Fluorescência transiente da clorofila a e crescimento vegetativo em cafeeiro conilon sob diferentes fontes nitrogenadas

Abstract

O uso de fertilizantes nitrogenados é um recurso eficaz para elevar a produtividade do cafeeiro, de modo que o aprimoramento e/ou geração de novas técnicas que auxiliem no manejo da adubação nitrogenada são fundamentais, pois contribuirão para aumentar a eficiência de uso do nitrogênio (N). Dessa forma, objetivou-se determinar a fluorescência transiente da clorofila a e o crescimento vegetativo do cafeeiro Conilon sob diferentes fontes nitrogenadas. O experimento foi realizado em Nova Venécia - ES - Brasil, em lavoura de café Conilon cultivar “Vitória Incaper 8142”. Foram avaliadas cinco fontes de adubos nitrogenados: ureia comum, ureia + NBPT, ureia + Cu e B, ureia + S, e nitrato de amônio. A fluorescência máxima da clorofila a não diferiu em nenhuma das épocas analisadas. Os valores de índice relativo de clorofila (IRC) alternaram suas significâncias com relação aos tratamentos ao longo das datas de avaliação. As fontes de N não foram responsáveis, isoladamente, pelas alterações do IRC. As fontes de fertilizantes nitrogenados de eficiência aumentada apresentam baixa influência na fluorescência transiente da clorofila a e não influenciam o crescimento vegetativo do cafeeiro.

Agronomic characteristics and quality of lettuce cultivars in different crop seasons in western Alagoas, Brazil

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Análise comparativa dos compostos bioativos do rizoma de açafrão in natura (Curcuma longa L.) e seu condimento comercial em pó

“…The addition of saffron when cooking rice can be a great alternative to increase the general population's daily consumption of anthocyanins, given that anthocyanin is also a type of antioxidant, which is known as a plant-derived bioactive compound, thus promoting health, slowing the aging process and preventing disease. As a result, antioxidant constituents in plant material awakened the interest of scientists, food manufacturers, cultivators, and consumers due to the role they play in maintaining human health [35][36][37][38][39][40][41]. Although carotenoids are widely distributed in fresh saffron systems, analyses have only focused on some compounds that are involved in aspects of human health, considering that in biological systemsespecially the human systemthey behave as antioxidants and prooxidants, under different conditions; besides, α-carotene and β-carotene are precursors of retinol biosynthesis (vitamin A).…”

Soil chemical properties and nutrition of conilon coffee fertilized with molybdenum and nitrogen

“…Economic factors related to the production process make urea the most used nitrogen fertilizer in world agriculture (Silva et al, 2011). Due to the easily acquisition, high concentration of N, lower cost per kilogram of N, low corrosivity, and high solubility, urea is the most used source of N in C. canephora crops (Oliosi et al, 2017).…”