Avaliação da qualidade fisiológica e caracterização bioquímica de sementes de feijão-caupi

Abstract

Cowpea is a legume of high socioeconomic importance, especially in tropical and subtropical regions, due to its adaptability, low cultivation cost and high nutritional value. The use of quality seeds is essential for crop establishment and productivity, and this quality is assessed through physiological and biochemical tests. The present study aimed to evaluate the physiological quality of different lots of cowpea seeds through germination and vigor analyses and to characterize the starch and carbohydrate contents of the seeds. Nine lots of cowpea seeds were analyzed and subjected to germination, characterization, and vigor tests (first count, seedling length and dry mass, emergence speed index and electrical conductivity). The determination of starch and carbohydrate contents was performed by colorimetric methods using a spectrophotometer. The results indicated significant differences between the lots for the physiological variables. Vigor tests, especially the first count and electrical conductivity, were efficient in differentiating lots with greater physiological potential. However, starch and carbohydrate contents did not show significant variation between lots, but a positive correlation was observed between starch and carbohydrate contents and shoot length, indicating that seeds with greater energy reserves result in more developed seedlings. It was concluded that the lots showed statistical differences in the variables of vigor, germination and characterization, however, carbohydrate characterization did not differ statistically between lots.