Calidad de semillas de arroz producidas por semillas nacionales C.A.-SENACA em El Ecuador

Abstract

Rice represents in Ecuador a primary food in the daily diet; this is the reason because its planting in recent years has increased considerably. The increase is higher than the use of certified seed rice which represents one fifth of the total area dedicated to rice production. Results of a better production are due to the introduction of varieties such as F-50 and SGO-667; these seeds have high yield parameters and are distributed with maximum quality standards in the Ecuadorian seed rice market. This work evaluated the physiological quality of seed rice produced and distributed by SENACA. The experimental data were obtained from rice production for the years 2005 to 2007 for germination and vigor parameters. Data were analyzed using polynomial regression for both parameters. Results showed that F-50 got similar percentage values ≥ 90% for germination and vigor during the three years of the study at 0 days while at 180 days the value decreased 3% in average. Both data fitted quadratic regressions with an average confidence of 75% except for 2005 where regressions were not significant neither for germination nor vigor. In the other hand for SGO-667 rice variety the percentage for germination and vigor were ≥ 81% in average for both parameters at 0 days whereas at 180 days the value increased 3% in average in 2006. While for 2007 data showed patterns of increase and decrease for germination and vigor, data fitted cubic regression perfectly. These patterns in the variety could be due to the seed shown dormancy in the two years of the study. It is highly recommended to consider a more sensitive test of vigor (hidric stress and tetrazolium biochemical test) due similar values between vigor and germination and to implement seed quality sampling every 60 days.