熟相是指棉株吐絮成熟期的衰老表现,有正常成熟、早衰和贪青晚熟等熟相之分,实现正常熟相需要协调的库源关系和根冠关系.整枝、嫁接和环割等措施通过改变棉花库源关系和根冠关系,导致细胞分裂素和脱落酸含量发生变化,引起早衰或贪青晚熟等异常熟相.品种自身的遗传背景、栽培措施和外界环境等都可以改变库源关系、根冠关系及相关的植物激素平衡,从而影响棉花熟相.受渗透胁迫、离子毒害和营养障碍等因素的影响,滨海盐碱地棉花容易出现库源关系和根冠关系失调,引起早衰或贪青晚熟等异常熟相,并导致棉花产量和纤维质量下降.本文提出,选用对路品种,不断改良培肥盐碱地减轻盐离子毒害和营养障碍,合理密植、科学整枝和适时适度化控,是滨海盐碱地棉花获得正常熟相、优质高产的有效途径.%Maturity performance is termed as senescence performance of a cotton plant during boll opening. Normal maturity per-formance is obtained only when sink-source and root-canopy is well coordinated. A number of experiments have been conducted to confirm that removal of branches, seedling grafting and stem girding at squaring change sink-source, root-canopy and car-bon-nitrogen metabolism. The cytokinins and abscisic acid (ABA) changed accordingly, thus leading to premature senescence or late-maturity performance of cotton. Cultivar itself, cultivation measures, and external environment can also affect cotton maturi-ty performance through modifying sink-source and root-shoot relations, and hormone metabolism. Our results have shown that in coastal saline soils, salinity stress and nutritional disorders often lead to sink-source and root-canopy relation imbalance and pre-mature senescence or late-maturity performance of cotton, and thus reduce cotton yield and fiber quality. This paper summarizes and reveals the effects and the underlying mechanisms of cultivar itself, cultivation measures, and external environment on sink-source and root-shoot relation and hormone metabolism. It is suggested that utilization of suitable cultivar, improvement of fertility of saline fields, rational pruning, increasing plant density, and proper chemical regulation are effective practices to obtain normal maturity performance and to increase yield of cotton in saline fields.
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