Influence of seed polymorphism on physical, physiological and biochemical seed qualitycharacters of endangered medicinal tree Bael(Aegle marmelos (l.) corr.)

Abstract

Bael is a medicinal tree with multipurpose utility propagated through seeds. Bulk seeds of Bael exhibit polymorphism in seed characteristics. Hence, a study was undertaken to evaluate the influence of seed polymorphism on physical, physiological and biochemical seed quality characters. Polymorphic seeds based on size were separated by size grading the seeds using round perforated metal sieves of sizes 6.4, 6.0 and 5.5 mm retained and 5.5 mm passed (hole width), and the recovery of seeds retained on these sieves were 40, 23, 31 and 6% respectively. The physiological seed quality characters measured in terms of germination was higher with 6.4 mm sieve retained seeds (77%) and was followed by seeds retained on 6.0 mm (68%), 5.5 mm (55%) sieve; the seeds passed through 5.5 mm sieve registered only 41% germination while the germination recorded with bulk seeds was 63%. The seedling vigour measured through root length (11.3 cm), shoot length (9.3 cm), dry matter production (366 mg) and (1586), vigor index 2 (870) and vigour index 3 (28182) values were also higher in large seeds retained on 6.4 mm sized sieve. The biochemical characters measured as α– amylase activity (5.2 cm) and dehydrogenase (0.193) were higher in larger seeds including seed protein (17.4%) and oil content (38.1%). The study thus expressed a linear relationship between seed size and physical, physiological and biochemical seed quality characters and necessitates homogenizing the seed lot based on size. Key words: Bael, seed polymorphism, seed germination, oil content, α–amylase, dehydrogenase activity.