【目的】探讨植物生长调节剂对大豆叶片和籽粒碳水化合物代谢及产量的影响,进一步从源库理论的角度挖掘调节剂增产的作用机理,为调节剂的应用提供依据。【方法】本研究于2013年和2014年在大田栽培条件下进行。以合丰50和垦丰16为材料,在始花期(R1期)叶面喷施60 mg·L~(-1)促进型调节剂2-N,N-二乙氨基乙基己酸酯(DTA-6)和50 mg·L~(-1)延缓型调节剂烯效唑(S3307),以喷施清水为对照(CK)。喷施调节剂后30 d开始第一次取样,以后每隔5 d取样一次,共取样5次。测定叶片和籽粒中蔗糖、淀粉、果糖含量及叶片中转化酶、蔗糖磷酸合酶(SPS)和蔗糖合酶(SS)活性。大豆成熟期测产。【结果】籽粒建成初期(喷施调节剂后30—35 d),S3307和DTA-6的叶片蔗糖、果糖和淀粉含量呈下降趋势;籽粒蔗糖、果糖和淀粉含量呈上升趋势,说明更多的碳水化合物用于籽粒的建成。籽粒建成中期(喷施调节剂后35—45 d),S3307的叶片蔗糖、果糖和淀粉含量一直呈上升趋势;S3307和DTA-6的籽粒蔗糖和果糖含量普遍高于CK,为籽粒灌浆提供了充分的物质保障。籽粒建成后期(喷施调节剂后50 d),S3307和DTA-6的叶片蔗糖含量达到最大,且与CK差异显著,S3307的叶片淀粉含量高于CK,DTA-6的叶片果糖含量高于CK;S3307和DTA-6显著提高了籽粒中蔗糖含量,S3307同时提高了2个品种籽粒果糖含量,而DTA-6降低了合丰50籽粒果糖含量;S3307和DTA-6提高了合丰50籽粒淀粉含量,降低了垦丰16籽粒淀粉含量,说明调节剂对不同的大豆品种调控效果存在差异。调节剂增加叶片蔗糖含量的同时,S3307和DTA-6提高了叶片SPS和SS活性;在多数测定时期内,显著降低了叶片转化酶活性。S3307和DTA-6协调了源库系统碳水化合物代谢的动态平衡。与清水对照(H-CK和K-CK)相比,调节剂处理H-S、H-D和K-S、K-D两年平均增产为20.07%、14.57%?
[Objective] The aim of this paper was to investigate the effect of plant growth regulators on carbohydrate content,sucrose metabolizing enzyme activities and yield of soybean in the source-sink theory aiming to provide scientific basis for PGRs on agricultural production. [ Method ] Foliar spray field experiments were conducted successively in 2013 and 2014 in the main soybean producing zone, Heilongjiang Bayi Agricultural University. The experiment was in the early flowering by foliar spray one time. Taking Hefeng50 and Kefengl6 soybean varieties as the main research materials. Two chemical regulators, 2-N,N-diethylamino ethylcaproate (DTA-6, 60 mg·L^-1) and uniconazole (S3307, 50 mg·L^-1) were tested with water as the control. The first sampling was carried out after sprayed 30 d, and then leaf samples were collected once every five days. The contents of sucrose, starch or fructose in leaves and seeds, and invertase activity, SPS or SS activity in leaves were measured. The grain yield of soybean were investigated. [Result] At the early seed filling stage (30-35 days since spraying of DTA-6 and S3307), the sucrose, fructose and starch contents of leaves showed the downtrends, and that of seeds showed increasing trends, which showed that more carbohydrates were applied to seeds growth and development. At the middle seed filling stage (35-45 days since spraying of DTA-6 and S3307) , the sucrose, fructose and starch contents of leaves always showed increasing trends by S3307 .The sucrose and fructose contents were all higher than the control, which was based to provide sufficient materials for the grain filling. At the late seed filling stage (after the 50th day since the spraying by DTA-6 and S3307) , the sucrose contents of leaves reached the maximum by DTA-6 and S3307, and reached significant levels to CK. The starch content of leaves sprayed with S3307 were higher than CK, and the fructose contents of leaves sprayed with DTA-6 were higher than CK. The sucrose contents of seeds were signif