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通过2000—2009年对甘肃省古浪县阴湿山区小麦吸浆虫发生规律及温湿度条件综合分析,阴湿山区小麦吸浆虫成虫数量的多少、出现的迟早与6月上旬至7月上旬的气温和降雨量有密切关系。6月上旬至7月上旬气温越高(达到15℃以上)、6月中旬至7月中旬降雨量越多,吸浆虫成虫出现时间越早,虫量越大。根据2000—2009年调查资料和气象资料,总结出高海拔阴湿山区小麦吸浆虫盛发期10复网成虫数(Y)与6月上旬至7月上旬的平均气温(X1)和6月中旬至7月中旬的平均降雨量(X2)的关系,求得回归方程为:Y=33.6657-2.5560X1+0.3037X2。 相似文献
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为明确性信息素对油松毛虫Dendrolimus tabulaeformis成虫的监测量与不同危害程度林区失叶率及其幼虫虫口密度的关系,采用棋盘式五点取样法,将失叶率、幼虫虫口密度及成虫监测量两两进行模型拟合。结果显示,幼虫低虫口密度(y_1)、高虫口密度(y_2)与对应的成虫监测量(x_1)、(x_2)呈二次方曲线函数,方程分别为y_1=-0.060x_1~2+6.174x_1-85.753;y_2=0.076x_2~2-3.111x_2+109.844;在幼虫极高虫口密度(y_3)时,成虫监测量(x_3)呈线性递减,方程为y_3=-1.795x_3+214.060;幼虫虫口密度(y)、成虫监测量(x)随着失叶率(z)的增加而增高,但当失叶率超过74%时,幼虫虫口密度呈下降趋势,方程为y=-794.937z~2+1188.218z-308.626;当失叶率超过72%时,成虫监测量也出现下降,二者可以按照方程x=-189.035z~2+272.374z-53.474进行模拟。研究表明,幼虫虫口低密度、高密度与成虫监测量的相关性均显著,极高虫口密度时,成虫监测量呈下降趋势;幼虫虫口密度、成虫监测量均与失叶率呈二次方函数关系。 相似文献
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通过2002-2011年对贵州代表性烟区烟草蚜传病毒病(PVY、CMV)的系统调查与普查,分析了烟草蚜传病毒病发生程度与有翅蚜迁飞量及主要气象因子间的关系,初步了解了该病害的发生流行规律。并以有翅蚜迁飞量和关键气象指标为预报因子,应用DPS统计软件进行逐步回归分析,初步建立了烟草蚜传病毒病发生程度短期预测模型Y=44.168 7+1.106 9 X1-1.352 2 X4-0.403 9 X6-0.142 6 X11+0.023 5 X19-0.289 2 X20(其中,X1=移栽初期10d内日平均诱蚜量;X4=上年12月均温;X6=上年12月平均相对湿度;X11=2月降水量;X19=5月降水量;X20=5月雨日数),经显著性检验和预报验证,回归方程达极显著水平,回测准确率平均达89.04%,实报验证误差率为11.57%~13.88%,说明入选预报因子比较切合贵州实际,预测模型具有较大的实用价值。 相似文献
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通过抗生素处理去除丽蚜小蜂体内共生的沃尔巴克氏体,研究了沃尔巴克氏体对丽蚜小蜂产卵量、发育历期和成虫前(卵-成虫)死亡率的影响.结果发现:感染和去除沃尔巴克氏体的丽蚜小蜂产卵量(t=0.331,df=37,P=0.743)和发育历期(卵-蛹t=0.527,df=44,P=0.601;蛹-羽化t=0.640,af=42,P=0.526)不存在差异;而感染沃尔巴克氏体的丽蚜小蜂成虫前死亡率显著高于去除沃尔巴克氏体后的丽蚜小蜂(X2=17.934>X0.05,1=3.84).表明沃尔巴克氏体感染不影响丽蚜小蜂的产卵量和发育速度,感染和未感染沃尔巴克氏体的丽蚜小蜂生殖力的差别主要是由成虫前死亡率不同引起的. 相似文献
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本文对重要昆虫天敌捕虱管蓟马Aleurodothripsfasciapennis (Franklin)的产卵进行了观察。观察结果显示捕虱管蓟马雌成虫一生平均产卵 31± 9粒 ,平均产卵天数为 2 7~ 5天。用线性回归方程拟合产卵量与产卵期的线性方程为 :Y =1 5 2 6X - 8 931 ,相关系数R=0 95 5。 相似文献
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策勒戈壁盐生草种群特征的初步研究 总被引:3,自引:0,他引:3
通过对策勒戈壁分布的盐生草种群特征、水分利用效率的研究 ,得到策勒地区盐生草种群的平均盖度为2 .4 8% ,平均密度为 7.1株 /m2 ,平均株高为 6 .17cm ,生物积累量为 4 .6 2 g/m2 。种群分布格局类型呈典型成群分布 ,植株水分利用效率约为 0 .5 86kg/mm·hm2 ,平均根茎长度比为 2 .0 ,平均根茎重量比为 0 .0 5 6。盐生草株高与地上现存量之间的数量关系为 y =0 .0 6 77e0 .2 568x(0 7cm)。 相似文献
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为实现对田间土壤中禾谷镰孢Fusarium graminearum的定量检测,本研究构建了土壤含菌量与玉米苗枯病病情指数的回归模型。基于禾谷镰孢甾醇14α-去甲基化酶基因CYP51C序列,设计特异性引物HQ1-F/HQ1-R,利用引物建立实时荧光定量PCR(RT-q PCR)体系,选取4个玉米自交系品种进行室内苗枯病接种试验,调查其病情指数,利用RT-qPCR体系检测土壤禾谷镰孢含菌量,并对病情指数和土壤禾谷镰孢含菌量进行回归。结果表明,仅禾谷镰孢扩增出目的条带并且可从多种病原菌土壤中检测出。RT-qPCR的熔解曲线具有单一吸收峰,扩增曲线的循环阈值与模板浓度呈良好的线性关系,扩增效率为104.7%,标准曲线为y=-3.2137x+34.9560(R~2=0.9968),最低可检测到1 pg/μL的DNA。随着土壤禾谷镰孢接菌量的增加,单位土壤禾谷镰孢含菌量呈线性增加,即y=13.603x-85.370(R~2=0.9998)。4个玉米品种的病情指数与土壤禾谷镰孢含菌量的回归曲线分别为y=0.0789x+22.0590(R~2=0.7949)、y=0.0304x+7.8686(R~2=0.9579)、y=0.0458x+23.7540(R~2=0.5420)、y=0.0471x+32.0760(R~2=0.6753)。 相似文献
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The nature of a reductive system which actively degrades mexacarbate in the rat intestine and liver was investigated. The system is characterized by its stability against heat and protease treatments and its requirements for a flavin cofactor and an acidic pH for a maximum activity. As a result of purification and spectroscopic identification attempts the system responsible for the above reductive activity was identified to be flavoprotein. Under anerobic conditions such flavoproteinflavin cofactor systems degrade mexacarbate first to 4-N-desmethylmexacarbate and then to polar water-soluble metabolites. 相似文献
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A. D. Avgelis 《European journal of plant pathology / European Foundation for Plant Pathology》1986,92(4):147-152
Tomatoes grown in plastic houses in Crete have been inspected since 1980 for virus diseases. Plants with virus-like symptoms were checked by sap inoculation to test plants and the isolated viruses were identified by host reaction and serology. The most common viruses were, in order of frequency, tomato mosaic virus (ToMV), potato virus X, tomato bushy stunt virus (TBSV), potato virus Y and cucumber mosaic virus. The large use of ToMV-resistant cultivars reduces gradually the importance of ToMV while TBSV tends to become a serious problem of tomato in Crete.Samenvatting Van 1980–1984 werden op Kreta de in plasticfolie-kassen geteelde tomaten geïnventariseerd op de aanwezigheid van virussen. Verdachte plante werden door sapinoculatie op toetsplanten onderzocht. De daarbij geïsoleerde virussen werden daarna via de symptomen op de waardplanten en serologisch geïdentificeerd. In volgorde van belangrijkheid werden de volgende virussen het meest aangetroffen: tomatemozaïekvirus, aardappelvirus X, tomatedwerggroeivirus, aardappel Y virus en komkommermozaïekvirus, De laatste jaren is door de toenemende teelt van tomaterassen met resistentie tegen tomatemozaïekvirus het belang van dit virus sterk verminderd, terwijl het tomatedwerggroeivirus een steeds ernstiger probleem lijkt te worden. 相似文献
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A whitefly (Bemisia argentifolii) resistance crisis climaxed in 1995 in Arizona cotton and prompted the development of an integrated resistance management strategy adapted from a program implemented in Israel in 1987. The strategy incorporated two new major elements: once-per-year use of the insect growth regulators (IGRs) pyriproxyfen and buprofezin, and measures to delay use of pyrethroids for as long into the growing season as possible. A three-stage chemical use recommendation was formulated comprising IGRs (Stage I), other non-pyrethroid insecticides (Stage II), and synergized pyrethroid insecticides (Stage III). Results from use of the strategy in the 1996 season were very promising. Insecticide use for control of whiteflies was reduced substantially. State-wide monitoring of whitefly susceptibility revealed significant reductions in resistance to synergized pyrethroids as well as increased susceptibility to amitraz. Susceptibility of Lygus bugs to key insecticides changed correspondingly with increases and decreases in whitefly resistance from 1994 through 1996. ©1997 SCI 相似文献
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利用祁连山老虎沟地区海拔4200m气象观测站2010年的观测资料,采用FAO Penman-Monteith公式,再利用作物系数法,对高寒草甸生长季(5月22-9月22)的蒸散发量进行估算和分析。结果发现:研究期共有124天,蒸散发总量为238.3mm,日均为1.87mm·d-1。生长初期、生长中期、生长末期的蒸散发总量依次为22.6mm,179.1mm,36.6mm,依次占研究期总量的8.4%,75.2%,15.3%。5月下旬至6月中旬,日均蒸散发量以较低水平缓慢上升;6月下旬迅速增加;6月末至7月中旬猛然回落;7月中旬至8月末,日均蒸散发量迅速上升且维持在较高水平;此后直到9月22日,缓慢减少。5-9月月蒸散发总量依次为6.6mm,46.4mm,74.5mm,77.6mm,33.1mm。 相似文献
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A. D. Avgelis 《European journal of plant pathology / European Foundation for Plant Pathology》1987,93(4):153-158
During a survey of virus diseases affecting pepper grown in plastic houses in Crete, during 1984–1986, tomato mosaic virus (ToMV) and tobacco mosaic virus (TMV) were detected. The most common virus was TMV, being present in samples of alle pepper cultivars carrying the L1 resistance gene, while ToMV was isolated only from susceptible pepper cultivars. According to responses ofCapsicum spp. the isolates from 640 samples checked were classified into three pathotypes: P0, P1.2 and P1.2.3. Results of this study show that P1.2 represents at present the major threat to the Cretan pepper industry.Samenvatting Bij een in de jaren 1984–1986 gehouden inventarisatie van virusziekten in paprika in plastic-foliekassen op Kreta werd zowel het tabaksmozaïekvirus (TMV) als het tomatemozaïekvirus (ToMV) aangetoond. TMV kwam zeer algemeen voor: het werd aangetroffen in alle monsters van de paprikarassen met het resistentiegen L1. ToMV werd alleen geïsoleerd uit planten van vatbare paprikarassen. Volgens de waargenomen symptomen die de isolaten van 640 monsters opCapsicum spp. vertoonden, konden de isolaten in drie pathotypen, nl. P1, P1,2 en P1,2,3, worden geklassificeerd. Uit het onderzoek is gebleken dat P1,2 de belangrijkste bedreiging vormt voor de teelt van paprika op Kreta. 相似文献