Nutrient management with organic, inorganic and biofertilizers for yield attributes of soursop (Annona muricata L.) 

Abstract

A field experiment was carried out to study the effect of organic, inorganic and biofertilizers in soursop (Annona muricata L.) at Department of Horticulture, Faculty of Agriculture, Annamalai University during 2017-2019. Two years old soursop plants were used for this study. The experiment was conducted in a Randomized Block Design with eight treatments in four replications. The treatments include chemical fertilizers (80:60:40 g of NPK; 60:45:30 g of NPK and 40:30:20 g of NPK), organic nutrients viz., vermicompost@ 500 g, Biofertilizers (Azospirillum and Phosphobacteria)@ 50 g were applied per plant in the respective treatments. Humic acid@ 0.2 % spray was applied through foliar means once in 3 months. Totally 4 sprays were given starting from 2 years after planting in the respective treatments. The results revealed that among the various treatments tried, application of 80:60:40 g NPK/plant + Biofertilizer (50 g/plant) + Vermicompost (1/2 kg/plant)+ HumicAcid (0.2 % spray) resulted in improving the yield atributes like minimum days taken for flowering, number of flowers per plant, minimum days taken for fruit set, number of fruits per plant, per cent fruit set (%), fruit length(cm), fruit width (cm), fruit weight (g). This was closely followed by the application of 60:45:30 g NPK/plant + Vermicompost (1/2 kg/plant)+ Biofertilizer (50 g/plant) + Humic Acid (0.2 % spray).