PRODUCTION AND COST OF FRUITS AND SEEDS AMONG LIFE FORMS

This study deals with the proportions of seeds, ovules and flowers-fruits aborted, and seeds formed per ovule per inflorescence, related to the weight and number (seed, ovule, flower and fruit) of reproductive structures among five life forms. The study shows that ovule abortion, flower-fruit abortion and seed per ovule per infructescence were significantly higher in trees than in annual and perennial herbs. The correlations between the characteristics of reproductive structures and the abortion levels revealed an increase of ovules aborted with the weight of fruits and seeds, the number of seeds per fruit and flower, fruit weight/flower weight ratio and seed per fruit weight/flower weight ratio from annual herbs to trees. The percentage of seeds per ovule per infructescence decreased with the increase of fruit weight, fruit weight/flower weight ratio, percentage of ovules aborted and flower-fruit aborted. These results suggest that the increase in the energetic investment in fruits and seeds can result in an increase in the number of ovules and fruits aborted from herbs to trees.