Effects of S-ABA on Growth and Physiological Characteristics of Rice Seedlings Under Low Temperature Stress
In order to understand the regulation effect of S-ABA on the growth and physiological characteristics of rice seedlings under low temperature stress,and to explore the physiological response mechanism and recovery effect of rice seedlings under low temperature stress and S-ABA application,Chaoyou 1000 was used as the material,and after 3.1 leaf age,it was treated at low temperatures of 5 ℃(T0),9℃(Tl),13 ℃(T2)for five consecutive days in an artificial climate chamber(low temperature treating from 18:00 to 08:30 next day)and the normal temperature growth was restored after the low temperature stress,and seven days before low temperature treatment,topdressing 0.03%S-ABA(diluted 100 times)to set the treatments of T0S,T1S and T2S to study the effects of S-ABA on the growth and physiological characteristics of rice seedlings under low temperature stress.The results showed that under low temperature stress,foliar application of S-ABA effectively improved rice growth,increased plant height,root length,stem base width,leaf area and dry matter weight of rice seedlings,increased photosynthetic pigment content of rice leaves,and enhanced the photosynthetic capacity and antioxidant enzyme activity of rice leaves.At the same time,it also increased the content of endogenous hormones IAA,GA and SA and reduced the content of endogenous hormone ABA,helping maintain the homeostasis of endogenous hormones and normal metabolism in rice and improve the cold tolerance of rice.The effect of S-ABA on the third day after the beginning of low temperature stress was the most obvious,indicating that S-ABA would have the best effect when it is used to regulate the growth of rice seedlings in the early stage of low temperature stress to deal with chilling injury.
riceS-ABAlow temperature stressseedling growthphysiological characteristic