Effect of phosphorus, sulphur and planting methods on growth parameters and total yield of groundnut (Arachis hypogaea L.) and sunflower (Helianthus annuus L.)

Results of field experiment conducted at I.A.R.I., New Delhi during Kharif seasons of 1999 and 2000 revealed that the growth parameters like leaf area index (LAI), net assmilation rate (NAR), total dry matter (TDM) accumulation and per plant productivity of groundnut were favoured by one month delay in planting of sunflower in groundnut-sunflower intecropping system in replacement series. The NAR of groundnut was decreased at early growth stage due to simultaneous sowing of both the crops, but at later stage, it was recovered and the TDM and productivity were compensated. Whereas, late planting resulted in low LAI, TDM and productivity of sunflower. Total productivity was not influenced by intercropping. In the intercropping system, LAI, TDM as well as pod/seed weight were increased due to application of phosphorus up to 40 and 80 kg P₂O₅ ha⁻¹ in groundnut and sunflower respectively, while application of sulphur up to 30 kg S ha⁻¹ increased these parameters in both the years. However, total productivity was significantly increased due to 40 kg P₂O₅ and 30 kg S ha⁻¹.