喷施细胞分裂素对豇豆花荚脱落率及花荚酶活性的影响

以4个豇豆(Vigna unguiculata Linn.)品种‘鄂豇豆6号’、‘鄂豇豆2号’、‘鄂豇豆7号’和‘美国地豆’为材料,在现蕾期叶面喷施植物细胞分裂素(CTK),于喷施后第7、14、28、42 d测定脱落花荚的多聚半乳糖醛酸酶(PG)和纤维素酶活性,并统计花荚脱落率和豇豆产量,研究CTK在豇豆生长发育过程中对花荚脱落的影响。结果显示,喷施CTK后,豇豆各品种的花荚脱落率均小于对照,豇豆产量均高于对照,且差异极显著(P0.01);喷施CTK后第14、28、42 d豇豆各品种脱落花荚的PG活性显著降低(P0.05);喷施CTK后第7 d各处理组脱落花荚的PG活性极显著降低(P0.01);喷施CTK后第7 d和第42 d豇豆各品种脱落花荚的纤维素酶活性显著降低(P0.05),喷施CTK后第14 d和第28 d各处理组脱落花荚的纤维素酶活性极显著降低(P0.01)。研究结果表明喷施CTK可调节脱落花荚的PG活性和纤维素酶活性,从而降低花荚脱落率,实现对豇豆产量的调控。

Effects of Spraying Cytokinin on Abscission Rate and Enzymic Activity of Flowers and Pods of Cowpea

Four cowpea varieties, ‘E Jiangdou 2’, ‘E Jiangdou 6’, ‘E Jiangdou 7’, and ‘Meiguo Didou’, provided by the Hubei Province Engineering Research Center were selected as research materials. We sprayed cytokinin on leaves in budding stage to study its effects on the abscission of flowers and pods in the field. At 7, 14, 28 and 42 d after spraying, we analyzed the yields and abscission rates of flowers and pods, and detected the enzyme activities of polygalacturonase and cellulase in premature shedding of flowers and pods.Results showed that after spraying cytokinin, the abscission rates of flowers and pods in different cultivars were lower than those in the control, but yields in different cultivars were higher, with the differences being highly significant (P < 0.01). Furthermore, the polyga-lacturonase activities of cowpea were significantly lower than those of the control at 14 d, 28 d and 42 d after spraying (P < 0.05), and significantly lower at 7 d after spraying (P < 0.01). The cellulase activities of fallen flowers and pods were significantly (P < 0.05) lower than those of the control at 7 d and 42 d after spraying, and significantly (P < 0.01) lower at 14 d and 28 d after spraying. The above results indicated that the activities of polygalacturonase and cellulase were regulated by spraying cytokinin, which resulted in reducing the abscission rate of flowers and pods and regulating yield in cowpea.