Long-term annual fertilization with nitrogen and potassium affect yield and mineral composition of 'Fuji' apple

Abstract

Nitrogen (N) and potassium (K) are closely related to orchard productivity, since they are usually found in higher concentrations than others macronutrients in apple (Malus × domestica Borkh) fruits. This research was carried out to assess the effect of eight years of soil additions of N and K on yield, fruit size and mineral composition of 'Fuji'/Marubakaido apple in São Joaquim, State of Santa Catarina, Southern Brazil. A factorial design was used with N and K annual fertilizer rates (0, 50, 100, 200 kg ha -1 of N and K 2 O) replicated in three orchards from 1998 to 2006. Yield was estimated by multiplying the total number of fruit per tree by the mean weight of 100 randomly sampled fruit. Fifteen days prior to harvest, 24 fruit pulps were analyzed for N, K, Ca and Mg contents. Increases in yields were noticed in five and four years, due to the N and K fertilizer additions, respectively. Fruit size was more affected by K than by N fertilization. Fruit mineral composition was affected by both N and K fertilization. N concentration and N:Ca ratios were enlarged by N fertilization. K concentration and K:Ca ratios were also enlarged by K fertilization. Ca fruit concentration was reduced by N fertilization and often by K. Ca-related fruit disorders were not observed even after 180 days storage. However, N and K fertilization affected Ca nutrition. Thus, when fertilizing with N and K, it is imperative to use combined practices in order to offset the detrimental effect that these nutrients may cause on Ca concentration in the fruit. Key words: Malus domestica Borkh, fertilization, production, nutrition de N e de K 2 O) e repetidas em três pomares comerciais. O rendimento foi estimado a partir da contagem do número total de frutos por planta e multiplicado pelo peso médio de 100 frutos amostrados aleatoriamente por parcela. Quinze dias antes da colheita, 24 frutos foram amostrados para fins de determinação das concentrações de N, K, Ca e Mg. As adubações nitrogenada e potássica aumentaram o rendimento da macieira em cinco e quatro dos oito anos avaliados, respectivamente. O tamanho dos frutos foi mais afetado pela adubação potássica que pela nitrogenada. As adições de N e K influenciaram a composição mineral dos frutos, incrementando suas concentrações e as relações N:Ca e K:Ca. A concentração de Ca nos frutos foi reduzida pela adubação nitrogenada e frequentemente pela potássica. Distúrbios fisiológicos relacionados com a deficiência de Ca não foram observados, mesmo após 180 dias de armazenagem. Entretanto, a nutrição do Ca foi influenciada pelas adubações nitrogenada e potássica. Por isso, ao aplicar-se N e K deve-se combinar práticas nutricionais que compensem a redução da concentração de Ca nos frutos que esses nutrientes promovem. ADUBAÇÕES ANUAIS COM NITROGÊNIO E POTÁSSIO POR LONGO PRAZO INFLUENCIAM O RENDIMENTO E A COMPOSIÇÃO MINERAL DE MAÇÃS 'FUJI' RESUMO: O nitrogênio (N) e o potássio (K) são os nutrientes mais exportados pelas maçãs (Malus

Advances on apple production under semiarid climate: N fertigation

“…Fruit production (kg plant -1 ), fruit yield and number of fruits per plant were not affected by nitrogen (N) fertilizing through fertigation that is in agreement with Nava and Dechen (2009) who identified no effect of N fertilizing during the first evaluation year and concluded that it had been caused by the buds that originated the fruits of the first harvest had already been differentiated in the previous year. Accordingly, both apple cultivars studied were adequately N supplied before the beginning of the experiment, whether compared to adequate range statement reported by Nachtigall et al (2004).…”

The Pear Tree Response to Phosphorus and Potassium Fertilization

“…This may cause low pear yield, and for that reason, phosphate and potassium fertilization is recommended as a safety measure to ensure greater yields (NAVA et al, 2008;DECHEN, 2009;SOUZA et al, 2013).…”

“…With the accumulation of available P and exchangeable K in soil surface layers and even in deeper layers, it is expected that part of these nutrients draws near the outside surface of the roots, especially through diffusion and, if taken up, contents of the nutrients will increase within the plant, and this may be diagnosed by the total content in the whole leaves (MELO et al, 2012;CURETTI et al, 2013). Therefore, an increase may be expected in the values of yield components, such as fruit weight, which may be reflected in an increase in fruit yield per plant and per area (NEILSEN et al, 2008;DECHEN, 2009). The aim of this study was to evaluate the response to phosphorus (P) and potassium (K) fertilization and to establish the critical levels of P and K in the soil and in the plant tissue in pear trees.…”

Produção e crescimento da macieira 'Fuji' em resposta à adubação orgânica e manejo de plantas espontâneas

“…Além de N, a cama de aviário é rica em K, sendo que este nutriente tende a aumentar o tamanho dos frutos. Nava et al (2009), avaliando a resposta da macieira Fuji à adubação nitrogenada e potássica, observaram que o K foi o nutriente que mais influenciou no tamanho de maçãs, uma vez que ele facilita a translocação de açúcares no interior na planta (TEIZ;ZEIGER, 2003). Apesar de a cama de aviário ter aumentado a massa média, os frutos ainda assim podem ser considerados pequenos na maioria das safras se comparados ao tamanho-padrão da cultivar Fuji, que geralmente origina frutos de tamanho médio a grande (CAMILO; DENARDI, 2002).…”