Cicer turcicum: A New Cicer Species and Its Potential to Improve Chickpea

Abstract

Genetic resources of the genus <i>Cicer</i> L. are not only limited when compared to other important food legumes and major cereal crops but also, they include several endemic species with endangered status based on the criteria of the International Union for Conservation of Nature. The chief threats to endemic and endangered <i>Cicer</i> species are over-grazing and habitat change in their natural environments driven by climate changes. During a collection mission in east and south-east Anatolia (Turkey), a new <i>Cicer</i> species was discovered, proposed here as <i>C. turcicum</i> Toker, Berger & Gokturk. Here, we describe the morphological characteristics, images, and ecology of the species, and present preliminary evidence of its potential utility for chickpea improvement. <i>C. turcicum</i> is an annual species, endemic to southeast Anatolia and to date has only been located in a single population distant from any other known annual <i>Cicer</i> species. It belongs to section <i>Cicer</i> M. Pop. of the subgenus <i>Pseudononis</i> M. Pop. of the genus <i>Cicer</i> L. (Fabaceae) and on the basis of internal transcribed spacer (ITS) sequence similarity appears to be a sister species of <i>C. reticulatum</i> Ladiz. and <i>C. echinospermum</i> P.H. Davis, both of which are inter-fertile with domestic chickpea (<i>C. arietinum</i> L.). With the addition of <i>C. turcicum</i>, the genus <i>Cicer</i> now comprises 10 annual and 36 perennial species. As a preliminary evaluation of its potential for chickpea improvement two accessions of <i>C. turcicum</i> were field screened for reproductive heat tolerance and seeds were tested for bruchid resistance alongside a representative group of wild and domestic annual <i>Cicer</i> species. <i>C. turcicum</i> expressed the highest heat tolerance and similar bruchid resistance as <i>C. judaicum</i> Boiss. and <i>C. pinnatifidum</i> Juab. & Spach, neither of which are in the primary genepool of domestic chickpea. Given that <i>C. arietinum</i> and <i>C. reticulatum</i> returned the lowest and the second lowest tolerance and resistance scores, <i>C. turcicum</i> may hold much potential for chickpea improvement if its close relatedness supports interspecific hybridization with the cultigen. Crossing experiments are currently underway to explore this question.