Assessment of Methods Used in Testing Preharvest Sprouting Resistance in Hulless Barley*

Abstract

Due to the great decrease in quantity and quality of grain caused by preharvest sprouting(PHS),breeding of the cultivars with high PHS resistance has became an urgent task.There are abundance hulless barley resources in China. However,few investigations have been made so far on their PHS resistance.In order to lay a foundation for breeding of resistance to PHS,evaluation index systems are needed.In this study,we evaluated the differences in sprouting index(SI), sprouting rate(SR),germination index(GI)andα-amylase activity(AA)of 34 accessions of hulless barley obtained from the Qinghai-Tibetan Plateau,which were cultivated in Maerkang and Chengdu,China,respectively.These PHS sprouting parameters were significantly affected by accession×location,and they had correlation among each others.GI was the most reliable parameter because of its low CV value,good repeatability and simple operation.SI could assist in differentiation of the accessions of similar dormancy or overall evaluation of the resistance.AA was bad in repeatability and more difficult to be tested,and it,therefore,not appropriate for breeding,evaluating and screening PHS resistant materials.Besides,since PHS resistance of hulless barley was greatly influenced by its growth environment,its influence factors and variations under different cultivation conditions should be specially considered.Fig 1,Tab 4,Ref 24