Influência de doses de Fósforo no rendimento da variedade de batata reno mondial nas condições do campo experimental da FAEF

Abstract

The productivity of the reno potato in the country is below the known potential due to several biotic and abiotic factors. Mineral nutrition, in particular the availability of phosphorus (P), is extremely decisive in the productive performance of the reno potato crop; as it is associated with the tuberization process. Therefore, this study tested five doses of P (0, 80, 100, 120 and 160 kg.ha -1 ) in four replications under the conditions of the experimental field of FAEF to examine the influence of different doses of P on the yield of the reno potato variety Mondial. The analysis of variance of the response of the Mondial variety to phosphate fertilization revealed that P influenced the number of stems formed per plant, plant height, canopy diameter and crop yield, where the dose of 160 kg.ha -1 of P had the greatest influence on these variables compared to the other doses (p < 0.05). The number of stems, plant height, canopy diameter and crop yield ranged from 2-4, 29-65 cm, 43-59 cm and 12 to 21 ton.ha -1 , respectively, where these variables were positively correlated with each other (p < 0.05). Also, regression analysis showed that these variables were strongly associated with P doses (r 2 = 0.78 to 0.90). There were no significant differences in the yield obtained at the different P doses; therefore, phosphate fertilization is recommended at a range of 80 to 100 kg.ha -1 of P (17 to 18 ton.ha -1 ). The severity index of late blight (1-29%), dry rot (4 to 26%) and root-knot nematodes (Pi/Pf = 500/460) suggested that P doses had no influence on the attack of the crop by these diseases. (TRADUÇAO NOSSA)