Molecular diversity and phylogeny in geographical collection of chickpea (Cicer sp.) accessions

Abstract

Chickpea (Cicer arietinum L.) is the third most important pulse crop in the world and India is the largest producer of this crop. Nevertheless, its yield in India is low (0.7 tone per hectare (t/ha)) as compared to Australia, Egypt, Israel and Italy (1 t/ha) (FAOSTAT 2008, http://faostat.fao.org/). There has been a significant change in the scenario of chickpea cultivation in India during the past three decades. The expansion of irrigated agriculture in northern India has led to displacement of chickpea with wheat in large area. As a result, the area under chickpea reduced from 3.2 million ha to 1.0 million ha in northern and northwestern India (Punjab, Haryana and Uttar Pradesh), while it increased from 2.6 million ha to 4.3 million ha in central and southern India (Madhya Pradesh, Maharashtra, Andhra Pradesh and Karnataka) from 1985 to 1990. Because of relatively warm environments in central and southern India, the crop is challenged by Fusarium wilt, a major yield reducing disease, while in northwestern India, due to cooler environments, the crop is exposed to a severe foliar disease Ascochyta blight. The narrow genetic base among cultivated chickpea accessions is limiting genetic improvement of chickpea through breeding efforts. Understanding the extent of natural variation among cultivated chickpea and wild accessions at molecular level is essential to develop prebreeding and breeding strategies for chickpea. Until recently, the low intraspecific and inter-specific polymorphism in chickpea accessions detected by molecular markers and the scarcity of codominant DNA-based markers were serious constraints that hindered the preparation of dense molecular genetic maps or tagging of important traits in chickpea. However, recent studies using STMS markers reveal fairly high levels of