Analysis of radiographic images and germination of Campomanesia pubescens (Mart. ex DC.) O.Berg (Myrtaceae Juss.) seeds under drying.

E V E J Amaral,J Zuchi,J M G Neves,J A Oliveira,J F Sales

doi:10.1590/1519-6984.219950

Abstract

The objective of this study was to evaluate the internal morphology of seeds of Campomanesia pubescens (Mart. ex DC.) O. Berg with varying water content through X-ray image analysis, and correlate the images with the germination of these seeds. Fruits were collected in Jataí, Goiás, Brazil, and taken to the Seed Laboratory of the Federal Institute Goiano, Rio Verde Campus, where they were processed and the seeds were extracted. To establish the predetermined water content (43%, 37%, 34%, 31%, and 28% wet basis), seeds with an initial water content of 43% were kept in an oven with forced air circulation at a temperature of 40 °C until they reached the predetermined water content levels. Next, the seeds were placed in acrylic holders with double-sided tape and transported to the Federal University of Lavras (UFLA), where they were exposed to different intensities of radiation. The X-ray test was conducted with 200 seeds per treatment, and images of the internal structures of the seeds were evaluated. The seeds were returned to the Seed Laboratory of the Federal Institute Goiano, Rio Verde Campus, where the germination test was initiated. The experimental design was completely randomized, in a factorial design (5 × 4), in which there were five water content levels and four seed classes, with four replications. The X-ray test was efficient in the identification of filled, malformed, damaged and empty seeds, which germination rate above 50% in the filled seeds. This visualization of the internal morphology of the seed can be useful to select seeds of better quality, improving the percentage of germination of C. pubescens seeds.

Highlights

The Myrtaceae family consists of 23 genera and 1,029 species, of these, 790 are endemic to Brazil
The fruits of C. pubescens were collected from approximately 50 plants in early November 2014 from a farm located in the county of Jataí, Goiás, Brazil (18°12’10”S and 51°44’51”W) and taken to the Seed Laboratory of the Federal Institute Goiano, Rio Verde Campus, where they were processed and the seeds were extracted
The analysis of the X-ray images allowed the internal morphology of C. pubescens seeds to be observed and the identification of the following seed classes: filled seeds (A) with their embryonic cavities fully filled, and with their embryos and cotyledons well formed; malformed seeds (B) with their embryonic cavities not fully filled, and with their embryos and/or cotyledons malformed; damaged seeds (C) with some mechanical damage to their structure; and empty seeds (D), with their embryonic cavity empty (Figure 1)

Summary

Introduction

The Myrtaceae family consists of 23 genera and 1,029 species, of these, 790 are endemic to Brazil. The genus Campomanesia stands out with 39 species distributed in almost every national territory, of which 29 are endemic (Sobral et al, 2015). It is endemic to Brazil, and is found throughout the Midwestern state and in some northern, northeastern, southeastern, and southern states (Sobral et al, 2015). Has great potential for cultivation in new areas, since they are not very demanding on soil besides they present special flavors, with great concentration of sugars, proteins, vitamins, minerals and fibers (Martins et al, 2015), have medicinal characteristics (Dousseau et al, 2011). Besides it presents fruits with potential to revegetate areas contaminated with oily residues and their fruits are very appreciated by the fauna (Gogosz et al, 2010)

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