Lactofen and kinetin in soybean yield

ABSTRACT The herbicide lactofen has been used by producers in many conditions, in order to increase the soybean yield. This study aimed to evaluate the influence of lactofen and the phytohormone kinetin on the morpho-agronomic traits, carbohydrate partitioning and yield, in soybean cultivars. Three experiments were carried out in the field, in addition to one experiment in a greenhouse. A randomized block design, with four replications, was used. The treatments were: lactofen [144 g ha-1 of active ingredient (a.i.)], lactofen + kinetin (144 g ha-1 of a.i. + 0.5 g ha-1), kinetin (0.5 g ha-1), manual cutting of apical buds and control. In the subplots, six soybean cultivars (M 6410 IPRO, M 5917 IPRO, NS 7670 RR, NS 6909 IPRO, BMX Lança IPRO and Produza IPRO) were used. In the field, the plant lodging index, plant height, number of nodes and branches, pods and grains per plant, mass of 100 grains and grain yield were evaluated. In the greenhouse, the starch, reducing sugars, sucrose and total sugars in the leaves, stems and roots of three soybean cultivars were quantified. The application of lactofen in the V6 stage influenced the morpho-agronomic traits of the cultivars in the field and increased the soybean yield by 312 kg ha-1, considering all the cultivars. The phytohormone did not influence the morpho-agronomic traits neither the grain yield. The treatments did not induce modification in the partitioning of carbohydrates destined to the roots.

摘要：除草剂乳氟禾草灵（lactofen）已被众多种植者在多种种植场景下应用，以期提升大豆产量。本研究旨在评估乳氟禾草灵与植物激素激动素（kinetin）对不同大豆品种的形态农艺性状、碳水化合物分配及产量的影响。本研究共开展3项田间试验及1项温室盆栽试验，均采用随机区组设计并设置4次重复。试验处理设置如下：①乳氟禾草灵（有效成分用量144 g·ha⁻¹）；②乳氟禾草灵+激动素（有效成分用量分别为144 g·ha⁻¹与0.5 g·ha⁻¹）；③激动素（用量0.5 g·ha⁻¹）；④人工打顶；⑤空白对照组。副区试验选用6个大豆品种，分别为M 6410 IPRO、M 5917 IPRO、NS 7670 RR、NS 6909 IPRO、BMX Lança IPRO及Produza IPRO。田间试验测定指标包括植株倒伏指数、株高、节数与分枝数、单株荚数与粒数、百粒重及籽粒产量。温室试验则对3个大豆品种的叶片、茎秆及根系中的淀粉、还原糖、蔗糖及总糖含量进行定量分析。于V6生育期喷施乳氟禾草灵可显著影响供试大豆品种的田间形态农艺性状，且在所有供试品种中可使大豆产量提升312 kg·ha⁻¹。单独施用激动素既未对供试品种的形态农艺性状产生影响，也未显著影响籽粒产量。各试验处理均未显著影响碳水化合物向根系的分配过程。