Acorn size influence on the quality of pedunculate oak (Quercus robur L.) one-year old seedlings

Jovana R Devetaković,Vladan Popović,Mirjana Šijačić-Nikolić,Marina Nonić,Bojan Prokić

doi:10.21750/refor.8.02.72

Abstract

Pedunculate oak (Quercus robur L.) is one of the most important deciduous tree species in the Serbian and European forests. Different negative factors limit natural regeneration of pedunculate oak forests, so producing of high quality seedlings becomes imperative to ensure successful forest restoration. This research was conducted with to aim to determine whether acorn size is related to seedlings quality. Acorns were collected from the natural pedunculate oak forest and divided into two groups by their size. Acorns were sown in the spring into plastic containers after five months cold storage. Size of acorns was in the standard species range, though germination was low (< 20 %). Germination was more then double in group of large acorns in comparison to group of smaller acorns (19.2 %, respectively 8.6 %). Height and root collar diameter of produced seedlings were lower than seedlings produced in seedbeds in commercial nurseries in Serbia, but it was in range of container produced seedlings in some similar researches. Height to root collar diameter ratio and shoot to root ratio were considered as satisfactory for containerized seedlings. There was not strong correlation between acorn size and seedlings quality attributes.

Highlights

Acorn size; Pedunculate oak; Seedlings quality required because of the high value of pedunculate oak wood has caused harvesting pressure on this forest and adverse site conditions have limited natural regeneration (Dubravac and Dekanić 2009; Medarević et al 2009; Tikvić et al 2011; Bauer et al 2013)
From the genetic aspect an advantage is given to natural regeneration of oak forests (Ducousso and Bordacs 2004), but the regular yield of quality seeds is necessary to ensure natural regeneration
The thousand seed mass (TSM) was almost double for the large acorns compared to the small group of acorns

Summary

Introduction

Acorn size; Pedunculate oak; Seedlings quality required because of the high value of pedunculate oak wood has caused harvesting pressure on this forest and adverse site conditions have limited natural regeneration (Dubravac and Dekanić 2009; Medarević et al 2009; Tikvić et al 2011; Bauer et al 2013). Irregular yield and problematic natural regeneration of forests increases the need for growing and planting seedlings to ensure restoration success. Other studies looking a seed size to young seedling development have been conducted within the genus Quercus, with some studies confirming (Navarro et al 2006; Roth et al 2009; Tilki et al 2009; Roth et al 2011: Popović et al 2015), while other work not confirming (Ivanković et al 2011) this hypotesis

Objectives

Methods

Results

Conclusion