Effect of soil temperature alteration by soil covers on seedling emergence of wheat (Triticum aestivum L.) sown on two dates

Summary

A field study was conducted to evaluate the effect of soil temperature altered by various ways of soil coveringviz control (T₁), transparent polyethylene (T₂), black polyethylene (T₃), rice straw (T₄), rice straw applied only during night (T₅) and farm yard manure (T₆) on seedling emergence of wheat sown on November 30, 1978 and January 6, 1979. Maximum increase in soil temperature occurred under transparent polyethylene cover. Temperature alterations were relatively smaller under other treatments and was minimum under farm yard manure cover. With both sowings, the effect of various ways of soil covering on seedling emergence depended on the magnitude of soil temperature alteration caused by them. It was hastened markedly under transparent polyethylene cover and only slightly under black polyethylene cover. Continuous soil covering with rice straw slowed down seedling emergence while covering only during night hastened it slightly. Farm yard manure cover showed negligible effect on seedling emergence. Seedling emergence response to an increase in soil temperature was higher with second sowing when temperature was relatively lower than with first sowing. The result suggests the possibility of expediting seedling emergence of wheat sown under low temperature condition by transparent polyethylene cover. Seedling emergence was only slightly influenced by other soil covers.