Genetic control of a branching peduncle mutant of cow pea, Vigna unguiculata (L.) Walp.

Abstract

SUMMARYA branching peduncle individual was observed in a population of cow pea Vigna unguiculata (L.) Walp. cv. Ife Brown. Normal plants have unbranched peduncles with flowers arranged in alternate pairs at distal ends of the peduncles. However, the mutant plant has branched peduncles with flowers arranged in pairs alternately along the branches as well as at the ends of the branches. The branches arise in the axils of stipulate trifoliate leaves which develop on the peduncles. The normal plant has between one and four pods per peduncle, whereas the mutant is capable of carrying between two and ten pods per peduncle. The branching trait is under genetic control, involving a single gene with the normal peduncle completely dominant over the mutant. Evidence for the genetic control and its possible usage is discussed. Data on some agronomic properties of the mutant are also presented.

Potencial genético de progênies de feijão-caupi segregantes quanto ao tipo da inflorescência

“…Em estudos de controle genético da inflorescência em feijão-caupi, foram identificados dois genes recessivos responsáveis pela expressão da inflorescência composta, o gene ci (Sen & Bhowal, 1961) e o gene bp (Fawole & Afolabi, 1983). Machado et al (2007), ao estudar o controle genético para a inflorescência composta na cultivar Cacheado, concluíram que a herança é monogênica recessiva.…”

Incorporation of compound inflorescences and selection of high-yielding progenies in cowpea

“…All annual legumes with high-yielding potential have compound inflorescences arranged in racemes, such as soybean (Hartung et al, 1981), common bean (Teixeira et al, 1999;Kelly, 2001), and chickpea (Cicer arietinum L.) (Gaur & Gour, 2002). However, cowpea cultivars released in the Brazilian market have simple inflorescences, with no exception, although there are records of this species having compound inflorescences worldwide (Araújo et al, 1981;Fawole & Afolabe, 1983;Sen & Bowal, 1961) -a cultivar with this trait, for example, was released in Nigeria (Fawole et al, 1985).…”

“…Compound inflorescences in cowpea is a trait of easy fixation, since its presence is conditioned by recessive monogenic inheritance (Fawole & Afolabe, 1983;Machado et al, 2007). Moreover, it is a trait of easy identification, which facilitates selection at an early generation (Fehr, 1987).…”