Effect of Different Ratios of Nitrate to Ammonium and Super Absorbent Polymer on the Yield of Medicinal Plant Dill (Anethum graveolens L.)

In order to investigate the effects of nitrate to ammonium ratios and different levels of a super absorbent on some traits of dill a factorial experiment was conducted in randomized complete block design during 2013 agronomic growing seasons in Jiroft region. Nitrogen fertilizer (150 kg ha-1) in five levels (0:100, 25:75, 50:50, 75:25, 100:0) and super absorbent in four levels (0, 10, 20, 30 g m-2) were studied. The results indicated that the consumption of various ratios of nitrate to ammonium and different levels of super absorbent had a significant effect on the dry matter, number of umbel per plant, number of umbellate per umbel, number of seed per umbellate, seed yield and percentage of essence. The highest seed yield was obtained from the simultaneous consumption of 25 percent nitrate, 75 percent ammonium and 20 g super absorbent. The lowest seed yield was also obtained from the application of 100 percent nitrate and no super absorbent. The highest essence percentage was obtained from the application of 100 percent nitrate and 30 g super absorbent and the lowest essence percent was obtained from the application of 100 percent ammonium and 10 g super absorbent. According to the results, in order to increase the seed yield, ammonium ratio should be increased and to increase the essence percentage nitrate ratio should be increased.