Effect of native Trichoderma viride and Pseudomonas fluorescens on the development of Cuscuta campestris on chickpea, Cicer arietinum

Cuscuta campestris Yuncker is a serious parasite on several leguminous crops including chickpea in India. Chickpea is an important pulse crop in India and severe incidence of Cuscuta may result in yield loss of about 85.7%. Management of Cuscuta is very difficult because of their intricate relationship with the host, wide host range and lack of resistant genes in the host. Thus induced systemic resistance (ISR) by plant growth promoting microbes (microbial elicitors) may be an effective alternative method for the management of Cuscuta. In the current study, to induce systemic resistance, native isolates of Trichoderma viride Pers. and Pseudomonas fluorescens Flügge were used as seed treatments and foliar spray on chickpea and then infested with C. campestris. Salicylic acid and thiobenzamidazole (synthetic elicitors) were used as standard inducing agents for comparison. Results indicated that fresh seeds of C. campestris germinated rapidly even without scarification and that the germination was not influenced by the proximity of the seeds to the host. Seed treatment followed by foliar sprays with the bioagents and synthetic elicitors induced at 20 and 40 days after sowing (DAS) induced increased production of defense enzymes in chickpea (Cicer arietinum L.) and thus delayed the development (1.8-5 days) and flowering (2.4-4.2 days) of C. campestris. Treatment with both the elicitors also resulted in the enhanced activities of scavengers of enzymes related reactive oxygen species (ROS). Thus the above work would help in the integration of the application of bioagents for effective management of Cuscuta in chickpea.