However, this variability cannot be exploited in a direct way because of ploidy or genome differences among the species [12] and [13]. In order to overcome the genetic bottleneck of restricted gene flow, the development of synthetic

selleck compound amphidiploids is an effective option to diversify the cultivated gene pool. To date, several synthetics have been developed by using different diploid species through colchicine-mediated genome duplication [14], [15], [16] and [17]. These highly diverse synthetics provide an opportunity for introgression of some important traits to cultivated germplasm. However, limited success has been achieved so far in using the wild species as genetic resources for the development of resistant cultivars. Nevertheless, release of an Indian variety (GPBD 4) containing resistance to foliar diseases in chromosome segments from Arachis cardenasii is an example of success. GPBD 4 is an improved variety developed as a second cycle derivative of an interspecific cross and is grown in several states in India for its desirable traits such as foliar disease resistance and high yield. Because of its high levels of resistance, A. cardenasii Krapov. & W. C. Greg. is the most widely used wild species in groundnut breeding

programs aimed at improving foliar disease resistance. However, it is always better to look for alternative sources of resistance in order to diversify the cultivated

gene pool [4]. Realizing the PLX4032 great potential of synthetic amphidiploids for enhancing the richness of the Phenylethanolamine N-methyltransferase gene pool, this study was undertaken to broaden the genetic base of cultivated groundnut by introgressing resistance genes into five cultivated genotypes. We report the development of diverse genetic materials in groundnut with potential for several genetic and breeding applications. Synthetic amphidiploids ISATGR 278-18 [ICG 8138 (Arachis duranesis Kaprov. & W. C. Greg.) × ICG 13160 (Arachis batizocoi Kaprov. & W. C. Greg.)] and ISATGR 5B [ICG 8960 (Arachis magna Kaprov., W. C. Greg. & C. E. Simpson) × ICG 8209 (A. batizocoi Kaprov. & W. C. Greg.)] with 2n = 2x = 40 were generated at ICRISAT (Hyderabad, India). Seeds from these amphidiploids were planted in a glasshouse at the University of Agricultural Sciences (UAS), Dharwad, India. Both amphidiploids were used to generate backcross populations with five elite varieties/genotypes, namely ICGV 91114, ICGS 76, ICGV 91278, JL 24, and DH 86 after making two backcrosses. Flowers of cultivated genotypes were emasculated a day before pollination. Cross pollination was carried out before 10:00 a.m. on the following day by using the synthetic amphidiploids as pollen parents. Cotton swabs impregnated with gibberellic acid (GA3) (0.5 mL; 75 mg L− 1) were wrapped around the base of pollinated pistils.