Soybeans growth regulation

Triazolylcyclopropane derivatives are endowed with antimycotic properties [125]. They are also prepared as plant growth regulators and fungicides for instance 93 (R = unsubstituted and substituted aryl, heteroaryl) markedly inhibited the growth of rice, cotton and soybeans in hot tests [126]. l-(l,2,4-Triazolyl)-2-(2,4-dichlorophenyl)cyclopropane 94, is a more effective fungicide against Podosphaera leucotricha and a better growth retardant in rice and soybeans than the (l,2,4-triazolyl)pentenone 95, Eq. (36) [127]. 

Figure 19. Plant growth regulating activity of triapenthenol (RSW 0411) and its (+)-R (KTU 1591 inactive) and (-)-S-enan-tiomer (KTU 1592 active) soybeans.

Growth regulators can influence a plant s absorption of minerals from the soil. The uptake of potassium by wheat, for example, is accelerated by treating the plant with gibberellic acid. The uptake of both nitrogen and phosphorus by wheat and soybean plants is enhanced by treatment with 2,4-D. 

In the 1960 s, 2,3,5-triiodobenzoic acid was considered a spectacular plant growth regulator. When applied to the leaves of soybeans, it shortens the plants, increases their branching, stiffens them, and increases pod set (thus increasing yield). Unfortunately, the compound is not always effective. Scientists have found that the timing of its application is very critical and that different varieties respond differently. Hence, results are disappointingly inconsistent, and the use of this compound to increase soybean yields has been discontinued. 

Unsubstituted and substituted aryl- and heteroarylcyclopropyl (methyl-1,2,4-triazolyl)-carbinols have been prepared and used as fungicides and plant growth regulators. Thus the cyclopropylcarbinol 97 (R1 =p-ClC6H4> R2= SEt) inhibited the growth of rice, cotton and soybean, and protected apple against Ven-... 

Concerning our evaluation program the titled thiolearbamates and carbamates exhibited activity as plant growth regulators for soybean and corn. The most active compounds possessed the general formula NCR NC(=0)SR, where R =ethyl or propyl and R=methyl (compounds 12 and 13). However, additional synthesis and testing are needed in order to determine the true merits of the titled compounds for this application. 

In most cases, a detectable induction of mRNA levels is observed within 15-30 min following auxin exposure. The levels of three soybean mRNAs (detected by the cDNA clones 6, lOA and 15) are induced by 2.5 min of treatment of excised elongating soybean hypocotyl sections with the synthetic auxin 2,4-D [8]. These mRNAs and others identified in soybean [5, 16], pea [13] and tobacco [14] are specifically induced by auxins such as lAA and NAA, and not induced by nonauxin analogs. With some exceptions, these auxin-induced sequences do not accumulate in response to other plant growth regulators such as GA, ABA, cytokinins and ethylene, or to environmental stresses such as heat shock or cold... 

Prospects for Economic Benefit. As of May 1992, EPA registrations of biorationals included 14 pheromones, 6 plant growth regulators, 13 floral lures, 5 natural insect growth regulators, and 4 others (including diallyl sulfoxide, carboxymethyl cellulose, soybean oil as a miticide). 

Radhakrishnan R, Lee IJ (2013b) Spermine promotes acclimation to osmotic stress by modifying antioxidant, abscisic acid, and jasmonic acid signals in soybean. J Plant Growth Regul 32 22-30... 

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