Diversity of seed protein among the Australian narrow-leafed lupin (Lupinus angustifolius L.) cultivars

Narrow-leafed lupin (NLL) is one of the major legume crops in Australian farming systems which is largely used as animal feed. Several modern cultivars have been developed through breeding making NLL feasible for use as human food. Significant health benefits have been recognised for NLL. The current study characterised protein polymorphism among 25 Australian cultivars through mass spectrometry (MALDI-TOF) with the aim of developing molecular breeding strategies to improve protein quality and content. A total of 364 seed protein mass peaks were clearly identified by MALDI-TOF and 50 protein mass peaks were cultivar specific. In addition, 9 protein mass peaks were found present in all cultivars and 61 protein mass peaks present in 2-3 cultivars only. Phylogenic analysis based on the protein profile categorised the cultivars into 2 major groups, which are broadly supported by pedigree information. The low proportion (2.4%) of common protein mass peaks among the cultivars suggested a high level of diversity in seed protein of NLL.