Action of growth regulators on osmotic potential of soybean (Glycine max cv. Davis)

aesalq Anais da Escola Superior de Agricultura Luiz de Queiroz An. Esc. Super. Agric. Luiz de Queiroz 0071-1276 2316-8935 Universidade de São Paulo; Escola Superior de Agricultura Piracicaba, SP, Brazil This research deals with the effects of exogenous growth regulators on leaf osmotic potential of 'Davis' soybean. To study the influence of growth substances on osmotic potential (2-chloroethyl) trimethylammonium chloride (CCC) at concentration of 2,000 ppm, succinic acid-2,2-dimethylhydra-zide (SADH) 4,000 ppm, gibberellic acid (GA) 100 ppm, and indolylacetic acid acid (IAA) 100 ppm were applied. The leaf osmotic potential established every day during three days showed that plants treated with SADH presented lower (negative) osmotic potential. Ação de fitoreguladores no potencial osmótico da soja (Glycine max cv. Davis) Action of growth regulators on osmotic potential of soybean (Glycine max cv. Davis) Paulo R.C. Castro Departamento de Botânica, E.S.A. "Luiz de Queiroz", USP RESUMO Determinou-se em condições de casa de vegetação o efeito de fitoreguladores no potencial osmótico foliar da soja. As aplicações das substâncias de crescimento foram realizadas 21 dias após a semeadura. Efetuou-se pulverização de cloreto (2 -cloroetil) trimetilamônio (CCC) 2.000 ppm, ácido succínico-2,2-dimetilhidrazida (SADH) 4.000 ppm, ácido giberélico (GA) 100 ppm, ácido indolilacético (IAA) 100 ppm, além do controle. O potencial osmótico foliar foi determinado durante três dias em intervalos de 24 horas. Utilizou-se o delineamento inteiramente casualizado com 4 repetições e procedeu-se à comparação de médias pelo teste Tukey (57o). Os resultados obtidos pelo método osmométrico mostraram que plantas tratadas com fitoreguladores apresentam variação no potencial osmótico foliar dependendo da disponibilidade hídrica do substrato. Aplicação de SADH reduziu o potencial osmótico da soja 'Davis'. SUMMARY This research deals with the effects of exogenous growth regulators on leaf osmotic potential of 'Davis' soybean. To study the influence of growth substances on osmotic potential (2-chloroethyl) trimethylammonium chloride (CCC) at concentration of 2,000 ppm, succinic acid-2,2-dimethylhydra-zide (SADH) 4,000 ppm, gibberellic acid (GA) 100 ppm, and indolylacetic acid acid (IAA) 100 ppm were applied. The leaf osmotic potential established every day during three days showed that plants treated with SADH presented lower (negative) osmotic potential. Texto completo disponível apenas em PDF. Full text available only in PDF format. LITERATURA CITADA Entregue para publicação em 23/12/1980. BOYER, J.S., 1980. Differing sensitivity of photosynthesis to low leaf water potentials in corn and soybeans. Plant Physiol. 46: 236-239. Differing sensitivity of photosynthesis to low leaf water potentials in corn and soybeans Plant Physiol. 236 239 46 BOYER J.S. BOYER, J.S., 1971. 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