Industrial Crops and Products 97 (2017) 639–648 Contents lists available at ScienceDirect Industrial Crops and Products jo ur nal home p age: www.elsevier.com/locate/indcrop Role of conventional and biotechnological approaches for genetic improvement of cluster bean Sushil Kumar a,∗ , Arpan R. Modi a , Mithil J. Parekh a , Hans R. Mahla b , Ramavtar Sharma b , Ranbir S. Fougat a , Devvart Yadav c , Neelam R. Yadav d , Ghanshyam B. Patil a a Department of Agricultural Biotechnology, Anand Agricultural University (AAU), Anand, 388 110, India b Division of Plant Improvement, Propagation and Pest Management, Central Arid Zone Research Institute (CAZRI), Jodhpur, 342 003, India c Department of Genetics and Plant Breeding, CCS Haryana Agricultural University (CCSHAU), Hisar, 125 004, India d Department of Biotechnology and Molecular Biology, CCS Haryana Agricultural University (CCSHAU), Hisar, 125 004, India a r t i c l e i n f o Article history: Received 12 May 2016 Received in revised form 3 January 2017 Accepted 7 January 2017 Keywords: Breeding Biotechnology Cluster bean Diversity Guar Molecular markers a b s t r a c t Cluster bean [Cyamopsis tetragonoloba (L.) Taub. (Syn. C. psoraliodes)], commonly known as guar and an important crop from family Leguminaceae, is grown under resource constrained situations for use as seed, vegetable and forage in arid and semi-arid regions. The seed of this drought-resilient legume contains galactomannan polysaccharide, used in wide range of industries, which has made this orphan crop a high-valued cash crop. Cluster bean shows limited variability for morphological and agronomic traits. Narrow genetic base of cultivated cluster bean varieties and yield losses due to both biotic and abiotic stresses has hampered the intensive breeding efforts in cluster bean. Conventional breeding methods viz. induced mutations, wide-hybridization and induce male sterility have been employed to broaden the limited genetic base and for genetic improvement of cluster bean. Due to its pivotal role in rainfed agriculture, research efforts using biotechnological interventions like molecular markers, tissue culture and transformation have been initiated to boost the varietal improvement but development of these tools are still at early stage in cluster bean. This article attempts to summarize and discuss the recent progress made in mutation breeding, distant hybridization, DNA marker studies, development of in-vitro propagation system and genetic transformation protocols. © 2017 Elsevier B.V. All rights reserved. Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639 2. Genetic improvement of cluster bean through conventional approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .640 2.1. Genetic diversity and germplasm resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 640 2.2. Induced variation through mutation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641 2.3. Wide crosses and distant hybridization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 642 2.4. Male sterility and heterosis breeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 642 3. Role of biotechnology in cluster bean improvement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 642 3.1. Molecular markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 642 3.2. Tissue culture, regeneration protocols and genetic transformation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 643 4. Conclusion and future prospects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 646 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 646 ∗ Corresponding author. E-mail addresses: sushil254386@gmail.com, sushil254386@yahoo.com (S. Kumar). 1. Introduction Globally cluster bean/guar (Cyamopsis tetragonoloba, 2n = 14), a member of family Leguminaceae, is an important crop of arid and semi-arid regions (Kumar et al., 2015). It is believed that geographic http://dx.doi.org/10.1016/j.indcrop.2017.01.008 0926-6690/© 2017 Elsevier B.V. All rights reserved.