au Canada. 137. Brassica napus L. et B. rapa L. Can. J. Plant Sci. 88: 951Á996. Brassica napus et B. rapa sont des plantes originaires d'Eurasie. Au Canada, on les de´signe souvent sous l'expression « canola spontane´», tandis que les peuplements sauvages de B. rapa sont appele´s « navette ». Dans l'Ouest canadien, Brassica napus et B. rapa sont cultive´s commercialement pour l'huile que renferment leurs graines depuis le milieu du sie`cle dernier et les repousses spontane´es sont devenues monnaie courante dans les champs. On observe des peuplements des deux espe`ces le long des routes et des voies ferre´es ainsi que dans les terrains vagues, cependant on sait que seule B. rapa s'est acclimate´e pour donner des populations sauvages et stables dans les meˆmes habitats, dans l'est du pays. Malgre´cela, B. napus et B. rapa demeurent surtout pre´occupants dans les cultures, oul eur abondance relative, une fois combine´s, s'est accrue au cours des dernie`res de´cennies. Au milieu des anne´e 1990, des ge´notypes de B. napus re´sistants aux herbicides ont e´te´homologue´s pour la culture commerciale. Cette re´sistance et l'accumulation des ge`nes qui la codent dans les peuplements spontane´s ont concouru a`compliquer la lutte contre les repousses de B. napus dans certaines cultures. Quoi qu'il en soit, les pertes de rendement qui en re´sultent sont mal e´taye´es au Canada.

Section: Population Dynamicsmentioning

confidence: 99%

“…As a crop in Turkey, B. rapa had 217 and 404 pods plant (1 with 10 to 11 seeds pod (1 , resulting in stable seed production over planting densities ranging from 50 to 800 seeds m (2 (Bilgili et al 2003). Seed production in domesticated B. rapa tends to be lower than in domesticated B. napus (Miller et al 2003).…”

Section: Historymentioning

confidence: 99%

The Biology of Canadian Weeds. 137. Brassica napus L. and B. rapa L.

Gulden¹,

Warwick²,

Thomas³

2008

“…However, further research on the interaction of fertilizer N rate and stubble management is needed to revise fertilizer recommendations for canola grown in the semiarid prairie. Canola and mustard grown in the semiarid prairie can respond to higher levels of N under favorable moisture conditions (Miller et al 2003). Canola grown in tall stubble with extra fertilizer tended to use the most water and had the highest HI, and, indeed, used more water and had a higher HI than canola grown in stubble cultivated the previous fall [cultivated (fall) stubble].…”

Section: Figmentioning

confidence: 99%

Stubble management and microclimate, yield and water use efficiency of canola grown in the semiarid Canadian prairie

Cutforth¹,

Angadi²,

McConkey³

2006

Self Cite

Cutforth, H. W., Angadi, S. V. and McConkey, B. G. 2006. Stubble management and microclimate, yield and water use efficiency of canola grown in the semiarid Canadian prairie. Can. J. Plant Sci. 86: 99-107. Standing stubble traps snow and creates a favorable microclimate, which increases yields in wheat (Triticum aestivum L.) and pulses [chickpea (Cicer arietinum L.), field pea (Pisum sativum L.) and lentil (Lens culinaris L.)]. Generally, the taller the stubble the greater is the effect on microclimate and yield. A field study using farm-scale seeding and harvesting equipment was conducted over four seasons (1999 to 2002) to assess the effect of stubble management on the microclimate, water use and seed yield of argentine canola (Brassica napus L. 'Arrow') in the semiarid prairie surrounding Swift Current. Tall (30 cm), short (15 cm) and cultivated stubble treatments were deployed in fall and in spring. An additional tall stubble treatment with extra fertilizer N (application rate recommended for the Black soil zone in the subhumid prairie) was included to assess the role of fertilizer in canola response to stubble management practices. The differences in wind velocity, soil temperature and solar radiation reaching the soil surface indicated significant modification of the microclimate by tall compared with cultivated stubble. Yields were highest from the tall stubble receiving extra fertilizer. Further research is needed to determine optimum fertilizer rates to maximize canola yields in the semiarid prairie. For treatments receiving equivalent rates of fertilizer, tall stubble increased seed yield of canola by about 24% and water use efficiency (WUE) by about 19% compared with stubble cultivated in the fall. Comparing between stubble treatments deployed on fields that overwintered as tall stubble and which received equivalent rates of fertilizer, tall stubble increased canola yield by about 16% and WUE by about 11% compared with cultivated stubble. Crop water use was not affected by stubble management so the increased grain production was due to increased WUE. . En général, plus haut est le chaume, meilleurs sont ses effets sur le microclimat et le rendement. Les auteurs ont procédé à une étude sur le terrain en recourant à de l'équipement commercial pour les semis et la récolte; l'étude a duré quatre saisons (de 1999 à 2002) et devait servir à évaluer l'incidence de la gestion du chaume sur le microclimat, l'utilisation de l'eau et le rendement grainier du canola argentin (Brassica napus L. cv Arrow) dans la région semi-aride des Prairies qui entoure Swift Current. À cette fin, les auteurs ont recouru à du chaume élevé (30 cm), du chaume court (15 cm) et du chaume cultivé à l'automne et au printemps. Ils ont aussi examiné un autre traitement consistant en du chaume élevé avec application d'engrais N supplémentaire (au taux recommandé pour les sols noirs dans la zone sub-humide des Prairies) de manière à évaluer le rôle de l'engrais dans la réaction du canola aux pratiques de gestion du chaume. Les variations...

“…When well-watered, B. napus used less water than wheat (Table 5). Because available soil water within the rooting zone is an important contributor to crop yield, and because crops tend to use much or all the available water within the rooting zone under the water-limited conditions of the semiarid prairie, deeper-rooted crops such as Brassica oilseeds and wheat tend to use similar amounts of water, while shallower rooted crops such as pea and lentil use slightly less water (Merrill et al 2002;Miller et al 2003b;Miller and Holmes 2005).…”

Section: Seeding Datementioning

confidence: 99%

“…Among Brassica oilseeds, mustard was reported to be more heat and water stress (drought) tolerant than canola (Woods et al 1991;Good and MacLagan 1993;Wright et al 1996;Angadi et al 2000;Oram et al 2005). Cutlass oriental mustard was consistently the highest yielding Brassica oilseed grown in a field study conducted during 1996Á1998 in the semiarid prairie of southwestern Saskatchewan (Miller et al 2003a). As well, in a field study from 2003 to 2005 in the moist black soil zone of northeastern Saskatchewan, Cutlass was the highest yielding Brassica in a dry year, but not in years when growing season precipitation was above-average (Malhi et al 2007).…”

mentioning

confidence: 99%

Adaptation of alternative pulse and oilseed crops to the semiarid Canadian Prairie: Seed yield and water use efficiency

Angadi¹,

McConkey²,

Cutforth³

et al. 2008

Self Cite

. 2008. Adaptation of alternative pulse and oilseed crops to the semiarid Canadian Prairie: Seed yield and water use efficiency. Can. J. Plant Sci. 88: 425Á438. Diversification and intensification of the cropping systems in the traditional wheat-fallow area of the semiarid Canadian prairie is necessary to improve sustainability. Selection of alternate crops to include in cropping systems requires information on production risks with different climate regimes. To understand water use/yield relationships of alternate crops, three pulse crops (leguminous grain crops) [chickpea (Cicer arietinum L.), pea (Pisum sativum L.) and lentil (Lens culinaris Medik.)], three oilseed crops [canola (Brassica napus L. and B. rapa L.) and mustard (B. juncea L.)], and one cereal crop [wheat (Triticum aestivum L.)] were studied under varying water regimes: during 1996Á1998 under well-watered, rainfed, imposed drought conditions, and in 2001 under rainfed conditions. Generally, the relative ranking between crops for water use was maintained across water regimes, such that the crops separated into three general groups of water users (high: wheat, B. napus, mustard; medium: chickpea, B. rapa, lentil; low: pea) with pea using an average of 34 mm and 13 mm less water than high-and medium-water-using crop groups, respectively. The exceptions included desi chickpea, which tended to use less water and B. rapa, which tended to use more water relative to the other crops as water use decreased. Generally, pea and wheat produced the most grain and biomass, had the highest water use efficiency, and had moderately high to high harvest indices. Wheat and pea are well adapted to variable rainfall amounts inherent in semiarid climates. Desi chickpea and lentil produce good grain yields under dry conditions, and grain yields relative to those of other crops can be increased by some drought stress, especially mid-to lateseason stress. Therefore, because of their relatively good performance under water-stressed conditions, they are also well adapted to semiarid climates. Conversely, the Brassica oilseeds yielded relatively poorly compared with wheat and pulse crops under severe water-stressed conditions, so they are not as well adapted to the semiarid climate. In 2001, grain yield of wheat and pulses seeded on stubble was ]30% of the yield on fallow, whereas stubble-seeded Brassica oilseeds yielded only about 10% of that on fallow. Compared with stubble seeding, production of Brassica oilseeds on fallow will decrease the risk of very low yields under drought. We found little indication that mustard was more drought tolerant than B. napus.