Controlling indeterminate lentil crop growth through nitrogen supply

通过氮供应控制不确定的扁豆作物生长

• 批准号: 349011-2006
• 负责人: Bueckert, Rosalind
• 金额: $ 5.59万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Agriculture and Agri-Food Canada Research Partnership
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=401756
• 关键词: Controlling; indeterminate; lentil; crop; growth

Lentil is an indeterminate pulse crop, which means it has a growth habit where vegetative growth continues during reproductive growth. In contrast, the determinate habit has a vegetative phase followed by a distinct switch to reproductive growth, for example, in grasses. In wet years and when it has a high nitrogen (N) supply, lentil fails to mature in the short growing season on the Prairies, resulting in low unstable yields. Because a determinate lentil genotype has not yet been found, we believe an agronomic approach of controlh'ng the balance between vegetative and reproductive growth through crop N supply may provide a solution to this delayed maturity. On the Prairies, the indeterminate habit is managed by relying on either a terminal stress (drought, frost, lack of N) or chemical desiccation to cease growth. Lentil can derive most of its N through biological N fixation, a symbiotic relationship between rhizobia bacteria and the plant that takes place in nodules on the roots. Lentil can also use fertilizer N, or soil supplied N through the process of soil mineralization. Growers depend on N fixation, but soil inorganic N may be available depending on the previous soil history, climate and mineralization. In this research, we plan to investigate how lentil indeterminacy can be managed by four strategies. The first is to test if lentil maturity can be controlled by soil N supply in zero tillage and conventional tillage soils. The second is to test if a desiccant at low concentrations can trigger senescence and maturity under high N conditions. The third strategy is test if nine lentil genotypes that are commercially grown vary in N uptake, N fixation, or N redistribution within the plant during reproductive growth. Finally, the fourth strategy is to identify earlier senescing rhizobia strains so N fixation will only occur up to mid-reproductive growth. Together, all these strategies will give us a detailed understanding of how N is partitioned in lentil in order to have satisfactory crop maturity.

小扁豆是一种不确定的豆类作物，这意味着它具有在生殖生长期间继续营养生长的生长习性。相比之下，决定性习性有一个营养生长阶段，随后明显转向生殖生长，例如草类。在潮湿的年份，当氮 (N) 供应量较高时，大草原上的扁豆在较短的生长季节内无法成熟，导致产量低且不稳定。由于尚未发现确定的扁豆基因型，我们相信通过作物氮供应控制营养生长和生殖生长之间平衡的农艺方法可能会为这种延迟成熟提供解决方案。在大草原上，这种不确定的习性是通过依靠最终压力（干旱、霜冻、缺氮）或化学干燥来停止生长来控制的。小扁豆可以通过生物固氮获得大部分氮，这是根瘤菌和植物之间在根部根瘤中发生的共生关系。小扁豆还可以使用肥料氮，或通过土壤矿化过程提供的土壤氮。种植者依赖于固氮，但土壤无机氮的可用性取决于之前的土壤历史、气候和矿化程度。在这项研究中，我们计划研究如何通过四种策略来管理扁豆不确定性。首先是测试零耕和常规耕作土壤中的氮供应是否可以控制扁豆成熟度。第二个是测试低浓度的干燥剂是否可以在高氮条件下引发衰老和成熟。第三个策略是测试商业种植的九种扁豆基因型在生殖生长期间植物内的氮吸收、氮固定或氮再分配方面是否存在差异。最后，第四个策略是识别较早衰老的根瘤菌菌株，因此氮固定只会发生到繁殖生长中期。总之，所有这些策略将使我们详细了解氮在扁豆中的分配方式，以获得令人满意的作物成熟度。