The effect of seeding rate and fungicide applications on lentil cultivars

ABSTRACT Recent research has shown that yield potential of lentil can be increased. Lentil (Lens culinaris Medik.) is one of the least competitive crops grown on the Canadian prairies. Additional drawbacks to lentil production include susceptibility to disease and lack of knowledge for optimal seeding rates. Yield-density studies elucidate a specific crop’s ability to maximize field resources, and current literature suggests that lentil seeding rates should be increased to raise yield potential, notably under weedy conditions. However, disease pressure is of concern when lentil plant populations are elevated, so a balance is necessary. The objective of this research was to determine the effect of plant population on grain yield of different market classes of lentil, and to evaluate the interaction of disease control and seeding rate in different lentil market classes. To determine this, two field experiments were conducted in 2015 and 2016, in Saskatchewan, Canada. The first study involved six lentil cultivars and five seeding rates, while effects and interactions among them were examined. The second experiment involved the effect of four fungicide treatments, two seeding rates, and three red lentil cultivars. In the first experiment, the maximum yield was reached for all varieties at a seeding rate between 160 to 220 plants m-2. In the second experiment, the highest yield was accomplished at a rate that achieved a target plant population of 240 plants m-2 paired with two fungicide applications (Headline® and Bravo®). This treatment yielded statistically higher than both treatments that included only a single fungicide application. The treatment with Headline plus Bravo also contributed to the lowest overall visual disease severity rating in 2016, compared to all other treatments. These results, reinforced by previous studies with similar conclusions, establish that the current recommendation in Saskatchewan of 130 lentil plants m-2 is likely insufficient for obtaining maximum seed yield