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891.
为研究水分胁迫对小麦幼苗部分农艺性状的影响,分析这些性状与干旱胁迫的关系。以‘青麦6号’和‘烟农24’杂交形成的F2:3群体为材料,采用主基因+多基因混合遗传模型对其进行遗传分析。水、旱2种条件下,根长和根鲜重均为1对加性-显性效应主基因模型;茎鲜重、茎干重、根干重、根茎鲜重比和根茎干重比的最适遗传模型不同。干旱胁迫条件下,茎鲜重主基因遗传率为37%,茎干重、根长、根鲜重、根干重、根茎鲜重比及根茎干重比主基因遗传率分别是51%、81%、74%、56%、50%、68%。茎鲜重、茎干重、根干重等性状,尽管检测到主基因,但在水旱条件下遗传模型不同,可进一步研究其遗传规律。 相似文献
892.
Seiichi Furuya Mai Mochizuki Seiya Saito Hironori Kobayashi Tsutomu Takayanagi Shunji Suzuki 《Pest management science》2010,66(11):1268-1272
BACKGROUND: The increasing occurrence of QoI fungicide resistance in Plasmopara viticola (Berk. & MA Curtis) Berl. & DeToni populations is becoming a serious problem in the control of grapevine downy mildew. In Japan, the existence of QoI‐fungicide‐resistant P. viticola was reported in 2009. RESULTS: The QoI fungicide resistance in P. viticola samples collected from vineyards in Japan in 2008 and 2009 was monitored. Resistant P. viticola were detected in the regions where QoI fungicides have been introduced in accordance with the pest management programme, whereas in Hokkaido vineyards, where QoI fungicides have not yet been introduced, QoI‐fungicide‐resistant P. viticola were not found. CONCLUSION: Japan comprises thousands of islands and is physically isolated from other countries by the sea. Monitoring the emergence, incidence and distribution of QoI fungicide resistance in P. viticola populations in Japan is necessary to improve pest management strategies for downy mildew disease in Japanese vineyards. Copyright © 2010 Society of Chemical Industry 相似文献
893.
转基因水稻对稻瘟病的抗性研究 总被引:6,自引:0,他引:6
采用苗期初筛、复筛、抗谱测定和田间自然诱发试验等不同鉴定方法,对经分子检测证明已整合有碱性几丁质酶基因和β-1,3-葡聚精酶基因的22个转化系的转基因水稻植株进行稻瘟病抗性鉴定研究,筛选出对稻瘟病的抗性比原种对照七丝软占有明显提高的一系列转基因水稻品系,其中表现高抗的有来自F4-9转化株系的7个品系。高抗材料的R7代品系,经室内抗谱测定及田间病圃试验结果,仍然表现高抗稻瘟病。本研究通过转基因技术,成功地将优质感病品种改良成高抗品系,研究结果证明了利用基因工程手段培育抗病水稻新品种是一个非常有希望的育种途径。 相似文献
894.
Mapping of genes involved in glutathione, carbohydrate and COR14b cold induced protein accumulation during cold hardening in wheat 总被引:6,自引:0,他引:6
G. Galiba I. Kerepesi A. Vágújfalvi G. Kocsy L. Cattivelli J. Dubcovsky J.W. Snape J. Sutka 《Euphytica》2001,119(1-2):173-177
Using some of the chromosome substitution lines developed from thecrosses of the donor Cheyenne to Chinese Spring we showed that theaccumulation of water soluble carbohydrates during different stages ofhardening was time dependent. Moreover there was a significantcorrelation between the rate of carbohydrate accumulation and the frosttolerance. The expression and regulation of a wheat gene homologous tothe barley cold regulated cor14b gene was compared in frost sensitiveand frost tolerant wheat genotypes at different temperatures. Studies madewith chromosome substitution lines showed that the threshold inductiontemperature polymorphism of the cor14b wheat homologous genewas controlled by loci located on chromosome 5A of wheat, while cor14b gene was mapped, in Triticum monococcum, onto the longarm of chromosome 2Am. Our study on the effect of cold hardeningon glutathione (GSH) metabolism showed that chromosome 5A of wheathas an influence on the GSH accumulation and on the ratio of reduced andoxidised glutathione as part of a complex regulatory function during coldhardening. In addition, the level of increase in GSH content duringhardening may indicate the degree of the frost tolerance of wheat. 相似文献
895.
为了解小麦抗茎腐病的遗传特性,利用数量性状主基因+多基因混合遗传模型分离分析方法,结合苏麦3号/白免3号重组自交系群体2008、2009两年的茎腐病抗性鉴定数据,对小麦茎腐病抗性进行了遗传模型分析。结果表明,此群体的小麦茎腐病抗性是由两对主基因+多基因控制的(E16), 主基因间有加性累加效应,主基因的加性效应为-7.45(2008年)和-6.58(2009年),两个主基因间的互作效应为11.83(2008年)和10.4(2009年),互作效应大于加性效应。小麦茎腐病抗性的主基因遗传率中等偏上,为70.88%(2008年)和71.24%(2009年),多基因遗传率在10%以下。以上结果表明,小麦茎腐病抗性主要是主基因遗传,且遗传率较高,可以通过杂交育种把小麦茎腐病抗性转移到农艺性状优异的品种中去,但在育种中应关注抗性基因间的互作效应,以便选育出优于抗性亲本的材料。 相似文献
896.
897.
陕西省花椒锈病寄主抗病性调查 总被引:2,自引:0,他引:2
对陕西省宝鸡、韩城、凤县和富平等市县的6个花椒Zanthoxylum bungeagum Maxim品种进行了花椒锈病Coleosporium zanthoxyli Diet.et Syd.寄主抗病性田间调查。结果表明,常见栽培花椒品种抗锈病性序列为:米椒油椒大红袍豆椒;野生品种较栽培大红袍抗病。花椒锈病的发生发展与8-10月份气温及秋季降雨量有一定的相关性。 相似文献
898.
899.
Open pollinated progenies from 15 clones of Japanese black pine (Pinus thunbergii), that had been selected for their tolerance to pine wilt disease, were tested by artificial inoculation with pine wood nematode
for six years at a nursery of Kyushu Regional Breeding Office. Family variations in the respective year were all significant.
An analysis of variance across the six years’ tests confirmed highly significant effect of year and of families; however,
the year by family interaction was significant also. Phenotypic and genetic variances estimated from each year’s result were
fitted to a quadratic regression using their mean survival ratio as an independent variable. The variances were greatest at
around 0.5 of the mean survival ratio. Estimated heritability showed a similar trend of change, whereas the peak of the expected
amount of improvement shifted toward the lower survival range: around 0.4, where a greater selection differential was anticipated.
It was concluded that a useful amount of genetic improvement that may be reduced by 30% due to the interaction, would be expected
by prescreening seedlings where the mean survival ratio after inoculation was around 0.25 to 0.6. 相似文献
900.