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

Rayane C Dos Santos,Márcia R Costa,Maria Olívia Mercadante-Simões,Marlon C.T Pereira,Leonardo M Ribeiro,Silvia Nietsche

doi:10.1590/0001-3765201420140206

Rayane C Dos Santos, Márcia R Costa + Show 4 more

Open Access

https://doi.org/10.1590/0001-3765201420140206

Copy DOI

Abstract

Stenospermy was identified in naturally occurring sugar-apple (Annona squamosa) mutants with great potential for use in genetic improvement programs. However, to date, there have been no detailed studies of the development of aspermic fruit in this species. The aim of the present study was to characterize the anatomy of developing fruit in the 'Brazilian Seedless' mutant. Flower buds in pre-anthesis and developing fruits were subjected to common plant anatomy techniques. The abnormal ovules are unitegmic and orthotropic and have a long funiculus. There is evidence of fertilization, including the presence of embryos in early development and the proliferation of starch grains in the embryo sac. However, the embryos and embryo sac degenerate, although this does not affect pericarp development. Ovule abortion does not occur. The perisperm, which is formed from the peripheral layers of the nucellus, fills the cavity left by the embryo sac. The mature fruit contains numerous small sterile seeds with abundant perisperm and unlignified integument that is restricted to the micropylar region. The majority of perisperm cells are living and appear to be metabolically active in the periphery. Therefore, stenospermy leads to the formation of sterile seeds in A. squamosa, and the perisperm possibly play an important role in fruit development.

Highlights

Annona squamosa L. (Annonaceae), known as the sugar-apple, is a tropical species that produces fruits valued for their aroma and flavor (Pareek et al 2011), which are used to manufacture juices, ice creams and jellies (Figure 1) (Donadio 1997, Araújo and Alves 1999)
It is unknown if this pattern of stenospermy (Lora et al 2011) occurs more broadly in this species, and it may be responsible for other described cases of aspermia in the sugar apple (Araújo and Alves 1999, Manica 2003)
The plant material was collected from a natural mutant access of A. squamosa known as 'Brazilian seedless' from the Annonaceae orchard at STENOSPERMY AND STERILE SEEDS IN A. squamosa the experimental field of the State University of Montes Claros (Universidade Estadual de Montes Claros - Unimontes) in the municipality of Janaúba, Minas Gerais, Brazil

Summary

Introduction

Annona squamosa L. (Annonaceae), known as the sugar-apple, is a tropical species that produces fruits valued for their aroma and flavor (Pareek et al 2011), which are used to manufacture juices, ice creams and jellies (Figure 1) (Donadio 1997, Araújo and Alves 1999). (Annonaceae), known as the sugar-apple, is a tropical species that produces fruits valued for their aroma and flavor (Pareek et al 2011), which are used to manufacture juices, ice creams and jellies (Figure 1) (Donadio 1997, Araújo and Alves 1999) Adoption of this fruit tree in the market remains limited, its popularity could be expanded by developing varieties that are. As fruit development is commonly controlled by immature seeds (Taiz and Zeiger 2010), information on residual seminiferous structures could expand our knowledge concerning the formation of stenospermic fruit and aid in fruiting management It is unknown if this pattern of stenospermy (Lora et al 2011) occurs more broadly in this species, and it may be responsible for other described cases of aspermia in the sugar apple (Araújo and Alves 1999, Manica 2003)

Objectives

Methods

Results

Conclusion