Vol. 7, Issue 10 (2018)

Author(s):
Sheth SG, Desai KD, Patil SJ, Navya K and Desai GB

Abstract:
A field experiment was laid out at Regional Horticultural Research Station, Navsari Agricultural University, Navsari on sweet potato cv. Collection-71 (C-71) during Rabi 2015. The experiment comprises of four levels of different nutrient sources [T₁: RDF (75 : 50 : 75 NPK kg ha^-1 + 15 t FYM ha^-1); T₂: 50 % RDN + 50 % N from vermicompost along with RDF of P & K; T₃: 50 % RDN + 50 % N from FYM along with RDF of P & K; T₄: 50 % RDN + 50 % N from bio-compost along with RDF of P & K] and two levels of Bio-fertilizers [B₀:without bio-fertilizers and B₁:with bio-fertilizers (combination of Azospirillum, Phosphorus solubilising bacteria (PSB) and Potassium mobilizing bacteria (KMB) @ 5 lit ha^-1 each)] in FRBD statistical design having three replications. Application of integrated nutrient sources did not showed significant effect on vine length at 30 DATP but at the age of 60 DATP, 90 DATP and at harvest, maximum vine length of 78.98 cm, 120.17 cm and 175.87 cm, respectively was recorded in T₂ treatment. Similarly application of bio-fertilizers did not have any significant results on vine length at 30 DATP. However, treatment B₁ (with bio-fertilizers) found best over treatment B₀ (without bio-fertilizers) and recorded significantly the highest vine length of 76.83 cm at 60 DATP, 117.03 cm at 90 DATP and 170.98 cm at harvest. The highest number of leaves (138.80) per vine at harvest was recorded in T₂ treatment and application of bio-fertilizers (B₁) also produced higher number of leaves (133.06) per vine than B₀ treatment at same stage. Treatment T₂ recorded maximum tuber girth (15.94 cm), tuber length (24.34 cm), highest average tuber weight (129.30 g), maximum number of tuberous roots (5.10), the highest fresh weight of tubers (0.512 kg) per vine, highest total tuber yield (8.27 kg netplot^-1 and 34.47 t ha^-1) and the highest marketable tuber yield (7.84 kg netplot^-1 and 32.67 t ha^-1) with the highest harvest index of 43.52 per cent. Application of bio-fertilizers (B₁) recorded significantly the highest values of tuber girth (15.47 cm), tuber length (23.15 cm), average tuber weight (126.73 g), number of tuberous roots (4.81) per vine, fresh weight of tubers (0.495 kg) per vine, total tuber yield (7.89 kg plot^-1 and 32.88 t ha^-1), marketable tuber yield (7.45 kg plot^-1 and 31.04 t ha^-1) and highest harvest index (41.44%) over the treatment of without bio-fertilizers (B₀) application. Irrespective of different nutrient sources, the difference in starch, total sugar, dry matter and moisture content in tuber was found non-significant. The data pertaining to the soil physical (Bulk density) and chemical (O.C., N, P and K) properties after harvesting the crop as influenced by integrated nutrient management were found to be non-significant except soil organic carbon content which was significantly the highest (0.603 %) in T₂ treatment. The highest gross and net income was obtained in T₂B₁ treatment combination but the highest B:C ratio (2.72) was obtained in T₃B₁ treatment combination.