Induction of fruit set and development in pea ovary explants by gibberellic acid

Abstract

The response of unpollinated ovary explants of Pisum sativum L. cv. Alaska No. 7 to several plant growth regulators and nutrients has been studied. Explants consisted of a segment of stem and an emasculated flower with or without the adjacent leaf. They were made on the day equivalent to anthesis and were cultured in a liquid medium. Growth regulators were applied either in the solution or directly to the ovaries. Gibberellic acid (GA 3) in the presence of sucrose, but not indole-3-acetic acid or N6-(A2-isopentenyl)-adenine (2iP), induced fruit set and development of parthenocarpic fruits, the final length of these being a function of the intensity of the GA 3 treatment. The capacity of ovaries to respond fully to GA 3 was not lost after incubation of explants in water or 50 mM sucrose for 1 day and was similar in explants made between the day of anthesis and 3 days later. Limited growth was obtained with 100 mM sucrose alone but this effect was counteracted by 2'-isopropyl-4'-(trimethyl ammonium chloride)-5'-methylphenyl piperidine-l-carboxylate (AMO-1618). This inhibitor was ineffective when GA 3 was applied to the ovary. The development of the fruit was proportional to the length of the segment of stem up to 5 cm. The presence of the leaf in the explant enhanced the development of the fruit. These results indicate that a gibberellin is necessary for setting and development of fruits from cultured ovaries and that this effect depends on an appropriate source of nutrients. The course of development of parthenocarpic fruits on explants was similar to that of seeded fruits on the intact plant. The cultured pea ovary system offers convenient means to investigate the role of gibberellins and nutrients in fruit set and development. Nitsch (1951) described techniques of fruit culture in vitro using explants retaining a small portion of pedicel. Ovaries from pollinated flowers of different

Hormonal regulation of flowering and fruit development: Effect of gibberellic acid and ethrel on fruit setting and development ofMomordica charantia L.

“…The percentage of fruit production was increased in all treated plants over control. This finding is in agreement with reports On GA3-induced fruit set in plants other than cucurbits (Agusti et al 1982, Holloway-Patrica et al 1982, Garcia-Martinez and Carbonell 1985 and on the effect of ethrel on growth, flowering and fruit formation of three cucurbits (Sadhu and Das 1978).…”

‘Pod shatter’ in Arabidopsis thalianaBrassica napus and B. juncea

“…Pea (Pisum sativum) has been used to study the effects of gibberellic acid on fruit set and development. Garcia-Martinez & Carbonell (1980, 1985 found that unpollinated pea ovaries treated with gibberellic acid/(GA3) developed into mature fruits, while unpollinated untreated ovaries senesced. The cells of the pea carpel walls enlarge and differentiate as the fruit matures following pollination.…”