Zinc and Iron Nutrition to Increase the Productivity of Pearl Millet-Mustard Cropping System in Salt Affected Soils

Abstract

The abiotic stresses, such as soil salinity and sodicity are largely responsible for the low productivity of crops mainly due to low availability of micro-nutrients especially as zinc (Zn) and iron (Fe). Therefore, judicious management of plant nutrients in these soils is as important as their reclamation. A field experiment was conducted for 4 consecutive years, consisting of 12 treatments laid out in randomized block design to evaluate the effect of rate and methods of zinc and iron as single or combined soil as well as foliar application in pearl millet-mustard cropping system grown on salt affected soils. Soil application of Zn and Fe were applied at the time of sowing with FYM or without FYM (addition of FYM done only in pearl millet) and foliar application of respective nutrients were also applied at 30 and 45 days after sowing of crops. The results of experiment showed that, application of FYM 10 t ha-1 along with 5 kg Zn+10 kg Fe significantly (p=0.05) improved the yield parameters of pearl millet and mustard followed by 5 kg ha-1 Zn and 10 kg ha-1 Fe as soil application. The results also indicated that combined soil application of 5 kg Zn+10 kg Fe +10 t FYM increased the pearl millet grain yield (36.6 q ha-1) and mustard seed yield (22.7 q ha-1) by 57.1% and 42.8% higher over control, however, yield improvement was 35.6 and 20.7 % due to application of 5 kg Zn+10 kg Fe without FYM, respectively, in pearl millet and mustard over control. Ferrous-iron content in both crops proved to be a better index of Fe nutrition status compared to total plant Fe and DTPA- extractable soil Fe under salt affected soils. Salt affected soils are having vast potential to produce a significant amount of food grain by applying optimum dose of Zn, Fe and FYM in pearl millet and mustard. Combined foliar application of Zn and Fe also increased the yields of pearl millet and mustard grown in saline soils. Ferrous iron (Fe2+) is better indicator for iron nutrition in crops.