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Red-mottled common bean (Phaseolus vulgaris L.) germplasm lines PR9745-232 (Reg. no. GP-242, PI 639721) and RMC-3 (Reg. no. GP-243, PI 639868) with resistance to Bean golden yellow mosaic virus (BGYMV), a whitefly [Bemisisa tabaci (Gennadius)]-transmitted begomovirus, were developed and released cooperatively by the Agricultural Experiment Station of the University of Puerto Rico (AES-UPR) and the International Center for Tropical Agriculture (CIAT).
PR9745-232 was derived from the double-cross 'Indeterminate Jamaica Red' (PI 163122)/PR9180-25C//DOR 482/ PR9231-94. Indeterminate Jamaica Red is a pink-striped landrace with a Type III growth habit and heat tolerance. PR9180-25C is a red-mottled breeding line selected for heat tolerance and resistance to common bacterial blight [caused by Xanthomonas axonopodis pv. phaseoli (Smith) Vauterin et al. (syn. = X. campestris pv. phaseoli)]. DOR 482, released in Central America as 'Don Silvio', is a small (<25 g 100-seed weight^sup -1^) red breeding line with the recessive bgm-1 allele, first identified in pinto bean breeding line A 429 (Blair and Beaver, 1993), for resistance to leaf yellowing and chlorosis caused by BGYMV (Velez et al., 1998). DOR 482 also has the I allele for resistance to BCMV. Furthermore, Molina-Castañeda and Beaver (1998) found DOR 482 to have the dominant Bgp-1 allele for resistance to pod deformation induced by BGYMV. PR9231-94 is a high-yielding line with commercially acceptable red-mottled seed. The double-cross was made at the Isabela, Puerto Rico, Substation in October 1994. The F^sub 1^ was planted at Isabela in January 1995 and individual plants were selected based on seed and plant type from an F^sub 2^ nursery planted at the same location in October 1995. Pedigree selection for agronomic traits and disease resistance was used from the F^sub 3^ to F^sub 5^, whereupon seed from the F^sub 4:5^ plant-to-progeny row identified as PR9745-232 was bulked. The breeding line was planted at the Isabela Substation during the summer of 1998 to screen for heat tolerance and resistance to BGYMV.
On a 1-to-9 disease rating scale in which 1 is resistant and 9 is highly susceptible (CIAT, 1987) PR9745-232 had an average BGYMV score of 1.0 in the Dominican Republic in 1998, 1999, and 2000, and in Haiti in 1999 (PROFRIJOL, 2001). However, under severe pressure, a few plants of PR9745-232 developed BGYMV symptoms at Bastidas, Dominican...