【摘要】 聚乙二醇(PEG-6000)渗调处理提高花生种子活力,促进萌发,增强抗寒能力。在15℃下,用20～25%(-0.6～-0.8mpa)PEG溶液对花生种子渗调2天,获得最大效应。实验室和田间试验(春季)均表明,PEG渗调处理种子的发芽率和活力指数均比对照种子高。低温吸胀时,经渗调的种子内含物外渗量及速率均较对照种子低,膜脂脂肪酸不饱和指数提高,亚麻酸(18∶3)相对含量增加。亚麻酸/棕榈酸比值与种子活力成正比(r=0.85)。更多还原

【Abstract】 The germination rate and uniformity of peanut seeds were significantly im-proved by osmoconditioning with polyethylene glycol（PEG）,especially in the medium-and low-vigor seeds.Priming with solution of 20 and 25%（or-0.6 and -0.86Mpa）PEG at 15℃ for 2 days provided the maximum promotive effect on rate and the uniformity of peanut seedling emergence in both laboratory and cold soil fieldeondition.The time for 50% emergence of high-and low-vigor peanut seeds were reduced from 37 to 22 days and from 40 to 28 days respectively;the emergence was increased respectively from 67.65% and 52.5% to 90% and 85.56%.In addition,the vigor index and weight,length of stem and root were increased. When the seeds were soaked in low temperature（3～4℃）,the leakage ofplasma membrane was decreased by osmoconditioning.The speed of leakage of untreated seeds(1.2cm.h^-1.)was greater than that of the treated seeds(0.54cm.h^-1.) The degree of unsaturation of fatty acid in membrane lipids under low tem-perature was changed.The index of unsaturation of fatty acid（IUFA）of mem-brane lipids in control seeds was reduoed from 146.7 to 133.7 after preteatment of seeds with low temperature（10～12℃）for 15 days,but that in priming seeds was just a little bit changed（from 146.7 to 145.7）.The IUFA of membrane lipids in untreated seeds was reduced faster than that in treated seeds with pro-longation of the low temperature（3～4℃）treatment.The difference of IUFA between treated and untreated seeds due to the change of linolenic acid（18∶3） content.The ratio of 18∶3/16∶0（16∶0 palmitic acid）in priming seeds was in-creased to 141.6% of that in untreaed seeds.The change of vigor and cold hardi-ness in seeds were related to the degree of unsaturation of fatty acid in membrane lipids and permeability of plasma membrane.更多还原