排序方式： 共有4条查询结果，搜索用时 15 毫秒
1
1.
《Scandinavian Journal of Forest Research》2012,27(6):520-531
Abstract Masson pine (Pinus massoniana Lamb.), a native species widely distributed in temperate forests in central China, and Loblolly pine (Pinus taeda L.), an exotic tree species introduced to China from southeastern United States, are dominant evergreen conifers that play a pivotal role in maintaining forest structure and functions for the region. We examined the effects of freezing on these species with chlorophyll fluorescence and electrolyte leakage using both field- and laboratory-based experiments in September 2009 and January 2010, respectively. We found that freezing could cause a greater impact on the Loblolly pine than the Masson pine. Although the two species showed similar values of F v /F m and electrolyte leakage before freezing, the Masson pine needles showed lower F v /F m and higher electrolyte leakage ratios than those of the Loblolly pine when treated in low temperatures (?15 to 0°C). We also found that cold-acclimation was crucial for both species to adapt to low temperatures with the F v /F m ratio decreased approximately by 80% in the first freezing hour for the non-acclimated needles of both species while the cold-acclimated needles showed little changes in the F v /F m ratio. This finding is also supported by our measurements of electrolyte leakage. These results suggest that the Loblolly pine could be more susceptible to freezing damages than the Masson pine in central China. 相似文献
2.
日本桃叶珊瑚(Acuba jap variegate)在低温下的光合作用及蛋白的研究初报 总被引：1，自引：0，他引：1
本论文旨在通过人工模拟低温环境，测定常绿植物桃叶珊瑚在低渐下的光合作用，探索其在北京越冬的抗寒机制，并通过双向电泳分离与抗寒性有关的特异蛋白，实验发现，桃叶珊瑚在10℃长期处理后，光合作用是25℃时的40％左右，经4℃长期处理不能进行光合作用，双向电泳分析发现有一种小分子量蛋白，在常温下存在，低温下不存在，推测此蛋白可能是与抗寒性有关的基因表达的抑制因子。 相似文献
3.
Antonio Michele Stanca Cristina Crosatti Maria Grossi Nadia Gloria Lacerenza Fulvia Rizza Luigi Cattivelli 《Euphytica》1996,92(1-2):215-219
Summary Molecular adaptation to cold and drought involves a series of biochemical and molecular changes leading plants to improve their winter hardiness or drought resistance.We are interested to study the molecular basis of cold acclimation and drought response of barley to survive under stress. Several genes regulated by low temperatures and sometimes by drought have been isolated from the barley genome. In this review the most significant results of our recent work will be presented and discussed.The protein encoded by cDNA clone pt59 and induced in barley by cold was over-expressed in E. coli to produce the matching antibody, which in vivo recognizes a cold-induced protein of 14 kDa (COR14). The COR14 is stored in amounts only slightly greater in the cold resistant Onice than in the susceptible Gitane, although the former has a higher induction-temperature threshold of COR14 than the latter. This fact is an evolutionary advantage enabling the resistant varieties in the field to prepare for the cold well ahead of the susceptible ones.Two other cDNA clones, paf93 and cdr29, are regulated by low temperature and drought stress but not by exogenous ABA treatment. Indeed during the early stage of dehydration, the mRNAs are expressed before the induction of known ABA regulated genes such as dehydrins and when only a small increase occurs in ABA content. The sequence analysis revealed that paf93 encodes for a protein homologous to the cold-regulated protein COR47 of Arabidopsis, whereas cdr29 represents a plant gene homologous to yeast and mammalian sequences coding for acyl-Coenzyme A oxidase.Abbreviations ABA
abscisic acid
- COR
cold regulated 相似文献
4.
1