Produtividade da batata sob diferentes regimes de irrigação por aspersão convencional e gotejamento no sul de Minas Gerais

• Autor(a) principal: Souza, Darik Oliveira
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5224
• topic: Batata; Irrigação; Potato; Irrigation; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::AGROMETEOROLOGIA

Potato plant (Solanum tuberosum L.) is one of the main species cultivated worldwide, playing an important role as source of food, generating labor and income. In southern Minas Gerais, one of the major potato-producing regions in Brazil, cultivation is carried out throughout the year under total or supplementary irrigation. However, irrigation management practices are often not correctly adopted by farmers, leading to diminished product productivity and quality. This work aimed to evaluate the effect of different irrigation water depths and regimens on total productivity and quality of potato plants under field condition. The assay was developed at the Fazenda São Geraldo, located in the municipality of São Gonçalo do Sapucaí in southern Minas Gerais, from May to September 2007. The Agata variety potato plant was sown under two irrigation systems: drip-irrigation and conventional aspersion (sprinkler). For the drip-irrigation system, a split-plot design was arranged at three irrigation frequencies (F1 = 2 days, F2 = 4 days and F3 = 6 days) in the plots in a randomized block design, with four repetitions and four water depths, with the latter being in function of the total irrigation needed-ITN: (L1 = 0.75 ITN, L2 = ITN, L3 = 1.25 ITN and L4 = 1.5 ITN) in the split-plots. Under the conventional aspersion system, the assay applied two irrigation frequencies (F1 = 4 days and F2 = 6 days), four repetitions and four water depths (L1 = 0.8 ITN, L2 = ITN, L3 = 1.1 ITN and L4= 1.25 ITN), followed by regression analysis. Evaluation of the results took into account total production, and large-sized ( &#8805; 45 mm) and smallsized (< 45 mm) potato production. The use of different water depths was recommended using the program Irriplus®. Total mean evapotranspiration of the potato plant varied from 163.5 to 172.7 mm and 181.0 to 186.4 mm, under dripirrigation and conventional aspersion, respectively. The phenological cycle of the culture was of 119 days (planting to harvest). Under the drip-irrigation system, the lowest water depths applied were 156, 153.1 and 140.6 mm, corresponding to treatment 0.75 ITN, at 2-, 4-and 6-day frequencies, respectively. The highest water depths applied were 177.9; 188.5 and 188 mm, for treatment 1.5 ITN at 2-, 4-and 6-day irrigation frequencies, respectively. Under the conventional aspersion system, the smallest water depths (treatment 0.8 ITN), were 133.3 and 129.5 mm at frequencies of 4 and 6 days, respectively. The highest water depths, (treatment 1.25 ITN), reached values of 209.3 and 203.4 mm at 4-and 6-day frequencies, respectively. Total mean productivity of the large-sized Agata variety potato using drip-irrigation was 61 and 50.3 t ha-1, respectively, with no satisfactory fit being obtained for regression models. For large-sized potato production under conventional aspersion at 4-and 6-day frequencies, maximum production points were obtained, corresponding to water depth values of 0.99 and 1.05 ITN. For total potato production, under conventional aspersion, at 6-day frequency, a maximum production point was obtained corresponding to water depth of 1.06 ITN. The highest potato productivities under conventional aspersion were attained at the 4-day irrigation frequency.