首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
"绿色"农产品已经成为当今人类的主要关注点,而"绿色"的关键在于植物保护的思想、技术和策略。本文总结了农业生产模式的4个阶段:原始农业、传统农业、化学农业和物理农业,论述了农业生产模式及其与植物保护思想发展的关系,详细阐述了这4种农业生产模式下植物保护思想的产生、发展和变化的过程。同时,重新排序了IPM植保工程的5项措施:植物检疫、农业防治、物理防治、生物防治和化学防治。强调针对不同作物,制定标准化的IPM工程操作体系,以确保农产品的绿色品质。  相似文献   

3.
4.
不同土地利用类型植物根系与土壤抗蚀性关系研究   总被引:4,自引:0,他引:4  
对紫色土四种土地利用类型耕层土壤中植被根系分布特征进行量化分析,并在此基础上揭示根系分布与土壤抗蚀性评价指标的内在关系,以明确根系对土壤抗蚀性的影响机理.结果表明:小径级根系特别是径级<1 mm的根系对于<0.25 mm土壤团聚体形成和<0.5 mm土壤团聚体形成均有促进作用;<0.5 mm的根系长度与结构体破坏率、团聚状况、< 0.001 mm颗粒含量和<0.01 mm颗粒含量均显著相关;竹林地根系含量最为丰富,<0.5 mm根系平均长度值最大,土壤团粒结构最好,其抗蚀性最强,传统农耕地根系稀少,其抗蚀性最差.  相似文献   

5.
根据国内、外有关植物挥发性次生物质(HIVs)的研究成果,概述其在植物-害虫-天敌三重营养关系中的作用、性质、诱导机制及植物分子调控机理.  相似文献   

6.
2007年10月,以干旱区山麓带新疆伊犁伊宁县金山地区28个样方调查资料为基础,选用Shan-non-Wiener和Si mpson综合多样性指数、Margalef丰富度指数、Herlbert多样性指数(种间相遇几率PIE)以及Pielou均匀度指数和土壤电导率、土壤含水率、土壤pH、土壤全盐量以及各种盐分、土壤有机质、养分共19个土壤因子进行回归分析。结果表明:土壤平均含水率与Pielou均匀度指数二项式回归达显著相关(P=0.037),土壤平均pH与Shannon指数和Herlbert多样性指数的二项式回归均达显著水平(P=0.049,P=0.044),Herlbert多样性指数和Shannon指数与0-20cm土壤的全盐量直线回归有极显著相关性(P=0.003,P=0.005),与20-40cm土壤的全盐量直线回归有显著相关性(P=0.01,P=0.04),与土壤电导率的直线回归有极显著相关性(P=0.001,P=0.001),与0-20cm和20-40cm土壤HCO3-有显著相关性(P=0.03,P=0.015;P=0.047,P=0.05),与0-20cm Ca2+表现为极显著相关(P=0.001,P=0.001)与20-40cm Ca2+土壤显著相关(P=0.021,P=0.078),Shannon多样性指数与0-20cm土壤有机质含量有较显著相关性(P=0.048)。  相似文献   

7.
The following are extended summaries of Technical Reports which are produced at intervals by the International Union of Pure and Applied Chemistry (IUPAC). They are entirely the responsibility of IUPAC/the authors and do not necessarily reflect the views of the Editorial Board of Pest Management Science. Copyright © 2002 Society of Chemical Industry  相似文献   

8.
Heterokaryon compatibility was tested by pairing complementary auxotrophic mutants of three fluctuating (M18, M33 and M50) and three progressive (PV1, PV2 and PV3) hop wilt isolates of Verticillitim albo–atrum . The criteria of compatibility adopted were prototrophic growth on a glucose minimal medium at 26°C and the presence of diploid conidia. Most pairings produced at least some heterozygous diploids, showing there was no complete incompatibility barrier to hyphal and nuclear fusion on an agar medium. The incidence of prototrophic diploidy was greater within paired mutants of progressive isolates, and between PV1 and the three fluctuating isolates. A recombinant haploid prototroph was re–isolated following inoculation of Antirrhinum plants with a pair of complementary auxotrophs (M18 nic -4 cob -26 and PV3 arg -8 pyr -2). In hop, this recombinant was of intermediate pathogenicity compared with the two parental wild–type isolates. Four large–spored, diploid isolates were obtained from Antirrhinum following inoculation with heterozygous diploid conidia (M18 nic -4 cob -26/PV3 arg -8 pyr -2) from diploids synthesized on agar. All four diploids remained stable on agar and one showed moderately high pathogenicity in hop, from which it was re–isolated as a stable diploid 10 weeks later.  相似文献   

9.
通过15种植物病原真菌的培养滤液对草坪杂草稗草、反枝苋、蒲公英、车前、苘麻进行种子萌发抑制试验,对其除草活性进行了初步研究。结果表明:玉米小斑病菌、黄瓜黑星病菌的培养滤液对稗草、蒲公英、车前都表现出显著的除草活性;玉米大斑病菌的培养滤液仅对稗草和蒲公英表现显著的除草活性;烟草赤星病菌的培养滤液仅对车前和苘麻表现了显著的除草活性。安全试验表明:烟草赤星病菌的培养滤液对黑麦草和早熟禾种子的萌发、芽和根的生长表现安全;黄瓜黑星病菌的培养滤液仅对黑麦草种子的萌发、芽和根的生长表现安全。  相似文献   

10.
Pathogenic variability of 14 Septoria tritici isolates from different locations in the USA (California, Oregon, and Texas) was determined on seedlings of two sets of geographically diverse wheat cultivars under greenhouse conditions. Significant isolate effects, cultivar effects, and isolate × cultivar interactions were found, and a substantial amount of variation was accounted for by the interaction terms compared with the main effects of isolate and cultivar. All isolates were pathogenic on the cultivars tested but the degree of virulence on the individual cultivars varied among isolates. Linear contrasts between all homologous combinations (isolate × cultivar combination of same geographic location) and all heterologous combinations (isolate × cultivar combination of different locations) indicated that homologous combinations produced significantly more disease than heterologous combinations. The results demonstrate location-specific adaptation of S. tritici. Implications of pathogenic variability and local adaptation in S. tritici are discussed.  相似文献   

11.
 首次测定了我国水稻条纹叶枯病常年流行区的云南楚雄(CX)及病害暴发区的江苏洪泽(HZ)的RSV 2个分离物RNA1片段的全长序列,这2个分离物RNA1片段的全长序列均为8970 nts。同源性分析结果表明,HZ与日本T分离物的亲缘关系较CX与T分离物的亲缘关系更为接近。通过对纤细病毒属病毒RNA1编码的依赖于RNA的RNA聚合酶(RdRp)氨基酸序列分析的结果表明,该蛋白除了具有RNA聚合酶特征的基元序列结构外,还存在mRNA的转录过程中所采取的加帽起始机制的保守性结构域位点,这表明,纤细病毒属病毒和布尼安病毒科病毒及甲型流感病毒一样,都是采取加帽起始机制进行转录的。  相似文献   

12.
本文简要概述了进出境动植物检疫相关基础设施建设的必要性和建设内容,分析了当前我国进出境动植物检疫基础设施建设存在的主要问题,并提出了推进进出境动植物检疫基础设施建设的建议。  相似文献   

13.
为明确欧洲葵螟Homoeosoma nebulellum Denis et Schiffermüller寄主选择的物理机制,通过对14个向日葵品种(系)筒状小花及瘦果的形态指标观察,采用籽粒被害虫情指数进行田间寄主选择性试验,研究了向日葵的形态性状和欧洲葵螟寄主选择的关系。欧洲葵螟对不同向日葵品种(系)具有明显的选择性,且对食葵品种(系)的选择性均显著高于油葵品种(系)。食葵瘦果多为中长或长形(≥1.5 cm),油葵瘦果则属于短或特短形(<1.5 cm)。向日葵各形态指标在不同品种(系)间均存在极显著差异,食葵的花盘直径、筒状小花开口、子房壁厚度、瘦果果壁厚度、瘦果果壁茸毛密度均大于油葵,且各指标与籽粒被害虫情指数之间、各指标互相之间也均呈显著正相关关系。表明选育较小花盘的向日葵品种(系)可减少葵螟对向日葵的为害。  相似文献   

14.
Using potato, eggplant and thorn apple as test plants, the relationship between soil inoculum density and plant infection was studied as a basis for the development of a quantitative bioassay of Verticillium dahliae. A linear relationship was demonstrated (P < 0.05) between soil inoculum density and population density on roots for all three test plants and for soil inoculum density and population density in sap extracted from stems for eggplant. Correlation coefficients were higher with densities on or in roots (R2 varying from 0.45 to 0.99) than with densities in stems (R2 varying from 0.04 to 0.26). With eggplant, population densities on/in root and in sap extracted from stems were significantly correlated at 20 and 25°C with Pearson's correlation coefficients of 0.41 and 0.53, respectively. For potato, root colonization was higher at 15 than at 20°C, whereas the reverse applied to eggplant. Stems of potato were less colonized than stems of eggplant. The pathozone sensu Gilligan (1985) was calculated to be <300 µm, indicating that infection was caused by microsclerotia which were located close to the roots. To assess the density of V. dahliae in plant tissue pipetting infested plant sap on solidified ethanol agar medium without salts yielded higher densities than using pectate medium or mixing sap with molten agar. A bioassay for determining effects of (a)biotic factors on development of V. dahliae in the plant is recommended with eggplants as a test plant, grown in soil infested with 300 single, viable microsclerotia g-1 soil at a matric potential of –6.2 kPa, and incubated at 20°C for 8 weeks.  相似文献   

15.
草地贪夜蛾卵块在玉米植株上的空间分布   总被引:1,自引:0,他引:1  
本研究调查了草地贪夜蛾卵块在田间玉米植株上的空间分布,发现草地贪夜蛾卵块主要分布于植株中部,即玉米小喇叭口期倒3叶与倒4叶、吐丝期倒5叶与倒6叶上卵块最多,在小喇叭口期主要分布在叶正面,吐丝期主要分布于叶背面,距叶尖平均距离分别为23.4 cm和35.2 cm。为玉米上草地贪夜蛾卵的调查和防治提供了参考。  相似文献   

16.
上海局截获的三种白蚁   总被引:2,自引:1,他引:1  
郑建中  叶军 《植物检疫》1997,11(4):231-234
本文叙述了从缅甸的原木中及美国的废纸中截获的三种白蚁,它们分别是暗黄大白蚁Macrotermesgilvus(Hagen),黄球白蚁Globitermessulphureus(Haviland)和北美散白蚁Reticulitermesflavipes(Kolar)。  相似文献   

17.
进出境动植检工作在国民经济社会发展中发挥了重要作用,本文分析了影响评价动植检工作作用的四种关系,提出了进一步提升进出境动植检工作作用的建议。  相似文献   

18.
随着跨境电商的高速发展,动植物疫情传入我国的风险也在不断加大。本文分析了在此背景下,检验检疫部门在资源配置、法律依据、监管细则、关检合作等方面存在的问题。通过在风险管理的基础上创新监管模式,深化与海关等部门的合作,拓宽检疫宣传的新渠道,推进动植物检疫法的修订工作等多种手段加强对跨境电商动植物检疫的监管,防止疫情疫病通过跨境电商渠道传入我国。  相似文献   

19.
20.
The theoretical relationship between rainfall intensity, raindrop size distribution and the upward transport of splash droplets is examined to establish a better understanding of the natural rainfall characteristics that can cause upward movement of plant pathogens in a crop. The theory suggests that splash transport is determined by the rain splash intensity index, which is defined as the intensity of the rainfall with raindrops greater than a threshold size. Ulbrich's (1983) empirical model of the size distribution of raindrops is used to calculate the relationship between rainfall intensity and rain splash intensity index. The calculations show that rainfall intensity is not a reliable indicator of the rain splash intensity index, particularly in convective showers. Therefore, a correlation between rainfall volume and upward disease progress is unlikely to provide a reliable basis for forecasting sudden disease outbreaks associated with short-duration convective showers during the summer. Finally, we consider the instruments that have the capability to measure the rain splash intensity index.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号