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121.
The efficacy of Chaetomium globosum as a biocontrol agent against the late blight pathogen Phytophthora infestans was evaluated in potato plants. Among eight Chaetomium isolates evaluated C. globosum isolate Cg-6 showed greater inhibition to mycelial growth of P. infestans in vitro. TLC studies showed that isolate Cg-6 produced an antibiotic called ‘Chaetomin’. Isolate Cg-6 showed greater exo- and endo-glucanase enzyme activity when compared to other isolates. PCR amplification of the ITS region and sequencing of the PCR product confirmed that isolate Cg-6 belongs to the C. globosum group. C. globosum Cg-6 was formulated as a liquid and applied as a tuber, soil and foliar treatment either individually or in combination against Phytophthora infection in potato plants. Among different treatments, combined application of C. globosum as a tuber treatment @ 1 ml/kg of tubers, as a soil application @ 1 ml/kg of Farm Yard Manure (FYM) and foliar spray @ 0.7% resulted in significantly less late blight infection (72%) compared to untreated control (100%) under field conditions. The application of C. globosum resulted in greater tuber yield by reducing late blight infection in two field trials when compared to untreated controls. The study clearly demonstrated the potential use of C. globosum as a biocontrol agent in the management of late blight disease in potato plants. 相似文献
122.
马铃薯包衣技术研究初报 总被引:1,自引:0,他引:1
不同药剂包衣对马铃薯影响不同。用58%甲霜灵锰锌可湿性粉剂、20%病毒A可湿性粉剂包衣可防治马铃薯晚疫病和病毒病,显著提高出苗率和产量。 相似文献
123.
Agroforestry systems provide diverse ecosystem services that contribute to farmer livelihoods and the conservation of natural resources. Despite these known benefits, there is still limited understanding on how shade trees affect the provision of multiple ecosystem services at the same time and the potential trade-offs or synergies among them. To fill this knowledge gap, we quantified four major ecosystem services (regulation of pests and diseases; provisioning of agroforestry products; maintenance of soil fertility; and carbon sequestration) in 69 coffee agroecosystems belonging to smallholder farmers under a range of altitudes (as representative of environmental conditions) and management conditions, in the region of Turrialba, Costa Rica. We first analyzed the individual effects of altitude, types of shade and management intensity and their interactions on the provision of ecosystem services. In order to identify potential trade-offs and synergies, we then analyzed bivariate relationships between different ecosystem services, and between individual ecosystem services and plant biodiversity. We also explored which types of shade provided better levels of ecosystem services. The effectiveness of different types of shade in providing ecosystem services depended on their interactions with altitude and coffee management, with different ecosystem services responding differently to these factors. No trade-offs were found among the different ecosystem services studied or between ecosystem services and biodiversity, suggesting that it is possible to increase the provision of multiple ecosystem services at the same time. Overall, both low and highly diversified coffee agroforestry systems had better ability to provide ecosystem services than coffee monocultures in full sun. Based on our findings, we suggest that coffee agroforestry systems should be designed with diversified, productive shade canopies and managed with a medium intensity of cropping practices, with the aim of ensuring the continued provision of multiple ecosystem services. 相似文献
124.
冬种马铃薯免耕栽培种薯消毒方法试验 总被引:1,自引:0,他引:1
马铃薯免耕稻草覆盖栽培种薯消毒方法试验结果表明,采用生石灰拌种、克露500倍溶液浸种10min、1000g双飞粉+20g甲基托布津+20g多菌灵+1g新植霉素混合粉剂(自制消毒剂)拌种、50%多菌灵500倍溶液浸种10min、70%百菌清500倍溶液浸种10min和500倍高锰酸钾溶液浸种10min等六种消毒方法,均能取得较好的增产效果,比种薯不经消毒处理直接播种增产45.6%~3.3%;从综合效果看,尤以生石灰拌种、克露浸种和多菌灵浸种处理较好,表现为出苗快、成苗率高、产量高、商品率高。 相似文献
125.
126.
综述了马铃薯A病毒(PVA)运动相关蛋白的结构、功能方面的研究进展. 相似文献
127.
FtsH (Filamentation Temperature-Sensitive H)是一种ATP和Zn2+依赖型金属蛋白酶,广泛存在于原核生物和真核生物中,在真核生物中是多基因家族。FtsH具有ATP酶活性、蛋白水解活性和分子伴侣活性,参与多种胁迫反应。从抗旱马铃薯(Solanum tuberosum)二倍体品系H145中分离得到cDNA-AFLP差异片段,利用RACE技术克隆了SoFtsH cDNA全长序列, 并对其进行分析。结果表明, 该序列包含完整的开放阅读框,长为723 bp, 编码129个氨基酸。SoFtsH具有2个铁氧化还原蛋白结合位点,并存在信号肽序列、跨膜区域和Zn2+结合域。SoFtsH基因序列与GenBank数据库中的其他FtsH基因进行同源序列比对, 并构建系统进化树, 发现该基因与番茄、烟草、拟南芥等高等植物FtsH基因同源性达90%以上。半定量RT-PCR和Northern Blot杂交结果表明SoFtsH基因在干旱胁迫下叶片和根系里的表达量明显增加, 且在抗旱品系H145与干旱敏感品系H214中表达模式不同。说明SoFtsH基因在马铃薯抗旱中起作用。 相似文献
128.
129.
马铃薯卷叶病毒外壳蛋白基因克隆转化
及其转基因后代的表达 总被引:4,自引:0,他引:4
根据GenBank中的马铃薯卷叶病外壳蛋白基因(PLRV-CP)全序列,设计一对特异性引物,以马铃薯卷叶病毒RNA为模板,克隆了马铃薯卷叶病外壳蛋白基因,在pBI121的基础上构建了植物表达载体。利用PLO(Poly-L-Ornithine)将PLRV-CP基因导入到马铃薯加工型品种大西洋的原生质体中,获得了转基因后代。在5株转化后代中扩增出长度为610bp的目标DNA片断,说明导入的外源PLRV-CP基因已经整合到马铃薯基因组中。Southern blot分析结果进一步证明了PCR结果的正确性。RT-PCR结果表明,在3株转化后代叶片中具有阳性表达。马铃薯卷叶病毒接种实验结果表明,转基因植株比对照有明显的马铃薯卷叶病抗性 相似文献
130.