Integrated application of some compatible biocontrol agents along with mustard oil seed cake and furadan on Meloidogyne incognita infecting tomato plants

INTRODUCTION Tomato (Lycopersicon esculentum, Mill.), an important vegetable crop is heavily attacked by root knot nematode, Meloidogyne spp. For the manage-ment of root knot nematodes although chemical nematicides were used till 1982, due to their high cost, toxic effect on beneficial soil borne microorganism and carcinogenic effect on human beings alternative approaches are practiced mainly through eco-friendly means like biological control agents, organic amendments, etc. (Singh and …     

Purification and characterization of a novel antifungal protein from Bacillus subtilis strain B29"

An antifungal protein was isolated from a culture of Bacillus subtilis strain B29. The isolation procedure comprised ion exchange chromatography on diethylaminoethyl (DEAE)-52 cellulose and gel filtration chromatography on Bio-Gel P-100.The protein was absorbed on DEAE-cellulose and Bio-Gel P-100. The purified antifungal fraction was designated as B29I, with a molecular mass of 42.3 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), pl value 5.69 by isoelectric focusing (IEF)-PAGE, and 97.81% purity by high performance liquid chromatography (HPLC). B29I exhibited in-hibitory activity on mycelial growth in Fusarium oxysporum, Rhizoctonia solani, Fusarium moniliforme, and Sclerotinia scle-rotiorum. The 50% inhibitory concentrations (IC50) of its antifungal activity toward Fusarium oxysporum and Rhizoctonia solani were 45 and 112 μmol/L, respectively. B291 also demonstrated an inhibitory effect on conidial spore germination of Fusarium oxysporum and suppression of germ-tube elongation, and induced distortion, tumescence, and rupture of a portion of the germi-nated spores.     

襄麦冬粗提物抗菌活性初步研究

以蒸馏水、甲醇、乙酸乙酯为溶剂,提取襄麦冬活性物质,并分别测定提取物对以下5种病原真菌：立枯丝核菌Rhizoctonia solani,灰葡萄孢菌Botrytis cinerea,齐整小核菌Sclerotium rolfsii,终极腐霉Pythium ultimum,尖镰孢菌黄瓜转化型Fusarium oxysporum f.sp cucumber菌丝生长和孢子萌发的抑制作用.结果表明襄麦冬的三种溶剂提取物对灰葡萄孢菌、终极腐霉、立枯丝核菌的菌丝生长均具有较强的抑制作用,而上述相同浓度的提取物对齐整小核菌、尖镰孢菌黄瓜转化型的生长未表现出明显的抑制效果.同时,三种溶剂提取物对立枯丝核菌、灰葡萄孢菌、齐整小核菌、终极腐霉、尖镰孢菌黄瓜转化型的孢子萌发均表现出一定的抑制作用.其中,襄麦冬乙酸乙酯提取物较蒸馏水和甲醇提取物对病原真菌的生长和孢子萌发的抑制效果明显.乙酸乙酯提取物相对于蒸馏水、甲醇提取物有较好的抑菌效果.襄麦冬提取物对灰葡萄孢菌、终极腐霉、立枯丝核菌的菌丝生长和立枯丝核菌、灰葡萄孢菌、齐整小核菌、终极腐霉、尖镰孢菌黄瓜转化型的孢子萌发有良好的抑制作用.     

中草药提取物对植物病菌抑制和病害防治作用

测定了中草药对植物病原真菌的室内抑菌作用和田间防效.结果表明,白藓皮对小麦赤霉病、小麦纹枯病菌、小麦黑粉病菌、番茄灰霉病菌、番茄早疫病菌的菌丝生长,对番茄早疫病菌、番茄灰霉病菌、小麦赤霉病菌的孢子萌发具有较强抑制作用,0.2 g/mL白藓皮对番茄早疫病、番茄灰霉病、小麦赤霉病的防效分别为76.3%、82.3%和75.1%;胡椒对小麦纹枯病菌、小麦黑粉病菌、番茄早疫病菌、山芋黑疤病菌的菌丝生长,对番茄早疫病菌孢子萌发具有较强抑制作用,0.2 g/mL胡椒对番茄早疫病防效为74.5%;甘草对番茄早疫病菌菌丝生长和孢子萌发有较强抑制作用,0.2 g/mL甘草对番茄早疫病防效为70.9%.     

Purification and characterization of a novel antifungal protein from Bacillus subtilis strain B29

An antifungal protein was isolated from a culture of Bacillus subtilis strain B29. The isolation procedure comprised ion exchange chromatography on diethylaminoethyl (DEAE)-52 cellulose and gel filtration chromatography on Bio-Gel® P-100. The protein was absorbed on DEAE-cellulose and Bio-Gel® P-100. The purified antifungal fraction was designated as B29I, with a molecular mass of 42.3 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), pI value 5.69 by isoelectric focusing (IEF)-PAGE, and 97.81% purity by high performance liquid chromatography (HPLC). B29I exhibited inhibitory activity on mycelial growth in Fusarium oxysporum, Rhizoctonia solani, Fusarium moniliforme, and Sclerotinia sclerotiorum. The 50% inhibitory concentrations (IC₅₀) of its antifungal activity toward Fusarium oxysporum and Rhizoctonia solani were 45 and 112 μmol/L, respectively. B29I also demonstrated an inhibitory effect on conidial spore germination of Fusarium oxysporum and suppression of germ-tube elongation, and induced distortion, tumescence, and rupture of a portion of the germinated spores.     

小麦根际细菌数量变化的研究

利用不同培养基测定了小麦不同生长阶段根际细菌的数量。研究结果表明，在小麦生长发育周期中，根际细菌的数量变化有两个高峰：第一个高峰是在越冬期前，恰与小麦冬前分蘖盛期相对应；第二个高峰是在抽穗开花期，恰与小麦绿色面积最大的时期相对应。     

嵌入式技术在温棚环境控制系统中的应用

介绍了以单片机技术为基础,由上位机集中控制的温室大棚环境控制系统。该系统通过传感器对大棚内温湿度和土壤湿度进行采集,并通过微控制器对数据进行处理来有效地控制、调节作物的生长环境。     

萘污染对菖蒲土壤微生物的影响

用根箱法分析了受萘污染的菖蒲根际和非根际土壤中微生物指标.结果表明:萘对土壤细菌和放线菌可能起抑制作用,根系泌氧及短时期根系分泌物等可以减弱萘污染的影响,长时间后非根际的环境比根际环境更有利于细菌和放线菌的生长.萘污染严重抑制土壤真菌的生长,植物根系的泌氧和根系分泌物极大地减弱萘污染对真菌的影响.菖蒲的存在有利于微生物的生长.     

多菌灵、井冈霉素及其复配剂对水稻纹枯病菌的增效作用

采用菌丝生长速率法分别测定了多菌灵和井冈霉素及其复配剂对水稻纹枯病菌(Rhizoctonia Sola-ni)的毒力,并用W adley增效比率法评价2种杀菌剂的联合作用。试验结果表明,当多菌灵:井冈霉素按1:4,1:9的比例混配时,其协同作用比率分别为2.27和1.60,表现为增效作用。     

Performance of underground heat storage system in a double-film-covered greenhouse

An underground heat storage system in a double-film-covered greenhouse and an adjacent greenhouse without the heat storage system were designed on the basis of plant physiology to reduce the energy consumption in greenhouses. The results indicated that the floor temperature was respectively 5.2℃, 4.6℃ and 2.0 ℃ higher than that of the soil in the adjacent reference greenhouse after heat storage in a clear, cloudy and overcast sky in winter. Results showed that the temperature and humidity were feasible for plant growth in the heat saving greenhouse.     

Phosphate-solubilizing microbes in rhizosphere soils of 19 weeds in southeastern China

Low phosphorus (P) availability is one of the most important factors limiting plant growth in red soils across southeastern China. Many non-symbiotic microorganisms in rhizosphere can enhance P solubility, but little is known about the magnitude of their phosphorus-solubilizing ability (PSA) and the difference in phosphorus-solubilizing microorganisms (PSM) among plant species. The number of phosphorus-solubilizing microorganisms and their PSA in rhizosphere soils of 19 weed species in a citrus orchard on red soil at Changshan, Zhejiang, China, were investigated. Inorganic P (powdered phosphate rock, PR) and organic P (lecithin, OP) were respectively used as the sole P-source to examine the PSA of isolated microbes. The PS actinomycetes community varied greatly among the different weed rhizospheres while the PS fungus community showed to be most stable to the weed rhizosphere. The highest number of PR-PS and OP-PS bacteria was found in rhizosphere soil of Mollugo pentaphyll, and the highest number of PR-PS and OP-PS actinomycetes was found in rhizosphere soil of Polygonum lapathifolium. The highest number of PR-PS fungi was found in Erigeron annuus and Mollugo pentaphyll rhizosphere soil, and the highest number of OP-PS fungi was found in rhizosphere soil of Mazus stachydifolius. Mazus stachydifolius showed the strongest PR-PS ability (6340.75μg) while Eragrostis pilosa showed the strongest OP-PS ability (1301.84μg). The PR-PS ability and OP-PS ability of Mollugo pentaphyll was 4432.87μg and 1122.05μg respectively. A significant correlation between the number of PR-PSM and OP-PSM was found. Significant correlation was only found between the PR-PS fungi number and its PSA(r=0.75, P<0.05) and between the number of OP-PS fungi and its PSA(r=0.87, P<0.01}). It indicated that plant species had significant influence on components of the non-symbiotic PSM community and their activity in its rhizosphere soil. Fungi play a leading role in phosphorus solubilization in weed rhizopshere. It suggested that weed conservation could benefit soil microbe development in agroecosystems, especially in the initial stage of agroecosystem development because there is less organic carbon in bare soil. The results suggested that weed conservation could increase PSA of PSM.     

The effect of different initial densities of nematode （Meloidogyne javanica） on the build-up of Pasteuria penetrans population

Pasteuria penetrans will build-up faster where there is a high initial nematode density and can suppress root-knot nematode populations in the roots of tomato plants. The effect of different initial densities of nematode (Meloidogyne javanica) (150, 750, 1500, 3000) and P. penetrans infected females (F1, F3) densities (F0=control and     

基于PLC的综合改善大棚种植环境系统

好的大棚环境对提高大棚蔬菜产量具有积极的指导作用．文章提出了一种自动调节大棚环境的监控系统．该套系统分别对大棚的温度、湿度、含氧量以及光照度进行检测．根据这些数据实时控制空气加湿器、空气烘干器、空调、草帘等设备,使大棚环境达到理想的状态．该套系统可以避免人为控制设备运行时间过长而导致的人力、能源等的浪费,从而达到节能的目的,同时达到理想的控制目标．整个设备都是基于PLC和触摸屏组态软件的自动控制,基本无需人为操作．     

不同碳、氮素营养对玉米纹枯病菌生长的影响

本文研究了不同碳、氮源对玉米纹枯病菌(Rhizoctonia solani)生长的影响.结果表明:最适宜玉米纹枯病菌生长的碳、氮素营养是淀粉、天门冬酰氨,其次是蔗糖、亚硝酸钠及硝酸铵,而此菌对乳糖、鼠李糖及组氨酸、半胱酰氨、硫酸铵的利用能力较差.     

薄皮甜瓜对南方根结线虫的综合抗性评价

目的:研究南方根结线虫对薄皮甜瓜幼苗生长、发病指数的影响,对6种不同品种薄皮甜瓜的综合抗性作出评价。方法:采用6个不同品种的薄皮甜瓜为实验材料,采取盆栽人工接种方式,通过对甜瓜幼苗的植株鲜重、根瘤数、根结指数、卵粒指数、病情指数、根系电导率、根系MDA含量进行测定,并利用隶属函数对此进行综合分析。结果:接种南方根结线虫45 d后,不同品种的甜瓜幼苗长势、发病指数等差异较大。结论:地方栽培的常规品种中,‘九道沟’与‘羊角酥’甜瓜对南方根结线虫的抗性较强,‘绿宝石’、‘苹果酥’以及‘海南3号’甜瓜对南方根结线虫抗性居中,‘甜宝’甜瓜对南方根结线虫的抗性最差。     

Studies on the management of root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex of green gram, Vigna radiata cv ML-1108

INTRODUCTION Green gram (Vigna radiata) is an important short duration pulse crop. Due to its high nutritive value, it is grown throughout the tropical countries of South and Southeast Asia, particularly in India (Vavilov, 1951). Among various pests and diseases, nematodes-fungus disease complex particularly of Meloidogyne incognita and Fusarium oxysporum poses a great problem to the cultivation of pulse crops by inflicting severe yield losses (Perveen et al., 1999; De et al., 2000; …     

Understanding Natural Cause: Children''s Explanations of How Objects and Their Properties Originate

An understanding of natural cause includes the realization that events can occur independently of human activity or intentions. It also often entails realizing that causal mechanisms can be nonobservable or nonobvious. The present research investigated to what extent children ages 4-7 have developed a concept of natural cause. Study 1 examined children's understandings of object origins (e.g., how the sun began); Study 2 probed children's causal understandings of object behaviors and properties (e.g., why rabbits hop and have long ears). In both studies, children by age 4 were sensitive to the natural kind-artifact distinction in their explanations. They mentioned human intervention for human-made artifacts but rarely for naturally occurring things. Moreover, subjects at all ages were able to identify specific kinds of natural cause, including intrinsic causes (such as growth) and inborn nature. Finally, subjects understood the link between nonobvious, internal parts and self-generated activity (e.g., that bones are important for the flight of a bird). Altogether, these results suggest that even preschool children realize that natural causes exist. They contradict Piaget's characterization of young children as artificialistic (believing that naturally occurring things are created by people) and as focused on observable properties.     

沙蚕美拉德反应产物的抑菌活性研究

采用琼脂打孔扩散法进行了沙蚕美拉德反应产物的水溶液对金黄色葡萄球菌、大肠杆菌、蜡质芽孢杆菌、沙门氏菌、绿脓杆菌、黄瓜枯萎病菌、水稻纹枯菌、白菜丝核菌和黑曲霉等九种菌的体外抑菌活性实验,结果表明沙蚕与蔗糖的美拉德反应产物对蜡质芽孢杆菌、大肠杆菌有较强的抑菌效果,对黑曲霉、水稻纹枯菌、金黄色葡萄球菌和绿脓杆菌有一定的抑制效果,而沙蚕与葡萄糖的美拉德反应产物没有明显抑菌效果。     

Using Interactive Technology to Support Students’ Understanding of the Greenhouse Effect and Global Warming

In this work, we examine middle school students?? understanding of the greenhouse effect and global warming. We designed and refined a technology-enhanced curriculum module called Global Warming: Virtual Earth. In the module activities, students conduct virtual experiments with a visualization of the greenhouse effect. They analyze data and draw conclusions about how individual variables effect changes in the Earth??s temperature. They also carry out inquiry activities to make connections between scientific processes, the socio-scientific issues, and ideas presented in the media. Results show that participating in the unit increases students?? understanding of the science. We discuss how students integrate their ideas about global climate change as a result of using virtual experiments that allow them to explore meaningful complexities of the climate system.     

双歧杆菌与嗜酸乳杆菌混合培养时微生态关系研究

通过以短双歧杆菌和嗜酸乳杆菌分别在混合培养和纯培养时的生长速率及产酸性能的比较,研究了这两种菌在混合培养时的微生态关系。结果表明：混合培养可以加快产酸,短双岐杆菌促进嗜酸乳杆菌生长增殖,嗜酸乳杆菌对短双歧杆菌无明显的促进或抑制作用,两菌在混合培养体系中有良好的微生态关系。