Effect of timing and intensity of drought on the growth and yield of field peas (Pisum sativumL.)

摘要

The response of field peas (Pisum sativumL.) to timing and intensity of drought was determined in an experiment in a mobile rainshelter, which excluded rainfall during growth of the crop. Twelve irrigation treatments subjected the crops to drought of varying duration at different stages during plant growth. Before and after the drought, the crops were fully irrigated. Pea seed yield decreased linearly as the maximum potential soil moisture deficit (Dpmax) experienced during the growth of the crop increased from 49 to 323 mm. The timing of Dpmaxdid not affect the decline in pea seed yield, but did affect the total dry matter (DM) produced by the crop. If Dpmaxoccurred before flowering, radiation interception and total DM yield were reduced more than if Dpmaxoccurred after flowering. However, this total yield reduction was completely offset by an increase in individual pea weight and consequently an increased harvest index. Pea seed yield was closely related to pod number per unit area, which was also strongly related to water stress. The number of peas per pod was unaffected by water stress.