Arthur Aston L, Hoffmann Ary A, Umina Paul A
Department of Zoology, Bio21 Institute, The University of Melbourne, 30 Flemington Rd, Parkville, Victoria 3010, Australia.
Environ Entomol. 2013 Oct;42(5):998-1012. doi: 10.1603/EN13008.
Tolerance and compensatory ability after invertebrate damage are important components of plant defense and are affected by various endogenous and exogenous factors. Here, we examine the impact of feeding damage caused by different densities of the redlegged earth mite (Halotydeus destructor Tucker) on the performance and recovery of canola and wheat seedlings at different plant developmental stages, and when grown under three levels of moisture stress. Both canola and wheat were susceptible to feeding damage caused by H. destructor at early growth development stages (canola-cotyledon, first and second true leaf stage; wheat-GS10 and GS12), but tolerated damage at the later growth stages (canola-third true leaf stage; wheat-GS14). Wheat plants compensated completely for mite feeding damage, while canola plants showed partial compensation when feeding occurred at the cotyledon and first true leaf stages. Canola was susceptible to immediate feeding damage from H. destructor under all levels of moisture stress and did not compensate for this damage over time when grown in the unstressed and moderately stressed treatments. Under severe moisture stress conditions, plant performance traits and mite density often showed a nonlinear relationship, with growth initially increasing as mite density increased, but then decreasing markedly as densities exceeded 30 mites/100 cm(2). Wheat seedlings were susceptible to immediate feeding damage when grown in the unstressed and severe stress conditions, but were generally able to compensate for this damage regardless of moisture conditions. The implications of these results for the management of H. destructor are discussed.
无脊椎动物取食损伤后的耐受性和补偿能力是植物防御的重要组成部分，并且受到各种内源性和外源性因素的影响。在此，我们研究了不同密度的红腿土螨（Halotydeus destructor Tucker）造成的取食损伤对油菜和小麦幼苗在不同植物发育阶段以及在三种水分胁迫水平下生长时的性能和恢复的影响。油菜和小麦在早期生长发育阶段（油菜-子叶期、第一和第二片真叶期；小麦-GS10和GS12）都易受红腿土螨取食损伤的影响，但在后期生长阶段（油菜-第三片真叶期；小麦-GS14）能够耐受损伤。小麦植株能够完全补偿螨类取食损伤，而油菜植株在子叶期和第一片真叶期受到取食时表现出部分补偿。在所有水分胁迫水平下，油菜都易受红腿土螨立即取食损伤的影响，并且在非胁迫和中度胁迫处理下生长时，随着时间推移无法补偿这种损伤。在严重水分胁迫条件下，植物性能性状和螨类密度通常呈现非线性关系，随着螨类密度增加，生长最初增加，但当密度超过30只螨/100 cm²时，生长明显下降。小麦幼苗在非胁迫和严重胁迫条件下生长时易受立即取食损伤的影响，但无论水分条件如何，通常都能够补偿这种损伤。讨论了这些结果对红腿土螨管理的意义。
