Toxicity nanoinsecticide based on clove essential oil against Tribolium castaneum (Herbst)

This study aimed to characterize nanoparticles loaded with clove (Syzygium aromaticum) essential oil-based polyethylene glycol (PEG) and to know their insecticidal activity against red flour beetle (Tribolium castaneum). The nanoparticles have irregular shapes in good dispersion. The nanoformulation could not enhance clove oil contact toxicity to T. castaneum, but could protect the oil from degradation and evaporation while simultaneously allowing sustained release, as indicated by the continued high toxicity for 16 weeks of storage.     

Macrophomina phaseolina–host interface: Insights into an emerging dry root rot pathogen of mungbean and urdbean,and its mitigation strategies

The necrotrophic fungus Macrophomina phaseolina is an important pathogen of many crops, such as strawberry, maize, sorghum, potato, soybean, chickpea, and pigeon pea, and causes multiple diseases throughout the world. The microsclerotia, which are the source of primary inoculum, play an important role in the survival and spread of M. phaseolina, as well as disease initiation and development. South Asia has unique characteristics relative to countries with temperate climates, that is, warm temperature, high humidity, and reduced rainfall that influence the interaction between M. phaseolina and its hosts. This review discusses the distribution pattern, pathogen background, pathogenic and genetic variability, and the mitigation strategies applied worldwide to reduce the impact of diseases caused by M. phaseolina with a focus on dry root rot of mungbean and urdbean in South Asia. Dry root rot, caused by M. phaseolina, is an emerging disease of mungbean and urdbean in South Asia. Dry root rot research in South Asia has focused mostly on adopting disease mitigation strategies evolved in tropical to temperate climates such as cultural practices, chemical control, genetic resistance, and biological control. Although the disease is prevalent in most of South Asia, there have been very few studies on M. phaseolina and its host–parasite interaction. Therefore, additional research is required in this domain, which could result in improved understanding and management of M. phaseolina in the face of present and future climate extremes.     

核桃青皮提取物对6种植物病原真菌的抑菌活性研究

采用5种溶剂对核桃青皮进行平行提取和液—液萃取。以苹果轮纹病菌、苹果腐烂病菌、桃褐腐病菌、苹果斑点落叶病菌、茄子枯萎病菌、小麦赤霉病菌6种病原真菌为靶标,对核桃青皮不同溶剂提取液进行抑菌活性测定。结果表明,核桃青皮水提取液对供试的6种病原真菌抑制效果最好,抑制率达到96%以上,石油醚提取液对供试的6种病原真菌抑制效果最差;核桃青皮甲醇提取物氯仿萃取物对桃褐腐病菌的抑制效果最好,抑制率为71.54%,乙酸乙酯萃取物对小麦赤霉病菌的抑制效果最差,抑制率仅为18.32%。     

杧果种质资源若干植物学数量性状评价指标探讨

为建立或完善中国数量化、规范化的杧果种质资源描述系统,以便更好地为中国杧果种质资源的研究工作服务,2007～2009年7月,在海南儋州市中国热带农业科学院热带作物品种资源研究所杧果种质圃内进行杧果品种(种质)资源的叶片长度、叶片宽度、叶柄长度、花序长度、花序宽度、花直径、果实纵径、果实横径、果实侧径、核长度、核宽度和核厚度等12项植物学数量性状指标的测定.结果表明, 12个数量性状均存在10%以上的变异系数,叶柄长度、果实纵径和果核长度呈偏态分布,其他9项呈正态分布.根据分析结果,提出了性状分级标准,建议将12个植物学数量性状分为1～5个等级,每个等级提出2个参照品种,1个国外品种,1个国内品种.该研究为中国杧果种质资源描述系统数量化、规范化的建立或完善奠定基础.     

土壤处理对连作西洋参生长及根病发生的影响

采用田间随机区组试验,选择前茬种过西洋参的老参地,用大扫灭、二硫化碳、多菌灵等3种低毒化学农药和紫苏根作为添加物进行土壤处理,处理后播种西洋参,调查出苗、存苗、根的生长及根病情况。探讨化学农药及植物添加物处理老参地土壤对改善重茬西洋参生长及减少病害的作用。试验结果表明,98%大扫灭粉剂5g/m2~15g/m2、二硫化碳液剂20ml/ m2进行土壤熏蒸处理,对提高重茬西洋参的出苗率、保苗率、产量,以及减轻根部病害均有较好的效果;添加紫苏根50g/m2~100g/m2的作用主要表现为可以提高根重,多菌灵消毒的作用效果不明显。     

土壤处理对连作西洋参生长及根病发生的影响

采用田间随机区组试验,选择前茬种过西洋参的老参地,用大扫灭、二硫化碳、多菌灵等3种低毒化学农药和紫苏根作为添加物进行土壤处理,处理后播种西洋参,调查出苗、存苗、根的生长及根病情况.以探讨化学农药及植物添加物处理老参地土壤对改善重茬西洋参生长及减少病害的作用.98%大扫灭粉剂5～15g/m2、二硫化碳液剂20ml/m2进行土壤熏蒸处理.对提高重茬西洋参的出苗率、保苗率、产量,以及减轻根部病害均有较好的效果;添加紫苏根50～100g/m2的作用主要表现为可以提高根重,多菌灵消毒的作用效果不明显.老参地使用土壤熏蒸剂及适宜的植物添加剂,对克服西洋参连作障碍具有一定作用.     

猪屎豆属植物的利用价值及开发前景

从我国猪屎豆属植物的植物学特征、药用价值、培肥土壤、水土保持等方面,论述了猪屎豆植物的价值,并对其开发利用前景进行了展望。     

我国植物源农药研究进展

随着人们对化学农药的高毒、高残留、害虫抗药性、杀伤天敌、环境污染、危害人类健康等问题的广泛关注,研究和开发环境友好农药成了人们的迫切需要,生物农药特别是植物源农药成了研究热点.概述了发展植物源农药的时代背景及其必要性;植物源农药的特点、种类、研究现状、开发模式及目前存在的一些问题,并对其发展趋势做了一个简单的展望.     

Bioactivity of extracts and isolated compounds from Vitex polygama (Verbenaceae) and Siphoneugena densiflora (Myrtaceae) against Spodoptera frugiperda (Lepidoptera: Noctuidae)

The effects of crude extracts, fractions and isolated compounds from Vitex polygama Cham. and Siphoneugena densiflora Berg were evaluated on the development of Spodoptera frugiperda JE Smith, a destructive insect pest of corn and several other crops. The extracts and fractions were incorporated into an artificial diet at 1 mg g(-1) and offered to the insect during its larval stage. Length and viability of larval and pupal stages as well as pupal weight were assessed. Isolated compounds were tested through superficial contamination of the diet at 0.1 mg g(-1). Weight and viability of ten-day-old larvae were determined. Methanolic and hydroalcoholic S. densiflora extracts caused 100% larval mortality, while leaf and fruit hydroalcoholic extracts from V. polygama were the most active. Among the isolated compounds, flavonoids presented the best insecticidal results, and tannins the best larval growth inhibition.     

甘肃河西五种甘草属植物的植物学特性及药用价值研究

为探索5种甘草属植物在甘肃河西地区的生态适应性及药用价值,以栽培甘草、胀果甘草、光果甘草、刺果甘草及黄甘草为研究对象,对其植物学特性及根部甘草酸、甘草苷含量进行比较研究。结果表明,在甘肃河西地区栽培的5种甘草属植物学特性差异明显;刺果甘草主茎高、小叶数及地上部分鲜重最高,黄甘草居最低水平;甘草根长显著高于其他4个种,但根部鲜重与光果甘草、胀果甘草及刺果甘草无显著差异;甘草酸、甘草苷含量均为3年生比2年生显著增加;3年生根中甘草酸含量除刺果甘草含量最低,其他4个种均达到药典标准,而甘草苷含量则只有甘草达到药典标准。综合各农艺性状和活性成分指标,认为在甘肃河西荒漠化地区,甘草具有较好的生态适应性,可作为甘草药材的基源植物推广种植,而刺果甘草则可作为河西地区重要的防风固沙作物。