Seed quality assessment

Abstract

Growers expect high-quality, genetically pure seed. As a result, seed companies maintain quality control programmes that monitor seed from harvest to purchase. An array of ‘traditional’ seed quality tests, including mechanical tests and tests of genetic purity, seed germination and vigour, and seed health tests, is used, and seed quality assessment techniques continue to evolve. Advances in molecular genetics are allowing the release of new varieties differing essentially in one gene. New molecular biology approaches offer the potential to identify these subtle genetic differences. Advances in seed enhancements, such as pelleting, priming and pregermination, require increased scrutiny of seed quality before and after the enhancement process. New developments in computer imaging for improved purity and germination/vigour analyses are being developed. These novel approaches to seed quality assessment become important as new genetic improvements are conveyed in the seed at increased cost to the grower.

Physiological response of cowpea seeds to salinity stress

“…This might have occurred due a possible priming effect caused by low NaCl concentration. Priming can improve seed performance, due to its effect in repairing damaged membranes and organelles, resulting in a faster seed emergence and higher seedling growth (McDonald, 1998).…”

Imagens digitalizadas na interpretação do teste de tetrazólio em sementes de Brachiaria brizantha

“…Existe demanda por testes rápidos que proporcionem agilidade e segurança para comercialização ou armazenamento de sementes de espécies que exigem períodos relativamente longos para completar os testes de germinação (McDonald, 1998;Marcos Filho, 2005;Custódio, 2005). A indicação das Regras para Análise de Sementes é de, até, 21 dias para complementação do teste de germinação de Brachiaria brizantha (Brasil, 2009).…”

Amorçage et séparation des graines d'épinette noire (Picea mariana (Mill.) B.S.P.) :

“…En permettant l'initiation des activités métaboliques dans les graines, l'amorçage occasionne une hausse de la vitesse, de l'uniformité et du potentiel de germination des semences d'une multitude d'espèces végétales (Bradford, 1986;Hill etal., 1989;Rowse, 1996;McDonald, 1998), incluant les conifères (Bourgeois et Malek, 1991;Downie et Bergsten, 1991a;Bergsten, 1993;Downie et al, 1993;Brand et Riov, 1999). Les effets rapportés sont toutefois très variables entre les espèces, les variétés, les lots de graines et les conditions de traitement.…”