Evaluation of biological control agents for managing cucurbit powdery mildew on greenhouse-grown melon

An evaluation was made of the ability of two mycoparasite-based products AQ10® ( Ampelomyces quisqualis ) and Mycotal® ( Lecanicillium lecanii ), as well as three strains of Bacillus subtilis , to manage powdery mildew disease, caused by Podosphaera fusca on melon seedlings maintained under different regimes of relative humidity and on plants grown under greenhouse conditions in Spain. In every case fungal and bacterial biocontrol agents (BCAs) performed better under conditions of high relative humidity (90–95% RH). In greenhouse experiments, the effectiveness of the mycoparasites to manage powdery mildew was absolutely dependent on mineral oil. The strains of B. subtilis provided disease control similar to that achieved with the mycoparasites or the fungicide azoxystrobin. Microscopic analysis showed the ability of these bacterial strains to efficiently colonize leaf surfaces and revealed the occurrence of antagonistic interactions between biological agents and P. fusca structures. These results confirmed the usefulness of these BCAs for managing powdery mildew on greenhouse-grown cucurbits either as single products or as a component of integrated control programmes.     

Less hazardous alternative herbicides to control weeds in immature oil palm

In 2002, the Malaysian government had banned the use of the hazardous herbicide, paraquat. Most growers perceive that paraquat is the most effective herbicide and provides the fastest mode of action to control weeds. An experiment was conducted at MAB Agriculture-Horticulture, Sepang, Selangor, Malaysia, from February 2004 to February 2005 to evaluate the efficacy and ability of the less hazardous herbicides, glufosinate ammonium and glyphosate, as an alternative to the hazardous herbicide, paraquat, in controlling weeds in immature oil palm (<3 years old). The results showed that paraquat needed high rates, 600 and 800 g ha⁻¹, to control weeds effectively. However, lower rates of glufosinate ammonium (200 g ha⁻¹) and glyphosate (400 g ha⁻¹) gave excellent weed control. The results showed that the efficacy of glufosinate ammonium and glyphosate were much better than paraquat. The results also showed that, with no direct contact with the plants, paraquat, glufosinate ammonium, and glyphosate had no adverse effect on the vegetative and generative growth of oil palm in this study. These results proved that the less hazardous herbicides, glufosinate ammonium and glyphosate, could be used as an alternative to paraquat to control weeds in immature oil palm.     

细辛挥发油抗植物病原真菌活性初步研究

从天然产物包括植物中开发新的高效低毒环境友好型杀虫杀菌剂，是农药领域重要的研究内容。细辛（Asarum）为马兜铃科（Aristolochiaceae）草本植物，是我国特有的传统中药，中医用于治疗风寒头痛、痰饮咳喘、关节疼痛、鼻塞、牙痛、胃炎以及口腔糜烂等。有文献报道，细辛提取物对黄曲霉（Aspergillus sp．）、黑曲霉（Aspergillusr sp．）、人类致病菌白色念珠菌（Candida sp．）、伤寒杆菌（Salmonella sp．）有抑菌作用；对人参黑斑病菌（Alternaria panax）、人参根疫病菌（Phytophthora cactorum）、腐皮镰孢（Fusarium solani）和番茄灰霉病菌（Botrytis cinerea）等植物病原菌具有较好的抗菌效果。有关细辛抗菌机制的研究尚未见报道。本文选择9属16种植物病原真菌进行生物测定，探讨细辛挥发油抗菌的广谱性，并以Alternaria humicola为研究对象，对其抗菌机理进行初步研究，以便为开发新型植物杀菌剂提供理论依据。     

加降凝剂输油技术的现状及发展方向

输油管道添加降凝剂是改善原油代温流变性的一种物理化学方法，从降凝剂的筛选和复配，处理条件，应用方式，配套设施、应用效果等方面系统地介绍了含蜡原油添加降凝剂输送工艺的研究及应用现状，指出了降凝剂在研究和应用中存在的问题，对添加降凝剂的输油技术进行了客观评价，展望了降凝输油技术的发展方向。     

Effect of Synthetic Cytokinin Application on Pod Setting of Individual Florets within Raceme in Soybean

Abstract

The application of synthetic cytokinin (6-benzylaminopurine, BA) to racemes of soybean genotype IX93-100 at 7 days after anthesis (DAA) enhanced pod-set percentage of the florets at the 5th position and above (numbered from the base on rachis). The endogenous cytokinin (trans-zeatin riboside) content of individual florets was measured at the 1, 3, 5, 7th position every 3 days after anthesis. Cytokinin was detected only from the florets at 9 DAA, and the content was higher in the more proximal florets while it became negligible in the 7th floret. These results suggest that an increase in the amount of cytokinin in individual florets might enhance the pod setting of the florets positioned at the middle or distal part within the raceme.     

科技信息在我国食用油产业发展中的作用

讨论了我国食用油产业的发展现状,分析了国际4大粮商渗入我国食用油产业的轨迹,阐述了科技信息在我国食用油产业发展中的作用.     

Influence of Seed Treatment with Uniconazole Powder on Soybean Growth,Photosynthesis, Dry Matter Accumulation after Flowering and Yield in Relay Strip Intercropping System

Abstract

The relay strip intercropping system of wheat-corn-soybean is widely used in southwest China. However, it is hard to produce soybean stably with this system, since the growth of soybean plants is slower under shading by corn at the seedling stage, and it is compensated by accelerated growth after the symbiotic stage. Soybean plants show excessive vegetative growth due to more rain during the flowering stage, which results in fallen petals, fallen pods and lower yield. This study investigated whether seed treatment with uniconazole powder (0, 2, 4 and 8 mg kg^–1 seed) suppresses excessive vegetative growth of soybean plants during the flowering stage and delays senescence of photosynthetically active leaves at the pod-setting stage. If such events are correlated with changes in photosynthesis, they may affect dry matter accumulation and seed yield in the relay stripping system. Uniconazole promoted biomass accumulation from 31 (R₃) to 61 (R₅) days after flowering (DAF) and seed yield. Seed treatment with uniconazole raised the net photosynthetic rate, stomatal conductance, transpiration rate, and total chlorophyll and chlorophyll a contents. In contrast, uniconazole reduced leaf area index (LAI) from 1 DAF (R₁) to 46 DAF (R₄) with the increase in uniconazole concentration, whereas, uniconazole significantly increased LAI at 61 DAF, and the greatest promotion occurred at 2 mg kg^–1 treatment. The study clearly showed that uniconazole effectively suppressed excessive vegetative growth of soybean during flowering stage, delayed senescence of photosynthetically active leaves at pod-setting stage and induced higher yield, which were related to the changes in photosynthetic rate, chlorophyll content, dry matter accumulation and LAI in the relay strip intercropping system.     

库鄯线INERGEN气体自动灭火系统

介绍了库鄯输油道采用的ＩＮＥＲＧＥＮ气体自动灭火系统的组成、特点、工艺及操作主要设备参数以及测试方法等，对该系统的维护及保养提出了几点建议，该系统的建立可有效地保护库鄯输油管道首末站的站控室，通信机房、ＵＰＳ间及减压站的柴油发电机房、配电室，站控室，通信机房及ＵＰＳ间等。     

国际石油贸易计量方法

为符合国际石油贸易市场的计量要求，在石油贸易计量中应掌握不同的标准条件，以进行合理的石油贸易。介绍两种国际上使用的原油静态和动态计量方法，阐述了这两种方法在实际应用中应遵循的有关国际标准。     

粮油食品工艺学课程教学改革探索

粮油食品工艺学是一门理论和实践并重的技术课程,通过教学改革与实践,探讨了改进课堂教学和优化实践环节的方法和成效。