Effect of growth regulators on reproduction in soybeans

Flower abscission in soybean as affected by assimilate supply and hormone levels

“…Effects on the vegetative soybean plant such as shortening of intemodes, loss of apical dominance, epinasty of young leaves, and premature abscission of apical leaves confirmed this hypothesis. The same pod set increase shown with the application of TIBA was accomplished by the removal of the apex, (Greer, 1964, Greer andAnderson, 1965) or both the apex and all reproductive structures at one time, namely two weeks after anthesis (Amuti, 1983). Greer (1964) applied TIBA at the start of flowering to increase pod set, whereas Nooden and Nooden (1985) found that application before anthesis increased the pods formed per node but not the total number per plant.…”

“…The effect of TIB A on the dry weight distribution in the plant was not studied here. Greer (1964) showed that TIBA sprayed onto field grown soybean plants resulted in greater total dry weight, with less accumulation in the leaves and more in the stem+petiole and pod+seed fractions, throughout the whole growing season. The increased partitioning of dry weight to the reproductive organs agrees with the results found with BAP in these experiments.…”

“…The anti-auxin, TIBA, also has been found to increase the number of pods produced on the plant (Greer, 1964;Greer and Anderson, 1965;Basnet et al, 1972;Nooden and Nooden, 1985). This increased pod number per plant resulted from increased branching and pod formation on these branches (Basnet et al, 1972) or increased pod set (Greer, 1964;Nooden and Nooden, 1986). TIBA also has been found to increase flower production (Galston, 1947;Greer, 1964) and to hasten flowering and maturation (Greer, 1964;Greer and Anderson, 1965).…”

“…This increased pod number per plant resulted from increased branching and pod formation on these branches (Basnet et al, 1972) or increased pod set (Greer, 1964;Nooden and Nooden, 1986). TIBA also has been found to increase flower production (Galston, 1947;Greer, 1964) and to hasten flowering and maturation (Greer, 1964;Greer and Anderson, 1965). Galston characterized the effect of TIBA as an anti-auxin type of compound by its effect in Avena curvature tests.…”