Pollen grain germination and fruit set in 'Brazilian seedless' sugar apple (Annona squamosa L.)

Abstract

Abstract

Stenospermy and seed development in the “Brazilian seedless” variety of sugar apple (Annona squamosa)

“…STENOSPERMY AND STERILE SEEDS IN A. squamosa Annona squamosa also indicated that this trait is recessive in nature (S. Nietsche et al, unpublished data). Furthermore, the dependence on pollination (Mendes et al 2012), the production of fruits of normal shape and size, the peculiar structure of the ovule, the occurrence of fertilization and embryo degeneration in the 'Brazilian Seedless' mutant are all similar to descriptions of the stenospermic 'Thai seedless' access (Lora et al 2011). The majority of gynoecium characteristics observed in the present study are typical of Annonaceae (Svoma 1998b, Judd et al 1999) and were observed in the normal reference variety.…”

“…Hormonal control of pericarp formation generally involves stimulation by auxin provided by developing seeds (Taiz and Zeiger 2010). It is possible that this also occurs in aspermic A. squamosa fruits, which could explain the dependence of fruit development on pollination (Mendes et al 2012).…”

“…Floral buds in pre-anthesis were collected, and the material was fixed in Karnovsky solution (Karnovsky 1965) for 48 hours and preserved in 70% alcohol (Jensen 1962). The flowers were artificially pollinated using pollen from wild-type plants with normal fruit, according to the methodology described by Mendes et al (2012). Flowers were collected 24 hours after pollination, and developing fruit were collected at 48, 72 and 96 hours, and seven, ten, 15 and 90 (mature fruit) days after pollination.…”

“…The aim of the present study was to describe the gynoecium and developing fruit in a Brazilian mutant of A. squamosa that produces aspermic fruits following pollination (Mendes et al 2012) (Figure 1). In particular, we sought to answer the following questions: i) what type of aspermia is occurring and how similar is it to that observed in 'Thai seedless' mutant?…”

Doses de ácido giberélico na frutificação efetiva e qualidade de frutos de atemoieira 'Gefner'

“…Estudos conduzidos com este híbrido entre pinha (Annona squamosa L.) e cherimólia (Annona cherimola Mill.) apontam a baixa viabilidade polínica e níveis reduzidos de pegamento dos frutos (JALIKOP; KUMAR, 2007;MENDES et al, 2012). Entretanto, os frutos de atemoieira precisam ser polinizados artificialmente, utilizando-se mais recentemente do pólen da pinha que, apesar de se desenvolverem normalmente, têm a desvantagem de apresentar um grande número de sementes, além do alto custo associado à mão de obra da polinização artificial (PEREIRA et al, 2011).…”