Rapid Identification of Citrus Varieties Using DUS Testing Combined with InDel Marker
Variety identification is a prerequisite for plant variety protection.DUS(distinctness,uniformity,and stability)testing based on phenotypic traits is an internationally recognized and legally valid method.Nev-ertheless,conducting the complete DUS testing for fruit crops are usually faced with challenges such as long period and dilemma in selecting similar varieties.Although molecular markers can accurately reveal the genetic characteristics,it is difficult to identify the varieties derived from bud mutation,back crossing and selection in high generation segregation.According to the description in'Guide in DUS testing for new plant variety Citrus(NY/T 2435-2013)',we evaluated the five testing materials(unknown varieties)with 101 traits,found that they did not show visible difference.In a comparison with the trait data of 1,900 citrus germplasms in National Citrus Germplasm Repository(Chongqing,China),the testing materials showed the differences in one-code discrepancy of one trait(fruit weight)with Kinnow LS mandarin(Citrus reticulata Blanco),and one to two-code discrepancies of four traits(fruit weight,peel colour,oil gland status,acidity)with 091 Seedless Orah mandarin(C.reticulata Blanco),indicating that 091 Seedless Orah mandarin and KinnowLS mandarin were the similar varieties of those testing materials.Furthermore,33 agarose gel electrophoresis-resolved InDel markers were applied to test those materials.There were no polymorphic discrepancies among the five samples and Kinnow LS mandarin,but the testing samples showed 12 different loci compared to 091 Seedless Orah mandarin.Taken together,the five samples were identified as Kinnow LS mandarin.Trait evaluation com-bined with InDel marker detection is an effective solution for the quick and precise identification of unknown citrus varieties.
万方数据
维普
