Delmonte Roboredo

Assess the growth and physiological quality of seeds of rice cultivars grown in alternatives to the renewal of pasture

The objective of this study was to assess the growth and physiological quality of seeds of rice cultivars grown in alternative systems for pasture renewal. The study was conducted in the municipality of Alta Floresta-MT in the 2006/07growing season. The experimental design was in randomized blocks with 4 replications in a 2x8 factorial scheme, consisting of the combination of two rice cultivars (BRS Primavera and BEST 2000) and eight options for renewal, and four low concentrations of the cyhalofop butil herbicide (180 g L-1) (0, 0.40, 0.80 and 1.2 L ha-1) and brachiaria sown by hand and incorporated 10 and 20 days after rice emergence. In treatments in which brachiaria received low herbicide concentrations, the grass was sown together with the rice. The following plant characteristics were evaluated: plant height, length and diameter of between node and leaf area index. The tests on physiological quality of seed, germination, first count, speed of germination index, electrical conductivity and accelerated aging were carried out. The BRS Primavera cultivar produced seed of better quality, all the alternatives were shown to be viable for seed and the region of Alta Floresta was shown to be suitable for rice seed production.