EFFECTS OF SUBSOILING ON PEANUT SUBJECTED TO WATER SHORTAGE AT DIFFERENT GROWTH STAGES

Abstract

Though most of the low land paddies in Chiang Mai - Lamphun Valley are irrigable land, croppings after rice during the dry season in the area are prone to water shortage, especially in March and April.

The water shortage should be more severe insoil with a plow pan. This experiment was aimed at evaluation of the results of subsoiling in lessening the adverse effects of water shortages at different growth stages of peanut. Water shortages were induced by witholding irrigation.

Results of the experiment on soil moisture content and peanut growth and yield did not show any effect of pan breaking. This might be due to the timing of pan breaking in early December, pan layer was too wet for effective shattering.

The water shortage during vegetative stage had relatively less effects in yield compressing to those at flowering and pod forming stages. Water shortage during the flowering stage caused 35% yield reduction when compared with well irrigated treatment. Water shortage during pod forming stage resulted in the delay of pod maturity for at least 10 days.

However, there were heavy rains during harvesting time, Thus, the soil in the root zone was completely wet. Harvesting of the peanut, subjected to the late water shortage was postponed for 10 days. The peanut yield in this treatment was slightly higher than that was subjected to water shortage during flowering stage.

The yields of peanuts subjected to water shortage at various growth stages

were highly correlated with the amount of irrigation water.