Controlling indeterminate lentil crop growth through nitrogen supply

小扁豆是一种不确定的豆类作物，这意味着它有一种生长习性，即在生殖生长期间继续营养生长。相反，有限的习惯有一个营养阶段，然后是一个明显的转换到生殖生长，例如，在草。在潮湿的年份，当它有高氮（N）供应时，小扁豆不能在草原上的短生长季节成熟，导致产量低而不稳定。由于尚未发现确定的小扁豆基因型，我们相信通过作物氮供应来控制营养生长和生殖生长之间的平衡的农艺方法可能提供这种延迟成熟的解决方案。在大草原上，不确定的习惯是通过依赖于终端应力（干旱，霜冻，缺乏N）或化学干燥停止生长来管理的。小扁豆可以通过生物固氮获得大部分的氮，这是根瘤菌和植物之间的共生关系，发生在根部的根瘤中。小扁豆也可以使用肥料N，或通过土壤矿化过程提供的土壤N。种植者依赖于氮固定，但土壤无机氮可能取决于以前的土壤历史，气候和矿化。在这项研究中，我们计划研究如何扁豆不确定性可以管理的四个策略。第一个是测试小扁豆成熟度是否可以控制土壤氮供应在免耕和常规耕作土壤。第二是测试低浓度的干燥剂是否能在高氮条件下引发衰老和成熟。第三个策略是测试九种商业种植的小扁豆基因型在生殖生长过程中的氮吸收、氮固定或氮再分配是否不同。最后，第四个策略是识别更早衰老的根瘤菌菌株，使固氮只发生在中期生殖生长。总之，所有这些策略将使我们详细了解氮是如何在扁豆中分配的，以获得令人满意的作物成熟度。

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.