RESPONSE OF SUNFLOWER (Helianthus annuus L.) TO VARYING PLANTING GEOMETRY AND FERTILIZER LEVELS UNDER DIFFERENT LAND CONFIGURATIONS

A field experiment entitled “Response of sunflower (Helianthus annuus L.) to varying planting geometry and fertilizer levels under different land configurations” was conducted during Kharif 2013 at College Farm, College of Agriculture, Rajendranagar, Acharya N. G. Ranga Agricultural University, Hyderabad Southern Telangana climatic Zone of Andhra Pradesh. The soil of experimental site was sandy clay with pH of 7.54, electrical conductivity 0.32 dSm -1 , low in organic carbon (0.36 %), low in available nitrogen (267 kg ha -1 ), phosphorus (31 kg ha -1 ) and high in potassium (352 kg ha -1 ). The experiment was laid out in split plot design consisting of twelve treatments (Four main and three sub treatments) and replicated thrice. M1Flat bed sowing at 60 cm x 30 cm, M2Ridge and furrow sowing at 60 cm x 30 cm, M3Flat bed with paired row sowing at 45 cm x 40 cm (90/40 cm) and M4Broad bed and furrow with paired row sowing at 45 cm x 40cm (90/40cm) were the main plot treatments and S175 % RDF, S2100 % RDF(60:60:30 N, P2O5 and K2O kg ha -1 ) and S3-125% RDF were the sub plot treatments. Sunflower hybrid (DRSH-1) was sown on 9 th July 2013 and harvested on 18 th October, 2013. The results revealed that the growth parameters, yield attributes, yield and quality parameters of sunflower were not significantly influenced by planting geometry and land configurations. Graded level of fertilizers had significantly influenced growth parameters, yield attributes and yield of sunflower. Among the fertilizer levels, 125 % RDF recorded significantly higher growth parameters, yield attributes, yield, quality parameters and nutrient uptake over 75 % RDF but 125% RDF was comparable with 100% RDF. Significantly higher plant height, leaf area index, dry matter accumulation, stem girth, SPAD chlorophyll meter readings, head diameter, number of filled seeds head -1 , seed yield plant -1 and lower number of unfilled seeds head -1 were recorded with 125 % RDF over 75 % RDF. However 125 % RDF was comparable with 100 % RDF. The interaction effect on yield attributes was found to be non significant. Thousand seed weight was not significantly influenced by different treatments and due to their interaction. Seed, stalk yield and harvest index did not vary significantly among different planting geometry and land configuration treatments. Among the fertilizer levels, application of 125% RDF registered significantly higher seed (2221 kg ha -1 ), stalk yield (3889 kg ha -1 ) and harvest index (36%) over 75% RDF but it was comparable with 100% RDF that recorded seed, stalk yield and harvest index of 2080, 3748 kg ha -1 and 36 % respectively. The interaction effect on yield and harvest index was found to be non significant. Quality parameters viz; oil and protein yield were not significantly influenced by different planting geometry and land configuration treatments. Among the graded level of fertilizers application of 125 % RDF recorded higher oil and protein yield over 75 % RDF and 125 % RDF was comparable with 100 % RDF. Further nutrient uptake (N, P and K) uptake was also higher with the same treatments. The interaction effect was found to be non significant on quality parameters and nutrient uptake. Post harvest soil properties (pH, Ec and OC) and available soil nutrient status did not vary significantly due to different planting geometry and fertilizer levels and interaction. Higher post harvest soil available nitrogen, phosphorus and potassium status was recorded with 125% RDF. While, the lowest values were with application of 75% RDF. Gross returns ( 79701 ha -1 ), net returns ( 56549 ha -1 ) and B: C ratio (2.8) were highest with flat bed and paired row sowing at 45 cm x 40 cm (90/40 cm) applied with 125% RDF. Planting geometry and land configurations could not exert significant influence on growth parameters (except dry matter accumulation in capitulum at harvest), yield attributes (except filled seeds head -1 and yield plant -1 ), yield, quality parameters and nutrient uptake of sunflower. Among the different fertilizer treatments 125% RDF recorded higher plant height, leaf area index, dry matter accumulation, stem girth, SPAD chlorophyll meter readings and stem girth over 75 % RDF but was comparable with 100 % RDF. Yield attributes viz., head diameter, number of filled seeds head -1 , seed yield plant -1 , yield (seed and stalk), quality parameters, nutrient content and nutrient uptake (NPK) were significantly higher with the application of 125% RDF but it is on par with 100% RDF. From the present investigation it can be concluded that flat bed and paired row sowing at 45 cm x 40 cm (90/40 cm) and application of 125% RDF to sunflower crop was ideal for realizing higher seed yield and economic returns.