玉米粗缩病发生与玉米地不同前茬类型的关系

玉米粗缩病（ＭＲＤＶ）２０世纪８０年代在思南县玉米作物上仅零星发生 ,２０世纪９０年代中后期其发病面积逐年扩大 ,发病程度呈逐年加重的趋势。据１９９６年调查 ,全县发病面积４６７ｈｍ２,占全县玉米种植面积的５．３８ %。病株率４．６ %～９．４ %。１９９９年全县发病面积已上升到２４６７ｈｍ２ ,占全县玉米种植面积的２８．４６ % ,平均病株率２４．８７ % ,严重地块病株率达３０．４ %。目前 ,全县玉米粗缩病的发生程度已成为玉米病害之首。１９９８年对玉米粗缩病的发生作了初步观察 ,１９９９年对病害的发生与前茬不同类型地…     

2013—2022年山东省玉米主要病虫害发生特点和原因分析

山东是玉米种植大省,随着产业结构调整、秸秆还田等耕作方式的改变,玉米病虫发生了新的变化,对科学防控提出了更高要求。本文总结了近10年来山东省玉米病虫害呈现出的新特点,即发生面广量大,虫害重于病害,玉米螟为害持续严重,棉铃虫为害上升,迁飞性的黏虫重发频次增加,二点委夜蛾、草地贪夜蛾等新发害虫增多,玉米蓟马为害下降,玉米南方锈病和褐斑病等流行性病害重发年份增加,玉米粗缩病为害不断减轻,分析得出玉米及设施蔬菜种植面积增加、棉花种植面积不断减少、秸秆还田、免耕直播、主栽品种抗病虫性差以及极端天气频发是其发生变化的影响因素,提出了今后玉米病虫害监测预警及绿色防控的意见建议。     

乳山市灰飞虱、玉米粗缩病发生概况及发生规律

简述近5年来灰飞虱和玉米粗缩病在乳山市的发生概况,分析灰飞虱、玉米粗缩病的发生规律及发生原因,以便有效地控制灰飞虱和玉米粗缩病的为害。     

玉米粗缩病的发生及防治

玉米粗缩病在石家庄地区早有零星发生。近年来,由于棉麦套种和麦田套种玉米,此病有蔓延趋势。 玉米粗缩病是一种病毒病害,传毒媒介为灰飞虱。飞虱在我区一年发生五代。 发病规律 玉米粗缩病的发生发展,取决于灰飞虱田间数量和带毒个体的多少。灰飞虱的田间消长又与以下栽培条件有密切关系。 1.套种玉米田发病重于单播田:玉米粗缩病的发展是伴随三种三收和麦套玉米面积的扩大而逐年加重。分析造成套种玉米田发病重的原因,一是夏     

乳山市玉米粗缩病的生态防治

玉米粗缩病是乳山市玉米上的常发性病害。2005年该病在乳山市春玉米上发生严重,绝大多数发病植株未能抽穗结实,是近30a来发生最重的年份。为搞好对该病的防治,现将     

邹平县玉米粗缩病的发生与防治

邹平县玉米粗缩病的发生与防治成学美杨先法董家兴马用华成惠珍（山东省邹平县植保站２５６２００）１９９２年以来我县玉米粗缩病（ＭａｉｚｅＲｏｕｇｈＤｗａｒｆＶｉｒｕｓ）危害逐年加重,至１９９６年发病面积达２．６７万ｈｍ２,占玉米播种面积６６．８％,给玉米...     

隆安县玉米粗缩病的发生实况分析和综防对策初探

玉米粗缩病是一种玉米病毒病害,在我国北方和江浙等地较为多见,在华南地区尚鲜有报道。玉米是广西隆安县第二大粮食作物,年种植面积1．2万公顷,21世纪初以来,玉米粗缩病在广西隆安县部分乡镇发生危害,发生面积及范围逐年扩大,对玉米生产构成了潜在危害。作者通过分析隆安县玉米粗缩病的发生实况和特点,总结玉米病毒病综合防控技术措施。     

玉米粗缩病和水稻黑条矮缩病的发生及防治对策

本文根据玉米粗缩病和水稻黑条矮缩病近几年来的发生特点和为害情况 ,具体阐述这两种病害的发病症状、发生规律、病原生物学、发生影响因素、合理的防治措施 ,为今后更好地识别和防治这两种病害提供了理论基础     

滨海县玉米粗缩病发生特点及绿色防控技术的实践

为了有效防控江苏省滨海县玉米粗缩病,从发生规律入手,系统分析了该病害发生特点、为害情况,明确了影响其发生的主要因素,在此基础上探究并形成了一套适合于当地的玉米粗缩病绿色防控技术.通过技术体系的推广应用,显著降低了粗缩病的发生,保障了玉米高产稳产. 2002—2018年,累计减少玉米粗缩病发生面积3 263.11 hm2,共挽回产量损失5 806.88 t,取得了明显的社会、经济和生态效益.     

潍安市玉米粗缩病大发生情况调查

淮安市2004年玉米种植面积8．53万hm^2．有30个左右的玉米品种，以农大108、澄海11号、郑单958、登海9号、白玉109、掖单4号为主体种植品种。2004年玉米粗缩病发生面积1．9万hm^2．占种植面积的55．36％，其中春玉米40％面积发生粗缩病，病株率平均5．6％，夏玉米61．5％面积发生粗缩病，病株率平均15．9％。以农大108、登海11号、郑单958及西玉3号抗病性较好，     

新疆奇台县近42a气候变化特征分析

根据新疆奇台县气象站的气温及降水资料,利用线性趋势函数及M ann-kendall突变检测法分析了该地区近42年的气候变化。结果表明:年平均气温与极端最低气温均呈上升趋势,而极端最高气温呈下降趋势;年降水量呈上升趋势。从季节变化来看,除夏季平均气温呈下降趋势,其它各季平均气温均呈上升趋势,其中以冬季增幅最大,秋季次之;各季降水均呈上升趋势,其中以夏季增幅最大,冬季次之。年平均气温未发生突变,而年降水量在1984年发生由少向多的突变。对气温和降水的异常分析得出,暖温年多发生在上世纪80年代后,冷温年多发生在上世纪60、70年代;多雨年主要在近20年,少雨年则多在上世纪60、70年代。此外,该县近42 a来增暖幅度小于全疆和北疆;增湿幅度大于全疆,小于北疆。     

我国苜蓿病害研究进展

综述了我国苜蓿主要病害的分布和危害、病原学、发生规律、抗性种质材料的遗传筛选和鉴定及综合防治等方面的主要研究进展,并提出了今后的研究方向和发展目标。     

昆虫组蛋白修饰的研究进展

组蛋白修饰作为表观遗传修饰的一种主要形式,对基因表达和表型调控具有重要作用。组蛋白修饰的N端尾区可通过乙酰化、甲基化、磷酸化等修饰来改变染色质的状态以及调控基因的表达。与脊椎动物相比,昆虫种类繁多,且有变态发育、表型复杂等特征,可以成为探索动物社会行为、发育调控和毒理作用等表观遗传基础的模型。本文总结了昆虫组蛋白修饰的主要类型(乙酰化和甲基化修饰)及修饰酶的研究进展,对染色质免疫共沉淀测序技术(chromatin immunoprecipitation followed by sequencing,ChIP-seq)、染色质转座酶可及性测序技术(assay for transposase-accessible chromatin with high-throughput sequencing,ATAC-seq)、转录组测序技术(RNA-seq)、组蛋白修饰酶功能验证以及Western blot、免疫细胞化学(immunocytochemistry,ICC)、免疫组织化学(immunohistochemistry,IHC)、酶联免疫吸附测定(enzyme linked immunosor...     

Major Changes in Fusarium spp. in Wheat in the Netherlands

The re-emergence of fusarium head blight throughout the world and especially in Western Europe prompted a survey of the situation in the Netherlands. To allow for a high throughput screening of large numbers of samples, a diagnostic PCR method was developed to detect the most common species of Fusarium occurring on wheat. Seven primer pairs were tested for their ability to identify isolates of Fusarium avenaceum, F. culmorum, F. graminearum, F. poae, F. proliferatum and Microdochium nivale var. majus and M. nivale var. nivale. Each primer pair only generated a PCR product with the corresponding Fusarium species and all PCR fragments had different molecular sizes. This allowed the generation of these amplicons using a mixture of all seven primer pairs. The robustness of this multiplex PCR encouraged us to screen a large series of isolates collected in 2000 and 2001. In both years 40 fields were sampled leading to a collection of 209 isolates from 2000 and 145 isolates from 2001. The results of the multiplex PCR demonstrated that F. graminearum was the most abundant species in the Fusarium complex on wheat in both years. This is in sharp contrast to reports from the 1980s and early 1990s, which found F. culmorum as the predominant species. Primers derived from the tri7 and tri13 genes, which are implicated in the acetylation and oxygenation of the C-4 atom of the backbone of the trichothecene molecule, were used to discriminate between deoxynivalenol and nivalenol (NIV) producers. The populations of F. culmorum and F. graminearum both showed a slight increase in NIV-producers in 2001.     

真菌甲硫氨酸生物合成途径研究进展

 甲硫氨酸是蛋白质的重要组分,同时还可通过生成S-腺苷甲硫氨酸（SAM）调控细胞内多种生理过程。本文根据酿酒酵母、粗糙脉孢菌和构巢曲霉3种模式真菌中甲硫氨酸生物合成的最新研究进展,勾画出真菌的甲硫氨酸合成途径,综述了该途径中关键酶的生物学功能,探讨了该途径的调控机制,为病原真菌甲硫氨酸合成的研究提供理论基础,同时为新杀菌剂的研发提供新思路。     

中国植物弹状病毒研究进展

弹状病毒含有单链负义RNA基因组,寄主范围比较广泛,能侵染无脊椎动物、脊椎动物以及植物等寄主,对人类的健康、农作物产量和自然生态系统造成严重威胁。植物弹状病毒主要根据复制场所分为细胞质弹状病毒属Cytorhabdovirus和细胞核弹状病毒属Nucleorhabdovirus,其基因组由单股负链RNA组成。此外,Dichorhavirus和Varicosavirus病毒属是两个新鉴定的植物弹状病毒属,其特征是具有二分体基因组。本文着重介绍危害我国农作物的几类植物弹状病毒,对它们的病理学、病害流行、基因组信息以及传播媒介进行概述,为中国植物弹状病毒病害的研究提供理论依据。     

Variability in initial spray deposit in apple trees in space and time

Variation in pesticide residues in space and time has not been investigated systematically in spite of the large variability found at single scales (e.g. between trees or orchards). Information on variability at different scales will support the development of sampling methods and more reliable prediction of residues. Experiments were conducted to quantify the spatiotemporal variability in initial spray deposit on apple leaves and fruit using a substitute tracer (zinc EDTA chelate). Five hierarchical spatial scales were defined as (1) between orchards, (2) between plots within an orchard, (3) between trees within a plot, (4) between zones within a tree and (5) between leaves/fruit within a zone. Similarly, two temporal scales were defined as (1) between applications within a single year and (2) between years. The initial zinc concentration was approximately log-normally distributed; the variability in initial deposit concentration was greater on leaves than on fruit. The average initial zinc deposition was significantly greater in the top and outside zones than in the middle zones within individual trees. The most important scale for driving residue variability is the within-zone unit-to-unit variation, contributing to 71 and 49% of the observed variability for leaf and fruit samples respectively. Variability at other scales was related to the variation in the tree architecture. The results indicated that stratified sampling on the basis of within-tree zone structures, with the effort focused on within-zone sampling, should be used for the determination of pesticide residues.