Effect of Calcium Chloride, Potassium Humate and Fulvic Acid on Growth and Productivity of Jerusalem Artichoke (Helianthus tuberosus L.) under Water Stress.

This study was carried out to investigate the impact of adding potassium humate and fulvic acid to the soil and spraying calcium chloride under various irrigation levels on the growth,productivity and the chemical content of Jerusalem artichoke tubers during the two successive summers of 2020 and 2021 at a private farm in El-Kaluobia Governorate, Egypt. This study included three irrigation treatments (100 %, 80 % and 60 % of evapotranspiration (ETp) in the main plots), adding potassium humate (2000 and 3000 ppm) and fulvic acid (2000 and 3000 ppm) to the soil and foliar application of calcium chloride (500 and 1000 ppm) to the plantsin the sub plots. The results showed that irrigation levels of 100% followed by 60% (ETp) increased growth and yield. Furthermore, the soil addition of potassium humate at 3000 ppm and fulvic acid at 2000 ppm produced the highest plant height, number of lateral shoots, fresh and dry weight, total yield, average tuber weight, dry matter and inulin content. The best interaction resulted in significantly increased growth, yield, and its components when fulvic acid was present at 2000 ppm under 60% (ETp) and potassium humate at 3000 ppm under 100% (ETp). The study recommended the ground application of fulvic acid at 2000 ppm under 60% (ETp) since, it significantly improved the studied traits and was effective in saving water consumption by 40% of the recommended amount, when planting Jerusalem artichoke.