Comparative Studies on Cotton Seed Germinability with Tetrazolium Viability Test and X-ray Contrast Methods

Abstract

Seed viability testing provides valuableinformation for assessing seed lot germinability. However,most testing methods require destruction of seed prior totest. Because the dissected seeds for viability test cannotbe used further evaluation, the nondestructively X-rayphotography technique that can be applied for the evaluationof seed quality has been developed. In order to know thevalidity and accuracy of X-ray photography technique inseed evaluation test that conducted to remove the abnormalseed from a seed lot, we have compared the results fromtetrazolium viability test, germination test and X-ray contrastmethod in cotton. Metallic salts treatment increased theefficiency of X-ray photographic method by enhancing thepenetration of X-ray in abnormal or damaged seeds ratherthan normal seeds that have strong and well-organizedtissues in seed. Cotton seeds presoaked for 16 hr indistilled water followed by soaking into metallic saltsolution (5% NaI in water) for 60 min were easily classifiedseeds into dead seed and viable seed based on the radiographyimages obtained by X-ray radiation. We concludedthat soft X-ray photography was reliable to find out thevarious defective characters due to heat and mechanicaldamage of seeds.