Effect of Rice Straw Mulching and Irrigation Regimes on Yield and Yield Attributes of Sunflower (Helianthus annuus L.) in Rice Fallow

A field experiment was conducted at Agricultural Research Institute, Professor Jayashankar Telangana State Agricultural University (PJTSAU), Hyderabad during rabi (December to March), 2021–22 to study the performance of zero tillage sunflower (Helianthus annuus L.) under different levels of rice straw mulching and irrigation regimes in rice fallows. The treatments were laid out in Factorial randomized block design (FRBD) in three replications with eight treatment combinations. Mulch treatments were two (M1-1.5 t ha-1 rice straw and M2-7.5 t ha-1 rice straw) and irrigation treatments were four (I1-IW/CPE=0.8, I2-IW/CPE=1.0, I3-IW/CPE=1.2 and I4-scheduling irrigation at critical stages) were allocated to different plots. The results revealed that capitulum diameter (14.3 cm), number of filled seeds per capitulum (1225), weight of filled seeds per capitulum (43.5 g), 100 seed weight (4.58 g) and seed yield (2216 kg ha-1) of sunflower was significantly higher under M2 (mulching with 7.5 t ha-1 rice straw) treatment than that of under M1 (mulching with 1.5 t ha-1 rice straw). The results also indicated that among irrigation treatments, the capitulum diameter (14.2 cm), No. of filled seeds per capitulum (1310), Weight of filled seeds per capitulum (45.2 g), 100 seed weight (4.62 g) and seed yield (2361 kg ha-1) of sunflower were significantly higher under I3-IW/CPE=1.2 treatment than that of under other irrigation treatments under study.