Control of Meloidogyne incognita in tomato by crambe extract using different application forms

ABSTRACT Crambe may be a viable alternative in the control of plant nematodes. The aim of the present study was to evaluate the best method for applying Crambe abyssinica extract to control Meloidogyne incognita. The first experiment was conducted in a (3x4+1) factorial design in a greenhouse, using three modes of extract application (leaf; soil; leaf + soil), in four times of application (before inoculation; during inoculation; after inoculation; and weekly until 45 days after inoculation), with an additional treatment (control). In the second experiment, factorial design was (3x2+1), with three application modes, as mentioned above, and two times of application (after inoculation and weekly). Application on the leaf after inoculation and weekly application on the soil reduced egg mass by 23.50% and 30.77%, respectively, compared to control. The reduction in the number of root-knots with weekly applications both on the soil and on the soil + leaf was 49.27%, compared to control. In the second experiment, less egg mass and total root-knots were verified with weekly applications. Second-stage juveniles (J2) and eggs per gram of root reduced after inoculation via soil + leaf and weekly inoculation via soil and via soil + leaf, showing values 55.24%, 61.57% and 60% lower than those of control, respectively. Crambe extract weekly applied on the soil showed promising for the management of M. incognita in tomato plants.【摘要】海甘蓝（Crambe）或许可作为植物线虫防控的可行替代方案。本研究旨在评估应用埃塞俄比亚海甘蓝（Crambe abyssinica）提取物防控南方根结线虫（Meloidogyne incognita）的最优方法。试验一采用温室（3×4+1）因子设计，设置3种提取物施用方式（叶面喷施、土壤灌施、叶面+土壤混施）、4个施药时期（接种前、接种时、接种后、接种后每周一次直至接种后45天），并增设空白对照处理。试验二采用（3×2+1）因子设计，施用方式同前，施药时期设为2种（接种后、每周一次）。与对照组相比，接种后叶面喷施及每周土壤灌施处理的卵块数量分别降低23.50%和30.77%；每周土壤灌施、土壤+叶面混施处理的根结数量较对照组降低49.27%。试验二中，每周施用处理的卵块数及总根结数均更低。经土壤+叶面混施于接种后施用、每周土壤灌施及每周土壤+叶面混施处理后，每克根组织内的二龄幼虫（J2）及虫卵数量均有所减少，分别较对照组降低55.24%、61.57%和60%。每周土壤灌施埃塞俄比亚海甘蓝提取物的方式，在番茄植株南方根结线虫防控中展现出良好应用前景。