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排序方式: 共有1616条查询结果,搜索用时 15 毫秒
1.
DREB(Dehydrate responsive element binding factor)转录因子是植物非生物逆境适应中的关键调节因子,该类转录因子具有保守的AP2/EREBP结构域,在低温、高盐等非生物逆境胁迫下,可调控下游逆境应答基因的表达,对增强植物的抗逆能力有重要作用。黑果枸杞具有极强的耐干旱、盐碱能力,为研究黑果枸杞DREB类基因在低温、盐碱响应中的功能,本研究以强抗盐灌木黑果枸杞总RNA为模板,基于前期转录组测序拼接序列,利用RT-PCR方法克隆得到一条DREB基因。该基因含有一个1116 bp的开放阅读框,编码372个氨基酸。系统进化树分析显示,Lr DREB1基因属于DREB亚家族A2组成员,与拟南芥AtDREB2B、AtDREB2E具有较高的相似性。荧光定量PCR结果显示,Lr DREB1受盐胁迫、ABA胁迫和低温胁迫诱导表达,可能参与依赖ABA的信号转导途径,调节黑果枸杞抗盐响应。本研究通过对黑果枸杞LrDREB1基因的克隆、序列分析和表达分析,为研究Lr DREB1的功能及黑果枸杞抗盐机理提供了帮助。 相似文献
2.
Sameer Kumar Chanda Venkata Ganga Rao Nadigatla Veera Prabha Rama Rachit K. Saxena Kulbhushan Saxena Hari D. Upadhyaya Moses Siambi Said N. Silim Kothapally Narasimha Reddy Anupama J. Hingane Mamta Sharma Shivali Sharma Stephen Dominic Lyimo Rose Ubwe Meshack Makenge Kananji Gad Paul Kiprotich Kimurto Manuel Amane Kennedy Kanenga Yuventino Obong Emanuel Monyo Chris Ojiewo Nagesh Kumar Mallela Venkata Jaganmohan Polineni Rao Prashanthi Lakkireddy Sudhakar Chourat Indraprakash Singh Sobhan Sajja Shruthi Hirikara Beliappa Rajeev K. Varshney 《Plant Breeding》2019,138(4):445-454
In the past five decades, constant research has been directed towards yield improvement in pigeonpea resulting in the deployment of several commercially acceptable cultivars in India. Though, the genesis of hybrid technology, the biggest breakthrough, enigma of stagnant productivity still remains unsolved. To sort this productivity disparity, genomic research along with conventional breeding was successfully initiated at ICRISAT. It endowed ample genomic resource providing insight in the pigeonpea genome combating production constraints in a precise and speedy manner. The availability of the draft genome sequence with a large‐scale marker resource, oriented the research towards trait mapping for flowering time, determinacy, fertility restoration, yield attributing traits and photo‐insensitivity. Defined core and mini‐core collection, still eased the pigeonpea breeding being accessible for existing genetic diversity and developing stress resistance. Modern genomic tools like next‐generation sequencing, genome‐wide selection helping in the appraisal of selection efficiency is leading towards next‐generation breeding, an awaited milestone in pigeonpea genetic enhancement. This paper emphasizes the ongoing genetic improvement in pigeonpea with an amalgam of conventional breeding as well as genomic research. 相似文献
3.
Shekhar Shashank Mailapalli Damodhara Rao Raghuwanshi Narendra Singh Das Bhabani Sankar 《Paddy and Water Environment》2020,18(1):73-85
Paddy and Water Environment - Alternate wetting and drying (AWD) irrigation practice in paddy cultivation requires a safe soil moisture stress level in the root zone for which irrigation water... 相似文献
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磷素环境与马褂木种源的生长和干物质积累 总被引:5,自引:0,他引:5
自然土壤中有效磷含量很低,难以满足植物最佳生长的需要。据统计,在全世界13·19亿hm2的耕地中约有43%缺磷,而我国耕地则有2/3缺磷(何绪生等,1998)。我国南方地区高温多雨,富铝化作用明显,多数土壤呈酸性或强酸性,磷素固定强烈,土壤有效磷含量仅在1~2mg·kg-1(邱燕等,2003)。虽然施用磷肥的效果显著,但其利用率一般不超过10%,多为土壤固定并转变成植物较难吸收的Ca-P、Fe-P和Al-P等(熊毅,1997)。鉴于植物具有将土壤难溶态磷转化为有效态磷并加以吸收利用的能力,通过选育磷高效利用的植物品种来开发土壤中难溶态的磷素资源,可减小对施用磷… 相似文献
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Agroforestry Systems - A large number of people in developing countries have traditionally depended on products derived from plants, especially from forests, for curing human and livestock... 相似文献
9.
Investigations on the antinociceptive activity of crude extracts from Croton cajucara leaves in mice
The crude leaf extracts of Croton cajucara Benth. were studied for their antinociceptive property in chemical and thermal models of nociception in mice. All the tested extracts (hexanic, chloroformic and methanolic), at oral doses of 100 and 200 mg/kg demonstrated significant inhibition of acetic acid-induced writhing and the second phase response of formalin, but did not manifest a significant effect in hot-plate test. 相似文献
10.
P. S. Shanmugam R. Balagurunathan N. Sathiah N. G. V. Rao 《Journal of pest science》2007,80(3):175-181
Cotton bollworm, Helicoverpa armigera Hubner selected for five generations with Bacillus thuringiensis insecticidal crystal protein Cry1Ac in the laboratory developed 12.98-fold resistance. Resistance and susceptible populations
were mass crossed to study the dominance of resistance. The Cry1Ac—selected (BCR) population showed 5.8-fold resistance to
Cry1Aa and 5.04-fold resistance to Cry1Ab. The degree of dominance (D) was 0.34 and 0.40 for the R × S and S × R hybrids, respectively, which indicates incomplete recessive character of Cry1Ac resistance in the population. The estimated
realized heritability (h
2) and response quotient (Q) of resistance for Cry1Ac were 0.52 and 0.15, respectively. This indicated the lower phenotypic variation in the selected
population. The resistance risk assessment based on h
2 indicated that the resistance would increased tenfold after <9 generations for Cry1Ac in the resistant population. The results
show the ability of H. armigera to develop resistance against Cry1Ac and cross-resistance to Cry1Aa and Cry1Ab. 相似文献