Mohamad Saad Maisarah, Rahaman Muhammad Matiar, Stout Michael J
Department of Entomology, Louisiana Agricultural Experimental Station, Louisiana State University Agricultural Center, Baton Rouge, LA.
Department of Agriculture, Pakutia College, Ghatail, Tangail, Bangladesh.
Environ Entomol. 2018 Apr 5;47(2):388-395. doi: 10.1093/ee/nvx199.
The resistance of commercial rice (Oryza sativa L.) varieties widely grown in Louisiana was assessed against the rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), the major insect pest of rice in the United States, in a 5-yr field study that included conventional inbred, herbicide-tolerant, and hybrid varieties. Resistance was evaluated by comparing densities of immature rice water weevils (larvae and pupae) in root-soil core samples taken at two time points after flooding. Randomized block experiments were conducted in two different locations to enable identification of potentially resistant varieties over diverse environments. There were small but significant differences in the resistance of commercial varieties over the 5-yr field study. The variety 'Jefferson' was found to support larval densities 6-70% lower than other varieties, while 'Jupiter' often supported higher larval densities. Greenhouse experiments evaluated adult preference for oviposition and survivorship of larvae on different varieties. Females exhibited limited ovipositional preference for varieties: numbers of weevil eggs per plant differed significantly among varieties in choice tests but not in no-choice tests, while first instar densities in both choice and no-choice tests showed no significant differences among varieties. Analysis of data from both choice and no-choice tests showed that numbers of late instars and pupae differed significantly among varieties, suggesting presence of antibiosis in some cultivars. Our results suggest that none of the varieties tested possess high levels of resistance to rice water weevil infestation, although 'Jupiter' appears to be more susceptible than other varieties and 'Jefferson' appears to be somewhat more resistant.
在一项为期5年的田间研究中，对路易斯安那州广泛种植的商用水稻（Oryza sativa L.）品种针对稻水象甲Lissorhoptrus oryzophilus Kuschel（鞘翅目：象甲科）进行了抗性评估，稻水象甲是美国水稻的主要害虫，该研究涵盖了常规自交系、耐除草剂和杂交品种。通过比较淹水后两个时间点采集的根土芯样中未成熟稻水象甲（幼虫和蛹）的密度来评估抗性。在两个不同地点进行了随机区组试验，以便在不同环境中鉴定出潜在的抗性品种。在为期5年的田间研究中，商用品种的抗性存在微小但显著的差异。发现品种“杰斐逊”所支持的幼虫密度比其他品种低6 - 70%，而“朱庇特”通常支持更高的幼虫密度。温室试验评估了成虫在不同品种上的产卵偏好和幼虫的存活率。雌性对品种的产卵偏好有限：在选择试验中，不同品种间每株植物上象甲卵的数量差异显著，但在无选择试验中无显著差异，而在选择和无选择试验中，一龄幼虫密度在不同品种间均无显著差异。对选择和无选择试验数据的分析表明，不同品种间老龄幼虫和蛹的数量差异显著，这表明一些品种存在抗生性。我们的结果表明，尽管“朱庇特”似乎比其他品种更易感，而“杰斐逊”似乎抗性稍强，但所测试的品种均不具有对稻水象甲侵害的高水平抗性。
