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61.
Cotton is an important cash crop, and achieving disease resistance as well as early maturity is an important breeding goal. However, the molecular relationship between disease resistance and early maturity of cotton is still a research gap. In previous study, we identified a GbSTK gene response to V. dahliae that could enhance Verticillium wilt resistance in transgenic Arabidopsis. In this study, we found that GbSTK was more highly expressed in resistance and/or tolerant varieties than in susceptible varieties. Knocking down of GbSTK expression in Nongda 601 showed that the silenced plants displayed serious disease symptoms, with disease index from 27.5 (tolerant) to 63.2 (susceptible), suggesting that GbSTK positively regulates cotton Verticillium wilt resistance. More interesting, we found that GbSTK could promote the development of Arabidopsis. At the flowering time point, the average number of rosette leaves in transgenic lines was 7.5, significantly less than the mock plants, and the transgenic plants bloomed five to seven days earlier than the control. The FT and SOC1 gene, regarded as marker genes in Arabidopsis flowering signaling pathway, maintained higher expression level in transgenic lines than in the mock, indicating that GbSTK could accelerate flowering via regulating FT and SOC1 gene expression. We also obtained 30 candidate proteins that could interacted with GbSTK via yeast double hybrid test, which helped to further revealing the molecular regulatory network of GbSTK. Taken together, we first identified a functional gene that could improve disease resistance and early flowering, which would provide a reference for genetic improvement of cotton disease resistant and early maturity.  相似文献   
62.
R. S. Pan  T. A. More 《Euphytica》1996,88(2):125-128
Summary Melon germplasm was screened for cucumber green mottle mosaic virus (CGMMV), powdery mildew (Sphaerotheca fuliginea), downy mildew (Pseudoperonospora cubensis) and Fusarium wilt (Fusarium oxysporum f. sp. melonis) resistance under artificial conditions except downy mildew for which screening was done under natural epiphytotic conditions. High level resistance to all the four diseases was not recorded in any of the collections tested. Nevertheless, ertheless, resistance to three diseases was located in three germplasm. Wild Cucumis species C. figarei exhibited absolute resistance to CGMMV and Fusarium wilt and high level resistance to downy mildew. Phoot or snapmelon (Cucumis melo var. momordica) — a non-dessert from of Indian origin—was highly resistant to downy mildew and resistant to CGMMV and medium resistant to Fusarium wilt. Iroquois was resistant to powdery mildew and medium resistant to downy mildew and CGMMV.  相似文献   
63.
丙基双氢茉莉酮酸酯诱导棉花耐黄萎病的效应   总被引:3,自引:0,他引:3  
何茂华  慕卫  刘峰 《棉花学报》2004,16(2):108-111
温室内以10mg·L 1的丙基双氢茉莉酮酸酯(PDJ)灌根预处理后,再用黄萎病菌(Verticilliumdahliae)孢子悬浮液接种棉苗,处理棉苗与对照相比发病率和病情指数有所降低,表现出对棉花黄萎病的耐病性。对一些生化指标进行测定发现,PDJ灌根和接种都可引起棉苗叶片中苯丙氨酸解氨酶(PAL)活性升高和木质素含量的增加,与此同时棉花叶片中的过氧化物酶(POD)活性及丙二醛(MDA)含量也都有所上升,在此基础上对PDJ诱导棉花耐黄萎病的可能生化机制作了归纳。  相似文献   
64.
胡麻枯萎病病原尖孢镰刀菌生态生物型的划分研究   总被引:5,自引:1,他引:5  
通过酯酶同工酶技术将来自中国主要胡麻产区内蒙古、山西、河北、甘肃的17个枯萎病菌株划分4个酯酶型,同时对部分菌株采用人工室内接种同一胡麻材料后的病情进行分析,考察菌株问的致病性。结果表明:同一地区的菌株属于同一酯酶型,同一地区的菌株间的致病性差异不显著,不同地区菌株问的致病性差异显著。  相似文献   
65.
J. Rubio    E. Hajj-Moussa  M. Kharrat    M. T. Moreno    T. Millan  J. Gil 《Plant Breeding》2003,122(2):188-191
The inheritance of resistance to fusarium wilt race 0 of chickpea and linked random amplified polymorphic DNA (RAPD) markers were studied in two F6:7 recombinant inbred line (RIL) populations. These RILs were developed from the crosses CA2156 × JG62 (susceptible × resistant) and CA2139 × JG62 (resistant × resistant), and were sown in a field infected with fusarium wilt race 0 in Beja (Tunisia) over 2 years. A1:1 resistant to susceptible ratio was found in the RIL population from the CA2156 × JG62 cross, indicating that a single gene with two alleles controlled resistance. In the second RIL population (CA2139 × JG62) a 3:1 resistant to susceptible ratio indicated that two genes were present and that either gene was sufficient to confer resistance. Linkage analysis showed a RAPD marker, OPJ20600, linked to resistance in both RIL populations, which is present in the resistant parent JG62.  相似文献   
66.
Inheritance of bacterial wilt resistance in tetraploid potato was investigated in segregating progenies of parent clones with resistance derived from different specific sources and different types of adaptation. A race 1 and a race 3 isolate of Pseudomonas solanacearum were used to test the resistance under warm temperatures. Results obtained indicated partial dominance of resistance. Significant general and specific combining abilities showed that both additive and non-additive gene actions are important in conditioning resistance expression. There was evidence that epistasis is an important component of the non-additive gene action in the inheritance of resistance. Other aspects of the resistance and implications for breeding are discussed.  相似文献   
67.
棉花黄萎病抗性的分子研究进展   总被引:8,自引:3,他引:8  
本文综述了棉花黄萎病菌的分子鉴定,棉花黄萎病抗性的遗传基础,分子标记在棉花抗黄萎病方面的应用,棉花黄萎病抗性基因的克隆及转化等方面的研究进展。  相似文献   
68.
京郊菜豆枯萎病的致病菌,经作者鉴定为尖孢镰刀菌菜豆专化型(Fusarium oQxysporum f.sp.phaseoli).在防治上,我们采用以抗病品种为主的综合防治措施,经过2年多点试验,防治效果显著(92.50—94.73%),增产明显(31.26—34.09%).  相似文献   
69.
Summary A total of 125 novel accessions of Capsicum annuum L. and Capsicum baccatum L. were screened for sources of resistance to Verticillium wilt (Verticillium dahliae Kleb). A soil infestation method with 2000 microsclerotia of V. dahliae per gram of planting medium, and a soil temperature of 25±3°C, identified 27 Capsicum accessions with resistance to Verticillium wilt. P.I. 215699 (a mixture of Capsicum baccatum var. microcarpum and Capsicum annuum), P.I. 535616 (Capsicum annuum), and P.I. 555614 (Capsicum annuum), had the lowest disease severity and the highest percentage of resistant plants.  相似文献   
70.
本文以分子生物学研究手段为纲 ,从RFLP、RAPD、ITS等方面 ,综述了国内外在棉花黄萎病菌种内划分及致病力分化上的研究状况及最新进展  相似文献   
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