Effect of Compost, Ascorbic Acid and Salicylic Acid Treatments on Growth, Yield and Oil Production of Fennel Plant

The present work was conducted during the two successive seasons of 2012/2013 and 2013/2014 to determine the effect of organic fertilization, foliar spray with ascorbic acid and salicylic acid as well as their interactions on growth, yield and oil production of fennel. Organic fertilizer was plant compost at 0, 8, 16 and 24 m³/fed. The plants were sprayed with ascorbic acid and salicylic acid each at 0, 50, 100 and 200 ppm. The revealed results indicated that utilizing organic manure increased herb dry weight/plant, number of umbels/plant, fruit yield/plant and yield/fed. Volatile oil % and volatile oil yield/plant and per fed. The highest values of such parameters were obtained by adding compost at the high level (24 m³/fed.). In most cases, spraying fennel plants with ascorbic acid or salicylic acid improved plant growth, fruit yield and oil production. Foliar spray with ascorbic acid at 100 ppm gave the maximum values of herb dry weight, fruit yield and volatile oil yield. The highest values of umbel number/plant were occurred by using ascorbic acid at 200 ppm in the first season and salicylic acid at 100 ppm in the second one. The application of ascorbic acid at 200 ppm registered the maximum values of volatile oil %. With regard to the interaction, the most of combined treatments showed a significant increase in all examined characters. The addition of compost at the high level (24 m³/fed.) plus 100 ppm ascorbic acid gave the highest values of herb dry weight, number of umbels/plant, fruit yield and volatile oil yield. While, the use of compost at the high level in combination with 200 ppm ascorbic acid recorded the maximum values of volatile oil %. From the obtained results, it could be recommended, to supply fennel plants with plant compost at 24 m³/fed in combination with foliar spray with ascorbic acid at 100 ppm to obtain better growth, high yield of fruit and volatile oil under this investigation conditions