RESPONSE OF SUGAR BEET TO SANDY SOIL AMENDED BY ZEOLITE AND POTASSIUM SULFATE FERTILIZATION

Two field experiments were carried out on a private farm at Wadi El-Natrun (latitude of 30.48° N and longitude of 30.50° E), Beheira Governorate, Egypt, in the 2019–2020 and 2020–2021 seasons, to find out the effect of adding zeolite as a soil conditioner and potassium fertilizer on growth, yield, and quality of sugar beet crop (Beta vulgaris L. var. saccharifera) grown in sandy soil conditions. The present work included 12 treatments, which were the combinations of four zeolite levels (Zero, 476, 952, and 1,428 kg ha-1), and three levels of potassium in the form of potassium sulfate (119, 178.5, and 238 kg K2SO4 ha-1), which were added as a soil application. The treatments were arranged in a complete block design in a split plot with four replications. The results showed that higher values of the photosynthetic pigments, root diameter, fresh and foliage weights plant-1, as well as, sucrose and extracted sugar percentages, quality index, yields of the root, top, and sugar ha-1, were obtained by adding 1,428 kg zeolite, compared with the other levels of zeolite, in both seasons. However, sodium, alpha-amino N contents in the root, and sugar lost to molasses% were insignificantly affected by zeolite rates in both seasons. Application of 238 kg K2SO4 ha-1 significantly resulted in the highest values of photosynthetic pigments, root dimensions, sucrose%, and root potassium content. In addition, extracted sugar %, quality index, root, top, and sugar yields ha-1 were increased compared with the other lower K-sulphate levels in both seasons. On the contrary, sugar lost to molasses% was insignificantly affected by applied potassium sulfate in both seasons. The maximum values of root diameter, fresh weight, yields of root and top ha-1 in both seasons, and also sugar yield in the second season were produced from the interaction between applying 1,428 kg zeolite and 238 kg potassium sulfate ha1.