COMPENSATORY GROWTH IN COTTON AFTER LOSS OF REPRODUCTIVE-ORGANS

Sustainable cotton production requires pest management systems that enhance the role of natural regulatory mechanisms. One such mechanism is compensatory growth, the subject of this review. Current hypotheses to explain compensatory growth of cotton after the loss of reproductive structures place emphasis on yield components and consider only to limited extent source/sink relationships for carbon. The aim of this review is to integrate into these hypotheses, mechanisms accounting for other physiological and morphological changes induced by loss of reproductive-structures. This paper (a) summarises the current hypotheses to explain cotton yield compensation for pest damage affecting reproductive organs, (b) analyses the nutritional and hormonal hypotheses of coordination of growth on the grounds that fruit loss strongly affects the economies of carbon and nitrogen as well as the balance of plant-growth regulators, (c) presents the hypothesis that actual yield responses will depend on the combined effects of fruit loss on yield potential (as affected by changes in acquisition and partitioning of carbon and nitrogen), and on growing conditions (as affected by changes in the spatial pattern on the plant and seasonal timing of fruiting). This hypothesis could provide a framework for experimental and simulation studies on yield compensation in cotton.