IMPROVEMENT OF PERFORMANCE AND PRODUCTIVITY OF POTATO PLANTS VIA ADDITION OF DIFFERENT ORGANIC MANURES AND INORGANIC POTASSIUM SOURCES

The Egyptian government is eager to increase the production of strategic crops e.g., potato, especially that grown on degraded soils to face the escalating population increase. It is known the importance of organic fertilization for potato tubers; however, there is no consensus among the researchers in the plant nutrition field on the best organic source that should be used, where the opinions differ in this regard. Also, it is known the vital role of potassium (K) in sizing agents for potato tubers but there is no consensus on the best potassium source that should be used. So, this research work was executed aiming to assess the effect of soil addition of different organic sources before planting i.e., ChM, plant residues compost and FYM as main plots and K fertilization under fertigation system via different K sources [potassium nitrate (46.0 % K2O), potassium silicate (K2SiO3, 60.0 %K), potassium citrate (K3C6H5O7, 45.0 % K2O), potassium sulphate (K2SO4, 48.0 % K2O)] as sub main plots on performance growth, tubers quality and productivity of potato ̎Cv Spuntaʺ plant grown on sandy loam soil located in the North Nile Delta of Egypt during the growing season of 2022.

The findings indicate that the maximum values of all studied parameters which express the performance growth, tubers quality and productivity e.g., plant height, fresh and dry weights, chlorophyll content, average weight of one tuber, No. of tuber plant-1, total tuber yield, total carbohydrates, total sugars, dry matter, total dissolved solids were recorded when the potato plants treated with the ChM amendment followed by that treated with plant residues compost and lately potato plants treated with FYM. On the other hand, potato plants fertilized with potassium silicate recorded the best performance growth, tubers quality and productivity in comparison with that fertilized with other studied K sources, where potassium nitrate form came in the second order followed by potassium citrate, while the potassium sulphate form came in the last order. With the note that the significant difference between potassium nitrate and silicate wasn't great, but there were no significant differences between both forms in some characteristics e.g., chlorophyll, N and K contents in leaves. Also, available soil N, P and K after harvest pronouncedly improved due to all studied treatments.

Generally, the treating potato with the combined treatment of ChM x potassium silicate was the best for optimizing potato production under sandy loam soil conditions.