|dc.description.abstract||Pigeon pea (Cajanus cajan (L.) Millsp.) is a drought tolerant pulse legume, mainly grown for grain in the semiarid
tropics, particularly in Africa. Pigeon pea production in countries like Kenya is faced with a number of
challenges, particularly lack of high quality seeds. The objective of this study was to develop an in vitro
regeneration system for pigeon pea varieties grown in Kenya, that is amenable to genetic transformation. In vitro
regeneration of pigeon pea varieties, KAT 60/8 and ICEAP 00557, commonly grown in Kenya was achieved
using leaf explants from in vitro grown seedlings, through callus initiation, followed by shoot and root induction.
For callus initiation, MS media supplemented with 0.5-4 mg l-1 2, 4-D and TDZ separately were tested, and IBA
at 0.1, 0.5 and 1 mg l-1 was tested for rooting of shoots. Embryogenic calli was obtained on MS containing 2, 4-
D; whereas TDZ induced non-embryogenic callus alone or with shoots directly on explants. Indirect shoot
regeneration frequency of 6.7 % was achieved using 1 mg l-1 2, 4-D-induced embryogenic callus obtained using
KAT 60/8 explants. Whereas direct shoot regeneration frequencies of 20 and 16.7% were achieved using ICEAP
00557 and KAT 60/8 explants, using 0.5 mg l-1 and 2 mg l-1 TDZ, respectively. Optimum rooting was achieved
using 0.5 mg l-1 IBA; and up to 92% rooted shoots were successfully established in soil after acclimatisation.
Genotype and hormone concentrations had a significant (P<0.05) influence on callus, shoot and root induction.
The protocol developed can be optimised for mass production and genetic transformation of KAT 60/8 variety.||en_US