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

[摘要] English: It is well known that appropriate band applications of N and/or K can result in optimum earlygrowth and development of maize. Two pot experiments were conducted in a glasshouse atthe University of the Orange Free State, Bloemfontein to determine the application levels atwhich the above mentioned phenomena occur. The first experiment was conducted todetermine the influence of band placed N and/or K on the early growth and development ofmaize, while the second experiment was set up to determine the influence of K placementthrough banding, topdressing and a combination of banding and topdressing on the earlygrowth and development of maize.The first experiment was conducted from January to March 1999 with the cultivarPAN 6479. Two types of soil were used in the experiment, viz. a sandy loam soil collectedfrom Ficksburg and a sandy soil collected from Boshof The plant density was maintained atthree 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 thisexperiment. The application rates were the equivalent of 0, 20, 40 and 60 kg N or K.ha-¹ fora row spacing of 1.5 m.The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize weremeasured to determine the influence of different N and/or K applications on the early growthand development of maize. All the plant parameters measured showed that the interaction ofN and K applications had no significant influence on the early growth and development ofmaize. The best results were obtained with an application of 20 to 40 kg N.ha-¹�?Anapplication of 20 kg K.ha-¹ provided the best results.The second experiment was conducted from October to November 1999. With the exceptionof the fertilization procedure, all other aspects pertaining to the execution of this experimentwere the same as those used in the first experiment. This experiment was terminated sixweeks after seedling emergence. The experiment consisted of two main factors, viz. fourlevels and three methods of K application, arranged in a factorial combination in a completerandomized 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 andtopdressing for a row spacing of 1.5 m. With regards to the combination application, half ofK was banded and another half topdressed.The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize were studiedto determine the effect of different levels of banded, top dressed and a combination of bandedand topdressed K on the early growth and development of maize. All the plant parametersstudied showed that the interaction of K application levels and methods had no significantinfluence on the early growth and development of maize. It seems the best results wereattained with °to 20 kg K.ha-¹ The second experiment was conducted from October to November 1999. With the exceptionof the fertilization procedure, all other aspects pertaining to the execution of this experimentwere the same as those used in the first experiment. This experiment was terminated sixweeks after seedling emergence. The experiment consisted of two main factors, viz. fourlevels and three methods of K application, arranged in a factorial combination in a completerandornized 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 andtopdressing for a row spacing of 1.5 m. With regards to the combination application, half ofK was banded and another half topdressed.The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize were studiedto determine the effect of different levels of banded, top dressed and a combination of bandedand topdressed K on the early growth and development of maize. All the plant parametersstudied showed that the interaction of K application levels and methods had no significantinfluence on the early growth and development of maize. It seems the best results wereattained with °to 20 kg K.ha-¹. A combination of banding and topdressing in the sandy loamsoil 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 theseglasshouse results under field conditions.The second experiment was conducted from October to November 1999. With the exceptionof the fertilization procedure, all other aspects pertaining to the execution of this experimentwere the same as those used in the first experiment. This experiment was terminated sixweeks after seedling emergence. The experiment consisted of two main factors, viz. fourlevels and three methods of K application, arranged in a factorial combination in a completerandornized 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 andtopdressing for a row spacing of 1.5 m. With regards to the combination application, half ofK was banded and another half topdressed.The aerial and subsoil plant parameters, as well as, the nutrient uptake by maize were studiedto determine the effect of different levels of banded, top dressed and a combination of bandedand topdressed K on the early growth and development of maize. All the plant parametersstudied showed that the interaction of K application levels and methods had no significantinfluence on the early growth and development of maize. It seems the best results wereattained with °to 20 kg K.ha-¹. A combination of banding and topdressing in the sandy loamsoil 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 theseglasshouse results under field conditions.. A combination of banding and topdressing in the sandy loamsoil 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 theseglasshouse results under field conditions.

[发布机构] University of the Free State