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81.
The resistance genes Lr9, Lr24, Lr25, Lr29, Lr35 and Lr37, which were not previously utilised in Hungary, have been incorporated into four Martonvásár winter wheat cultivars using marker-assisted selection with PCR-based markers. In the course of a backcross programme, the genes were transferred into Martonvásár wheat varieties and various BC generations were produced. Work aimed at pyramiding resistance genes is currently underway in Martonvásár, and plants containing the gene combinations Lr9 + Lr24, Lr9 + Lr25 and Lr9 + Lr29 are now available. From the BC2F4 generation of the ‘Mv Emma’*3/’R.L.6010’ combination (‘R.L.6010’ is the donor of the Lr9 gene) 287 lines were tested for leaf rust resistance in an artificially inoculated nursery. A co-dominant primer combination was designed to identify both resistant and susceptible offsprings. The results of resistance tests and molecular marker detection agreed in most cases. Designated leaf rust resistance genes were identified with molecular markers in wheat varieties and breeding lines. The Lr26 and Lr34 resistance genes occur frequently in the Martonvásár gene pool, and the presence of the Lr37 gene has also been detected in a number of Hungarian genotypes.  相似文献   
82.
Ohne Zusammenfassung  相似文献   
83.
18 strains of the house fly (Musca domestica L.) were tested by topical application for resistance to cypermethrin, permethrin, lindane, trichlorfon and malathion; three of them were additionally tested to dimethoate, dichlorvos and bromophos. The strain WHO/IN served as control. No resistance against the two pyrethroids could be demonstrated in the most strains, some of them were more susceptible than the control flies. Only in one strain the resistance was almost 20-fold. All strains showed resistance to lindane, with R>100 in two, R between 2 and 20 in the other strains. The resistance level to trichlorfon and malathion was very high (R>500 to trichlorfon, R>80 to malathion). Also to dichlorvos (R ranged from 2- to 5-fold), bromophos (R ranged from 20- to 30-fold), and dimethoate (R ranged from 5- to 8-fold) the resistance level was increased.  相似文献   
84.
Journal of Plant Diseases and Protection - The pine wood nematode, Bursaphelenchus xylophilus, can cause pine wilt disease on susceptible conifer species, mainly Pinus spp., outside its natural...  相似文献   
85.
We aimed to study tree effects on the chemical properties of forest soils. We compared soil features of three types of forest ecosystems, each with four stands (replicates): beech forests (Fagus sylvatica), oak forests (dominated by Quercus pyrenaica) and pine plantations (Pinus sylvestris). Five samples from the top 10 cm of soil were taken per stand, from which pH, organic matter content (O.M.), total nitrogen (N) and available calcium (Ca2+), magnesium (Mg2+), potassium (K+) and sodium (Na+) were determined. Litter layer depth was measured at each soil sampling point. We also measured tree density and crown diameters at each stand. Our results indicated that soil samples from the four pine plantation stands were more similar while oak and beech stands were characterised by great variability in terms of soil properties and leaf litter depth. Although the identity of the dominant tree species significantly influenced several topsoil chemical properties (increase in pH and available cations in oak forests and higher organic matter and total nitrogen in beech and pine ecosystems), there were other important factors affecting soil features that may be taken under consideration. Differences between soil properties of the three types of forest ecosystems were mainly related to the characteristics of the litter layer and less related to the tree layer structure. Finally, the establishment of pine plantations in naturally deciduous tree areas made the topsoil features more homogeneous.  相似文献   
86.
1概述甘蔗糖厂和甜菜糖厂从提汁车间提出的混合汁要经过澄清和过滤才能进入蒸发浓缩结晶工段 ,绝大部分糖厂的泥汁过滤是靠压滤机或真空吸滤机的滤布完成 ,滤布使用一段时间后由于固体物质堵塞 ,必须用清水加以冲洗 ,排出的冲冼水称之谓洗滤布水。目前大多数糖厂的洗滤布水未经任何处理便排走 ,造成严重的环境污染 ,因为这种洗滤布水量大 ,按日榨3000吨甘蔗的糖厂每天用洗滤布水量达800—1000吨之多 ,且水中约SS含量高达0.3—1.0 % ,COD含量1000—5000mg/L,还含有0.1—0.5 %的糖份 ,排放后易发臭 …  相似文献   
87.
Plant pathogens have developed different strategies during their evolution to infect and colonize their hosts. In the same way, plants have evolved different mechanisms acting against potential pathogens trying to infect and colonize their tissues. Regulation of a wide variety of proteins is required in order to perceive the pathogen and to activate the plant defence mechanisms. The apoplast is the first compartment where these recognition phenomena occur in most plant–pathogen interactions, allowing the exchange of different molecules and facilitating inter‐ and intracellular communication in plant cells. Proteomic analysis of the apoplast in recent years has found the initial biochemical responses involved in pathogen recognition and early defence responses. However, this proteomic approach requires some specific experimental conditions to obtain an extract free of cytoplasmic proteins and nonprotein contaminants that affect the subsequent stages of separation and quantification. Obtaining the highest proportion of proteins from the apoplastic space in infected tissues requires different steps such as extraction of apoplastic washing fluids and preparation of total secreted proteins (protein precipitation, solubilization, separation and digestion). Protein identification using mass spectrometry techniques and bioinformatics tools identifying peptides for the extracellular exportation is required to confirm the apoplastic location. This review compiles the most commonly used techniques for proteomic studies, focusing on the early biochemical changes occurring in the apoplast of plants infected by a wide range of pathogens. The scope of this approach to discover the molecular mechanisms involved in the plant–pathogen interaction is discussed.  相似文献   
88.
利用程序设计语言VB结合地理信息系统组件MapX、地理信息系统平台MapInfo Pro、SqlServer数据库等软件环境和空间拓扑关系、缓冲区分析等GIS技术设计并实现了农村配电网线路管理系统.该系统能够实现地图管理、线路图的绘制、切改和删除、空间和属性信息双向查询和统计、线路图输出打印等功能.详细阐述了系统的总体架构、功能设计、数据库分析和设计、关键技术和系统实现等.该系统已在河北保定某县电力局投入使用,取得了较好的效果.  相似文献   
89.
为了解桑植县植烟土壤中微量有效态营养元素含量状况,共采集桑植县植烟土壤耕层109个土壤样品并进行了分析。结果表明:桑植县植烟土壤中微量有效态营养元素总体含量较高,但分布不均衡,各地区间差距较大,有效铁、有效锰、有效铜、有效锌、有效硼、有效钼、有效硫的含量均值分别为46.09、43.23、1.14、1.87、0.66、0.24、37.86 mg/kg,局部地区应重视补充锌、铜,桑植县优质烟叶生产应当采取控铁、锰、硫肥的措施。  相似文献   
90.
Abstract

In preliminary field tests in woodlands swamps of southern Morava, ?SSR, it was found that Abate 500E at the rate 0.1 g/m2 of water surfaces killed Aëdes vexans, A. cinereus and A. sticticus larvae 3 instar during 24 hours, but in other case at the rate 0.05 g/m2 of water surfaces killed not the A. vexans pupae.

In southern Morava, CSSR a new larvicide, Abate* was tested for Aëdes larvae and pupae control in the field. Abate (0,0,01,01 -tetramethyl 0,01 -thiodi-p-phenylene phosphorothioate) is an organophosphate insecticide that has been highly effective when tested against many different species of mosquito larvae. It is of very low toxicity to man and presents a minimum hazard in control. A well timed application of Abate will control the mosquito larva before it can develop into a pupa. Barnes and Webb (1968) applied one briquette of 0.58 g or 0.78 g/10 cu. ft. water in woodland pools, against Aëdes canadensis (Thio.). A. cantator (Coq.). A. vexans (Mg.) and Culex restuans Theo. Early spring treatment controlled all species as they normally appear in chronological sequence until early fall. One treatment of 6 pools gave excellent larval control throughout the 176-day test period; 23 pools were retreated on day 57, but this may have been unnecessary. No deleterious effects were noted on aquatic organisms. The US Department of Health and Welfare (1968) reports that 1% granules of Abate (0.002–0.06 lb/ac) satisfactorily kills A. vexans larvae. Lewis et al. (1965) applied 43% ec. and 1% granules of Abate (0.075 to 0.2 lb/ac; or 0.084 to 0.22 kg/ha) to log ponds. Both formulations gave excellent initial and residual (up to 18 days) control at dosages used. The e.c. seemed to act for a longer period. It was used for Culex peus Speiser, C. pipiens L., C. tarsalis (Coq.) and Culiseta larvae control.

In southern Morava Abate 500E, a 50% (W/v) emulsifiable concentrate containing 500 g a.i./l was tested in the woodland swamps – mosquito breeding places – against A. vexans, A. cinereus Mg. and A. sticticus (Mg.) instar larvae or A. vexans pupae.

In the first experiment 10g Abate 500E were used on 100 m2 of water surface, mixed with water at 1:100. The insecticide was applied on two sites and a third chosen as control. Larvae were counted from 250 ml samples from each site. Table 1 shows the average number of larvae from each site.  相似文献   
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