Nitrogen and potassium fertilization on cabbage biometrics and foliar nutritional levels

Abstract

Among the most absorbed nutrients by cabbage, nitrogen (N) and potassium (K) are the most extracted; thus, the objective of this study was to evaluate the responses of N and K fertilization on the cabbage biometrics and foliar levels of macro and micronutrients. Four N doses (0, 75, 150, 300 kg ha -1 of N) and four K doses (0, 75, 150, 300 kg ha -1 of K2O). Biometrics of cabbage head (height, circumference and diameter) and productivity were evaluated. The cabbage levels of macro and micronutrients were also evaluated in leaves of plants at the phenological stage of head-formation. Nitrogen fertilization did not significantly affect the variables evaluated mostly due to the great natural fertility of the experimental soil area. This lack of response highlights the importance of constant monitoring of the nutritional status of the productive area to avoid nonnecessary N fertilization. The lowest Mg leaf content was observed at 88 kg ha -1 of K2O, after which the Mg leaf content increased. The foliar Zn was reduced in doses after 133 kg ha -1 of K2O. The cabbage head diameter and circumference decreased with the increase of the K2O doses. The cabbage head height increased up to 128 kg ha -1 of K2O. The decreasing sequence of the macro and micronutrient levels in cabbage leaves followed the sequence K>Ca>N>S>Mg>P and Mn>Fe>B>Zn>Cu regardless of the level of the factors applied. Keywords: Brassica oleracea var. capitata, crop yield, plant mineral nutrition Entre os nutrientes mais absorvidos pela cultura do repolho, o nitrogênio (N) e o potássio (K) são os mais extraídos. Assim, o objetivo deste estudo foi avaliar as respostas da fertilização de N e K sobre a biometria de repolho e os níveis foliares de macro e micronutrientes. Quatro doses de N (0, 75, 150, 300 kg ha -1 de N) e quatro doses de K (0, 75, 150, 300 kg ha -1 de K2O). Foram avaliadas a biometria da cabeça de repolho (altura, circunferência e diâmetro) e produtividade. Os níveis de macro e micronutrientes nas folhas de repolho também foram avaliados na fase fenológica da formação da cabeça. A fertilização nitrogenada não afetou significativamente as variáveis avaliadas principalmente devido à grande fertilidade natural da área experimental do solo. A falta de resposta destaca a importância do monitoramento constante do estado nutricional da área produtiva para evitar fertilizações nitrogenadas desnecessárias. O menor teor foliar de Mg foi com a aplicação de 88 kg ha -1 de K2O, após esta dose o teor foliar de Mg aumentou. O Zn foliar foi reduzido em doses superiores s 133 kg ha -1 de K2O. O diâmetro da cabeça de repolho e a circunferência diminuíram com o aumento das doses de K2O. A altura da cabeça do repolho aumentou com a aplicação de até 128 kg ha -1 de K2O. A sequência decrescente dos níveis de macro e micronutrientes nas folhas de repolho seguiu a sequência K>Ca>N>S>Mg>P e Mn>Fe>B>Zn>Cu independentemente do nível dos fatores aplicados. Palavras-chave: Brassica oleracea var. capitata, produção agrícola, nutrição mineral de plantas

Effect of Nano-DAP on Soil Characteristics and Qualities of Cabbage

“…In case of available soil potassium, combined effect of different doses of treatments resulted in higher level of soil potassium which might have increased the quantity of potassium in the soil, respectively. Similar positive results were also observed by Silva et al [18].…”

“…This might be as a result of the soil receiving more potassium and the bacteria making it readily available to the plant. Silva et al [18] also observed rise in N and K content due to the combined effect of various fertilizer doses.…”

Impact of Nano-Dap on Growth and Development of Cabbage

“…Analyses on cabbage conducted by Nath [6] and Sumanth [7] confirm this conclusion. Also similar results were observed by Chamuah et al, [8] and Silva et al, [9] in cabbage.…”