School of Plant Protection, Yangzhou University, Yangzhou 225009, People's Republic of China.
J Econ Entomol. 2010 Aug;103(4):1166-71. doi: 10.1603/ec09265.
Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae) is a major pest in rice, Oryza sativa L. (Graminales: Poaceae), in Asia. The current study investigated the resistance of 17 rice varieties or lines to C. medinalis and behavioral responses of the insect to varieties of different corrected damage ratings (CDRs) and damaged leaves scales (DLSs). The results showed that most varieties (or lines) commonly cultured in rice production were susceptible (DLS 3 and 5) to damage caused by C. medinalis; Yangjing 9538, 91SP, and TN1 were the most susceptible (DLS 7 and 9). A significant positive correlation was observed between CDR and leaf width and chlorophyll content in rice leaves, whereas no significant correlations between resistance and plant height and leaf length were found. The number of eggs laid by C. medinalis adult females significantly increased with CDR. There was a significant difference in the number of eggs laid for varieties of different DLSs. The number laid on varieties of DLS 9 was 44.4, 134.5, and 466.7% greater than DLS 7, 5 and 3, respectively; the number laid on varieties of DLS 7 was 65.5% greater than DLS 5 and 300% greater than DLS 3; and the number laid on those of DLS 5 was 141.7% greater than DLS 3. Developmental duration (day) of larvae, the body length of fifth instar larvae and pupae weight also significantly increased with CDR. A significant difference of to excised leaves was also found among different DLSs with a higher proportion of both first and third instars settled on the leaves of high DLS. Dispersal experiments of larvae on excised leaves showed that the number of first instars that remained settled gradually increased with DLSs. These findings suggested that rice of higher DLS are more suitable for feeding and settling of larvae.
玉米螟（鳞翅目：草螟科），是亚洲水稻（禾本科：稻属）的主要害虫。本研究调查了 17 个水稻品种或品系对玉米螟的抗性，以及昆虫对不同校正损伤等级（CDR）和受损叶片鳞片（DLS）的品种的行为反应。结果表明，水稻生产中常用的大多数品种（或品系）对玉米螟造成的损伤均敏感（DLS3 和 5）；扬粳 9538、91SP 和 TN1 最敏感（DLS7 和 9）。CDR 与叶片宽度和叶绿素含量呈显著正相关，而与株高和叶片长度无显著相关性。玉米螟雌成虫产卵量与 CDR 呈显著正相关。不同 DLS 品种的产卵量存在显著差异。DLS9 品种上的产卵量比 DLS7、5 和 3 分别高出 44.4%、134.5%和 466.7%；DLS7 品种上的产卵量比 DLS5 和 3 分别高出 65.5%和 300%，比 DLS3 高出 141.7%；DLS5 品种上的产卵量比 DLS3 高出 141.7%。幼虫的发育持续时间（天）、五龄幼虫的体长和蛹重也随 CDR 的增加而显著增加。不同 DLS 之间的切叶也存在显著差异，较高的 DLS 叶片上有更多的一龄和三龄幼虫定居。幼虫在切叶上的扩散实验表明，留在定居的一龄幼虫数量随 DLS 的增加而逐渐增加。这些发现表明，DLS 较高的水稻更适合幼虫的取食和定居。
