万强加有机添加剂防治番茄肾形肾状线虫试验研究

万强加有机添加剂防治番茄肾形肾状线虫试验研究黎少梅，黄长安（华南农业大学线虫研究室广州５１０６４２）肾形肾状线虫（Ｒｏｔｙｌｅｎｃｈｕｌｕｓｒｅｎｉ－ｆｏｒｍｉｓ）是仅次于根结线央的为害蔬菜的重要病原线虫，该线虫能侵染１００多种植物，其中许多是蔬菜和...     

根结线虫病的病原鉴定

根结线虫是植物寄生线虫中最重要的一类病原线虫,寄主范围广,分布普遍,根结线虫侵染植物(或品种),给农作物造成很大的经济损失。其为害特点是寄生专化性。因此,对根结线虫进行准确的鉴定是非常重要的。作者从广东省的广州市、坪石、新兴等13个县、市采集了31种作物根结线虫病的病     

用香茅叶提取液浸根防治蔬菜线虫病

经济验结果表明,甩香芽叶提取液能有效地防治分别为内、半内和外寄生的南方根结线虫、肾形线虫、芸苔矮化线虫对蔬菜作物的为害.     

肾形肾状线虫（Rotylenchulus reniformis）浙江杭州 群体形态学和分子特性及寄主范围

 肾形肾状线虫（Rotylenchulus reniformis）是一种重要的蔬菜线虫,寄主范围和分布很广。本文根据形态学特征和形态测量将来自浙江省杭州市蔬菜上的肾状线虫群体鉴定为肾形肾状线虫,为浙江省首次报道。该群体的形态学特征及形态测量值与模式标本基本吻合,个别形态测量值(比值)有变异。通过对该肾形肾状线虫群体的rDNA中ITS区和编码28S RNA基因中的D2D3区的PCR扩增和序列测定,明确二序列长度分别为808 bp和786 bp;序列分析发现该群体ITS序列与肾形肾状线虫种内一些两性生殖群体的亲缘关系较近,同源性高达99.5%～100%,而与一孤雌生殖群体同源性为92.4%;编码28S RNA基因中的D2D3区与已报道群体的同源性达到99.4%,相似度较高;本研究还发现杭州肾形肾状线虫群体的寄主涉及11个科16个属的果蔬。     

陕西省棉田主要线虫类群对棉花枯萎病发生影响的研究

 通过田间调查发现我省棉田的主要线虫类群有:植物外寄生线虫;小杆目线虫;具有吻针非植物寄生线虫等3种大类群。1985-1987年田间及温室盆栽试验,证明外寄生加洲螺旋线虫(Helicotylenchuscaliformicus)可加重棉花枯萎病菌(Fusarium oxyspotium f.vasinfectum)对棉花的为害程度;小杆目线虫和具有吻针的非植物寄生线虫同棉花枯萎病菌无复合侵染作用。田间防治试验表明,杀线剂通过降低田间寄生线虫的数量,减轻棉花枯萎病的为害,而对棉花枯萎病菌无抑制作用。     

海南省蔬菜根结线虫发生种类与分布

2014年-2018年, 对海南省蔬菜根结线虫病害进行了田间随机采样调查和病原种类分子鉴定?结果显示, 蔬菜根结线虫病在海南18市县均有发生, 且大部分旱田连作地块病株率达到80%以上?进一步对采集的295份根结线虫样本种类进行了分子鉴定, 共鉴定出象耳豆根结线虫?南方根结线虫和爪哇根结线虫3种病原种?其中, 象耳豆根结线虫单一检出率达到62.37%, 南方根结线虫单一检出率为23.39%, 爪哇根结线虫的检出率仅为5.76%, 象耳豆根结线虫和南方根结线虫复合侵染检出率为8.47%?除五指山市样本以外, 海南其余17市县样本均检测到象耳豆根结线虫侵染为害?本研究显示象耳豆根结线虫为海南省蔬菜上的优势病原根结线虫种类, 该结果对指导品种布局?制定根结线虫病害的防治策略具有重要意义?     

安徽省首次发现肾形肾状线虫危害瓜蒌

肾形肾状线虫Rotylenchulus reniformis Linford & Oliveira是作物根部半内寄生植物线虫, 被列为危害最严重的十大植物线虫之一。本文对安徽省新发生瓜蒌肾形线虫病的病原进行鉴定并对其生活史进行初步研究。利用形态学和分子生物学将病原线虫鉴定为肾形肾状线虫R.reniformis, 系统发育分析表明其属于A型。肾形肾状线虫在瓜蒌根部完成生活史需要24 d, 每条雌虫平均产卵64粒, 繁殖系数R=(11.12±0.62)。本文系首次报道肾形肾状线虫在安徽省发生危害, 瓜蒌为肾形肾状线虫的新寄主。本研究为进一步掌握肾形肾状线虫的分布区域及潜在寄主及综合防控提供了理论依据。     

利用索科线虫控制园林害虫的试验

我们在研究柞蚕寄生线虫时,共鉴定出索科线虫6种。这6种线虫除寄生于柞蚕外,还寄生于其他鳞翅目幼虫,并且寄生率相当高。索科线虫具有寿命长、生育期长、繁殖力强、侵染期长、寄生率高等特点。因此,考虑它能否在非柞蚕区作为一种寄生虫病,用来控制园林害虫。1975、1979和1982年,我们利用索科线虫中的秀丽复索线虫     

水稻孢囊线虫鉴定初报

寄生于水稻根部的孢囊线虫在我国尚未见报道。1982—1984年,我们在××县××乡的部分双季稻田(冬季种植马铃薯、蔬菜、甘薯)和小部分晚季稻田(春季种植花生、甘薯、冬季休间)范围内,四次发现水稻根部有孢囊线虫寄生而不侵染在这些田种植的冬、春作物。通过三次接种验证,该虫能侵     

3种杀线虫剂对香蕉土壤线虫群落结构的影响

比较不同杀线虫剂对植物寄生线虫的杀灭效果及其对土壤线虫群落的影响,对于杀线虫剂的选择具有指导意义。本研究比较了5亿活孢子/g淡紫拟青霉粉剂、1.8%阿维菌素乳油和10%噻唑膦颗粒剂3种杀线剂对植食性线虫的防治效果及其对土壤线虫群落结构的影响。结果表明:植物寄生线虫是连作蕉园优势营养类群。苗期时只有阿维菌素表现出对植食性线虫的杀灭效果;蕾期3种杀线虫剂均表现出显著的杀灭效果,植食性线虫的数量较CK分别减少49.3%、17.4%和84.2%;苗期时1.8%阿维菌素乳油表现出对螺旋线虫属和肾形线虫属的杀灭效果,10%噻唑膦颗粒剂处理中肾形属丰度较CK减少了20.3%;蕾期相比于CK,5亿活孢子/g淡紫拟青霉粉剂、1.8%阿维菌素乳油和10%噻唑膦颗粒剂处理中植物寄生线虫类群数均有所降低,各处理对优势属螺旋线虫属和肾形线虫属均有杀灭作用,减少的比例分别为48.2%、40.6%、95.7%和50.1%、7.1%、84.5%,差异显著。3种杀线剂处理均降低了土壤中的自由生活线虫种类和丰度。苗期1.8%阿维菌素乳油处理能显著增加食细菌线虫的数量,5亿活孢子/g淡紫拟青霉粉剂和10%噻唑膦颗粒剂处理的自由生活线虫成熟指数MI和多样性指数H′较CK显著降低;香蕉蕾期处理间MI没有显著差异,10%噻唑膦颗粒剂处理的植物寄生线虫成熟指数PPI较CK显著减少,均匀度指数J′显著高于其他处理。综上所述,10%噻唑膦颗粒剂的效果最好,持效期长,对植食性线虫有明显的杀灭效果,对土壤线虫类群多样性和线虫成熟指数无显著影响,适宜在香蕉种植园推广使用。     

当归麻口病的研究

 当归麻口病是我省当归产区区要病害之一,也是国内外未曾报道的一种新病害。1986、1987年调查研究表明,我省凡当归栽培区均有发生,田间发病率84.9%,病情指数56.4%,重病地高达100%。主要症状是归根表皮呈黄褐色纵裂,毛根增多并畸化,严重时皮层组织呈干烂,糠腐状。
从罹病归根皮层内外分离出线虫、真菌、细菌,分别进行人工接种健归苗并再分离发病归根,证实当归麻口病系线虫危害所致,其病原线虫为腐烂茎线虫(Ditylenchus destructor)。
经系统检测种苗不带线虫。病土和病残组织为初侵染源,腐烂茎线虫主要分布在0-10cm土层内,在当归整个生育期内线虫都可侵入,但以前期侵害为主,该线虫在当地一年可发生6-7代,以成虫在土壤和病残组织内越冬。     

Depth Distribution of Rotylenchulus reniformis Under Different Tillage and Crop Sequence Systems

ABSTRACT The population density of the reniform nematode, Rotylenchulus reniformis, was monitored at depths of 0 to 30, 30 to 60, 60 to 90, and 90 to 120 cm in a tillage and crop sequence trial in south Texas in 2000 and 2001. Main plots were subjected to three different tillage systems: conventional tillage (moldboard plowing and disking), ridge tillage, and no-tillage. Subplots were planted with three different crop sequences: spring cotton and fall corn every year; spring cotton and fall corn in one year, followed by corn for two years; and cotton followed by corn and then grain sorghum, one spring crop per year. The population density of R. reniformis on corn and grain sorghum was low throughout the soil profile. In plots planted with spring cotton and fall corn every year, fewer nematodes were found at depths of 60 to 120 cm in the no-tillage and ridge tillage systems than in the conventional tillage system. Population densities were lower at depths of 0 to 60 cm than at 60 to 120 cm. Soil moisture and cotton root length did not affect nematode population densities in the field. When soil was placed in pots and planted with cotton in the greenhouse, lower population densities developed in soil taken from depths of 0 to 60 cm than in soil from depths of 60 to 120 cm. Final nematode populations were similar in size in soil from the different tillage systems, but reproductive factors were higher in soil from plots with reduced-tillage systems than in soil from plots with conventional tillage. Reduced-tillage practices lowered the risk of increases in R. reniformis populations and reduced population densities following 2 years of non-hosts throughout soil depths, but population densities resurged to the same high levels as in soil planted with cotton every year during one season of cotton.     

Parasitism of the root-lesion nematode Pratylenchus thornei on chickpea

Pratylenchus thornei -chickpea interactions were investigated under controlled and fluctuating environmental conditions in the growth chamber, greenhouse and shadehouse. Under controlled conditions, P. thornei infected chickpea lines 12071/10054 and P2245 and cultivars Andoum 1, JG62 and UC27. Line P 2245 and cv. JG 62 were the most susceptible genotypes on the basis of root damage and nematode reproduction, but nematode infection did not significantly reduce root and shoot weights. Cultivars Andoum 1 and UC27 and line 12071/10054 showed the least root damage and nematode reproduction. Inoculation of cv. Andoum 1 with 2500, 5000 or 10000 nematodes per plant in pots did not affect shoot weight, regardless of the conditions of water stress of the plants. However, root weight was significantly reduced by nematode infection in plants grown under water stress and fluctuating temperature conditions in the greenhouse, but was not affected by any other treatment. The nematode reproduction index was not affected by soil water content under shadehouse conditions, but was greater on plants watered to soil water-holding capacity than in water-stressed plants under greenhouse conditions. For both environments, the nematode reproduction index decreased when inoculum density was greater than 5000 nematodes per plant.     

The effect of DD and dazomet treatments on nematode populations at various depths in the soil and on the transmission of soil-borne tobacco rattle virus to gladiolus

The relation between log dosage of DD injected at 15 cm depth or of dazomet applied to the soil surface (all in November 1971) and probit mortality ofRotylenchus and trichodorids in the top 20 cm of a field on sandy soil was found to be linear. Dosage increase efficiencies of both chemicals against both nematode species were medium to high. Superficial application of dazomet was very effective against the nematodes that would have survived if only a low dosage of DD had been injected at 15 cm depth. Injection of 40 ml or 80 ml DD per m² at 15 cm depth killed all nematodes between 20 cm and 60 cm deep. Gladiolus planted in the spring of 1972 grew better, flowered earlier and produced more weight of corms on treated than on untreated plots. The poor growth on the untreated plots cannot be ascribed to direct damage by nematodes or to the effect of TRV transmitted to the plants by the viruliferous trichodorids occurring in these plots in high densities. Symptoms of TRV infection in plants grown in 1973 from the corms harvested in the 1972 experimental field showed that only DD treatments had reduced the rate of TRV transmission considerably. However, even the highest dosages of DD had only reduced it from 26% (on untreated plots) to about 8%. Most probably, this residual TRV infection was due to transmission by trichodorids that had survived in soil layers below 60 cm depth. Therefore, soil treatment with nematicides, cannot prevent TRV transmission to gladiolus sufficiently where viruliferous trichodorids occur at great depths, as is the case in many sandy soils having a low water table.     

Host suitability of Vitis rootstocks to root‐knot nematodes (Meloidogyne spp.) and the dagger nematode Xiphinema index,and plant damage caused by infections

The host suitability of commercial Vitis rootstocks commonly used in Spain (161‐49C, 41B, 1103P, 110R, 140Ru and SO4) to root‐knot nematodes (Meloidogyne arenaria, M. incognita, M. javanica) and Xiphinema index, and damage caused by nematode infection were determined under controlled conditions. The three root‐knot nematodes reproduced with a rate higher than one in all rootstocks, indicating that they are suitable hosts for these nematodes. Growth of rootstocks infected with the root‐knot nematodes was less vigorous than that of nematode‐uninfected controls in the majority of the rootstocks studied. Root infection resulted in moderate to severe root galling in all rootstocks. The shoot and main stem diameters appeared to be the most sensitive variables of damage caused by infection by Meloidogyne spp., with reduction rates from 36% and 53% in 161‐49C to 57% and 66% in 140Ru, respectively. The shoot height was not significantly affected by the root‐knot nematodes and the root fresh weight generally increased as a consequence of intensive galling. The nematode X. index caused significant root damage with a reproduction factor higher than one in all rootstocks. However, reproduction factor was significantly influenced by the rootstock and significantly decreased by about 12‐fold (5·7 to 18·1‐fold) with the increase in inoculum density from 100 to 1000 nematodes per plant. The root dry weight was reduced by X. index infections, and was the plant growth variable most affected by the nematode infection in all rootstocks at both inoculum densities. Meloidogyne arenaria, M. incognita, M. javanica and X. index, prevalent in many world vineyards, are all shown to have a damaging effect on the six tested rootstocks.     

Differential effect of nematicide treatments on tuber yields in early- and late-maturing potato cultivars

A 3-year field study examined the effects of 1,3-dichloropropene or oxamyl on tuber yields in four early- and five late-maturing potato cultivars. The nematicide treatments increased total tuber yield by ≈ 12% for early-maturing cultivars, but by less than 2% for the late-maturing cultivars. The treatments reduced the numbers of root lesion nematodes (primarily Pratylenchus penetrans ), which were the dominant plant parasitic nematodes at the site. Covariance analysis indicated that treatment effects on total tuber yield were no longer significant after adjusting for root lesion nematodes in soil at harvest, confirming that these nematodes had a direct effect on the host. As expected, there were significant inverse relationships ( P  = 0·05) between total tuber yields and numbers of root lesion nematodes in soil and in roots. However, the application of nematicides in late-maturing cultivars was found to be of no practical value. Crop production systems designed to reduce or optimize pesticide applications can form one criterion in the development of more environmentally sensitive management strategies. The merit of utilizing chemicals for root lesion nematode control are considered with regard to cultivar maturity.     

湖北省蔬菜根结线虫病发生特点

调查了武汉、沙市、宜昌、恩施、孝感、黄岗、襄樊、荆门、十堰９地市郊的３４种蔬菜根结线虫病发生特点。结果表明,葫芦科、豆科和茄科蔬菜受害最重,发病级别达３～４级;红萝卜等１１种蔬菜受害较轻,病株率为２０％～５０％,病级１～２级;大蒜等１０种蔬菜未见发病。南方根结线虫（Ｍｅｌｏｉｄｏｇｙｎｅｉｎｃｏｇ－ｎｉｔａ）是引起我省蔬菜发病的优势虫种。５～３０ｃｍ的耕作层土壤中根结线虫群体数量较大,受害根常形成须根团,在５ｃｍ深度的土层中延伸达５０ｃｍ。     

红麻根结线虫生活习性及防治研究

研究表明,我国红麻上的根结线虫有南方根结线虫(Meloidogyne incognita)1号和2号小种,爪哇根结线虫(M.javanica)和花生根结线虫(M.arenaria)2号小种,南方根结线虫是优势种。它们都不为害棉花、花生、小麦、芝麻和苎麻,对高粱和玉米为害极轻。丝瓜、西瓜、番茄和空心莲子草为其共同寄主。南方根结线虫还侵染大豆、豇豆、苦瓜、菜瓜、南瓜、茄子、辣椒、烟草、黄麻、甘薯、黄瓜、白菜、莴苣、菜豆和扁豆等作物。红麻根结线虫的二龄幼虫主要分布在0～40cm 土层内,砂壤土中的线虫密度大于黄壤土。病原线虫以卵和二龄幼虫主要在病株残体中越冬。实行轮作、清除病残和药剂处理土壤是防治本病的有效措施。     

中华卵索线虫人工室内培养技术

为室内大量繁殖中华卵索线虫Ovomermis sinensis,采用个体由大到小的斜纹夜蛾Spodoptera litura、棉铃虫Helicoverpa armigera和黏虫Mythimna separata作为宿主,测定被中华卵索线虫寄生后3种宿主的体长和体重,研究宿主种类对中华卵索线虫有效率、雌雄比和体长的影响以及寄生强度对线虫雌雄比的影响。结果显示,被中华卵索线虫寄生后,斜纹夜蛾、棉铃虫和黏虫生长减缓。在相同感染比例下（除宿主与线虫比为1∶15外）,3种宿主的线虫有效率之间差异不显著。当寄生强度为5时,3种宿主体内脱出的中华卵索线虫均为雌线虫;当寄生强度从10增到40时,斜纹夜蛾、棉铃虫和黏虫所脱出的雌性比分别由100.0%、90.0%、83.9%降为0;相同寄生强度下,从斜纹夜蛾体内脱出的雌性比显著高于从棉铃虫与黏虫体内脱出的雌性比。斜纹夜蛾、棉铃虫和黏虫体内脱出雌线虫和雄线虫平均体长分别为14.8、13.8、12.8 cm和8.0、7.5和7.5 cm。当中华卵索线虫与宿主按照比例20∶1～25∶1侵染斜纹夜蛾、按照15∶1侵染棉铃虫和黏虫时,能获得线虫最适雌雄比（1∶1...