Testing of Controlled Release Fertilizer Programs for Seep Irrigated Irish Potato Production

Abstract

A Best Management Practices (BMP) program has been implemented for Northeast Florida potato (Solanum tuberosum) producers to reduce the potential for nitrate (NO 3 ) leaching from the 9000 ha of land in potato production in the St. Johns River watershed. Controlled release fertilizers (CRFs) could supply nutrients to potatoes while reducing the potential for off-site movement of nutrients thus, providing a long-term solution to the problem of NO 3 leaching on sandy soils. The objectives of this project were to evaluate the quality and quantity of potatoes fertilized with CRFs # 1709 and soluble fertilizers and to determine the influence of nitrogen (N) source on N use efficiency (NUE). Fertilizer treatments were: (a) no N control; (b) ammonium nitrate (AN) and urea; (c) polymer coated urea (PCU) and polymer sulfur coated urea (PSCU); (d) polymer coated 11-11-11 product; and (e) polymer coated 15-9-12 product. Fertilizers treatments were each applied 112, 168, and 224 kg ha À1 . The highest total and marketable yields were obtained with CRF 15-9-12 (224 kg N ha À1 ), PCU þ PSCU (168 kg N ha À1 ), and AN þ Urea (224 kg N ha À1 ) averaging 44.2 and 39.9 MT ha À1 respectively, across the three treatments. Total and marketable yield for the no N treatment were 11.2 and 9.3 MT ha À1 , respectively. All leaf N levels were within the sufficient range except for plants in the no N, AN þ urea (112 kg N ha À1 ), PCU þ PSCU (112 kg N ha À1 ), and CRF 11-11-11 (112 and 168 kg N ha À1 ). Nitrogen removal by plant tissue ranged from a high of 94.3 kg N ha À1 to a low of 10.7 kg N ha À1 for the 15-9-12 (224 kg ha À1 ) and no N treatments, respectively. At low N rates, CRFs had higher NUE than the soluble fertilizers. Nitrogen use efficiency was similar among all fertilizer sources at higher N rates.

Strategies for improving nitrogen use efficiency: A review

“…Urea and urea based fertilizer when surface-applied and not incorporated immediately into the soil are more prone to volatilization losses. This mechanism of N loss is more severe in alkaline soil and warm sunny condition, under this condition as much as 20% of N may volatilize and lost to atmosphere within a week (Hutchinson et al, 2003).…”

“…ambient temperature, solar budget, amount of rainfall and relative humidity are the important external factors influencing crop health as well as its demand for N (Hutchinson et al, 2003). How these above mentioned variables and their interactions are going to affect the performance of any crop or cropping sequence greatly relied on the agro-climatic conditions of the region where the crop is grown (Kravchecko et al, 2003).…”

“…Conventionally, to fulfil this large requirement of N, farmers completely depend on chemical nitrogen. Excess use of N as crop input can cause disrupts its transformation and natural movement among its various pools resulted in imbalance of several ecosystem function and services (Hutchinson et al, 2003;Meena et al, 2014). Sustainable agriculture production requires balanced and judicious, efficient, eco-friendly, and environmentally sound management practices.…”

Nutrient Mobility and Availability with Selected Irrigation and Drainage Systems for Vegetable Crops on Sandy Soils

“…The NUE for N ranged between 10% and 32% for uncoated fertilizer and between 79% and 94% for coated fertilizers when peanut was grown on a sandy soil (Typic Udipsamment), Japan under drip irrigation with N application rates of 30 to 120 kg ha -1 (Wen et al, 2001). Seepage-irrigated Irish potato produced on Elley fine sand (90-95% sand), USA had a significantly higher NUE for N with CRFs treatment compared with soluble fertilizer treatment only when 112 kg N ha -1 was www.intechopen.com applied, but not when 168 and 224 kg N ha -1 were applied (Hutchinson et al, 2003). Other studies showed similar results of higher NUE for N with CRFs compared with soluble fertilizers only with lower N application rate applied, but not with higher rate (140 vs. 280 kg N ha -1 ; Zvomuya et al, 2003;and 146 vs. 225 kg N ha -1 ;Pack et al, 2006; both for potato production on sandy soils).…”

Análise Do Potencial Tecnológico De Revestimentos Em Fertilizantes Nitrogenados Melhorados Na Liberação Controlada De Nutrientes

“…Em alguns fertilizantes revestidos são atribuídos múltiplas funções em decorrência do revestimento empregado, como exemplo, um fertilizante nitrogenado revestido com as propriedades de liberação lenta e retenção de água, um poli reticulado preparado (ácido acrílico) /organo-attapulgite (revestimento externo), uréia-formaldeído (revestimento interno), e uréia grânulo (no centro do grânulo). Estes fertilizantes possuem uma ampla aplicação na área da agricultura e horticultura, principalmente em áreas propensas a seca, devido a sua retenção de água ser bastante eficiente e ter uma liberação lenta dos nutrientes no ambiente onde é empregado devido às múltiplas camadas de revestimento aplicado (LIU et al, 2012).Alguns fertilizantes são revestidos com materiais impregnados em polímeros com o objetivo de uma liberação controlada de nutrientes no solo, a exemplo, um polímero revestido e adicionado e este o enxofre, reveste a uréia, no qual o enxofre pode ser misturado ou impregnado superficialmente no polímero (HUTCHINSON et al, 2003).Outros fertilizantes são desenvolvidos com revestimentos que também lhe confere um aumento na dureza, além das propriedades de liberação lenta dos nutrientes, por exemplo, um estudo efetuado para desenvolver um novo fertilizante de liberação lenta, o qual é baseado em argilas naturais atapulgite como uma matriz, a goma guar como um revestimento interno em relação a ultima camada, e goma de guar-g-poli (ácido co-itacónico-acrilamida)/ácido húmico polímero superabsorvente como um revestimento externo. Os grânulos de fertilizante composto, revestidos com diâmetro na faixa de 2-3 mm, além de possuir um baixo teor de humidade, possuem elevada dureza mecânica (LIU et al, 2012).…”