The interaction between lodging and plant population in combining peas

SUMMARY The effects of preventing lodging in three varieties of combining peas with contrasting standing ability were studied over a range of plant populations and in two growing seasons. Maximal yield losses resulted when lodging occurred prior to the end of the flowering period. The likelihood of this event occurring was increased by high populations and was maximised when such populations were used in conjunction with conditions suitable for vigorous plant growth. In such seasons, optimum plant populations (30 plants m-2) were seen to be very much below those currently recommended. When conditions were less favourable to plant growth, lodging tended to occur after flowering had ceased. Little yield loss due to population effects were then recorded. Under such conditions, yields were maximised by high plant populations. Under all growing conditions, little yield loss due to interplant competition was noted with increasing plant populations. It was concluded from these results that if combining pea production is to be successfully expanded out of traditional production areas, plant population recommendations should be lowered to compensate for increased plant vigour.