Association of AFLP and SCAR markers with common leafspot resistance in autotetraploid alfalfa (Medicago sativa)

Abstract

ABSTRACT. To identify amplified fragment length polymorphism (AFLP) markers associated with resistance or susceptibility of alfalfa to common leafspot (CLS) caused by the fungus Pseudopeziza medicaginis (Dermateaceae), bulked segregant analysis was conducted based on an F 1(M × M) population of 93 plants and a BC 1 S population of 91 plants. Three AFLP markers, ACTCAA R206 , TAGCAC R185 , and GGACTA S264 , were found to be associated with CLS resistance or susceptibility. All three markers were found at significantly different frequencies (71.9, 80.3 and 91.8%) compared to resistant or susceptible plants in the original population. Subsequently, these three AFLP markers were converted into three SCAR markers, ACTCAA R136 , TAGCAC R128 and GGACTA S254 , which are easier to employ in breeding programs. The three SCAR markers were used in a randomly selected population with 50% resistance; the probability of finding one resistant plant was increased to 67.3, 66.7 and 90.0% with markers ACTCAA R136 , TAGCAC R128 and GGACTA S254 , independently. If two of the SCAR markers were used simultaneously, the probability would be higher than 89%. The three SCAR markers identified in this study would be applicable for selection for CLS resistance in alfalfa breeding programs. Moreover, the genetic analysis indicated that CLS resistance in alfalfa is conferred by a single dominant gene.

SCAR Marker for Identification and Discrimination of Commiphora wightii and C. myrrha

“…SCAR markers have been also developed for breeding programs of crops like Rice [ 81 ], Citrus tristeza [ 82 ], Brassica napus L. [ 83 ], Grapevine [ 84 ], Wheat [ 85 ], Buckwheat [ 86 ], Grape [ 87 ], Barley [ 88 ], Atractylodes japonica and A. macrocephala [ 89 ], Diplocarpon rosae [ 90 ], Puccinia coronata [ 91 ], Puccinia striiformis [ 92 ], Thinopyrum elongatum [ 93 ], Liriope and Ophiopogon [ 94 ], Medicago sativa [ 95 ], Triticum turgidum [ 96 ], and Miscanthus sacchariflorus [ 97 ].…”