Heat stress influences dormancy in peanut seeds (arachis hypogea l)

Abstract

Peanut is one of the annual crops grown in both arid and semi arid areas whose germination can be affected by high temperatures. The effect of heat stress on seed germination and seedling vigor was investigated. Seeds were kept in sealed laminated aluminium foil bags and exposed to heat stress for 48 h at four temperatures; 27±2°C, 70±5% RH (control: room temperature), 40°C, 50°C, and 60°C. Seed germination and seed vigor decreased significantly as the heat stress temperature increased. The seed moisture content and total abnormal seedlings did not vary among treatments whereas occurrence of deformed seedlings was significant at temperatures greater than 40±1°C. However, 40°C significantly induced dormancy by 31% compared to the control seeds, while heat stress beyond 50°C had detrimental effect on peanut seeds in the form of embryonic death.