Riga E, Porter L D, Mojtahedi H, Erickson D
Washington State University, IAREC, 24106 N. Bunn Road, Prosser 99350.
USDA-ARS, 24106 N. Bunn Rd., Prosser, WA.
Plant Dis. 2008 Jun;92(6):979. doi: 10.1094/PDIS-92-6-0979B.
In June 2006, stunted and chlorotic plants were observed in large patches in two 40.5-ha fields of dryland peas (Pisum sativum) in Latah County, Idaho, which resulted in 90 and 75% crop loss. In the same region, a 121.4-ha field of dryland lentils (Lens culinaris) also had plants showing poor growth, wilting, and yellowing in large patches, which resulted in 40% crop loss. Two species of lesion nematodes (Pratylenchus neglectus and P. thornei) and one species of pin nematode (Paratylenchus hamatus) were extracted from rhizosphere soil and the roots of symptomatic plants from these fields. In a subsequent survey of seven dryland pea fields, under cv. Columbian, in Latah and Nez Perce counties and one dryland pea field, under cv. Small Sieve, in Latah County, plant samples had means of 551 and 2,178 mixed species of lesion nematodes per gram of dry root, respectively. Plant samples from 12 lentil fields in Latah County, six planted with cv. Red Chief and six with cv. Pardina, had means of 279 and 987 mixed species of lesion nematodes per gram of dry root, respectively. Soil samples from the same fields had a mean of 628 and 671 pin nematodes, Paratylenchus hamatus, per 250 cm soil for Red Chief and Pardina, respectively. Lentils cv. Pardina and peas cv. Columbian were planted separately in six pots, five seeds per pot containing 250 g of infested soil brought from the field to the greenhouse. Fumigated sandy loam soil was used as control. These assays were repeated three times. In addition, peas and lentils were planted to pots infested singly with each of the three nematode species. For this assay, nematodes were extracted from field soil, surface sterilized, and used to infest 250 g of fumigated sandy loam soil at two nematodes per gram of soil. Six plants per nematode species and an uninoculated control were used in the greenhouse assays, which were repeated three times. Nematodes in all of the assays reduced plant growth in comparison with controls; an average of 50 to 70% reduction in plant height was noted. The lesion nematode populations increased in all pots. The greenhouse assays verified the negative impact of these nematodes on growth of dryland peas cvs. Columbian and Small Sieve and lentils cvs. Red Chief and Pardina. P. neglectus, P. thornei, and Paratylenchus spp. previously have been reported from the semi-arid Pacific Northwest (1). However, to our knowledge, this is the first report attributing plant growth and yield reduction of certain cultivars of lentils and peas to these two species of lesion nematodes and pin nematodes, identified to species level as Paratylenchus hamatus. Reference: (1) R. W. Smiley et al. J. Nematol. 36:54, 2004.
2006年6月，在爱达荷州拉塔县两块40.5公顷的旱地豌豆（Pisum sativum）田地里，大片植株出现发育不良和黄化现象，导致作物损失分别达90%和75%。在同一地区，一块121.4公顷的旱地小扁豆（Lens culinaris）田地里，也有大片植株生长不良、萎蔫和发黄，导致作物损失40%。从这些田地中有症状植株的根际土壤和根系中分离出两种短体线虫（Pratylenchus neglectus和P. thornei）和一种针线虫（Paratylenchus hamatus）。在随后对拉塔县和内兹珀斯县7块种植哥伦比亚品种的旱地豌豆田以及拉塔县1块种植小筛品种的旱地豌豆田进行的调查中，植物样本每克干根中混合短体线虫的平均数分别为551种和2178种。拉塔县12块小扁豆田的植物样本，其中6块种植红首领品种，6块种植帕尔迪纳品种，每克干根中混合短体线虫的平均数分别为279种和987种。来自相同田地的土壤样本中，红首领和帕尔迪纳品种每250立方厘米土壤中针线虫（Paratylenchus hamatus）的平均数分别为628条和671条。帕尔迪纳品种小扁豆和哥伦比亚品种豌豆分别种在6个花盆中，每个花盆播5粒种子，花盆中装有从田间带回温室的250克受侵染土壤。熏蒸过的沙壤土用作对照。这些试验重复进行了3次。此外，将豌豆和小扁豆分别种在单独受三种线虫中一种侵染的花盆中。对于该试验，线虫从田间土壤中分离出来，进行表面消毒，然后以每克土壤2条线虫的量用于侵染250克熏蒸过的沙壤土。温室试验中每种线虫设6株植株和一个未接种对照，试验重复进行3次。与对照相比，所有试验中的线虫均使植株生长受到抑制；植株高度平均降低50%至70%。所有花盆中的短体线虫数量均增加。温室试验证实了这些线虫对旱地豌豆哥伦比亚和小筛品种以及小扁豆红首领和帕尔迪纳品种生长的负面影响。此前在半干旱的太平洋西北地区已报道过P. neglectus、P. thornei和Paratylenchus spp. （1）。然而，据我们所知，这是首次报道将某些小扁豆和豌豆品种的植株生长和产量降低归因于这两种短体线虫以及鉴定到种水平为Paratylenchus hamatus的针线虫。参考文献：（1）R. W. Smiley等人，《线虫学杂志》36:54，2004年。
