The role of some natural extracts in improving the growth and productivity of local red onion Allium cepa L. in quantity and quality

Abstract

The experiment was carried out during two seasons2016 / 2017 and  2017/ 2018 using local red onion variety. The objective was to improve the quality and quantity of onion production and to reduce the negative effects of excessive chemical fertilizers that is through study the effect of foliar spraying with concentration of Licorice roots and dry yeast extract on plant growth, and bulbs’ qualitative and quantitative characteristics. Spraying treatments using 4 different concentrations took place once plants had 4 true leaves at a rate of 4 times in total during the growing season and with a 15 day interval. The result showed positive effect of spraying treatments on vegetative growth, treatment with Licorice roots 15 g/L were significantly superior compared to all other treatments excluding leaf number and leaf area index in case of treatment with dry yeast 15 g/l. This positive effect on bulb yield (4.25, 3.91 kg/m² respectively), Bulbs had also better-quality characteristics, where dry matter content was 22.37, 21.97% (control 2.12 kg/m², 20.21%).

Key word: local onion, licorice roots, dry yeast, yield.