Evaluation Of Seed Purity Testing Technologies For Maize

Maize is one of the main staple and feed crops in China. Demand of ample maize seed withgood quality has enlarged recently. Evaluation of the seed purity is imperative forimproving seed trade, increasing yield production and obtaining plant variety protection.Variety purity may show differences to the real genetic performance when using differenttesting methods. Thus, a standardized seed testing should be established to get predictableand consistent varietal purity. This paper describes comparison of consistency, reliability,and applicability and cost-effectiveness of three testing methods that have been widely usedin recent years for maize seed testing in Xian-Fan Zhen-Tai Agricultural DevelopmentCompany Ltd. The seed purity of more than one hundred and thirty samples of six maizevarieties was assayed by using the three testing methods: storage proteins electrophoresis,isozyme isoelectric focusing in acrylamide and examination at field plots. Some importantpoints can be concluded from analyses as spearman order rank correlation on the seedpurity data as follows:First, there were deviations of the real performances to those purities obtained from out or in laboratory testing, even from the examination at field plot that is a routine way. Second, the seed globulin and isozyme electrophoresis, both with characteristics of rapid, cost-effective, devoid of environmental effect and speed, showed consistent purity; while the field-testing gave a higher degree of purity on the high side of cost than that in-lab approaches. Third, a good consistent purity was observed in the field plot and seed globulin testing, whereas inconsistency between field-testing and isozyme process. The last point is that seed globulin electrophoresis be a practical method apt to seed purity testing for maize. Conclusively, the results in this study provide an important practical basis to improve andstandardize the seed testing system in maize.