The present study was conducted to evaluate three breeding methods i.e. Bulk Method, Single Seed Descent and Single Plant Progenies in F 4 generation of blackgram to identify the most appropriate one for particular hybrid or character at two locations. In addition, inheritance of qualitative traits and hybrid performance for four generations was also studied. Inheritance study comprised four plant traits (pubescence, pod colour, seed coat colour and presence of spots on seed coat) in three crosses. Breeding methods in eleven crosses were investigated for plant height, number of branches planrl, pods planrl, length pod-s, seed pod-s, 100 seed weight planrl, biological yield planrl, grain yield planrl and harvest index over four generation at National Agricultural Research Center, (research station) and Fateh Jang (farmer's field).
Eleven crosses were selected in F2 from a six parent diallel and seeds were divided into three groups to evaluate Bulk Method, Single Seed Descent and Single Plant Progeny method. Two crosses (Mash 1/9020 and 9020/9012) gave better response to Bulk Method at both the locations, while 9020/Mash 1 performed better for this method at NARC location only. All the crosses except 9025/Mash 1 and 9025/9026 showed their worth in single seed descent. In single plant progenies at FJ, all the crosses showed better performance except 9020/9012.
Plant height, pods planrl, pod length, seed pods-l, 100 seed weight, biological yield planrl and grain yield planrl showed better performance in single plant progenies at FJ while single seed descent showed its worth for number of branches, pods planrl, pod length, pod seed, biological yield planrl, grain yield planrl and harvest index at NARC location. Single plant progenies showed the best performance at FJ and it differed significantly for single seed descent at NARC. Bulk method revealed almost similar results at both the location with lowest index score.
Four parents (Mash 1, Mash 3, MM 33-40, and 45726) were used to study inheritance of four qualitative characters, i.e., pubescence, seed coat colour, presence of spots on the seed coat and pod colour. All the four qualitative traits revealed monogenic nature of inheritance segregating in Mendelian ratio (3: 1). The hairiness pattern was observed dominant over non-hairiness; brown seed coat colour dominant over green seed coat colour. Presence of spots on seed coat was dominant to absence of spots and black pod colour was dominant over brown pods in blackgram. Out of three hybrids, two (Mash IIMM33-40 and 45726IMM33-40) revealed linkage between pod colour vs presence of spots on seed coat and pod colour vs seed coat colour that is suggested to be used for preliminary mapping in blackgram.
The data were analyzed for hybrid vigour over the generations and it was observed that the source of variation attributed to hybrids as well as generations representing high proportions of the total sum of squares. A clear response for grouping of Fl and F2 was observed, whereas other two generations (F3 and F4) were intermixed, although a low level of separation was observed. On the basis of performance and hybrid vigour, three hybrids (Mash 3IMash 1, 9012/ 9025 and 9020IMash 1) exhibited better potential. The hybrids with high mean performance and hybrids vigour are expected to give better chance for selection to develop superior cultivars of blackgram.