论文部分内容阅读
以弯刺蔷薇(Rosa beggeriana)和大花白木香(R.fortuneana)当年生叶片和枝条为试材,采用电解质渗出率拟合Logistic方程确定低温半致死温度(LT_(50))评价抗寒性,采用过碘酸雪夫氏染色观察茎中淀粉积累,测定相对含水量、丙二醛、可溶性糖、脯氨酸、脱落酸含量以及超氧化物歧化酶、过氧化物酶和过氧化氢酶活性,研究其越冬期间抗寒性变化及其生理基础。结果发现:两种蔷薇叶片抗寒能力相当,但弯刺蔷薇枝条抗寒性远强于大花白木香。与大花白木香相比,弯刺蔷薇在低温驯化初期累积了更多的可溶性糖,并在叶片脱落前可能通过增加的ABA信号促进可溶性糖由叶片向茎中运输并贮存为淀粉,在严冬时期淀粉水解形成更多的渗透调节物质,并通过更高的SOD活性维持氧化还原平衡;而大花白木香中只发现了比弯刺蔷薇中更高的脯氨酸含量和POD活性,这可能难以维持其渗透压和氧化还原平衡并造成了更多的膜脂过氧化伤害,最终导致其枝条的抗寒性远小于弯刺蔷薇。
The leaves and shoots of Rosa beggeriana and R. fortuneana were used as materials to determine the resistance to cold by semi-lethal temperature (LT_ (50)) according to the electrolyte exudation fitting Logistic equation The starch accumulation in the stems was observed by the periodic acid Schiff’s staining. The relative water content, malondialdehyde, soluble sugar, proline and abscisic acid content, superoxide dismutase, peroxidase and catalase Activity, to study its cold resistance during winter and its physiological basis. The results showed that both of the two rose leaves had the same ability of cold resistance, but the cold resistance of the rose rose branch was stronger than that of the big flower white wood. Compared with the large white woody, Rosebrush accumulated more soluble sugars in the early stage of cold acclimation and may promote the transport of soluble sugar from the leaves to the stems by the increased ABA signal and store it as starch before the leaves fall off. In winter Starch hydrolyzed to form more osmoregulation substances and maintain the redox balance through the higher SOD activity. However, only the higher proline content and POD activity were found in the flowers, It is difficult to maintain its osmotic pressure and redox balance and cause more membrane lipid peroxidation damage, eventually leading to the cold resistance of its branches is much smaller than the Rose Bristles.