Effect of straw mulch and integrated nitrogen management on yield and quality of turmeric under North Indian plains

Abstract

The continuous application of nitrogen (N) through chemical source has shown deleterious effect on productivity of turmeric, whereas availability of organic source is very limited to meet the nitrogen requirement. Therefore it was considered worth to study the impact of integration of chemical and organic source of N on productivity of turmeric. A three-year field experiment was conducted at Punjab Agricultural University, Ludhiana, during 2011-12 to 2013-14 to study the response of turmeric to straw mulching and N applied through different combinations of organic manure (FYM) and N-fertilizer (urea). Application of paddy straw as mulch @ 6.25 t ha-1 significantly increased the plant height, number of tillers, mother, primary and secondary rhizomes, rhizome weight and yield of turmeric. The fresh rhizome yield increased by 85.0 and 34.9% during 2011-12 and 2012-13, respectively, due to mulch application over no-mulch. A slight improvement was noticed in curcumin content, however, the difference between mulch and no-mulch treatments was non-significant. Application of 125 kg N/ ha through FYM alone, produced the highest rhizome yield during all study years (20.6, 22.36 and 23.17 t/ha during 2011-12, 2012-13 and 2013-14, respectively), which was, however, statistically at par with the application of two-third and half of organic manure along with one-third and half of N through urea, respectively. Nitrogen substitution through urea beyond 50% resulted into reduced growth and fresh rhizome yield. Hence, integration of 50% of N (62.5 kg/ha) through organic manure (FYM) and 50% of N through fertilizer urea enhanced the turmeric yield as compared to 100% N fertilizer alone. Quality parameter in terms of curcumin content did not show any significant differences with the different combinations of integrated nitrogen source.