Effect of Phosphorus in Conjoint with Organics and Bioinoculant on Growth, Yield and Quality Parameters of Blackgram in Typic Chromustert

Aims: Use of phosphorus fertilizer along with farmyard manure, vermicompost and phosphorus solubilizing bacteria (Bacillus megaterium) in black calcareous soil was conducted to assess the impact on the growth, yield and quality parameters of blackgram variety VBN 8 during the year 2022.

Study Design: Randomized Block Design (RBD) with twelve treatments and three replications.

Place and Duration of Study: Kalligudi block of Madurai district, representing the Southern part of Tamil Nadu during the summer season of 2022.

Methodology: Twelve treatments were followed with various combinations of organics viz, vermicompost and farmyard manure, bioinoculant, and inorganic chemical fertilizer at different ratios. The combinations are 100 per cent and 75 per cent of P2O5 on STCR (Soil Test Crop Response) basis mixed with farmyard manure (1:10 ratio) and vermicompost (1:5 ratio). The impact of different treatments were recorded on shoot length, root volume, SPAD value, Leaf Area Index, grain yield, protein, cystine, and methionine content.

Results: Among the treatments, application of 100% of P2O5 on Soil Test Crop Response (STCR) basis incubated for 30 days with vermicompost at 1:5 ratio + phosphorus solubilizing bacteria @ 2 kg ha-1 T11 has improved the black gram shoot length (27.6 cm), root volume (2.43 cm3), SPAD value (45.91), Leaf Area Index at 20 DAS (1.09) and 40 DAS (3.7), grain yield (936.1 kg ha-1) protein content (23.21%), cystine content (1.97%) and methionine content (2.29%).

Conclusion: The integration of vermicompost and bioinoculant along with phosphorus fertilizer in black calcareous soil has improved the blackgram yield by 35.8% over the use of recommended dose of fertilizer alone. This result highlights the need of integrated application of phosphorus fertilizer along with organics and phosphorus solubilizing bacteria in black calcareous soil for sustainable production of blackgram.