Development of the ovular structures in peach [Prunus persica (L.) Batsch]

Abstract

SUMMARYChanges in the ovular tissues of peach (Prunus persica (L.) Batsch) were studied from anthesis to fertilization or degeneration in pollinated and unpolHnated flowers. During this time the ovule undergoes a continuous developmental process. At anthesis the megagametophyte is immature and is not fully developed until 12 days later. Durmg the first three weeks following anthesis the ovule increases in length from 400 to 1200/fm, and the nucellus and integuments undergo various changes particularly in the distribution of starch and cutin. These appear to be connected with early embryo sac nutrition and protection. As the ovule matures, starch accumulates mainly in the embryo sac, integuments and at the nucellar tip. This starch disappears during early embryo sac elongation. Concomitant with starch depletion, the cutin that separated the integuments from the nucellus vanishes. Other cutin accumulates between cells in the nucellar tip, thus protecting and isolating the embryo sac. Most of these changes appear to be a fixed feature of ovule development since they were also observed in a few long lived ovules in unpollinated flowers. However, in unpolHnated fiowers development of most of the ovules is soon interrupted: callose accumulates at the chaiaza, starch disappears and the ovules degenerate.

The Reproductive Biology of Selected Taxa of the Genus Cerasus Duham

“…In line with observations of Cerović andMićić (1999) in C. avium andArbeloa andHerrero (1991) in P. persica, we found antipode degeneration before fertilization. These authors observed antipode degeneration 3 days after they developed.…”

Male and female synchrony and the regulation of mating in flowering plants

“…B (2003) clear. Indeed, in some species such as in the peach (Arbeloa & Herrero 1991), the female gametophyte does not even exist at the time when the sporophytic machinery necessary for fertilization is established. There is little information on the lifespan of the megagametophyte, but observations on Prunus species (M. Herrero, unpublished results) show that it is surprisingly short.…”

Desenvolvimento floral e produção de pessegueiros 'granada' sob distintas condições climáticas

“…As reservas de amido desempenham um importante papel no processo reprodutivo (HERRERO; HORMANZA, 1996), pois influenciam no desenvolvimento das estruturas ovulares e no desenvolvimento do embrião (ARBELOA; HERRERO, 1991).…”