Drought limits pollen tube growth rate by altering carbohydrate metabolism in cotton (Gossypium hirsutum) pistils

摘要: Abstract It has been reported that drought stress (DS) reduces cotton yield by negatively affecting reproductive activities. Some studies have investigated the effects of DS on pollen physiology and biochemistry, but exploring impact pistil biochemistry its relationship with tube growth rates in vivo are scarce. In order to investigate these objectives, a greenhouse study was conducted sensitive cultivar, Yuzaomian 9110. Two water treatments were imposed at flowering stage, 1. control, where plants irrigated optimum quantity 2. treatment, 50% water. Results indicated stored starch content early stage (12:00 h) 31.6% lower drought-stressed pistils than control pistils, it highly correlated rate. The decline accumulation could be attributed impeded transport photosynthetic carbon assimilates. Moreover, decreased ADP-glucose pyrophosphorylase soluble synthase activities also resulted curtailing pistils. Furthermore, sucrose concentration significantly higher droughted relative 12:00 18:00 h (during rapid period), which due acid invertase, down-regulated expressions genes, GhSusA, GhSusB GhSusD, invertase GhINV1 GhINV2, limiting as result hydrolysis into hexose. Drought-stressed sampled had α-amylase activity compared resulting decomposition, which, conjunction sucrose, led glucose fructose contents 18:00 h. Finally, pyruvate level not produce enough acetyl-CoA tricarboxylic cycle sufficient energy (ATP) for growth. We conclude disrupts carbohydrate balance pistil, reducing consequence supply elongation style, will ultimately failure.