摘要：A field study was carried out during 2012-13 at Sindh Agriculture University, Tandojam, Pakistan, geographically latitude 25？N and longitude 68？E, to assess the effect of foliar applied urea on the growth and yield of sunflower. The experiment was laid out in a three-replicated Randomized Complete Block Design. Five treatments were tested against sunflower variety Hysun-33 which included: T1= Control (no urea), T2 = Recommended urea soil applied (130 kg·ha﹣1) at sowing stage, T3 = 1% urea at 35 days after sowing, T4 = 1% urea at 60 days after sowing and T5 = 1% urea at 85 days after sowing. The results revealed that growth and yield characters as well as oil yield of sunflower were significantly (P < 0.05) affected by foliar application of urea. The most effective treatment comprised of foliar application of urea (1%) after 35 days of sowing in addition to recommended soil applied urea (130 kg·ha﹣1) showed optimistic results with 89.61% seed germination, 179.65 cm plant height, 5.39 cm stem girth, 22.43 cm head diameter, 2063.25 grains head﹣1, 68.51 g seed index/1000 seed weight, 2211.90 kg seed yield ha﹣1 and 1046.75 kg oil yield ha﹣1. The sunflower crop receiving foliar application of urea after 60 days or 85 days of sowing in addition to recommended soil applied urea ranked 2nd and 3rd; and sunflower plantation given no foliar urea and grown only on recommended soil applied urea (130 kg·ha﹣1) ranked 4th with 1907.96 kg·ha﹣1 seed yield and 841.91 kg·ha﹣1 oil yield. However, sunflower plantation neither given foliar application of urea nor supplied with soil applied urea (control) ranked least for all the growth and yield parameters and oil yield. Hence, it is suggested for the farmers that in addition to 130 kg·ha﹣1 soil applied urea, foliar application of urea (1%) after 35 days of sowing may be ensured for maximization of seed and oil yields in sunflower. The results further showed that in most cases, the crop receiving foliar application of urea after 60 and 85 days of sowing showed similarity (P > 0.05); but differences were significant (P < 0.05) when compared with foliar application after 35 days of sowing and rest of the treatments.
