Influence of nitrogen and potassium applications on the early growth and development of maize (Zea mays L.)

English: It is well known that appropriate band applications of N and/or K can result in optimum early growth and development of maize. Two pot experiments were conducted in a glasshouse at the University of the Orange Free State, Bloemfontein to determine the application levels at which the above mentioned phenomena occur. The first experiment was conducted to determine the influence of band placed N and/or K on the early growth and development of maize, while the second experiment was set up to determine the influence of K placement through banding, topdressing and a combination of banding and topdressing on the early growth and development of maize. The first experiment was conducted from January to March 1999 with the cultivar PAN 6479. Two types of soil were used in the experiment, viz. a sandy loam soil collected from Ficksburg and a sandy soil collected from Boshof The plant density was maintained at three plants per pot and the experiment was terminated four weeks after seedling emergence. A complete randomized design with a factorial combination consisting of two main factors, viz. four N and/or K band application levels which were replicated thrice, was used in this experiment. The application rates were the equivalent of 0, 20, 40 and 60 kg N or K.ha-¹ for a row spacing of 1.5 m. The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize were measured to determine the influence of different N and/or K applications on the early growth and development of maize. All the plant parameters measured showed that the interaction of N and K applications had no significant influence on the early growth and development of maize. The best results were obtained with an application of 20 to 40 kg N.ha-¹• An application of 20 kg K.ha-¹ provided the best results. The second experiment was conducted from October to November 1999. With the exception of the fertilization procedure, all other aspects pertaining to the execution of this experiment were the same as those used in the first experiment. This experiment was terminated six weeks after seedling emergence. The experiment consisted of two main factors, viz. four levels and three methods of K application, arranged in a factorial combination in a complete randomized design with four replications. The application rates were the equivalent of 0, 20, 40 and 60 kg K.ha-¹ placed through banding, topdressing and a combination of banding and topdressing for a row spacing of 1.5 m. With regards to the combination application, half of K was banded and another half topdressed. The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize were studied to determine the effect of different levels of banded, top dressed and a combination of banded and topdressed K on the early growth and development of maize. All the plant parameters studied showed that the interaction of K application levels and methods had no significant influence on the early growth and development of maize. It seems the best results were attained with °to 20 kg K.ha-¹ The second experiment was conducted from October to November 1999. With the exception of the fertilization procedure, all other aspects pertaining to the execution of this experiment were the same as those used in the first experiment. This experiment was terminated six weeks after seedling emergence. The experiment consisted of two main factors, viz. four levels and three methods of K application, arranged in a factorial combination in a complete randornized design with four replications. The application rates were the equivalent of 0, 20, 40 and 60 kg K.ha-¹ placed through banding, topdressing and a combination of banding and topdressing for a row spacing of 1.5 m. With regards to the combination application, half of K was banded and another half topdressed. The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize were studied to determine the effect of different levels of banded, top dressed and a combination of banded and topdressed K on the early growth and development of maize. All the plant parameters studied showed that the interaction of K application levels and methods had no significant influence on the early growth and development of maize. It seems the best results were attained with °to 20 kg K.ha-¹. A combination of banding and topdressing in the sandy loam soil and topdressing alone in the sandy soil provided the best results. Finally, it is recommended that field trials should be conducted in order to verify these glasshouse results under field conditions.The second experiment was conducted from October to November 1999. With the exception of the fertilization procedure, all other aspects pertaining to the execution of this experiment were the same as those used in the first experiment. This experiment was terminated six weeks after seedling emergence. The experiment consisted of two main factors, viz. four levels and three methods of K application, arranged in a factorial combination in a complete randornized design with four replications. The application rates were the equivalent of 0, 20, 40 and 60 kg K.ha-¹ placed through banding, topdressing and a combination of banding and topdressing for a row spacing of 1.5 m. With regards to the combination application, half of K was banded and another half topdressed. The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize were studied to determine the effect of different levels of banded, top dressed and a combination of banded and topdressed K on the early growth and development of maize. All the plant parameters studied showed that the interaction of K application levels and methods had no significant influence on the early growth and development of maize. It seems the best results were attained with °to 20 kg K.ha-¹. A combination of banding and topdressing in the sandy loam soil and topdressing alone in the sandy soil provided the best results. Finally, it is recommended that field trials should be conducted in order to verify these glasshouse results under field conditions.. A combination of banding and topdressing in the sandy loam soil and topdressing alone in the sandy soil provided the best results. Finally, it is recommended that field trials should be conducted in order to verify these glasshouse results under field conditions.