Estratégias de adubação com zinco para biofortificação agronômica do feijão-caupi

• Autor(a) principal: Alves, Larissa Venucia Freitag Varjão
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFMT
• Texto Completo: http://ri.ufmt.br/handle/1/4928
• topic: Saúde humana; Desnutrição; Micronutrientes; Qualidade de alimentos; Vigna unguigulata; CNPQ::CIENCIAS AGRARIAS; Human health; Malnutrition; Micronutrients; Food quality; Vigna unguigulata

Cowpea beans is among the most important foods in the population's diet, being recognized for its high nutritional value. The population has increased, thus some changes have happened in cropping systems and dietary habits, causing nutrient deficiency problems in almost half the world population. In this sense, research is being carried out to overcome this problem, such as biofortification, which aims to obtain cultivars with better nutritional quality. However, some studies have shown an inverse relationship between productivity and micronutrient concentrations in the grains. In this way, the aim of this study was to evaluate Zn application forms in cowpea, pointing at improving the nutritional quality of the beans and its influence on agronomic components of the crop. The experimental design was randomized blocks, in the 2 x 4 factorial scheme and 4 replicates. Two genotypes of cowpea were cultivated: BRS Guariba and BRS Xiquexique, being one of them, the most cultivated in Brazil and the other of high Zn content in the grains, chosen based on the biofortification research of the Embrapa-HarvestPlus Program, and four forms of Application of Zn: (i) without Zn application (control treatment); (ii) Zn soil application (Zn-S); (iii) Zn foliar application (Zn-F); (iv) Zn soil and leaf application (Zn -S+F). The application of Zn in the soil was carried out in the planting, with the supply of a solution that presented 4% of Zn (10 kg ha-1 of Zn). For the application of foliar Zn, a solution with 2% of zinc sulfate (ZnSO4H2O) was used, in an application rate of 800 L ha-1 (equivalent to 910 g ha-1 of Zn) and performed at the beginning of filling of the grains. The two experiments were carried out in the field, in 2016, in Barra do Garças-MT and Montes Claros de Goiás-GO., both under central pivot irrigation. Zn contents in the leaves and grains increased with application of this micronutrient, even in soils with contents above the critical level. There was no increase in productivity due to the application of Zn, however, there was an inverse relationship between productivity and Zn concentrations in cowpea beans. The accumulation of Zn in the grains was determined by the productivity differences of the cultivars, being higher in the commercial cultivar due to the high productivity. In thesis, the genotype environment interaction determines the productive potential and, consequently, also the nutritional quality of the grains. In this way, under the conditions of the present study, due to the low productivity of cultivars with potential for biofortification, the use of commercial cultivars with high productivity and application of Zn (in the soil or leaf spraying), raising the concentration and accumulation of the same in the grains. It is essential, in the programs of genetic improvement directed towards biofortification, to seek the increase of productivity for these cultivars.