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991.
Summary In screening to isolate a full-length copy of a previously isolated cDNA clone, a further three cDNAs were also isolated from
a library prepared from sub-apical swelling-stolon tissue of potato (Solanum tuberosum L.). Sequence analysis showed these clones to be similar to extensin-like protein genes, acyl carrier protein thioesterase
genes and high mobility group protein genes, respectively. A further cDNA, isolated by subtractive hybridisation, was similar
to a tomato cDNA previously isolated on the basis of its down-regulation following nematode infection. While all the newly
isolated genes were expressed in swelling stolons, for most, maximal expression was seen to be in stem tissue. Possible roles
for these genes in the development of potato plants are discussed, as is the significance of gene expression in stems and
stolons to the process of tuberisation. 相似文献
992.
993.
994.
Transgenic Nipponbare which over-expressed a Na+/H+ antiporter gene OsNHX1 was used to compare its growth performance, water status and photosynthetic efficiency with its wild type under varying salinity regimes. Chlorophyll content, quantum yield and photosynthetic rate were measured to assess the impact of salinity stress on photosynthetic efficiency for transgenic and wild-type Nipponbare. Effects of salinity on water status and gas exchange to both lines were studied by measuring water use efficiency, instantaneous transpiration rate and stomatal conductance. Dry shoot weight and leaf area were determined after three months of growth to assess the impacts of salinity on the growth of those two lines. Our study showed that both lines were affected by salinity stress, however, the transgenic line showed higher photosynthetic efficiency, better utilization of water, and better growth due to low transpiration rate and stomatal conductance. Reduction of photosynthetic efficiency exhibited by the wild-type Nipponbare was correlated to its poor growth under salinity stress. 相似文献
995.
《Plant Production Science》2013,16(1):134-138
AbstractA total of 32 rice genotypes carrying different dwarf or semi-dwarf genes were inoculated with the fungus Fusarium moniliforme Sheldon or treated with 50 mg l-1 GA3 in order to select resources resistant to rice bakanae disease from the dwarf materials. The length of the elongated seedlings was measured, and the percentage of death of the seedlings after transplanting to field was also counted. A significant correlation was found between the length of the seedling treated with GA3 and disease injury by bakanae fungus. Rice materials carrying dwarf gene such as sd1 were not only sensitivity to GA3 but also susceptive to rice bakanae disease. Materials carrying dwarf gene d1 were insensitive to GA3 but susceptive to bakanae. On the other hand, all materials carrying d29, sd6 or sdq(t) genes showed resistance to bakanae. The present study indicated that dwarf and semi-dwarf rice materials might be useful resources for improvement of bakanae resistance in rice breeding programs. 相似文献
996.
白菜型无花瓣油菜突变体的花器官形态特征 总被引:7,自引:1,他引:7
在我国白菜型油菜地方品种余井花籽和国外白菜型油菜品种Am032中同时发现了无花瓣突变体。通过对白菜型油菜无花瓣突变体与甘蓝型无花瓣油菜及正常油菜器官形态的鉴定和比较,认为白菜型油菜无花瓣突变体的花瓣缺失突变机制与甘蓝型油菜不同,白菜型油菜无花瓣突变体有花瓣转变成雄蕊的现象,推测白菜型油菜花瓣缺失突变可能与花器官同源异型基因突变有关。 相似文献
997.
提取乙烯诱导香蕉后熟初期的果皮总蛋白和对照果皮总蛋白,进行双向电泳实验,利用ImageMaster软件找出乙烯诱导的香蕉果皮中的差异蛋白点,并且对差异蛋白进行质谱分析,选取一个可能为Ⅲ类酸性几丁质酶(MaCHⅢ)的蛋白进行后续研究.利用MaCHⅢ的肽段信息在NCBI上比对后找到与该蛋白相应的核酸信息,设计PCR反应引物,扩增MaCHⅢ基因,得到DNA全长序列.结果表明,该基因与Ⅲ类酸性几丁质酶的同源性为99%,可以初步确定这个基因为Ⅲ类酸性几丁质酶基因. 相似文献
998.
《Rice》2012,5(1):3
Background
Since whole genome sequences of rice were made publically accessible, the number of articles on new rice genes has increased remarkably. The Committee on Gene Symbolization, Nomenclature and Linkage (CGSNL) of the Rice Genetics Cooperative published the gene nomenclature system for rice and encouraged researchers to follow the rules before publishing their results. The CGSNL provides an on-line registration system for newly identified rice genes to prevent conflicts and/or duplication of gene name in journal articles.Findings
Recently, the CGSNL surveyed genes in the rice WRKY family in published journal articles and found several duplicated gene names.Conclusions
To discuss and resolve inconsistencies in WRKY gene nomenclature, the rice WRKY working group was established and redefined the nomenclature. This report announces the conclusion. 相似文献999.
玉米低钾耐性性状的主基因+多基因遗传分析 总被引:2,自引:0,他引:2
应用植物数量性状主基因+多基因混合遗传模型多世代联合分析方法,以玉米缺钾症状叶片数为指标,对1个耐低钾玉米自交系T和2个低钾敏感玉米自交系S1和S2配制成的2个组合的P1、P2、F1、B1、B2和F2世代进行遗传分析,研究明确玉米耐低钾性状的遗传机制。结果表明,玉米低钾耐性遗传在2个组合中都由1对加性+加性-显性多基因控制;主基因遗传率(F2)平均为60.43%,多基因遗传率(F2)平均为15.35%;T×S1组合的遗传变异占表型变异值为80.20%,T×S2组合的遗传变异占表型变异值为71.35%,表明耐低钾性状以主基因遗传为主。育种应用上可以在低世代进行这一目标性状的选择。 相似文献
1000.