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Search Results: 1 - 10 of 466119 matches for " <br>李茂业 "
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LI Mao,ZHANG Hong-ye,<br>,张洪
资源科学 , 2003,
Abstract: China's cultivated area has decreased steadily since 1957. In order to feed more and more people and to assure grain self-sufficiency in general, we have to improve yield of farm crops per hectare and keep certain area under cultivation. This paper has revealed the provincial difference, the quantity change of cultivated area and grain productivity change according to the data of long-series statistics of cultivated area, multiple cropping index, and grain yield during the past 50 years. This paper puts forward the conception of ratio of provincial's grain productivity to national average, and has quantitative analysis of the comparatively weightiness of cultivated land's grain productivity in every province, which is expected to provided scientific foundation for making-decision of protect cultivated land. There're obvious provincial difference in cultivated area and grain productivity change since the founding of New China. The regional difference of cultivated area change indicates higher productivity cultivated area decreases while lower productivity cultivated area increases. The cultivated area's grain productivity becomes small from south-east to north-west part in China. The highest cultivated area's grain productivity is located in the region of the middle and lower reaches of Yangtze River. Decrease of these provinces' cultivated land will exert greater influence. The driving forces for the decrease of cultivated land's grain productivity in south-east are lower comparative benefit, fewer cultivated land, denser population, and falling multiple cropping index.
资源科学 , 2003,
Abstract: 我国耕地面积自1957年以来持续减少。为了供养更多的人口、基本保证粮食自给,必须提高单位面积产量,并保持一定数量的耕地。根据50a来耕地面积、复种指数、粮食产量等统计资料,分析我国省际耕地面积和粮食生产力变化的差异,提出耕地粮食生产力相对指数的概念,定量分析各省耕地在全国粮食生产中的相对重要性,为耕地保护政策提供科学依据。建国以来我国的耕地和粮食产量变化具明显的省际差异,耕地变化的区域差异显示生产力较高的耕地在减少,生产力较低的耕地在增加。从东南向西北我国耕地粮食生产力逐渐下降,长江中下游地区耕地粮食生产力最高,这些省市耕地减少对粮食生产的影响更大,东南部耕地粮食生产力下降的主要是由于种粮的比较利益低下、耕地数量有限、人口稠密和复种指数下降等。
Screening of high virulent strain of Metarhizium spp. against the brown planthopper, Nilaparvata lugens

LI Mao-Ye,LIN Hua-Feng,LI Shi-Guang,ZHANG Song-Ying,<br>,林华峰,世广,张松影
菌物学报 , 2012,
Abstract: Nine strains of different species of Metarhizium,including strain of M.flavoviride(Mf82) newly isolated from Nilaparvata lugens(Stl),and eight M.anisopliae strains from lab collection,were tested against the adults of N.lugens.The chitinase activities of these strains were also assayed.The results showed that both the cumulative mortality(82.1%) and the chitinase activity(9.78U/mg) of strain Mf82 were the highest among all tested strains.Scanning electron microscope(SEM) observations showed the germinating conidia of the strain Mf82 penetrated the cuticle not only via the intersegmental membranes and folded regions,but also through the pronotum which contained a large quantity of chitin.The biological characteristics of these strains,including growth rate,sporulation,germination rate and timing of sporulation,were further investigated.The results showed Mf82 was the best strain having strong pathogenicity and exhibited a great potential for sustainable control of N.lugens.
Analyses of time-dose-mortality model of the emulsifiable formulation of Metarhizium flavoviride Mf82 against Nilaparvata lugens

LIN Hua-Feng,ZHANG Song-Ying,LI Mao-Ye,LI Shi-Guang,FENG Ming-Feng,<br>林华峰,张松影,,世广,冯明峰
菌物学报 , 2013,
Abstract: In order to effectively control Nilaparvata lugens, ten strains of entomogenous fungi including a new strain of Metarhizium flavoviride, Mf82, isolated from N. lugens and six strains of Beauveria bassiana and four different species of Metarhizium were bioassayed for its virulence against the adults of N. lugens. The results showed that cumulative mortality (81.7%) of strain Mf82 was the highest among all tested strains, and the median lethal time (LT50) value was 4.6d at a concentration of 1.0×108conidia/mL. Thus, an emulsifiable formulation of Mf82 was processed in the laboratory, and the bioassay of virulence of Mf82 against N. lugens was carried out. The results showed that the daily cumulative mortality of N.?lugens increased with the concentration of conidial suspension, and the highest concentration (1,048conidia/mm2) treatment caused 85.0% mortality. A time-dose-mortality model was used to analyze the bioassay data and the model fitted the data well, resulting in parameters for estimating the time and dose effects. The estimated LC50 values on day 7 and 9 post treatment were 2.1×103, 9.9×102conidia/mm2, respectively; while LC90 were 7.8×104, 3.7×104conidia/mm2, respectively. The LT50 of the emulsifiable formulation of M. flavoviride against the N. lugens differed at various logarithmic dose, and values of LT50 of tested agents were shortened with logarithmic dose. While logarithmic dose increased from 7.0 to 8.0, the LT50 values reduced from 8.9d to 5.7d. It is thus clear that the emulsifiable formulation of M. flavoviride has high virulence to N. lugens, and this new formulation could be used for biocontrol of N. lugens.
Gray Incidence Analysis between Cultivated Area and Grain Yield and its Affecting Factors of Henan Province

LI Mao,<br>
地理科学进展 , 2002,
Abstract: Cultivated area, population, and grain yield in Henan Province during the past 50 years are discussed in this paper based on statistical and survey data. It is found that (a) the general trend of net cultivated area loss started in 1955 which got continued; (b) the population in Henan Province will increase to 1×10 8 in 2005 and 1 06×10 8 in 2010; (c) total grain yield and grain yield per capital have increased in a fluctuant way since 1960; (d) grain yield per capital, effective irrigated area, and crop pattern have more effects on total grain yield based on gray incidence analysis and correlation analysis approach; and (e) multiple cropping index (MCI) of cultivated area in Henan Province is higher than national average standard, and the higher MCI, the more grain yield base on Regression analysis.
应用昆虫学报 , 2014,
Abstract: 【目的】明确q型烟粉虱对不同烟草品种的选择性及与叶背茸毛密度的相关性,为烟草抗虫品种的选育应用及对该虫的综合治理提供理论依据。【方法】在控制条件下,进行选择性试验、非选择性试验,观察发育历期和叶背茸毛数量。【结果】烟草品种对q型烟粉虱成虫选择性、产卵趋性及卵-成虫的发育历期影响显著,叶背茸毛密度与成虫趋性及产卵量之间具有显著相关性。在供试的8个烟草品种中,‘cf225’、‘cf226’叶背茸毛密度高,q型烟粉虱对它们的选择性强,表示这两个品种的烟草的抗虫性弱;‘云烟117’、‘k328(c8)’叶背茸毛密度低,q型烟粉虱对它们的选择性弱,表示这两个品种的烟草的抗虫性强。【结论】选育少毛的烟草品种,可以提高烟草对q型烟粉虱的抗性,本结果对烟草抗虫品种的选育有一定的参考价值。
应用昆虫学报 , 2011,
Abstract: (安徽农业大学植物保护学院合肥230036)摘要从田间褐飞虱nilaparvatalugens(stl)罹病虫体分离得到一株绿僵菌,以该菌为供试菌体,采用氯化苄法、ctab法以及裂解液法分别提取了该菌的基因组dna;以its1和its4为绿僵菌通用引物,对供试菌株的rdnaits序列进行pcr扩增、琼脂糖凝胶电泳检测和序列分析,并在核酸序列数据库中进行同源序列对比。实验结果表明裂解液法提取的该种绿僵菌的基因组dna纯度高且质量好,氯化苄法次之,ctab法不适合提取此菌的基因组dna;分子鉴定结果显示该菌为绿僵菌属黄绿绿僵菌(metarhiziumflavoviride)。明确侵染褐飞虱的绿僵菌种类,进而掌握其生物学特征和对寄主的致病性,对于利用其对褐飞虱进行生物防治具有重要的意义。关键词绿僵菌,dna提取,分子鉴定molecularbiologicalidentificationofentomogenousfungiisolatedfromthebrownplanthopperlinhuafeng**limaoyezhangsongyinglishiguangzhangchengqi(schoolofplantprotection,anhuiagriculturaluniversity,hefei230036,china)abstractthreedifferentmethodswereusedtoextractgenomicdnafromastrainofmetarhiziumspp.isolatedfromthesurfaceofinfectednilaparvatalugens(stl)collectedfromricefields;benzylchloride,ctabandcrackingsolution.thefungus’rdnaitssequencewasamplifiedwiththeprimersits1andits4,andtheamplifieditssequencedetectedbyagarosegelelectrophoresisandanalyzedingenebank.theresultsshowthatthecrackingsolutionmethodobtainedthehighestquantityofthepurestdna,thebenzylchloridemethodwasthenextbestandthectabmethodwasnotsuitable.homologoussequencecontrastconductedinthednasequencedatabaseidentifiedthefungusasmetarhiziumflavoviride.identifyingtheentomogenousfungithatinfectn.lugensisanimportantfirststepindeterminingtheircontrolpotentialwithrespecttothispest.keywordsmetarhiziumspp.,dnaextraction,molecularidentification
应用昆虫学报 , 2014,
Abstract: 【目的】明确烟草钾营养对q型烟粉虱q-biotypebemisiatabaci(gennadius)的寄主选择性、发育和存活的影响,旨在为通过调节寄主植物营养控制q型烟粉虱种群数量提供理论依据。【方法】水培法培养经k1(0mmol/l)、k2(3mmol/l)、k3(6mmol/l)、k4(9mmol/l)及k5(12mmol/l)5个不同钾浓度处理的烟草,研究q型烟粉虱在不同处理烟草上的寄主选择性、发育历期和存活率。【结果】q型烟粉虱在不同钾浓度处理烟草上的寄主选择性、发育历期和存活率均有显著差异,取食和产卵偏好性顺序为k2>k1>k3>k4>k5,卵到成虫羽化发育历期顺序为k5(22.54d)>k4(21.96d)>k1(20.92d)>k2(20.32d)>k3(20.23d),卵到成虫羽化存活率顺序为k3(88.72%)>k2(85.05%)>k1(82.03%)>k4(77.02%)>k5(69.92%)。【结论】可以通过调节钾营养来控制q型烟粉虱在烟草上的种群数量。
菌物学报 , 2012,
Abstract: 从田间褐飞虱Nilaparvatalugens(St?l)罹病虫体上新分离鉴定一株黄绿绿僵菌Mf82,将其与实验室保存的8株绿僵菌Metarhiziumspp.一起,分别测定其对褐飞虱成虫毒力和几丁质酶活力,并用扫描电镜观察侵入昆虫表皮的过程和体表的形态变化,进而分析侵入能力与几丁质酶的相关性。结果表明:菌株Mf82累计校正死亡率和几丁质酶活力均最高,为82.1%和9.78U/mg,与其他菌株差异显著。同时,扫描电镜照片显示Mf82分生孢子既可以由褐飞虱体壁节间膜和凹陷处侵入,还可以从含几丁质较多的胸部背板侵入。比较9株绿僵菌菌株菌落生长速度、产孢初始时间、产孢量和萌发率显示,Mf82菌株具有生长速度快、产孢初始时间短、萌发率高和产孢量大等优点,可见筛选的Mf82菌株致病力强,在褐飞虱的微生物防治方面将有良好的应用前景。
菌物学报 , 2013,
Abstract: 为了寻找褐飞虱Nilaparvatalugens生物防治的新途径,用新分离出的黄绿绿僵菌Metarhiziumflavoviride(Mf82)菌株与实验室保存的黄绿绿僵菌、金龟子绿僵菌和球孢白僵菌3种菌种9个菌株作对比,测定了它们对褐飞虱成虫的毒力。结果表明:Mf82菌株对褐飞虱成虫的毒力最高,以1.0×108个孢子/mL的孢子液喷雾接种到褐飞虱成虫体表上,累积死亡率高达81.7%,LT50为4.6d,致病效果显著高于其他受测菌株。在此基础上研制了黄绿绿僵菌悬乳剂,并研究了其对褐飞虱的致病力。结果表明:随着黄绿绿僵菌浓度的增加,褐飞虱的累计死亡率增加,在浓度为1,048个孢子/mm2时,累计死亡率达到85.0%。利用时间-剂量-死亡率模型对数据进行处理,所建模型均顺利通过Hosmer-Lemeshow拟合异质性检验,表明模型拟合良好,并由模型估计出了该剂型对褐飞虱的致死剂量与致死时间。在接种后第7天和第9天,LC50值分别为2.1×103、9.9×102个孢子/mm2,LC90分别为7.8×104、3.7×104个孢子/mm2。黄绿绿僵菌悬乳剂对褐飞虱的致死时间与对数剂量相关,供试菌剂LT50值随着对数剂量的增加而递减,对数剂量由7.0增加到8.0时,LT50由8.9d降为5.7d。可见该黄绿绿僵菌悬乳剂对褐飞虱具有较强的毒力,在褐飞虱生物防治中具有广阔的应用前景。
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