聚乙二醇(PEG6000)模拟干旱胁迫抑制矮沙冬青种子的萌发

Abstract

In this paper, we have taken the seeds of endangered species Ammmopiptanthus nanus (M. Pop.) Cheng f. as the test material, and studied on the effects of simulated drought stress with different concentration and osmotic potential of polyethylene glycol (PEG6000) on their seminal germination, such as germination capacity, average speed of germination, length of radicle and hypocotyls, germination index and viability index. The results showed that PEG could retard the proceeding of seeds germination of Ammmopiptanthus nanus (M. Pop.) Cheng f. and the germination percentage, germination index, and seed viability index were all showed the downtrend obviously with increasing concentration of PEG. The seeds treated with -1.20 MPa water potential of PEG could not germinate at all after the experiment finished, so we suggested that -1.20 MPa water potential was the threshold for the germination of Ammmopiptanthus nanus (M. Pop.) Cheng f. seeds. Under the treat condiction of -0.20 MPa water potential of PEG, test material even have a same germination percentage comparing with contrast (CK), the lengths of radicle and hypocotyl were shorter, it illustrated that the growth of radicle and hypocotyl may be more sensitive to PEG-simulated drought stress than germination percentage. Then drought stress might be a possible cause that inhibited the natu-ral regeneration of Ammmopiptanthus nanus (M. Pop.) Cheng f. . This paper should be provide a scientific foundation for the protection of species resources and the populations recovery of Ammmopiptanthus nanus (M. Pop.) Cheng f. .