Description

Abstract: Embryo rescue techniques in Arachis are potentially important for recovering interspecific hybrids which have the propensity to abort. Pegs are commonly produced in interspecific crosses, but either they fail to reach the soil because growth is arrested, or pods are produced but embryo development is never re-initiated. Peg tips, with the ovule and embryo, of A. hypogaea L. cv. ‘NC 6’, were used to determine whether peg tips can be used as nurse tissue for in vitro culture of embryos. Tissues were collected 1, 2, 3 and 4 d after self-pollination, after which peg meristems were removed from half the pegs, and cultured on five media combinations. Continued reproductive development was observed for embryos cultured at all four collection days; however, the highest frequency of growth was observed in 1-d-old tissues. Evidence is presented that meristematic activity may restrict embryo growth in the 2- to 4-d-old embryos and, once the sequence of events is initiated to slow embryo growth, it is not easily reversed in vitro. Achievements of embryo growth to multicellular, globular stages (stages 1