Some effects of leaf area control on the yield of wheat

Abstract

The effects on var. Olympic wheat of maintaining the leaf area index (LAI), once attained, at approximately 3 and 1, and of removing all leaves or half of each leaf at ear emergence, were assessed by comparison with an uncut crop (maximum LAI = 12). Leaf stripping at ear emergence had no significant effect on grain yield. Leaf area maintenance at LAI values of 3 and 1 greatly decreased grain yield by reducing both grain number per spikelet and mean grain weight by about 50%. These effects followed earlier reductions in the rate of development of the shoot apex. The results are discussed in relation to the yields obtained and conclusions reached by English workers, and to possible scope for yield improvement.