Effect of Nutrient Management through Target Yield Approach on Uptake and Soil Microflora in Maize – Wheat/Chickpea Sequence Cropping System under Different Tillage Practices

A field trial was carried out during July month of kharif and October month of rabi seasons of 2013-14 and 2014-15 at Agricultural Research Station, Bheemarayanagudi to study the effect of nutrient management through target yield approach on uptake and soil microflora in maize – wheat/chickpea sequence cropping system under different tillage practices. The results indicated that the yield parameters of maize, wheat and chickpea at harvest did not influence due to tillage practices. All these yield parameters were relatively higher in zero tillage with mulch at 5 t ha-1 when compared to conventional tillage. Grain and stover yield of maize did not differ significantly due to different tillage management practices. But, zero tillage with mulch at 5 t ha-1 produced relatively higher yield (65.9 q ha-1) than the zero tillage (64.3 q ha-1) followed by conventional tillage (55.8 q ha-1). The higher organic carbon and soil microflora at different stages were noticed with zero tillage with mulch at 5 t ha-1. The higher available NPK and their uptake by maize crop were also recorded in zero tillage with mulch at 5 t ha-1 followed by zero tillage compared to conventional tillage and zero tillage. The lower available NPK and their uptake by maize crop were recorded in conventional tillage and RDF. Further, due to nutrient management through target yield approach, the yield parameters of maize were differed significantly. Target yield of 10 t ha-1 exhibited significantly higher yield attributes at harvest when compared to other treatments except the targeted yield of 8 t ha-1 and 150% RDF. The lowest values of these attributes were recorded in farmer’s practice of nutrient management followed by RDF. The grain yield and stover yield (69.9 q ha-1and 89.5 q ha-1, respectively) of maize was significantly higher with a targeted yield of 10 t ha-1 followed by targeted yield of 8 t ha-1 and 150% RDF. The lowest grain and stover yield (53.6 q ha-1 and 74.3 q ha-1, respectively) was recorded in farmers practice followed by RDF. Significantly higher soil microflora, available NPK and their uptake by the maize crop was noticed in target yield of 10 t ha-1 followed by targeted yield of 8 t ha-1 and 150% RDF as compared to other treatments. The lowest soil microflora, available nitrogen, phosphorus, and potassium (NPK) and their uptake by the maize was recorded in farmers practice followed by RDF. The same trend was followed statistically for organic carbon due to different treatments. Non significant differences for grain and stover yield of maize was recorded due to interaction of tillage and nutrient management practices. Similar trend was also followed due to interaction of tillage and nutrient management practices for succeeding wheat and chickpea. The yield and yield parameters of wheat and chickpea did not differ due to tillage practices and target yield approaches followed for maize. Maize equivalent yield of wheat and chickpea and system productivity were followed same trend as that of maize yield. Among different tillage practices, zero tillage and zero tillage with mulch at 5 t ha-1 were recorded maximum net returns and higher BC ratio. Similarly, among different nutrient management practices, the target yield of 10 t ha-1 followed by targeted yield of 8 t ha-1 was recorded maximum net returns and higher BC ratio as compare to other treatments.