Effect of macronutrients, microbial consortium and biostimulants on growth and yield of African marigold (Tagetes serecta L.)

Abstract

The present study was undertaken to bring out the best combination of microbial consortium on effect of biostimulant for the growth and yield of African marigold (Tagetes erecta L.) hybrid L3. The experiment was conducted in open field condition in a randomized block design with 10 treatments combinations and replicated thrice at ICAR-KVK, Bagalkot during the year 2017. Application of bio-control agents viz., Trichoderma harzianum, Pseudomonas fluorescens, Bacillus subtilis were applied in different combinations through soil application (SA), seedling treatment (ST), and foliar spray/application (FA) and were evaluated for growth promotion and disease management in marigold. The bio-stimulant, vermiwash was applied as foliar spray at four intervals at 30, 45, 60 and 75 days after transplanting. Observations were recorded on marigold growth, flowering and yield parameters. The growth parameters viz., plant height, number of primary branches per plant, plant spread, number of leaves per plant were recorded highest in treatment T8 compared to other treatments. Days taken for first flowering, days taken for 50% flowering, flower diameter, individual flower weight, flowering duration, number of flowers per plant, flower yield per plant and flower yield per hectare were also recorded highest in treatment T8 which received combined soil application of 50% recommended dose of fertilizers (63:30:30 Kg NPK ha-1) + soil application of bioagents @ 3kg/acre followed by seedling dip and foliar spray of Trichoderma harzianum (10ml/litre) +Pseudomonas fluorescens (10ml/litre)+ Bacillus subtilis (10ml/litre) and vermiwash (0.5%) compared to control. The disease incidence (PDI) of leaf spot and flower blight was observed less in T8 whereas, leaf spot and flower blight was high in control. Hence, treatment T8 was best for growth, development and disease management through organic way in marigold.