Local Adaptation? — Physiological and Biochemical Responses of four Hazelnut Populations to Drought and Possible Impacts on Tree Nurseries

Abstract

Outplanting performance of trees and shrubs cultivated in tree nurseries is assumed to be better if propagation material is sourced from the designated areas of future growth. However, this requires a local nursery to produce that cultivar, which might reduce the availability of that species. In this study we evaluated drought reactions of 2.5-year-old hazelnut (Corylus avellana L.) from four population origins. After container cultivation, plants were subjected to drought by irrigating 25% (fast stress) or 50% (slow stress) of the lost water. Control plants were well irrigated. Depending on stress development and hence stress duration, different physiological (stomatal conductance, predawn water potential, relative water content) and biochemical (glucose, fructose, sucrose, starch, proline) responses to drought were found. Independent of stress development, only few differences among populations were found. These differences were mostly not related to precipitation in their area of origin, suggesting no local adaptation within the ecological range investigated.

Drought stress reactions of different populations of Quercus robur L. and Tilia cordata Mill.1

“…Physiological drought stress reactions did not indicate local adaptations for Quercus robur populations, even though they differ in precipitation conditions at the site of origin. Similar results are reported by Wanjiku and Bohne (2016) for hazelnut populations. Concerning the influence of drought on growth, this contrasts results of Arend et al (2011) who found provenance-specific responses for Quercus robur.…”

Biological Flora of Britain and Ireland:Corylus avellana

“…Transpiration experiments by Fordham et al (2001) found that, when rooted cuttings are removed from the humid environment required to achieve high rooting success, the cause of severe water deficit is unregulated opening of leaf stomata. Wanjiku and Bohne (2016b) reported an absence of local adaptation of the drought reaction, finding insignificant differences in the stomatal conductance, predawn water potential, and relative water content between regions. In studies on water percolation, Ayyanath et al (2021) concluded that snow helps regulate the root zone temperature, and that in C. avellana the presence of snow cover results in an increased probability of female flowers from dormant buds, leading to an improved percentage and prolonged receptivity of female flowers.…”