Growth, productivity and quality of sugar beet as affected by antioxidants foliar application and potassium fertilizer top dressing

Abstract

To study the effects of antioxidants foliar application (without spraying, spraying with ascorbic acid "AA", salicylic acid "SA" and citric acid "CA", in addition, spraying with the mixture of AA+SA+CA) and potassium fertilizer levels as top dressing (12, 24, 36 and 48 kg K 2 O/fed, fed or feddan = 4200 m 2) on sugar beet growth, yields, its components and root quality. Two field experiments were conducted in Tag Al-Ezz, Agricultural Research Station Farm, Dakahlia Governorate, Agricultural Research Center, Egypt during 2012/2013 and 2013/2014 seasons. A strip-plot design with four replications was used. Results showed that highest growth attributes, yields and its components were resulted from foliar spraying twice with the mixture of antioxidants of 150 ppm of each of AA+SA+CA in both seasons. However, spraying with 150 ppm of AA came in the second rank. Highest Total Soluble Solids (TSS) and sucrose percentages were obtained from foliar spraying twice with 150 ppm of CA. In addition, highest apparent juice purity percentages were obtained from spraying twice with 150 ppm of SA in the first season and spraying twice with 150 ppm of CA in the second season. Fertilizing with 48 kg K 2 0/fed recorded highest growth attributes, root and top yields and its components in both seasons. While, fertilizing with 36 kg K 2 0/fed came in the second rank. Highest sugar yield/fed, TSS%, sucrose% and apparent juice purity% were obtained from fertilizing with 36 kg K 2 0/fed in both seasons. In order to maintain the agricultural resources, reduce environmental pollution and maximum sugar beet growth, yields and its attributes, it could be recommended that spraying twice with the mixture of antioxidants of 150 ppm of each of AA+SA+CA and mineral fertilizing with 36 kg K 2 O/fed as a top dressing application.