Effect of micronutrient and bioactive compounds fortified organic manure on the growth and yield of blackgram in coastal saline soil

Abstract

The micronutrients availability especially Zn and Fe is low in coastal saline soils due to soil characters such as poor texture, organic matter, leaching and chemical reaction involving precipitation and fixation at high pH and salinity. This results in greater yield reduction in such soil. To evaluate the influence of fortified organic manures on the growth and yield of blackgram in coastal saline soil, one field experiment was conducted in a farmer's field at Arunmozhidevan village, Parangipettai Block, of Tamil Nadu state during January-March 2018. The texture of the soil was sandy loam and taxonomically classified as Typic Ustifluvent. The soil analyzed pH 7.93, EC 2.03 dS/m and represented low status of organic carbon (0.44%). The soil had low alkaline KMnO4-N (120.21 kg/ha), Olsen-P (7.18 kg/ha) and NH4OAc-K (275.70 kg/ha). The following treatments, namely, T1-Control (recommended NPK), T2-NPK+ZnSO4 @ 25 kg/ha+FeSO4 @ 25 kg/ha, T3-NPK+100% Zn and Fe fortified organic manure @ 5 t/ha, T4-NPK+100% Zn and Fe+bio-active compounds fortified organic manure @ 5 t/ha, T5-NPK+75% Zn and Fe fortified organic manure @ 5 t/ha, T6-NPK+75% Zn and Fe+bio-active compounds fortified organic manure @ 5 t/ha, T7-NPK+50% Zn and Fe fortified organic manure @ 5 t/ha and T8-NPK+50% Zn and Fe+bio-active compounds fortified organic manure @ 5 t/ha were studied in RBD with three replications. Blackgram variety ADT 3 was cultivated. The results of the field experiment showed that all the growth characters like plant height, DMP, LAI, number of branches and yield components viz., number of pods per plant, number of flowers and 100-seed weight and seed and haulm yield were significantly influenced by the fortified manure application. Among the treatments, T6-NPK+75% Zn and Fe+bio-active compounds fortified organic manure @ 5 t/ha was superior in significantly increasing the growth and yield of blackgram. This treatment recorded a seed and haulm yield of 763 and 1314 kg/ha, respectively.