Using Morphological and Physiological Traits to Evaluate Drought Tolerance of Pear Populations ( Pyrus spp.)

Abstract

The use of drought-tolerant rootstocks is one of the available solutions for the cultivation of pear in semi-arid areas. In order to achieve drought-tolerant rootstocks, seeds of Pyrus syriaca, and Pyrus salicifolia species as well as Pyrus communis cv. Spadona, Khoj no. 1 and Khoj no. 2 were cultivated in the field conditions. This research was carried out as a factorial experiment with two factors of pear species (in five levels) and water stress (in two levels of control and drought stress) based on a randomized complete block design. In drought treatment, the irrigation time was considered based on 80% of allowed water depletion. In control blocks, normal irrigation was performed. The experiment began in July and continued to late September. In stress conditions, P. communis cv. Spadona and Khoj no. 1 had the highest seedling height and stem diameter and P. salicifolia and P. communis cv. Khoj no. 2 had the lowest of the rate of these traits. The lowest increase in electrolyte leakage (EL) and the highest proline content were in P. communis cv. Khoj no. 2 and P. salicifolia and the highest EL and the lowest proline were observed in P. communis cv. Spadonain under drought stress conditions. The most and the least relative water content (RWC) were belonged to P. communis cv. Khoj no. 2 and Spadona, respectively, in stress conditions. According to the studied traits, P. salicifolia and P. communis cv. Khoj no. 2 populations were more tolerant to drought stress.

Drought Effects on Morpho-Physiological and Biochemical Traits in Persian Oak and Black Poplar Seedlings

“…Foliar chlorophyll content is tightly correlated with leaf photosynthetic capacity [59]. Drought-driven reductions in leaf chlorophyll and carotenoid content commonly result from chloroplast damage by reactive oxygen species (ROS) and unaltered pigment levels during drought stress thus indicate superior ROS scavenging by antioxidants conferring enhanced drought tolerance [60]. In our experiment, both species showed similar pigment contents and drought-related decreases, apart from the maintenance of carotenoid levels under moderate SWD in Persian oak.…”

Orchard Management and Incorporation of Biochemical and Molecular Strategies for Improving Drought Tolerance in Fruit Tree Crops

“…It is essential to find strategies to improve the resistance and tolerance of fruit species to drought by identifying their physiological, biochemical, and molecular parameters. Using drought-resistant species as rootstocks is one of the most optimal solutions to plant production in arid regions [ 11 ]. The tree canopy, for instance, plays an important role in tree adaptation to drought conditions, so dwarf cultivars with dense canopies are more resistant to water stress than broad-canopied cultivars [ 12 ].…”

Photosynthetic Variability of Oblačinska Sour Cherry Ecotypes under Drought

“…Understanding the impact of drought on the association of leaf water with photosynthetic parameters is important for understanding the physiological mechanisms of drought tolerance and identifying tolerant genotypes of a species [6]. A widely used indicator of water status in plants under drought is leaf-relative water content (RWC) [7,8]. Water relations between soil and leaves correlate through the soil water content and RWC [9], suggesting drought conditions when they are reduced compared to optimal conditions.…”

“…Further, fruits of Oblačinska sour cherry ecotypes in different ecological conditions reveal significant changes in their nutritional values [28,29], indicating that adverse ecological conditions, such as temperature or rainfall, could differentially affect metabolic processes in Oblačinska sour cherry ecotypes. Given the ubiquity of climate change, understanding the morpho-anatomical and physiological changes in tolerance to drought stress can be used to select available genotypes or as a breeding tool for the creation of new genotypes which will be tolerant to drought [7,8,30,31].…”