الفهرس | Only 14 pages are availabe for public view |
Abstract This study was carried out at Horticultural Research station El- Kanater El-Kaliobia Governorate, Egypt, during the two successive seasons of 2014 and 2015. The aim of this experiment was to investigate the effect of irrigation levels and foliar spray substances on vegetative growth, yield and its components, chemical and quality of corms and water use efficiency of taro plants. The experiment included 16 treatments (4 irrigation levels X 4 foliar spray substances ) arranged in a split plot design, with three replicates. The main plots were for irrigation levels and foliar spray substances were in the sub plots. The treatments were four levels of drip irrigation at 120,100, 80 and 60 % of the evapotranspiration (ETo) and four foliar application treatments which were check (water and a wetting agent), seaweed extract at 300 ppm, potassium silicate at 200 ppm and absissic acid at 30 ppm. The results could be summarized as follows: 1. Vegetative growth characters a. Effect of irrigation levels The irrigation with 120 % of the evapotranspiration caused a significant increase in all growth characteristics of taro plamt , expressed as plant height , number of leaves, leaf area,total chlorophyll and dry matter of leaves. b. Effect of foliar spray substances Application of seaweed extract or potassium silicate (K2 SiO3( led to a significant increase in vegetative growth of taro plants expressed as plant height, number of leaves, leaf area,total chlorophyll and dry matter of leaves. c. Effect of the interaction The irrigation with 120 % of the evapotranspiration and foliar spray with seaweed extract gave the highest values of all growth characteristics of taro plant , expressed as plant height, number of leaves, leaf area, total chlorophyll and dry matter of leaves. Chemical composition of leaves a. Effect of irrigation levels The heighest level of soil moisture, i.e. irrigation with 120 % of the evapotranspiration, gave the highest values of N, P, K, Ca and Mg content in leaves. b. Effect of foliar spray substances N, P, K, Ca and Mg content in leaves were significantly affected by foliar spray substances. Seaweed extract increased all values of N, P, K, Ca and Mg content in leaves. . c. Effect of the interaction Using seaweed extract with irrigation at 120 % of the evapotranspiration gave the highest values of N, P, K, Ca and Mg. 3. Chemical composition of corms a. Effect of of irrigation levels Irrigation with 120% of the evapotranspiration achieved a significant increase in nitrogen, phosphorus, potassium, total carbohydrates, and starch on taro corms. b. Effect of foliar spray substances Spraying of taro plants with seaweed extract showed the best results of nitrogen, phosphorus, potassium, total carbohydrates, and starch taro corms. c. Effect of the interaction The interaction between the highest irrigation levels and foliar spray with seaweed extract gave significantly the highest percentage of nitrogen, phosphorus, potassium, total carbohydrates, and starch of taro corms. 4. Yield and its components a. Effect of irrigation levels spray substances Total yield and its components (corm height, diameter, dry matter, yield per plant and per fedd) were significantly influenced by water supply. Thus, The highest values were obtained from plants irrigated with 120 % of the evapotranspiration compared with 100,80 and 60 % levels. b. Effect of foliar spray substances Seaweed extract showed the best results of taro yield and its components (corm height, diameter, dry matter, yield per plant and per fedd ). c. Effect of the interaction Corm height ,diameter, dry matter, yield per plant and per fedd. were significantly increased in taro plants irrigated with using 120% of evapotranspiration and spraying with seaweed extract compared with the other combinations. 5. Water use efficiency a. Effect of of irrigation levels The greatest value of water use efficiency was obtaind due to the irrigation level at 80% of evapotranspiration, while 120% of the evapotranspiration decreased water use efficiency. b. Effect of foliar spray substances Seaweed extract recorded the highest values of water use efficiency compared with potassium silicate and abscisic acid . c. Effect of the interaction The highest value of water use efficiency was obtaind in plants grown under irrigation level at 80% of the evapotranspiration and sprayed with seaweed extract. |