Williamson Valerie M, Thomas Varghese, Ferris Howard, Dubcovsky Jorge
Department of Plant Pathology; University of California, Davis, CA 95616.
Dept. of Entomology and Nematology; University of California, Davis, CA 95616.
Crop Sci. 2013 Jul-Aug;53(4):1412-1418. doi: 10.2135/cropsci2012.12.0681. Epub 2013 May 14.
Root knot nematodes (RKN; spp.) cause severe losses worldwide to a wide range of crops. Crop rotations with resistant hosts can be used to control losses, but the wide host range of RKN limits this option. In this study, we found that the wheat cultivar Lassik is resistant to several isolates of the RKN species and , including those that can reproduce on tomato with the resistance gene . Comparison of near-isogenic lines of wheat showed that the wheat resistance gene(s) is localized within a segment of the short arm of chromosome 2N from (Zhuk.) Chennav translocated into common wheat ( L.) chromosome arm 2AS and is associated with a highly significant decrease in RKN eggs in the roots. This RKN resistance gene has been assigned the name . While wheat itself is tolerant of RKN infection, a microplot experiment coupled with tomato bioassays showed less RKN root galling in the tomato samples grown in soil from the previous microplots including RKN resistant wheat varieties than in those including a susceptible wheat isogenic line. This result suggests that rotation with resistant wheat cultivars has the potential to be a valuable component of nematode management for crops that are highly susceptible to nematode damage and for which alternative strategies are limited.
根结线虫（RKN； 种）在全球范围内给多种作物造成了严重损失。与抗性寄主进行轮作可用于控制损失，但根结线虫广泛的寄主范围限制了这一选择。在本研究中，我们发现小麦品种拉西克对几种根结线虫物种的分离株具有抗性，包括那些能够利用番茄的抗性基因在番茄上繁殖的分离株。对小麦近等基因系的比较表明，小麦抗性基因定位于2N染色体短臂的一个区段内，该区段来自（朱克）切纳夫易位到普通小麦（ ）染色体臂2AS上，并且与根中根结线虫卵的显著减少有关。这个根结线虫抗性基因已被命名为 。虽然小麦本身能够耐受根结线虫感染，但一项小区试验结合番茄生物测定表明，与种植易感小麦近等基因系的小区相比，在包括抗根结线虫小麦品种的小区种植过的土壤中生长的番茄样品中，根结线虫引起的根瘿较少。这一结果表明，对于极易受到线虫损害且替代策略有限的作物，与抗根结线虫小麦品种轮作有可能成为线虫管理的一个重要组成部分。
