雹灾后施氮配合中耕对棉花14C同化物生产及运转分配的影响

运用＾１５Ｎ和＾１４Ｃ示踪技术,研究了雹灾后施氮配合中耕对棉株吸氮动态,吸氮量,＾１４Ｃ同化物生产及运转分配的影响。研究结果表明,蕾期遭受雹灾后及对施氮并配合中耕,可使棉株开始吸收肥料氮的时间提前,棉株吸氮量、含氮量和肥料利用率也显著提高。棉株花铃期的相对光合作用强度（以放射性比强表示）和＾１４ＣＯ２同化量均显著高于单纯施氮处理和对照。而且,棉株的同化产物以较大的比例转运至生殖器官特别是成铃中,并

Effect of N Application Combined with Hoeing on the ~(14)CO_2-Assimilation and Partitioning of ~(14)C Assimilates within the Cotton Plants after Hailing Damage

Using 15N and 14C tracing technique, the effect of N application combined withhoeing on the uptake of N, production and partitioning of 14C assimilates within cotton plant after hailing damage occuring at squaring stage were investigated. It was showed that cotton plantbegan to absorb N from fertilizer after hailing damage eariler than no hoeing treatment, in response to N application hoeing and the total amount of N absorbed, N concentration and fertilizer utilization efficiency of cotton plant were increased significantly. As a result, the 14CO2 assimilation of cotton plant at flowering and fruiting stage was markedly higher than control and nohoeing treatment. Moreover, the partitioning of 14C assimilates into bolls and seed cotton wereincreased greatly, resulting in significant increase of boll number per hectar, lint yield and pre-frost lint.