Response of rainfed sunflower (Helianthus annuus L.) to varying planting geometry and fertilizer levels under different land configurations in Vertisols

A field experiment was conducted for two consecutive rainy seasons during 2016 and 2017 at Regional Agricultural Research Station, Nandyal, Kurnool district of Andhra Pradesh under All India Coordinated Research Project on Sunflower to study the response of rainfed sunflower to varying planting geometry and fertilizer levels under different land configuration. The experiment was laid out in a split plot design with four main plot treatments viz., M1 - Flat bed sowing 60 cm x 30 cm, M2- Ridge and furrow sowing 60 cm x 30 cm, M3 - Flat bed with paired row sowing 45 cm x 30 cm (90/40 cm) and M4 - Broad bed and furrow with paired row sowing 45 cm x 30 cm and three sub-plot treatments viz., S1 - 75 % RDF, S2 - 100 % RDF (60:30:30 N, P2O5 and K2O kg/ha) and S3 - 125% RDF and replicated thrice. The results indicated that moisture use efficiency was found highest in broad bed and furrow paired row sowing (8.0 and 7.1 kg/ha-mm in 2016 and 2017, respectively) followed by ridges and furrowat 60 cm x 30 cm sowing (6.8 and 6.2 kg/ha-mm in 2016 and 2017, respectively). Highest seed yield (1632 kg/ha) was recorded with broad bed and furrow paired row 45 cm x 30 cm treatment followed by ridge and furrow 60 cm x 30 cm treatment (1398 kg/ha), which were superior to flat bed paired row 45 cm x 30 cm (1155 kg/ha). Broad bed and furrow paired row sowing at 45 cm x 30 cm recorded higher net returns (` 21450/-) and B: C ratio (1.82) followed by ridges and furrow sowing at 60 cm x 30 cm.