Harvest period and quality of rubber tree seed.

Abstract

This work was made in a rubber plantation of clone RRIM 600, seven years old, in Colina, SP, Brazil. Its objective was to study the time of harvest and quality of rubber seeds (Hevea braslliensis Muell. Arg.), during the years of 1986 and 1987. The harvest was made with weekly intervals for both years, after the beginning of the seed fullup and at its and. The following parameters were determined: moisture content of seeds, number of seeds per plant, weight of seeds per plant, seed individual weight, number of seeds per kg, 100 seeds weight, emergence percentage and emergence speed. The results showed that 1. the moisture content of seeds decreased during the harvest period, for both years; 2. production and quality of seeds were variable in function of the harvest period, in the same year and year by year, 3. in both years, the highest values of seed weight and the percentage of seed emergence were obtained in a period referential to the peak of seeds fullup; and 4. the physiological quality of seeds harvested in 1986 was superior to the quality of those harvested-in 1987.