The effects of cover crops on the biology of the soybean cyst nematode (SCN; Heterodera glycines) are not well established. It is possible that cover crops may reduce SCN population densities by acting as trap crops. Cover crops with potential to serve as trap crops may stimulate hatching and/or attract hatched SCN juveniles and also may be penetrated by large numbers of nematodes that cannot feed. Experiments were conducted to determine whether root exudates (REs) and soil leachates (SLs) from various cover crop plants affected SCN hatching and chemotaxis and if there were significant differences in SCN juvenile root penetration among different cover crop plant types. In 14-day-long hatching experiments, there was greater SCN hatching in crimson clover (Trifolium incarnatum) REs and SLs than in REs and SLs from all other cover crop treatments in the experiments. No other cover crop REs and SLs significantly affected hatching. In chemotaxis experiments, SCN juveniles were attracted to REs and SLs from annual ryegrass (Lolium multiflorum) and cereal rye (Secale cereale) after 24 h. In greenhouse experiments, significantly more SCN juveniles penetrated the roots of single cultivars of crimson clover, mustard (Brassica juncea), and rapeseed (B. napus) than 11 other cover crop species/cultivars evaluated in the experiment over the course of 20 days. Few SCN juveniles penetrated the roots of annual ryegrass and cereal rye. The results suggest that crimson clover, grown as a cover crop, has the most potential to act as a trap crop for SCN. Cover crop plants may affect SCN biology in ways other than the mechanisms investigated in these experiments.

覆盖作物对大豆胞囊线虫（SCN；大豆胞囊线虫）生物学的影响尚未明确。覆盖作物有可能通过充当陷阱作物来降低 SCN 种群密度。有潜力充当诱捕作物的覆盖作物可能会刺激孵化和/或吸引孵化的 SCN 幼体，也可能被大量无法进食的线虫侵入。进行实验以确定不同覆盖作物植物的根系分泌物（RE）和土壤渗滤液（SL）是否影响SCN孵化和趋化性，以及不同覆盖作物植物类型之间SCN幼根渗透是否存在显着差异。在为期 14 天的孵化实验中，深红色三叶草（ Trifolium incarnatum ）RE 和 SL 中的 SCN 孵化率高于实验中所有其他覆盖作物处理的 RE 和 SL 中的 SCN 孵化率。没有其他覆盖作物 RE 和 SL 对孵化产生显着影响。在趋化性实验中，24 小时后，SCN 幼虫被一年生黑麦草 ( Lolium multiflorum ) 和谷物黑麦 ( Secale Greeke ) 的 RE 和 SL 所吸引。在温室实验中，在 20 天的实验过程中，与实验中评估的 11 种其他覆盖作物物种/品种相比，侵入深红三叶草、芥菜 ( Brassica juncea ) 和油菜籽 ( B. napus ) 单一品种根部的 SCN 幼虫数量显着增加。很少有 SCN 幼虫侵入一年生黑麦草和谷类黑麦的根部。结果表明，作为覆盖作物种植的深红三叶草最有可能成为 SCN 的诱捕作物。覆盖作物可能以这些实验中研究的机制以外的方式影响 SCN 生物学。