Optimizing tillage and irrigation for sunflower cultivation in rice fallow alfisols of semiarid tropics

Abstract

Studies were conducted on sandy clay loam soil (Typic Haplustalf) to evaluate the effect of five different tillage practices versus four irrigation regimes, 60 mm irrigation at IW/CPE=0.6, 0.8, 1.0 and 1.2, and their interaction on soil physical changes and performance of sunflower (Helianthus annuus L.) under rice fallow condition. Tillage in general had more positive effect on seedling emergence, growth and yield of sunflower than zero tillage in puddle rice fallows. Deep primary tillage with tractor-drawn disc plow or MB plow produced significantly larger heads with higher test weight, however, secondary tillage with rotavator, either power-tiller-or tractor-drawn, made finer tilth and recorded significantly higher seedling emergence (80.7%). Tillage with tractor-drawn disc plow + rotavator (deep-fine tillage) gave significantly higher mean seed yield (1311 kg ha -1 ) over tractor-drawn MB plow + tractor-drawn cultivator -deep tillage (1172 kg ha -1 ), ox-drawn desi plow + power-tiller-operated rotavator -shallow fine tillage (1054 kg ha -1 ) and ox-drawn desi plow + ox-drawn cultivator -shallow tillage (931 kg ha -1 ). The irrigation regime at IW/ CPE=1.2 recorded higher seed yield than IW/CPE=0.6, 0.8 and 1.0. Water use (ETa) by sunflower increased with increase in intensity of tillage and irrigation. WUE was higher in deep tillage practices and in irrigation regime of IW/ CPE=0.8. Deep tillage, besides saving 18% of irrigation water, resulted in about 24% higher sunflower seed yield compared with shallow tillage. Interaction effects revealed that significantly higher sunflower growth and yields (both seed and oil) was realized when tillage was done with tractor-drawn disc plow + rotovator coupled with scheduling irrigations at IW/CPE=1.0 or 1.2. Tillage with two passages of country plow + once with power-tiller-operated rotavator and scheduling irrigation at IW/CPE=1.2 produced significantly superior yields of sunflower than farmers' practice.

Irrigation Water, Deep Tillage and Gypsum Application Influences Soil Moisture regime, WUE and Sunflower Yield in Coastal Saline Soil of West Bengal

“…Similar findings were reported elsewhere (Ramamoorthy et al, 2009). Higher WUE with deep tillage at less frequently irrigated plots was attributed due to improved soil water retention making moisture available to sunflower throughout its growth stages (Gurumurthy et al, 2008;Salih et al, 1998). Improvements of WUE due to addition of sulfur through gypsum are also in consonance with the findings of Patel et al, (2008).…”

“…Similarly, moisture content during later crop growth stage was found to be more depleted in lesser irrigated plot (IW/CPE 0.50 and 0.75) than frequently irrigated plots (IW/CPE 1.0). Gurumurthy et al, (2008) also noticed higher moisture regime in soil at irrigation IW/CPE of 1.2 compared with IW/CPE of 0.8 and 0.6. Depletion of the soil moisture, at maturity, in less frequently irrigated plots is quite expected because of higher evapotranspiration demand than moisture available in soil.…”

“…Researchers found significantly higher WUE at deficit irrigation than that at fully irrigated plot (Flenet et al, 1996;Karam et al, 2007). Lower WUE associated with higher no of irrigation might be due to greater expense of water with comparatively less seed yield (Arora et al, 2011;Bharati et al, 2007;Gurumurthy et al, 2008;Reddy et al, 2008;Charanjit et al, 1998). Higher WUE in less frequently irrigated plots implied that the seed yield was disproportionate towards water used by the crop.…”

RESPONSE OF MAIZE (Zea mays L.) TO DIFFERENT TILLAGE REGIMES AND NITROGEN TIMINGS UNDER SEMI-ARID IRRIGATED CONDITIONS

“…Similarly, heavier and healthier grains was observed in chisel ploughed plots which may be attributed to well prepared seedbed which gave better environment to plant roots and ultimately resulted to healthy cobs and improved the 1000-grain weight as well as grain yield (Diaz-Zorita, 2000;Wasaya et al, 2011;Wasaya et al, 2017). Heavier thousand grain weight under chisel plough may be attributed to sufficient water availability in tilled plots which facilitated proper translocation of photosynthates resulting in good grain filling and ultimately produced healthy grains that resulted to higher 1000-grain weight (Gurumurthy et al, 2008). Similarly, higher grain yield with chisel plough is obtained as a result of more grains weight per cob and 1000-grain weight, which might be due to higher leaf area index (LAI) and crop growth rate (CGR) (Wasaya et al, 2017).…”