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71.
外源DNA导入小麦变异后代主要性状遗传力和相关性研究   总被引:4,自引:0,他引:4  
用花粉管通道法将几种植物总DNA片段导入小麦,对变异后代5个农艺性状的遗传力、遗传变异系数及性状间的相关系数进行了估算。结果表明:株高的遗传力最大,其次为千粒重和穗长。每穗粒数和每株穗数的遗传力最小。遗传变异系数以每株穗数和千粒重最高。在相关系数方面,株高与千粒重、株高与每株穗数、穗长同每穗粒数都有极显著的遗传型正相关;株高与每穗粒数、穗长与每株穗数、每株穗数与生产粒数、每株穗数与千粒重4对性状间  相似文献   
72.
以良种油茶种子和嫁接苗为试验材料,设计3种外源激素处理方式,探讨外源激素对油茶种子萌发、根系生长及油茶轻基质嫁接容器苗生长的影响。结果表明:适宜的激素处理对油茶种的根系生长、出芽和轻基质嫁接容器苗的生长具有促进作用。用50mg/L ABT处理过的油茶种子根系生长迅速、主根饱满健壮、须根浓密,发根质量好,Ⅱ级根出现早,须根出现和出芽时间比对照均提前7d左右。在轻基质嫁接容器苗株高生长和地径生长上具有显著的生长优势,可以在生产中推广使用。  相似文献   
73.
为了缓解玉米生产中涝渍胁迫带来的问题,通过小区试验,研究外源多胺拌种对玉米抗涝能力的影响。结果表明,淹水后,多胺拌种植株的丙二醛物质的量浓度均低于不拌种植株,且在恢复期内基本能下降到正常水平;多胺拌种植株的可溶性蛋白和可溶性糖质量分数在处理时期均低于不拌种植株,淹水后均升高,且表现出先升后降的趋势;淹水条件下,百粒质量和产量均大幅度下降,在淹水3、5、7、9d条件下,多胺拌种和不拌种植株百粒质量下降幅度分别为2.94%、14.42%、21.88%、22.11%和16.24%、18.30%、25.59%、27.99%,产量降幅分别为32.10%、43.20%、48.74%、43.94%和35.13%、47.65%、53.67%、48.86%;持续淹水条件下,多胺拌种产量比不拌种产量最高可提高625.11kg/hm2。  相似文献   
74.
两种野生花灌木硬枝扦插繁殖试验   总被引:5,自引:0,他引:5  
以燕山东段两种野生花灌木蚂蚱腿子(Myripnoisdioica)和胡枝子(Lespedezabicolor)为材料,进行了硬枝扦插研究。结果表明:(1)两种花灌木均为皮部生根类型,蚂蚱腿子不形成愈伤组织,胡枝子仅有少量插穗产生极微量的愈伤组织;(2)两种花灌木的最适外源激素和浓度并不相同,其中100mg·kg-1的NAA对蚂蚱腿子的生根率影响最显著;100mg·kg-1的IBA可有效提高胡枝子的生根率、根长及不定根根数。  相似文献   
75.
The effect of the application of acidified porous hydrate calcium silicate (APS) in nursery bed soil and porous hydrate calcium silicate (PS) in paddy fields on the growth of rice plants ( Oryza sativa L. cv. Hitomebore) was examined in 2002 and 2003. The results revealed the following: 1) Shoot dry weight of rice seedlings increased by APS treatment in nursery bed soil. The tiller number of rice plants after transplanting in both years also increased by APS treatment in nursery bed soil, and in 2003, the tiller number in the treatment with a combination of APS in nursery bed soil and PS in paddy fields was significantly higher than that in the other treatments until the maximum tiller number stage. Furthermore, the root length of rice plants 14 d after transplanting increased by APS treatment in nursery bed soil. 2) Silicon concentration in the soil solution significantly increased by PS treatment in paddy fields, and the concentration of dissolved carbon oxide increased by APS treatment in nursery bed soil. 3) Only in the APS treatment the rice yield was 341 g m−2, while 400 and 450 g m−2 in the PS and both APS and PS treatments, respectively, in 2003. Percentages of ripened grains in the plots without PS treatment ranged from 57 to 63%, respectively, while, those in the PS treated plots were 82%. The numbers of panicles and ripened grains in both APS and PS treatments were the highest among the treatments. Based on the above results, we concluded that both APS in nursery bed soil and PS in paddy field treatments were effective in improving the silicon nutrition and growth of rice plants, and that this effect was enhanced by a combination of treatments with the two.  相似文献   
76.
调查了100份水稻资源6个性状对外源GA3的敏感性,并分别以株高、穗颈长和剑叶角度的GA3敏感性指标为变量对100份资源进行了聚类分析。结果表明:与喷清水对照相比,GA3处理后6个性状的平均值都增大了。株高、穗颈长、剑叶角度、倒二节间长和倒三节间长的GA3敏感性均是籼稻高于粳稻。绝大部分资源倒二节间长GA3敏感性高于倒一节间长和倒三节间长。聚类分析表明:扬稻6号等9份资源被聚为株高对外源GA3敏感性高的一类;中籼糯等4份资源被聚为穗颈长对外源GA3敏感性高的一类;滇屯502选早等4份资源被聚为剑叶角度对外源GA3敏感性高的一类。筛选出的资源为异交相关性状对外源GA3敏感性的改良和遗传研究提供了材料信息。  相似文献   
77.
将转基因大豆、玉米和水稻的主要外源Cry1A(B)基因、BAR基因、CP4-EPSPS基因、PAT 基因和内参RBCL基因目标片段分别克隆到克隆载体pMD18-T中,构建获得的质粒可作为定性检测3种转基因粮食作物的上述外源基因的通用标准分子质粒pMD18-T-PAT-CP4-EPSPS-Cry1A(B)-BAR-RBCL,长约4.7 kb.经过双酶切、测序及PCR扩增,获得与预期片断大小及序列一致的目的基因片段,证明所构建的标准分子质粒是正确的,可以用来作为不同品种转基因粮食作物定性检测CP4-EPSPS基因、Cry1A(B)基因、BAR基因和PAT基因的通用阳性标准分子.  相似文献   
78.
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   
79.
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   
80.
硅肥对水稻增产提质抗病虫的影响研究进展   总被引:3,自引:0,他引:3  
在"两减一增"目标下的农业生产要打破常规的惯性思维,科学布局;在减少使用化肥农药的情况下,笔者认为可以通过合理施用硅肥来实现稳产增产。本文综合阐述了硅肥施用对水稻增产提质,提高水稻对病虫害的抗性以及对重金属镉吸收转运的影响,使广大稻农意识到使用硅肥的重要性。  相似文献   
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