Integrated Use of Potassium and Soil Mulching on Growth and Productivity of Garlic (Allium sativum L.) under Deficit Irrigation

This study was carried out during the winter seasons of 2016 and 2017 at private farm in Beni Suief Governorate, Egypt to investigate the integrative use of potassium levels (24, 48, 72 and 96 kg K2O fed(-1)) and soil mulching (rice straw and bare soil) on growth and productivity of garlic under three levels of surface irrigation (60, 80 and 100 % of crop evapotranspiration (ETc)). The experimental layout was a spit-spilt plot system based on Randomized Complete Blocks Design. Irrigation levels, potassium rates and mulch types were randomly allocated in the main, sub and sub-sub plots, orderly. The obtained results showed that, the amount of irrigation at 80 and/or 100 % ETc was accompanied increases by plant height, leaves number, leaf area and dry weight plant(-1), total bulbs yield, individual bulb weight, cloves weight and number bulb(-1) compared to irrigation 60 % ETc. The application of potassium from 24 to 48 and further to 72 and 96 kg K2O fed(-1) gave gradual increments in the aforementioned growth and productivity of traits. The rice straw mulch augmented all previous growth, total bulbs yield and its components compared to bare soil. Generally, the 1st order interaction between irrigation percent at 100 and/or 80 % ETc x potassium rate at 96 and/or 72 kg K2O fed(-1), irrigation percent at 80 and/or 100 % ETc x rice straw, potassium rate at 96 kg K2O fed(-1) x rice straw and the 2nd interaction of irrigation percent at 100 % ETc x potassium rate at 96 kg K2O fed(-1) x rice straw mulch had pronounced effects on morphological characters and bulbs yield and its components compared to other combined treatments.