Nutrient ratios and crop response in relation to soil reserve K in India. Indian Journal of Fertilizers.

Abstract

Field experiments were conducted to assess the soil test crop response (STCR) based fertilizer requirements forpearl millet–wheat sequence under integrated nutrient management (INM) under long term field experiment since2003 at IARI, New Delhi. The results indicated that the STCR based fertilizer with 10 tonnes FYM/ha recordedhighest mean grain (3.62 and 6.13 tonnes/ha) and stover/straw (7.0 and 8.01 tonnes/ha) yields of pearl millet (Pennisetumglaucum L. R. Br) and wheat (Triticum aestivum L.), which were 123.4 and 104.3 % higher in term of grain yield overcontrol, respectively. STCR based fertilizer with 5 tonnes FYM/ha, STCR based chemical fertilizer and RDF treatmentswere statistically at par with respect to yield of pearl millet and wheat. Higher system grain yield (9.74 tonnes/ha) ofpearl millet–wheat cropping system was recorded with STCR based integrated use of fertilizer with 10 tonnes FYM/ha. Nutrients uptake by pearl millet and wheat were significantly higher in STCR based fertilizer with 10 tonnesFYM/ha as compared to other treatments. Available N, P and K status in post-harvest soil was improved significantlywith 20 tonnes FYM/ha alone as compared to other treatments but statistically at par with STCR based fertilizer with10 tonnes FYM/ha. The long term study based on STCR clearly demonstrated that STCR based integrated use offertilizer for targeting yield can produce targeted yield of crops and save the fertilizer without impairing soil fertility