不同时期PGRs对大豆花荚脱落率及纤维素酶活性的影响

在大田条件下，以合丰50大豆（Glycinemax）为材料，比较研究了在V3、R1和R3期叶面喷施三碘苯甲酸（TIBA）、烯效唑（S3307）和2-N，N-二乙氨基乙基己酸酯（DTA-6）三种植物生长调节剂（Plantgrowthregulators，PGRs）对大豆花荚脱落率纤维素酶活性的影响。结果表明：在V3、R1和R3期叶面喷施植物生长调节剂降低了大豆花荚脱落率；V3期叶喷TIBA、S3307、DTA降低了大豆花荚和脱落花荚纤维素酶活性，但对花的作用效果不显著；R1期PGRs显著降低了大豆花荚及脱落花荚的纤维素酶活性，以DTA调控效果最佳，S3307次之；R3期叶喷PGRs降低了大豆荚及落荚的纤维素酶活性，以TIBA调控效果最佳，S3307次之。综合分析表明，V3、R1和R3叶面喷施植物生长调节剂能够降低大豆花荚脱落率和纤维素酶活性，促进大豆花荚的建成，有利于提高产量，综合调控效果为V3期：S3307〉DTA〉TIBA〉CK；R1期：DTA〉TIBA〉S3307〉CK；R3期：TIBA〉S3307〉DTA〉CK。S3307最佳喷施时期为V3期；DTA最佳喷施时期为R1期；TIBA最佳喷施时期为R3期。

Regulation of plant growth regulators on abscission rate and cellulase activity of soybean flowers and pods

To study the effects of three plant growth regulators on abscission and cellulase activities of soybean flowers and pods in field, TIBA, S3307, DTA were sprayed on leaves during V3, R1 and R3 stages. Hefeng 50 （ Gly- cine max （ L. ） Merr. ） was selected as the material. The results showed that abscission rate of soybean flowers and pods decreased after spraying TIBA, S3307 and DTA in all the stages. The cellulase activities of flowers and pods decreased after spaying TIBA, S3307and DTA in V3 stage. The effect was not significant on flowers. PGRs decreased cellulase activity significantly if sprayed at R1 stage, the regulation effect of DTA was the best. PGRs decreased ab- scission cellulase activity in pod and abscission pod if the spraying was at R3 stage, the regulation effect of TIBA was the best. The analysis showed that PGRs decreased cellulase activity, promoted development of flowers and pods at V3 ,R1 and R3 stages, which further increased production. The overall regulation effect was S3307 〉 DTA 〉 TIBA 〉 CK in V3 stage ; DTA 〉 TIBA 〉 S3307 〉 CK in R1 stage ; TIBA 〉 S3307 〉 DTA 〉 CK in R3 stage. V3 stage was the best stage for spraying 53307 ; R1 stage was the best stage for spaying DTA; R3 stage was the best stage for spaying TIBA.