Effect of Azospirillum in increasing yield and nitrogen use efficiency of sweet potato cultivation in India

• Published in: Advances in horticultural science 2009-01, Vol.23 (4), p.254-258
• Main Authors: Byju, G., Ravindran, C.S.
• Format: Article
• Language: English
• Subjects: Azospirillum; Food crops; Nitrogen; Planting; Recommendations; Soil treatment; Sustainable agriculture; Sweet potatoes; Tobacco chewing; Tubers
• ISSN: 0394-6169; 1592-1573

Sweet potato {Ipomoea batatas (L.) Lam.) is an important crop for human consumption, as animal feed and as industrial raw material for the production of starch, sugar and alcohol. Since the nitrogen use efficiency is very low in soils where sweet potato is generally grown in India, field experiments were conducted to study the effect of an integrated use of inorganic fertilizers and farm yard manure along with and without the application of the nitrogen fixing biofertiliser, Azospirìllum brasilense. Treatments included full dose, 2/3 and 1/3 of the present N recommendation along with and without Azospirìllum applied either or both as vine dipping and/or as soil application. The results indicate that the present level of nitrogen application can be reduced to one-third if we integrate this level with dipping of sweet potato vine cuttings at 2 kg ha⁻¹ for 15 min before planting and soil application of Azospirìllum at 10 kg ha⁻¹ at the time of planting. The B: C ratio was highest in this treatment. Even though the cost of cultivation was slightly higher in this treatment, due to the significantly higher tuber yield obtained, the economic returns as well as B: C ratio was the highest. It can also be seen that application of Azospirìllum along with fertilizer nitrogen had a beneficial effect on the fertility status of the soil in terms of available phosphorus and potassium.