ISSN: 2471-9315
Junjie Zhang, Wenfeng Chen, Raghvendra Pratap Singh, Yimin Shang
Chickpea, Cicer arietinum L., is an inexpensive, important, old and worldwide pulse crop consumed widely, with two distinct cultivated types of cultivar Desi and Kabuli. Chickpea is grown in over 50 countries across the Indian subcontinent, North Africa, the Middle East, southern Europe, the Americas, Australia and China. It is a good source of carbohydrates and protein, together constituting about 80% of the total dry seed mass. Chickpea consumption is reported to have several positive physiological and health benefits and might reduce the risk of chronic diseases and optimize health. Therefore, chickpeas could potentially be considered as a ‘functional food’ in addition to their accepted role of providing proteins and fiber. During the past two decades, rhizobial diversity associated with chickpea has been studied extensively in several countries, in Europe, Asia, and Oceania to elaborate the impact on the sustainable qualitative and quantitative yield of chickpea. To date, Mesorhizobium ciceri, M. mediterraneum, M. muleiense and M. wenxiniae have been described to accommodate the rhizobial strains originally isolated from chickpea root nodules. In addition, several Mesorhizobium species, i.e., M. amorphae, M. loti, M. tianshanense, M. oportunistum, M. abyssinicae and M. shonense were reported as additional potential symbionts of chickpea after lateral gene transfer acquisition of symbiovar ciceri gene set. M. ciceri and M. mediterraneum are ubiquitous in most of the countries and widely studied in the Spain, Portugal, Morocco, Tunisia and India; however, none of them were found M. muleiense and M. wenxiniae except in Xinjiang and Gansu Provinces Northwest China. The geographic distribution of the chickpea varieties suggested that during the introduction of chickpea from one region to another, the seeds might contain some chickpea rhizobia during the harvest or it had been inoculated with chickpea rhizobia after introduction. Chickpea rhizobial inoculation could improve the nitrogen fixation and plant growth and finally increase the yield and nutrient content of chickpea seed.