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31.
Abstrct
Thuja orientalis seeds was treated by different molecular weight, different concentration and different lasting time in the Seedling Laboratory
of Northeast Forestry University. The results are as follows:(1) it shows significant promoting effects on the germination
viability of seeds by different molecular weight of PEG(-6000, -10000 and -20000), and PEG-10000 is the best. (2)Different
effects on germination viability, germination rate and simple vigor index are made by different concentration of the same
weight molecular(PEG-10000), the promoting effects are shown when the concentration is below 30%, and from 20% to 30% is the
best range, but inhibitions will be shown if the concentration is more than 35%. (3)The most suitable lasting time of osmose
treatment of PEG-10000 with 20% concentration is from 2 to 4 days, not more than 6 days, but it will show significant inhibition
if the treated time is more than 8 days. (4)The treatments of PEG-10000 and PEG-20000 with higher molecular weight can increase
the germination rate and seed vigor, and decrease the electric conductivity of the seed soaking liquid after the natural air-dry
treatment. The suitable time of natural air-dry is about 6 to 8 hours. It is also concluded that the PEG osmose treatment
is an effective method to increase the germination rate by the field simulation in the laboratroy. 相似文献
32.
Yang Yong-qing Wang Xiao-feng 《中国林学(英文版)》2005,7(2):7-11
The soybean (Glycine max) Heihe No. 23 is sensitive to imbibitional chilling injury. Polyethylene glycol (PEG) treatment can improve chilling tolerance of soybean seeds to a certain extent. The changes of hydrolytic ATPase in plasma membranes and H^+-pumping responses in soybean seeds were investigated during PEG treatments. Effects of exogenous calcium and exogenous ABA on the hydrolytic ATPase were also examined in order to understand the mechanism of chilling resistance. Highly purified plasma membranes were isolated by 6.0% aqueous two-phase partitioning from soybean seeds, as judged by the sensitivity of hydrolytic ATPase to sodium vanadate. PEG treatment resulted in a slight increase of the hydrolytic ATPase activity in 12 h. Then the activity decreased gradually, but still higher than the control. The H^+-pumping activity increased steadily during PEG treatment. Exogenous calcium had both activating and inhibiting effects on the hydrolytic ATPase, but the activity was inhibited in soybean seeds treated with exogenous ABA. Results suggested that PEG treatment, not the exogenous calcium and ABA, up-regulated H^+-ATPase activities in soybean seeds. 相似文献
33.
卵黄抗体(Ig Y)具有许多其他类型抗体所没有的优点,其分离纯化的方法有有机物抽提法、盐析法、水稀释法等。试验分别用聚乙二醇(PEG)6000和氯仿来提取卵黄抗体,对其收集的抗体量和抗体效价进行比较分析。结果表明:100 g的卵黄用PEG6000法比氯仿法多收集71 m L卵黄抗体溶液,且PEG6000法的成本远远低于氯仿法,有很好的经济效益,而PEG6000法提取的卵黄抗体效价比氯仿法略低一个滴度。 相似文献
34.
通过选用渗透调节剂聚乙二醇(PEG)处理柠条种子,并对柠条种子的发芽情况进行试验研究,结果表明:在水分胁迫条件下,柠条种子萌发存在一定的差异;一定浓度范围内,随着PEG溶液浓度的增强,柠条种子的发芽率提高,发芽速度加快。据文献报道,当PEG处理的强度达到一定水平时,会对种子的萌发产生抑制作用,但本试验还没有得到对柠条种子产生抑制作用的PEG浓度。 相似文献
35.
以玉米杂交种创奇518新种子为材料,以不同浓度配比的聚乙二醇(PEG)、二甲基亚砜和水杨酸组合作为引发剂,采用L9(34)正交试验设计,通过低温种植处理,研究提高玉米种子抗寒性的3种引发剂的最佳浓度配比。结果表明,不同配比引发处理的玉米种子发芽势、发芽率、苗鲜重、活力指数、过氧化物酶(POD)和过氧化氢酶(CAT)活性均表现出明显差异。以浓度为20%的PEG、浓度为0.5%的二甲基亚砜和浓度为0.007%的水杨酸组合处理种子的发芽率、活力指数最高,幼苗长势整齐一致,POD和CAT较对照有明显提高。 相似文献
36.
37.
[目的]探讨紫薇种子的抗旱性。[方法]以紫薇为试验材料,采用不同质量分数(0、5%、6%、7%和9%)的聚乙二醇(PEG6000)模拟干旱胁迫,探讨其对紫薇种子萌发的影响。[结果]紫薇种子的发芽率、发芽指数、活力指数等指标随着PEG浓度升高(5%~7%)呈下降趋势,但差异不显著;幼苗的上胚轴呈下降趋势,而侧根数和下胚轴呈上升趋势;当PEG浓度达到9%时,各项指标均显著下降。[结论]在实验室条件下,紫薇种子能忍受PEG(5%~7%)的渗透胁迫,紫薇幼苗通过减少地上部分生长、增加地下部分生长的方式来适应适度干旱胁迫。 相似文献
38.
《Plant Production Science》2013,16(3):359-364
AbstractA priming method called sand priming was developed using sand as a priming solid matrix. The effect of sand priming on improving the field emergence performance of five super sweet corn cultivars was investigated. Sand priming significantly improved field emergence performance of all super sweet corn cultivars, and there was marked improvement by priming at 20ºC for 24 hr. After sand priming at 20ºC for 24 hr, field emergence percentage (FEP) of “Green Superman”, “Huatian 1”, “Yangtian 1”, “Mitian 8”, and “Chaotian 43” was increased by 52.1%, 37.5%, 38.0%, 40.9%, and 33.3%, respectively. Their field emergence speed (FES) was 2.3, 1.8, 2.0, 2.0, and 1.8 times of the control, respectively. To further elucidate the effect of sand priming on improving the field emergence performance of super sweet corn, we analyzed the membrane system integrity, α-amylase activity and protein content. Sand priming at 20ºC for 24 hr improved membrane system integrity and α-amylase activity in all super sweet corn cultivars. Furthermore, sand priming at 20ºC for 24 hr accelerated the degradation of embryo protein after 1 d germination in “Green Superman”. 相似文献
39.
40.
以野生和栽培蒲公英为材料,采用PEG(聚乙二醇)溶液模拟土壤干旱的方法,研究了不同浓度PEG溶液对蒲公英叶片含水量、叶绿素含量、质膜透性、保护酶活性以及渗透调节物质的影响。结果表明:野生和栽培蒲公英在抗旱适应性上存在显著差异。随着PEG浓度的增加,野生蒲公英叶片含水量、叶绿素和可溶性蛋白含量的下降幅度,质膜透性、抗氧化酶活性、游离脯氨酸以及可溶性糖含量的上升程度均小于栽培蒲公英,对干旱环境的适应性强于栽培品种,具有较强的抗旱能力。 相似文献