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1.
烟蚜茧蜂繁育及对烟蚜的防治效果探索   总被引:10,自引:2,他引:8  
653100云南省玉溪市红塔区许家湾路26号(农职院生活区)  相似文献   

2.
Tuber resistance to P. infestans was evaluated in the progeny of potato genotypes differing in levels of resistance and maturity. Two methods of tuber evaluation were used: testing whole tubers and testing tuber slices. In the progeny, some genotypes were superior in resistance to the more resistant parent. This superiority was never associated with early maturity. The results of both tuber-testing methods were positively correlated but the interaction genotypes X years was more pronounced in the reaction of tuber slices. It is concluded that: (1) transgression in tuber resistance may be obtained, (2) a high level of tuber resistance is difficult to combine with early maturity and (3) the expression of genes for specific resistance was more pronounced in testing tuber slices than in testing whole tubers.  相似文献   

3.
The tremendous seasonal variation of rainfall and the relative little dispose capacity of sewage are the main reason of the lack of water quantity and the contaminate of water quality in low water season in LIJIANG. Adjusting water quantity is an important measure to resolve the problem. So, the author does an investigation on water resource of LIJIANG, calculates upper-water supply and requires equation. As a result, in the condition of no water adjust, and if in the extraordinary year of the lack of water quantity, the water flow will fade in 2010, and the demand of water quantity of 30 m~3/s in the season of the lack of water will not be satisfied. Based on the actuality of water resource, the thesis introduces the project of mending water reservoir to LIJIANG,analyzes its feasibility in the respect of technique and financial condition,brings forward major problem of the project. The result proves the benefit of the project in the field of environment,economy society is very prominent, and the project is an engineering to realize water resource of LIJIANG reasonable utilize; for the reason to guarantee this project to bring into play its function,it is time to carry out integrate management to water resource and water environment in LIJIANG valley.  相似文献   

4.
利用不同药剂防治稻瘟病,结果表明:三环唑、多菌灵、稻温灵、春雷霉素第一次防治叶瘟效果均在70%以下,但与对照(清水)比较均达极显著水平.在破口初期及14天后连续2次药剂防治穗瘟,效果均达80%以上,其中:三环唑、多菌灵、稻瘟灵、春雷霉素4种药剂交替施用,防治效果最佳,其次为稻瘟灵,春雷霉素第三,第四为多菌灵;经方差分析,4种药剂防治效果与对照(清水)均达显著差异.经贵州省农药产品质量监督检验站对各药剂防治后稻米品质测试:多菌灵、稻瘟灵、春雷霉素3种药剂防治的稻米未检出三环唑含量,多菌灵、稻瘟灵、春雷霉素、三环唑4种药剂混合防治的稻米检出的三环唑含量为0.09 mg/kg,达绿色稻米卫生要求(三环唑≤1.0 mg/kg).  相似文献   

5.
S. M. Ali  B. Sharma  M. J. Ambrose 《Euphytica》1993,73(1-2):115-126
The economic importance and current progress made in studies of the host-parasite relationship and identification of sources of resistance and breeding strategies of some important biotic diseases of pea are reviewed in this paper. The root rot complex caused by Rhizoctonia solani, Fusarium solani, Aphanomyces euteiches, Pythium ultimum and Fusarium oxysporum f. sp. pisi, race 1 and 2 has been reported from all commercial pea growing areas of the world. Adequate sources of resistance have been identified and there has been impressive success in the control of the Fusarium wilt pathogen following the introduction of wilt-resistant cultivars. Leaf and stem diseases of pea caused by the Ascochyta complex, Peronospora viciae and Erysiphe pisi are prevalent in most temperate pea growing regions of the world. Several sources of resistance are available, some of which are surprisingly durable. The biochemical genetic parameters of phenolic content used for assaying resistance to Erysiphe pisi offers an alternative method of evaluating breeding material. Wild relatives of pea (Pisum fulvum and P. humile) are valuable additional sources of genetic variation and provide good sources of resistance to pests and diseases. In temperate rainfed pea growing areas of southern Australia, pea seed yield is more closely related to dry matter production than harvest index. Tall and leafy cultivars proved more productive than afila types.  相似文献   

6.
Density and the journey to work   总被引:2,自引:0,他引:2  
"This paper evaluates the influence of residential density on commuting behavior across U.S. cities while controlling for available opportunities, the technology of transportation infrastructure, and individual socio-economic and demographic characteristics. The measures of metropolitan and local density are addressed separately.... Regressions are conducted to predict commuting time, speed, and distance, by mode of travel on a cross-section of individuals nationally and city by city. The results indicate that residential density in the area around the tripmaker's home is an important factor: the higher the density the lower the speed and the shorter the distance.... The paper suggests a threshold density at which the decrease in distance is overtaken by the congestion effects resulting in a residential density between 7,500 and 10,000 persons per square mile (neither the highest nor lowest) with the shortest duration auto commutes."  相似文献   

7.
Summary Hybridization work was done between gloxinia and streptocarpus cultivars and species. No hybrid seeds were obtained. It is concluded that Sinningia speciosa cultivars and Streptocarpus sp. do not hybridize using conventional methods, in spite of positive reports in literature. The origin of these hybrids may probably be explained by the irregular occurrence of peloric flowers in streptocarpus, and zygomorphic flowers in gloxinia.  相似文献   

8.
牧草饲料是发展畜牧业的物质基础.种草养畜养禽已成为农业结构调整和农牧民致富奔小康的亮点.草是水土保持的先锋,锁住风沙的屏障;种草可改土肥田,改良盐碱滩涂,整治国土;还可美化环境、净化空气、减少公害;又可养蜂、养鱼等发展空中牧业和水体牧业,促进多种经营发展,增效增收.大力种植牧草饲料作物热潮正在进一步掀起.在繁多的牧草饲料作物种类品种中如何选择,到哪去买,是农户最关心的大问题.根据我们几十年从事牧草饲料作物引种栽培利用科研经验,结合生产实践和牧草饲料作物种子销售中存在的问题,提出看法,仅供农户参考.  相似文献   

9.
中间偃麦草抗小麦白粉病基因导入及其抗性评价   总被引:3,自引:0,他引:3  
为利用中间偃麦草对小麦白粉病的抗性,通过八倍体小偃麦TAI7045与普通小麦杂交、回交,育成一批兼抗我国黄淮麦区和西南麦区小麦白粉病、条锈病的新品系和新材料。抗性评价结果表明,无论苗期还是成株期,对小麦白粉病菌优势小种E09及强毒力小种E20、E21表现为免疫或高抗的有57份,占测试材料的67.9%;中抗的有10份,占11.9%,且对白粉病的抗性来自中间偃麦草。对随机选取的4份抗病品系及其与普通小麦的杂交F1进行了根尖细胞有丝分裂中期染色体计数和花粉母细胞减数分裂中期I(PMC MI)染色体构型分析,结果表明,它们的染色体数目均为2n=42,4个材料及其与中国春杂交F1的平均染色体配对构型分别为0.13Ⅰ+19.75Ⅱ+0.06Ⅲ和0.16Ⅰ+20.06Ⅱ+0.04Ⅲ,而且与中国春小麦的染色体配对构型无显著差异,说明它们的染色体组成与普通小麦基本一致,在遗传学和细胞学上已具有良好的稳定性。  相似文献   

10.
11.
李大平 《种子科技》2002,20(3):129-130
我国加入WTO后,对种业发展带来了有利因素,同时也带来了不利影响。我们要以积极态度,抓住机遇,迎接挑战。通过发展专业公司,提高种子质量,加快新品种选育,建立现代企业制度,规模经营和集约生产等措施,把中国种业推向国际种业大市场。  相似文献   

12.
Food shortage is currently a serious worldwide problem, and the fact that it will become an even greater problem in the coming decades underscores the necessity for more translational research in plant sciences that is directed towards crop breeding. Biotic stresses are important determinants of reduced crop production and, therefore, a better understanding of the resistance mechanisms utilized by plants to survive and remain productive following attacks by pathogens and pests is a major research goal of plant scientists and crop breeders. During the last two decades tremendous progress has been made in this field. Here we first summarize recent findings on how plants respond to their pathogens and pests and then we discuss resistance mechanisms in three categories based on differences in spectrum, durability and evolution. We also review different breeding strategies that have been adopted on the basis of these findings for improving resistance to pests and pathogens in crops and evaluate these strategies for their sustainability.  相似文献   

13.
引种是外来有害生物侵入的主要途径。历史上已经有了多起引种引起的危害事例。随着经济社会发展,植物种子(苗)入境数量倍数上升,检疫口岸面临压力越来越大,引种导致的生态风险也与日俱增。本文针对引种数量过大、业务交叉、信息不畅等现况,提出加强检疫监管力度,引导引种单位建立科学的引种制度、加快有害生物监测和风险分析的研究、完善隔离圃检疫工作等对策。  相似文献   

14.
以武运粳8号(粳稻)和扬稻6号(籼稻)为材,自抽穗后9 d至成熟期进行保持浅水层(WW)、土壤轻度落干(MD)和土壤水分严重亏缺(SD)3种处理。观察在不同土壤水分条件下灌浆期籽粒中乙烯和1-氨基环丙烷1-羧酸(ACC)浓度的变化及其与籽粒灌浆的关系,并使用化学调控物质进行验证。结果表明,MD显著提高籽粒灌浆速率和粒重,SD明显降低籽粒灌浆速率和粒重。籽粒中乙烯释放速率和ACC浓度在MD中降低,在SD中增加。籽粒乙烯释放速率及根系伤流液中ACC浓度与籽粒中ACC浓度呈极显著的正相关。籽粒灌浆速率与乙烯释放速率呈极显著负相关。在花后9~13 d喷施乙烯合成的抑制物质氨基-乙氧基乙烯基甘氨酸(AVG),明显降低籽粒中ACC的浓度和乙烯的释放速率,显著提高了籽粒灌浆速率和粒重以及籽粒中的蔗糖合成酶(SuSase)、ADP葡萄糖焦磷酸化酶(AGPase)和可溶性淀粉合成酶(SSSase)活性;喷施乙烯释放的促进物质乙烯利,结果则相反。表明结实期土壤轻度落干或适度干旱处理可以抑制水稻体内乙烯的产生,促进籽粒灌浆。  相似文献   

15.
通过对科技创新和成果转化状况的分析,认为基层农业科技单位是中国农业科技创新和科技成果转化的重要力量;但基层农业科技单位面临规模小负担重,资金不足人才匮乏,竞争能力不强等诸多问题。面对这一现状,基层农业科技单位唯有积极探索机制改革,强化科技创新,加速成果转化才能得以生存、发展和壮大。  相似文献   

16.
小麦抗麦红吸浆虫基因标记的开发与验证   总被引:1,自引:0,他引:1  
麦红吸浆虫(SitodiplosismosellanaGéhin)严重影响小麦产量和品质,选育和使用抗虫品种是降低虫害损失最安全有效的途径,利用抗虫性连锁或功能标记对提高小麦抗虫分子育种效率具有重要意义。在前期从转录组数据中挖掘到抗虫性主效QTL (QSm.hbau-4A) 6个相关差异基因的基础上,依据这些基因序列中存在的InDel和SNP,分别开发了2个EST标记和6个KASP标记,并在抗虫性不同的一套重组近交系(RIL)和一套小麦品种中进行了标记的有效性验证。所开发的8个标记在抗、感虫小麦亲本间均表现出较好的多态性,在RIL株系中的检测有效率均达到90%左右;除E10-10外,这些标记在供试高抗(56.3%~86.7%)和高感(85.7%~100.0%)小麦品种中的检测有效率均较高,可用于小麦种质资源的抗虫性筛选。同时发现, 11个具备所有抗虫标记位点的抗虫小麦品种,多为审定时间较早或已停止使用的品种,这使得结合标记辅助选择等手段鉴定和创新小麦抗虫种质资源的工作日益紧迫。  相似文献   

17.
A method was developed to assess sunflower resistance to sclerotinia root infections in greenhouses. Some of the genotypes were also tested in the field to validate the greenhouse testing method. Efficiency of this method was also tested in a diallel cross. The susceptibility could be assessed by the final percentage of dead plants or by the time required to reach a given threshold of attack (threshold latency parameter). The correlation coefficients between susceptibility assessed in the field and with the greenhouse method were significant. The diallel cross analysis indicated that only additive effects are important. Correlation for susceptibility to sclerotinia wilt, between parental lines and the mean of their hybrids, was significant. It is concluded that breeding programmes for increase of resistance to sclerotinia root and basal stem attacks, using the described testing method, should be effective.  相似文献   

18.
Location specific adaptation option is required to minimize adverse impact of climate change on rice production. In the present investigation, we calibrated genotype coefficients of four cultivars in the CERES-Rice model for simulation of rice yield under elevated CO2 environment and evaluation of the cultivar adaptation in subtropical India. The four cultivars (IR 36, Swarna, Swarn sub1, and Badshabhog) were grown in open field and in Open Top Chamber (OTC) of ambient CO2 (≈390 ppm) and elevated CO2 environment (25% higher than the ambient) during wet season (June–November) of the years 2011 and 2012 at Kharagpur, India. The genotype coefficients; P1 (basic vegetative phase), P2R (photoperiod sensitivity) and P5 (grain filling phase) were higher, but G1 (potential spikelet number) was lower under the elevated CO2 environment as compared to their open field value in all the four cultivars. Use of the calibrated model of elevated CO2 environment simulated the changes in grain yield of −13%, −17%, −4%, and +7% for the cultivars IR 36, Swarna, Swarna sub1, and Badshabhog, respectively, with increasing CO2 level of 100 ppm and rising temperature of 1 °C as compared to the ambient CO2 level and temperature and they were comparable with observed yield changes from the OTC experiment. Potential impacts of climate change were simulated for climate change scenarios developed from HadCM3 global climate model under the Intergovernmental Panel on Climate Change Special Report on Emission Scenarios (A2 and B2) for the years 2020, 2050, and 2080. Use of the future climate data simulated a continuous decline in rice grain yield from present years to the years 2020, 2050 and 2080 for the cultivars IR 36 and Swarna in A2 as well as B2 scenario with rising temperature of ≥0.8 °C. Whereas, the cultivar Swarna sub1 was least affected and Badshabhog was favoured under elevated CO2 with rising temperature up to 2 °C in the sub-tropical climate of India.  相似文献   

19.
G. H. Kim    H. K. Yun    C. S. Choi    J. H. Park    Y. J. Jung    K. S. Park    F. Dane    K. K. Kang 《Plant Breeding》2008,127(4):418-423
Resistance to anthracnose or black spot ( Elsinoe ampelina ), a serious fungal pathogen in viticulture and table grape production, was investigated on 25 grape cultivars. Bioassays performed with culture filtrates produced by the pathogen revealed 14 resistant genotypes. In most plants resistance originated from Vitis labrucsa but also genotypes with V. rupestris and V. riparia  ×  V. rupestris background showed resistance. Genetic analysis was conducted in F1, S1 and BC1 plants developed from various cultivars. In total, 326 F1 plants were evaluated, 172 genotypes proofed to be resistant, whereas 154 were susceptible to anthracnose. A Mendelian segregation ratio of 1 : 1 (χ2 = 0.30–0.65) indicating that anthracnose resistance is controlled by a single dominant gene. To facilitate the use of marker-assisted selection in grape-breeding PCR-based markers were developed by random amplified polymorphic DNA and amplified fragment length polymorphism in bulk segregant analysis. Finally, OPB 151247 was developed as a sequence characterized amplified region marker being diagnostic for the locus of resistance to anthracnose in all resistant genotypes tested. Within the 25 grape cultivars OPB 151247 is diagnostic in the genetic background of both V. labrucsa and V. rupestris and V. riparia  ×  V. rupestris .  相似文献   

20.
Cotton is a crop of tropical and subtropical regions but the seed cotton yield is highly influenced by abiotic stresses like drought and heat. Response of cotton genome to abiotic stresses is highly complex and involve many genes. A comprehensive study, involving cotton genotypes developed through conventional and synthetic tetraploid method, was designed to (i) study the introgression of heat and water stress tolerance by using wild relatives (ii) evaluate genetic markers for marker assisted selection against water and heat stress. Two separate experiments for water and heat stress tolerance with a common control were established. Treatments in each experiment include a control and a stress treatment. Heat stress was applied by sowing crop two month earlier than the control treatment, whereas water stress was imposed by withholding alternate irrigation. Analyses of variance depicted highly significant (P ≤ 0.01) effect of genotypes and both stresses on boll retention, boll weight and seed cotton yield. Interaction of genotypes with stress in both experiments was also highly significant (P ≤ 0.01). Genotypes derived from interspecific crosses performed consistently in stress conditions compared to control which prove it a reliable method to introgress stress related genes from wild parents. Four genes reported for water stress tolerance and five genes reported for heat stress tolerance were evaluated by field results for efficient marker assisted selection (MAS). Results verified drought stress genes but heat stress genes could not explain genetic variability caused by heat stress. It is concluded from the results that separate genes may be responsible for heat stress tolerance for vegetative and reproductive stages, therefore, selection criteria should include both the traits.  相似文献   

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