Management of phosphorus and potassium in bidi tobacco (Nicotiana tabacum L.) under rainfed conditions

Abstract

A field experiment was undertaken at Regional Agriculture Research Station, Nandyal, Andhra Pradesh for four consecutive seasons from 2015-16 to 2018-19 on Vertisols under rainfed condition to find out the economics and management of phosphorus and potassium in bidi tobacco (Nicotiana tabacum L.) for higher cured leaf yield and quality. The experiment was laid out in a randomized block design with 8 treatments and replicated thrice. The data pooled over four seasons revealed that significantly higher leaf length (42.8 cm) and leaf width (17.3 cm) was recorded with 100% RDF (110 kg N + 70 kg P2O5+ 50 kg K2O ha-1) every year. Significantly higher cured leaf yield (1551 kg ha-1) and net returns (Rs 63,375 ha-1) were recorded with application of 110 kg N + 70 kg P2O5+ 50 kg K2O ha-1every year and on par with 100% RDN (110 kg N ha-1) +PK (70 kg P2O5+ 50 kg K2O ha-1) once in two years (1408 kg ha-1and net returns of Rs 59,275 ha-1). Leaf chemical constituents namely nicotine, reducing sugars and chlorides did not differ significantly due to different treatments and were in permissible limit. Post harvest soil analysis indicated that soil available N, P2O5 and K2O differed significantly due to different treatments and maximum amounts of available N (158.9 kg ha-1), available P2O5 (56.3 kg ha-1) and available K2O (537.3 kg ha-1) were recorded under treatment T5, T3 and T5, respectively. Soil pH and EC values were not affected significantly with the various treatments.