Duration and rate of tuberization and fresh weight of aerial parts of potato plants

Abstract

This work was to analyze the duration and rate of tuberization, number of tubers, top weight and flowering through the developmental stages of the potato (Solanum tuberosum L., cv. Baronesa) at Pelotas, RS, Brazil. The plant was harvested at seven days intervals after emergence, through the cycle. Ortogonal polynomial analyzis of the fresh weight of the tubers and canopy in relation to time was employed to determine the best adjusted equation. The tuberization rate was obtained by the first derivative of the equation adjusted. The cultivar showed that the tuberization started at 23 days. The maximum tuberization was gotten at 83 days after emergence with 2,890.6 g/m² and maximum rate was recorded at 36 with 64,4 g/m² /day. The maximum of the canopy weight was reached at 49 days and decreased rapidly. The average number of tubers per plant showed linear function in relation to time, while the canopy weight presented a quadratic function. The tubers weight showed a cubic function. There was no correlation between canopy weight and/or number of the tubers. However, there was positive correlation between weight and number.