不同成熟度花生胚萌发时子叶中贮藏蛋白质的降解

花生(Arachis hypogaea L.)汕油71果针入土20d(20 DAP)的种子剥去种皮后,10％的胚可以萌发,至40 DAP发芽率达98％。不同发育时期的花生胚萌发 10d后子叶盐溶蛋白质和花生球蛋白降解表明,20和32 DAP胚萌发后,子叶中这些蛋白质只有部分降解。随着胚成熟度增加,子叶中降解这些蛋白质的能力不断提高。20～40 DAP胚萌发4d时,子叶的BAPAase和GHE活性较低。50～80DAP胚萌发 4d,子叶中上述两种酶均显示较高的活性。

Degradation of Storage Protein in the Cotyledons of Maturating Peanut Embryos During Precocious Germination

After the removal of the seedcoat, the immature embryos of Arachishypogaea L. cv. Shanyou 71 (peanut)germinated and reached 98 % of germi-nation at 40 d after pegging (DAP).Benzoylarginine-p-nitroanilidase (BA-PAase) activity in the cotyledons of 60DAP embryos increased and had twoactivity peaks after precocious germi-nation. Gelatin--hydrolytic enzyme(GHE) activity in the cotyledons ap-peared at 1 d after precocious germina-tion. The salt--soluble proteins andarachin in the cotyledons began to de-grade rapidly after 2 d of germination,and the content of these proteins de-clined to a very low level 10 d afterprecocious germination. Only part ofthese proteins in the cotyledons of 20and 32 DAP embryos degraded duringprecocious germination. As the embryomaturity advanced, the degradationcapacity of storage proteins in cotyle-dons of embryos after precocious ger-mination increased. There were no dif-ferances in BAPAase activities in thecotyledons of 20 to 40 DAP embryoswhether they were germinating or not.No GHE activities were observed in theungerminated embryos at different de-velopmental stages and in the germi-nated 20 DAP embryos. GHE activi-ties in embryos after precocious germi-nation increased as the age of the em-bryo advanced from 32 to 80 DAP.