COMPENSATORY GROWTH IN COTTON AFTER LOSS OF REPRODUCTIVE-ORGANS

Sustainable cotton production requires pest management systems that en hance the role of natural regulatory mechanisms. One such mechanism is compensatory growth, the subject of this review. Current hypotheses t o explain compensatory growth of cotton after the loss of reproductive structures place emphasis on yield components and consider only to li mited extent source/sink relationships for carbon. The aim of this rev iew is to integrate into these hypotheses, mechanisms accounting for o ther physiological and morphological changes induced by loss of reprod uctive-structures. This paper (a) summarises the current hypotheses to explain cotton yield compensation for pest damage affecting reproduct ive organs, (b) analyses the nutritional and hormonal hypotheses of co ordination of growth on the grounds that fruit loss strongly affects t he economies of carbon and nitrogen as well as the balance of plant-gr owth regulators, (c) presents the hypothesis that actual yield respons es will depend on the combined effects of fruit loss on yield potentia l (as affected by changes in acquisition and partitioning of carbon an d nitrogen), and on growing conditions (as affected by changes in the spatial pattern on the plant and seasonal timing of fruiting). This hy pothesis could provide a framework for experimental and simulation stu dies on yield compensation in cotton.