Nitrogen and Potassium Fertilization in a Guava Orchard Evaluated for Five Cycles: Effects on the Plant and on Production

Abstract

Guava response to fertilization can be monitored through plant tissue analysis. Correct interpretation of these results, based on standard levels, is of great importance for correct nutrient management of the crop. However, standard levels are constantly criticized for not considering interactions among elements. To improve the nutritional diagnosis of 'Paluma' guava (Psidium guajava L., Myrtaceae), an experiment was conducted using nitrogen fertilization (0, 0.5, 1.0, and 2.0 kg per plant per cycle of N, with urea as a source with 45 % N), and potassium fertilization (0, 0.55, 1.1, and 2.2 kg per plant per cycle of K 2 O, with potassium chloride as a source with 60 % K 2 O) in an irrigated commercial area for five consecutive cycles, 2009 through 2012, observing the influence of fertilizers and climate and assessing yield and leaf element content, using the concept of isometric log ratios (ilr) to interpret leaf analysis results (N, P, Ca, Mg, K, and S). This paper showed that nutrient balances and nutrient concentration values can be interpreted coherently using compositional data analysis. Ranges of nutrient balances also were established for "Paluma" guava and validated through ranges grounded in nutrient contents currently used in Brazil. Nitrogen fertilization increased "Paluma" guava yield. The 0.5 kg N application rate per plant and the other studied treatments practically showed the same results, and their values were affected by pruning time as well as the nutrient balances.

Chemical properties of the soil fertilized with potassium and calcium in guava cultivation cv. 'Paluma'

“…The increase of the K 2 O doses linearly increased the levels of Ca in the soil, at 0.006 cmol c dm -3 level per unit increase of K 2 O, in the treatments without calcium nitrate ( Figure 2C). In the present study, the presence of Ca 2+ in the soil solution was observed in the presence of a high concentration of K in the root environment as shown by (Amini et al, 2012;Montes et al 2016a). As for the soil with calcium nitrate, it is possible to observe a reduction in the availability of Ca 2+ in the minimum estimated dose of K 2 O of 83 g plant -1 year -1…”

“…Specifically in guava, the need for fertilization to raise productivity and maintain orchard sustainability becomes a constant need (Kumar et al, 2014). These soil conditions determine the development of the plant root system, which is directly associated with plant growth and nutrition (Montes et al, 2016a). The high mobility of nutrients into the soil, such as K can be strongly influenced by changes in management and fertilization of culture (Moges et al, 2013).…”

Adubação com potássio e cálcio na nutrição e produção de goiabeira 'Paluma'

“…Possivelmente, o excesso de K aplicado nos tratamentos das maiores doses pode ter causado um desbalanço nutricional entre o K e outros nutrientes, contribuindo para a redução do crescimento e, consequentemente, para a redução de produção da cultura (Andrade Junior et al, 2005). Para realização da adubação potássica deve-se considerar o equilíbrio entre o K e cátions como Ca e Mg, pois cátions monovalentes são absorvidos pelas raízes das plantas mais rapidamente que os bivalentes; assim, uma relação adequada entre eles é fundamental para aumentar a eficiência de absorção (Montes et al, 2016).…”

“…A goiabeira (Psidium guajava L.) é uma frutífera tropical, originária das Américas do Sul e Central, que pode ser encontrada em todo o território brasileiro. Seus frutos apresentam sabor agradável, elevado valor nutricional e boa aceitação pelos consumidores, podendo ser consumidos in natura ou utilizados nas agroindústrias de processamento (Montes et al, 2016).…”

Effects of exotic guava (Psidium guajavaL.) invasion on soil properties in Limpopo, South Africa

“…Much of the research work on changes in soil physico‐chemical properties underneath guava trees are from an agricultural standpoint, with the aim of increasing guava production for economic benefits (Montes et al, ; Sharma, Wali, Bakshi, & Jasrotia, ). To our knowledge, no study has examined how guava invasion in natural ecosystems changes soil physico‐chemical properties.…”