Indian Journal of Agronomy

A field experiment was conducted during rainy (kharif) season 2001 and 2002 at research farm of Banasthali (Rajasthan), to evaluate the interaction effect of four levels each of sulphur (0, 20, 40 and 60 kg/ha) and zinc (0, 2.5, 5.0 and 7.5 kg/ha) on groundnut (Arachis hypogaea L.). From the groundnut-growing fields of Tonk district, 125 surface (0–15 cm) soil samples were collected randomly for estimating availabe of S and Zn. Total S and Zn contents in the soil varied from 142.0 to 232.0 kg/ha and 4.0 to 26.0 mg/kg with mean values of 170.2 kg/ha and 21.3 mg/kg respectively. The availability of 0.15 per cent CaCO₃-extractable S and DTPA-extractable Zn was 6.1–17.8 kg/ha and 0.31–0.81 mg/kg respectively. Out of the soils studied, 59 per cent were found deficient in S and 31 per cent in Zn. Application of 40 kg S/ha and 5 kg Zn/ha significantly increased the pod yield of groundnut. The positive and significant interaction between S and Zn resulted in highest pod yield of groundnut (2,251 kg/ha) at 40 kg S and 5 kg Zn/ha. Maximum benefit: cost ratio was recorded with the application of 40 kg S and 2.5 kg Zn/ha. The use effeciency of S and Zn decreased with increase in the level of S and Zn, and maximum use efficiency was recorded at lower levels of S and Zn application.