Page 1 of 6 Critical review Licensee OA Publishing London 2014. Creative Commons Attribution License (CC-BY) For citation purposes: Ghosh G, Purohit A, Chaudhuri RK, Chakraborti D. Advances in genetic transformation of important pulse crop pigeonpea. OA Biotechnology 2014 Mar 12;3(1):5. Competng interests: none declared. Confict of interests: none declared. All authors contributed to concepton and design, manuscript preparaton, read and approved the fnal manuscript. All authors abide by the Associaton for Medical Ethics (AME) ethical rules of disclosure. * Corresponding author Email: dipankar_12@yahoo.co.in 1 Post Graduate Department of Biotechnology, St. Xavier’s College (Autonomous), 30, Park Street, Kolkata 700016, India 2 Department of Botany, Bethune College, 181, Bidhan Sarani, Kolkata 700006, India Advances in genetic transformation of important pulse crop pigeonpea G Ghosh 1 , A Purohit 1 , RK Chaudhuri 2 , D Chakraborti 1 * Globally, pigeonpea is cultivated on 4.92 million hectares (m ha) with an annual production of 3.65 metric tons and productivity of 898 kg/ha 2 . India contributes to more than 80% of the global production of pigeon- pea, where it is the second important food legume. But over the past sever- al decades, the production of pigeon- pea has been maimed by several bi- otic and abiotic factors. Endeavours to redress these problems have met with limited success. Among many insect pests, the pod borer Helicover- pa armigera causes significant dam- age to this crop. It is also susceptible to the wilt disease caused by Fusar- ium udum, particularly in the humid regions. Among abiotic stresses, wa- ter logging, cold sensitivity, terminal drought and salinity stresses inflict losses in the production during vari- ous stages of the development. As pigeonpea is a self-pollinated plant with narrow genetic base, conven- tional breeding had no conspicuous effects on the genetic improvement. Thus, genetic transformation plays an important role in the incorpora- tion of agronomically convenient characters. The aim of this review was to discuss advances in genetic transformation of important pulse crop pigeonpea. Discussion The authors have referenced some of their own studies in this review. The protocols of these studies have been approved by the relevant ethics com- mittees related to the institution in which they were performed. Genetic transformation The capability of integrating alien DNA into plants has been one of the Abstract Introduction Pigeonpea is one of the major grain legumes of tropics and subtropics, covering vast regions of developing countries from Africa, Asia to Latin America. India accounts for 80% of global production, where it is the second most important food legume. As they are grown in harsh environ- ments and exposed to a variety of biotic and abiotic stresses, their pro- ductivity has not increased conspicu- ously for the last 50 years. Therefore, it is of utmost importance to aug- ment the productivity of pigeonpea to cope with the increased threat of population boom. To combat these issues, various methods of conven- tional breeding have been deployed, albeit with little progress. This is mainly due to the absence of desir- able traits in the primary gene pool. In this aspect, genetic transforma- tion can be considered as an integral tool in breeding strategies, as it can overcome the constraints laid down by sexual incompatibility. Range of applications, such as microprojectile bombardment, electroporation and Agrobacterium-mediated gene trans- fer, are available to transfer desirable foreign genes into this plant species. Several attempts have been made to develop reliable regeneration meth- ods suitable for transformation in pigeonpea. In this review, we will summarise various gene delivery methods applied in pigeonpea for its improvements. Subsequent molecu- lar analyses of the transgenic pigeon- pea plants will also be discussed. Additionally, we will focus on the fu- ture prospects of transgenic research of this important food legume. Conclusion The full realisation of the plant bio- technology revolution depends on successful and innovative research, as well as on favourable regulatory guide- lines and public acceptance. Thus, all the strategies discussed in the present review will definitely contribute to bi- otechnological breeding programmes of pigeonpea for its improvement. Introduction Pigeonpea [Cajanus cajan (L.) Mill- sp.] is a short-lived perennial shrub, which is traditionally cultivated as an annual crop in the semi-arid tropics representing the majority of the de- veloping nations. This environment is home to the poor and one-sixth of the world’s population 1 . It is an im- portant grain legume richer in pro- teins (21%) than cereal grains and is a source for a significant amount of dietary protein requirements. Dry split seeds of pigeonpea are used widely for dahl preparation for hu- man consumption. Protein contain- ing leaves are used as fodder and dry crushed seed as animal feed. Ad- vances in biotechnology and genetics have enabled us to explore cereals such as rice, wheat, barley and maize; whereas among the grain legumes, only soybean and peanut have been scrutinised in terms of biotechnolog- ical improvements. Pigeonpea is one of the major recalcitrant pulses com- pared with its legume counterparts. Agro- & Food Biotechnology