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101.
从马铃薯根际土壤中分离筛选得到对立枯丝核菌有较强拮抗作用的菌株XC-1,对其进行鉴定及生防特性分析,并评价其对马铃薯黑痣病的生防效果.形态学、16S rDNA和gyrB基因序列分析以及生理生化检测结果表明,XC-1菌株为枯草芽孢杆菌(Bacillus subtilis).XC-1菌株具有产纤维素酶、蛋白酶及嗜铁素和HC...  相似文献   
102.
丛枝菌根真菌对芋组织培养苗生长的影响   总被引:9,自引:0,他引:9  
李敏  刘鹏起  刘润进 《园艺学报》2002,29(5):451-453
 于温室盆栽条件下研究了丛枝菌根(AM) 真菌Gigaspora rosea、Glomus mosseae 和Glomus versi-forme 对芋(Colocasia esculenta) 组织培养苗移栽成活率、矿质营养、光合速率及生长的影响。结果表明, 接种AM真菌能提高芋组织培养幼苗移栽成活率和叶片光合速率, 降低气孔阻力; 其叶片和根内氮、磷、钾含量和生长量显著高于不接种对照。认为接种有效AM真菌是促进组织培养苗健康生长的重要技术。  相似文献   
103.
Plant volatile compounds, including terpenes, are known to be involved in the rice defense system. In the present analysis of a terpene synthase, OsTPS18, in rice, we found that OsTPS18 was localized in the cytoplasm and synthesized the sesquiterpenes (E)-nerolidol and (E)-β-farnesene. The amounts of (E)-nerolidol and (E)-β-farnesene increased after jasmonic acid (JA) treatment. (E)-Nerolidol had significant antibacterial activity against Xanthomonas oryzae pv. oryzae (Xoo). These results suggest that (E)-nerolidol plays an important role in JA-induced resistance against Xoo and that it functions as an antibacterial compound in rice.  相似文献   
104.
基于GIS的陕西省酿酒葡萄气候区划   总被引:2,自引:0,他引:2  
利用陕西省96个县(区、市)气象站及周边省份临近气象站近30 a(1981—2010年)气象观测资料,辅以经订正后的各县气象哨和水文站观测数据,在对国内外葡萄区划指标分析基础上,确定以≥10℃活动积温为一级指标,酿酒葡萄成熟期8—9月水热系数为二级指标,冬季埋土防寒线、9月降水为辅助指标作为陕西省酿酒葡萄气候区划指标。基于GIS技术,利用小网格推算模型对区划指标空间化后,采用主从叠代方法,制作陕西省酿酒葡萄气候区划图。结果表明,陕西省酿酒葡萄种植可分为4个气候区和12个气候亚区,自兴平以东的关中东部海拔900 m以下地区是陕西省种植酿酒葡萄的最优区;对各区酿酒葡萄生产的气候因子进行了评价,提出了相应的生产建议。  相似文献   
105.
刘联仁 《昆虫天敌》1992,14(2):69-71
梳胫饰腹寄蝇 Blepharipa sckineri 属双翅目寄蝇科。本文记述了它的分布、寄主、形态特征和生物学特性。此蝇是桉树大毛虫 Suana divisa 的主要昆虫天敌,其寄生率高达33~48%,应很好地保护利用。在四川省会理县是一年发生1~2代.以蛹越冬。卵期12~15天,幼虫期24~35天,蛹期18~45天,成虫期10~30天。  相似文献   
106.
The numerical analysis was performed to predict the potential problem, often occurring during the manufacturing process of the disposable medical device of a great volume. The cavity filling analyses were performed for the new design of the 3cc Syringe Barrel using polypropylene(PP1), and a new nucleated polypropylene(PP2) material for better clarity. These analyses have been performed for different processing conditions as well as various wall thickness designs for both materials. With the nucleated material, only the original wall thickness design has been studied at two different processing conditions for comparison purpose. This study was conducted to investigate the optimum part design and processing condition for two different materials. The most desirable design was selected with Design 3 for material utilization and reduced flow stresses by comparing the field results. The new nucleated polypropylene provided slightly better product quality and processing.  相似文献   
107.
The olive fruit fly, Bactrocera oleae (Rossi), is the major olive pest in the Mediterranean Basin, being responsible for high losses in olive production. The objective of this work was to study the influence of B. oleae infestation on the pomological parameters and nutritive value (lipids, proteins, carbohydrates and ash) of eight olive cultivars (Abani, Aellah, Blanquette de Guelma, Chemlal, Ferkani, Limli, Rougette de Mitidja and Souidi) from Algeria. The results displayed different degrees of susceptibility of the studied cultivars to this pest. Fruit size (weight) and the Fruit weight / stone weight ratio are significantly correlated with the attack. The statistical treatment of the results (PCA and HAC) highlighted different behaviors from the cultivars, concerning the attack. There are some cultivars more susceptible, being the nutritional value also affected. The lipid and protein contents were positively correlated with the attack and the carbohydrates negatively, suggesting a careful choice by the B. oleae. Ovipositional preference of olive fruit fly females and the success of larval development in different olive cultivars are crucial to establishing new approaches in Integrated Pest Management (IPM) against this pest.  相似文献   
108.
Frequent windthrow in the strict reserves of spruce in the Kopaonik National Park provides much material favorable for the development of Ips typographus (L.) and Pityogenes chalcographus (L.) (Coleoptera, Scolytidae). Therefore it was assumed that the abundance of these bark beetles in the reserves was high and that they dispersed to the surrounding spruce forests. To verify this opinion, their population levels were monitored in the strict reserve Jankove Bare and the adjoining spruce forests over the period 2006–2008. I. typographus parasitoids were identified and the parasitism percent was determined in spruce forests around the reserves. Throughout the monitoring period, the abundance of I. typographus and P. chalcographus was found to be lower in the reserve than in the surrounding spruce forests. Five species of I. typographus parasitoids and a low parasitization percent were identified in spruce forests surrounding the reserve.  相似文献   
109.
河南商丘地区棉花黄萎病菌分离鉴定和致病力分析   总被引:2,自引:1,他引:2  
为探讨河南商丘地区棉花黄萎病菌的致病型群体变异,对该地区棉花上分离的8株单孢菌株的菌落形态、显微结构、致病力、ITS序列、系统进化及菌体蛋白等方面进行了研究。结果表明:这些菌株均属于棉花黄萎病菌Verticilliumdahliae;系统进化树显示8株菌株并没有聚在同一进化枝上;8株黄萎菌菌株存在致病力差异,SQ4菌株致病力最强,属于落叶型,而其它致病力较弱的7个菌株属于非落叶型;不同致病力的菌株间蛋白谱带存在差异。  相似文献   
110.
Cadmium (Cd) is a widespread environmental toxicant that can cause severe hepatic injury. Oyster protein hydrolysates (OPs) have potential effects on preventing liver disease. In this study, thirty mice were randomly divided into five groups: the control, Cd, Cd + ethylenediaminetetraacetic acid (EDTA, 100 mg/kg), and low/high dose of OPs-treatment groups (100 mg/kg or 300 mg/kg). After continuous administration for 7 days, the ameliorative effect of OPs on Cd-induced acute hepatic injury in Cd-exposed mice was assessed. The results showed that OPs significantly improved the liver function profiles (serum ALT, AST, LDH, and ALP) in Cd-exposed mice. Histopathological analysis showed that OPs decreased apoptotic bodies, hemorrhage, lymphocyte accumulation, and inflammatory cell infiltration around central veins. OPs significantly retained the activities of SOD, CAT, and GSH-Px, and decreased the elevated hepatic MDA content in Cd-exposed mice. In addition, OPs exhibited a reductive effect on the inflammatory responses (IL-1β, IL-6, and TNF-α) and inhibitory effects on the expression of inflammation-related proteins (MIP-2 and COX-2) and the ERK/NF-κB signaling pathway. OPs suppressed the development of hepatocyte apoptosis (Bax, caspase-3, and Blc-2) and the activation of the PI3K/AKT signaling pathway in Cd-exposed mice. In conclusion, OPs ameliorated the Cd-induced hepatic injury by inhibiting oxidative damage and inflammatory responses, as well as the development of hepatocyte apoptosis via regulating the ERK/NF-κB and PI3K/AKT-related signaling pathways.  相似文献   
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