Nagachandrabose Seenivasan, Shanthi Mookiah, Shanmugam Sankaran Pagalahalli, Elaiyabharathi Thiyagarajan, Sharmila Radhakrishnan, Devrajan Kandasamy, Manickam Ravishankar, Srinivasan Ramasamy
Department of Nematology, Tamil Nadu Agricultural University, Coimbatore, India.
Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore, India.
Front Plant Sci. 2025 Aug 29;16:1623444. doi: 10.3389/fpls.2025.1623444. eCollection 2025.
Root-knot disease in tomato, caused by , presents a major challenge to global tomato production. This study explored a sustainable management approach by evaluating host-plant resistance through grafting combined with bio-inputs in farmers' fields with high natural infestations of .
The commercial F1 hybrid Shivam® tomato was grafted onto bacterial wilt-resistant eggplant rootstocks, EG 203 and TS 03. Two field experiments were conducted with six treatment groups to compare the performance of 'EG 203-tomato' and 'TS 03-tomato' grafts against the non-grafted hybrid tomato, both with and without bio-input applications. The bio-input protocol included soil application of neem cake (250 kg/ha) and soil and seedling drenching at nursery and transplant stages using biocontrol agents (Bacillus subtilis, , and , each at 5 g/L).
Results indicated that the 'EG 203-tomato' graft demonstrated strong resistance to M. incognita, while the 'TS 03-tomato' graft remained susceptible, akin to the non-grafted Shivam® hybrid. The EG 203-tomato graft treated with the bio-inputs achieved the highest suppression of , with reductions of 76.8-77.7% juvenile populations in the soil, 62.0-66.1% in female populations within roots, 73.6-77.3% in egg masses per female, and 38.1-40.0% in eggs per egg mass. This treatment also resulted in the lowest root gall index, measured at 2.0-2.1.
In both trial locations, 'EG 203-tomato' graft plants enriched with bio-inputs outperformed the non-grafted tomato in growth and yield metrics, achieving greater plant height (54.6-54.7 cm), leaf count (81.3-84.3 per plant), branch count (3.1-3.7) and fruit yield (10.8-11.5 kg/plant). These findings support the recommendation of EG 203-tomato grafts with bio-input management as an effective large-scale strategy for tomato growers combating infestations.
由南方根结线虫引起的番茄根结线虫病对全球番茄生产构成了重大挑战。本研究通过在南方根结线虫自然侵染严重的农田中，评估嫁接结合生物投入物的宿主植物抗性，探索了一种可持续的管理方法。
将商业F1杂交种Shivam®番茄嫁接到抗青枯病的茄子砧木EG 203和TS 03上。进行了两个田间试验，设置六个处理组，以比较“EG 203-番茄”和“TS 03-番茄”嫁接苗与未嫁接的杂交番茄在有无生物投入物施用情况下的表现。生物投入物方案包括施用印楝饼（250千克/公顷），以及在苗圃和移栽阶段使用生物防治剂（枯草芽孢杆菌、哈茨木霉和淡紫紫孢菌，各5克/升）对土壤和幼苗进行灌根。
结果表明，“EG 203-番茄”嫁接苗对南方根结线虫表现出较强抗性，而“TS 03-番茄”嫁接苗仍易感病，与未嫁接的Shivam®杂交种类似。采用生物投入物处理的EG 203-番茄嫁接苗对南方根结线虫的抑制效果最佳，土壤中幼虫数量减少76.8 - 77.7%，根内雌虫数量减少62.0 - 66.1%，每雌虫产卵块数减少73.6 - 77.3%，每卵块卵数减少38.1 - 40.0%。该处理的根瘤指数也最低，为2.0 - 2.1。
在两个试验地点，施用生物投入物的“EG 203-番茄”嫁接苗在生长和产量指标方面均优于未嫁接的番茄，株高更高（54.6 - 54.7厘米），叶片数更多（每株81.3 - 84.3片），分枝数更多（3.1 - 3.7个），果实产量更高（每株10.8 - 11.5千克）。这些结果支持将EG 203-番茄嫁接苗结合生物投入物管理作为番茄种植者对抗南方根结线虫侵染的有效大规模策略的建议。
