Inheritance of Resistance to Blight in Pigeonpeas

Untitled

“…All six crosses segregated 3:1 resistant:susceptible in the F 2 populations and 1:1 in BC 1 P 1 (Table 1). Sharma et al (1982) reported the monogenic dominant control of resistance to P 2 isolate of PB but, one of their resistant parents (Pant A3) was susceptible to the P 3 isolate of PB in the present investigation. Therefore, the resistance gene in KPBR 80-2-1 must be different from that reported earlier (Pd 1 ) and so here it is designated as Pd 3 .…”

“…At present, no early maturing cultivar is known to have resistance/tolerance to this disease. The possibility of occurrence of more than one race(s) of PB has been indicated Sharma et al (1982) among others. Subsequently the presence of different isolates of the pathogen has been confirmed by Reddy et al (1990).…”

Inheritance of resistance to the ‘Kanpur’ race of Phytophthora drechsleri in pigeonpea

“…In this case it is clear that individuals possessing the dominant allele Pdr were susceptible and the individuals possessing the recessive gene in the homozygous condition (pdr pdr) were resistant. In contrast to these findings Sharma et al (1982) reported that a single dominant gene was responsible for the inheritance of resistance to race P2. A resistant reaction was shown by all individuals in the F 1 , F 2 , BC 1 and BC 2 generations of the crosses between resistant parents because of the presence of only recessive genes imparting resistance in the resistant parents.…”

“…The susceptible reaction of individuals in the F 1 generation of the crosses between resistant and susceptible parents (Table 1) indicated that the susceptible reaction is dominant over the resistant reaction to the race KPR, while Sharma et al (1982) reported that the resistant reaction was dominant over the susceptible reaction to the race P2. This contradiction may be resulted from the matching or overcoming of all the genes for resistance in the individuals of F 1 generation with those of genes for virulence in the KPR race in the present investigation, while the genes for virulence present in the P2 race could not match or overcome all the genes responsible for resistance in the individuals of the F 1 generation in the investigation of Sharma et al (1982). From these results it could be concluded that the level of virulence in different races may be different, which also depends upon the resistant genes present in the resistant donors.…”

“…P4, P3, BHU, KPR, P2, HIS, IARI and P2BF of P. drechsleri on the basis of variable reactions of 13 pigeonpea genotypes in pot culture at different locations, which confirmed the variability in races of P. drechsleri. As information on the inheritance of resistance is reported only for the P2 race (Sharma et al 1982), the present investigation was undertaken to clarify the inheritance of resistance to the KPR race of P. drechsleri in the resistant donors of pigeonpea.…”