Physiology and quality of Eugenia dysenterica DC seedlings grown in vermiculite and rice husk-based substrates

Abstract

Eugenia dysenterica DC is a fruiting species endemic to the Brazilian Cerrado, belonging to the Myrtaceae family and popularly known as Cagaiteira. It has medicinal and antifungal properties, and has an important function in the ecosystem. Nevertheless, there are few studies about the maintenance of this species. The aim of this study was to evaluate the growth, nutrition, quality and physiology of E. dysenterica seedlings grown in fine vermiculite and rice husk-based substrates in the following combinations: 1:0, 3:1, 1:1, and 1:3, in addition to Trimix® commercial substrate and vermiculite only. The physical attributes of substrates (dry and moist densities, available water, remaining water, aeration space and total porosity), seedling emergence percentage, emergence speed index, gas exchange, chlorophyll a fluorescence, relative seedling water content, relative substrate moisture content, plant biometric growth characteristics, accumulated dry weight and nutritional status were evaluated through leaf macronutrient content 128 days after emergence. The increase in the proportion of rice husk mixed with vermiculite resulted in reduction of the dry and moist densities of substrates, available water, remaining water, total porosity and moisture content, and increased the aeration space in substrates. The fine vermiculite substrate promoted the highest Dickson’s quality index and the greatest stem diameter of plants. Seedlings grown on vermiculite substrate presented higher N and K content in leaves, and those grown in Trimix® substrate showed higher leaf Mg content. Substrates did not alter the physiological attributes of seedlings.

Biometric and morphological adjustments of Eugenia. dysenterica DC. seedlings in response to increased soil water deficit

“…The mother plants from seeds of different sizes present a better initial growth when the seeds have the greatest volume (Nietsche et al, 2004). The maximum SD value found for both plants at 120 DAD was 1.66 mm (Table 4), as expected for this species at this age (270 DAE), similarly to the values obtained by Mota et al (2018).…”

“…The tree species under growth tend to increase vertically and stabilize radially; thus, a temporal increase in the SH/SD ratio is expected when there is better nutritional status in the plant (Trouet et al, 2012;Marcati et al, 2016;Mota et al, 2018). According to Fonseca, Valéri, Miglioranza, Fonseca, and Couto (2002), in a study on shading with Trema micrantha L. seedlings, a pioneer species that have fast growth and is unsuitable to humid environments, showed a significant linear increase in the ratio, explained by the increase in shoot height and reduction in lap diameter (Marcati et al, 2016).…”

Genetic variability of the initial growth of Eugenia dysenterica DC.: implications for conservation and breeding1

“…provenance and progeny testing.Genetic variability of the initial growth of Eugenia dysenterica DC. : implications for conservation and breeding 80.6(Souza et al 2001) to 99 %(Mota et al 2018).…”