Abstract

Restrictions about the use of chemicals have limited the availability of control measures against plant-parasitic nematodes. The search for more sustainable approaches has focused the attention on biological control agents, such as Trichoderma species. In recent years, there has been a growing interest in the use of biopolymers for a wide range of applications. These polysaccharide-based compounds may be 20 good carriers of microbial agents or act as barriers against pathogens or pests for their ability to form coating films. In this study, we evaluated the combination of a biopolymer obtained from the leguminous plant Ceratonia siliqua and T. harzianum M10, T. atroviride P1 or T. longibrachiatum MK1, as root protector or adjuvant agents, for the management of the root-knot nematode Meloidogyne incognita. Coating tomato roots with the carob galactomannan biopolymer followed by soil application of selected Trichoderma strains reduced the root galling index caused by M. incognita and soil nematode population in comparison to untreated control under greenhouse conditions. 25 Scanning electron microscopy revealed that coated tomato roots were embedded within a polymeric material. The sedimentation test showed that the addition of this biopolymer retarded the tendency of Trichoderma spores to settle in the bottom of aqueous suspension. In conclusion, beneficial fungi combined or formulated with a biopolymer could represent a promising strategy to increase their activity in plant protection and enhance their proliferation or distribution into rhizosphere.

摘要

化学品使用的限制限制了针对植物寄生线虫的控制措施的可用性。寻找更具可持续性的方法已将注意力集中在诸如木霉菌的生物防治剂上物种。近年来，人们越来越关注将生物聚合物用于广泛的应用领域。这些基于多糖的化合物可能是20种优良的微生物剂载体，或由于它们形成涂膜的能力而成为抵抗病原体或害虫的屏障。在这项研究中，我们评估了从豆科植物藜麦（Ceratonia siliqua）和哈茨木霉（T. harzianum）M10，阿托韦肽（T. atroviride）P1或长枝烟草（T. longibrachiatum）MK1提取的生物聚合物作为根保护剂或辅助剂的组合，以管理根结线虫。南方根结线虫。用角豆半乳甘露聚糖生物聚合物包被番茄根，然后在土壤中施用选定的木霉菌与未经处理的对照在温室条件下相比，菌株降低了由隐隐线虫和土壤线虫种群引起的根gall指数。25扫描电子显微镜显示，包被的番茄根部嵌入聚合物材料中。沉降试验表明，这种生物聚合物的加入抑制了木霉孢子在水悬浮液底部沉降的趋势。总之，与生物聚合物结合或配制的有益真菌可能代表增加其在植物保护中的活性并增强其在根际中的扩散或分布的有前途的策略。