Application of photochemical parameters and several indices based on phenotypical traits to assess intraspecific variation of oat (Avena sativa L.) tolerance to drought

Izabela Marcińska,Marzena Popielarska-Konieczna,Stanisław Grzesiak,Ilona Czyczyło-Mysza,Edyta Skrzypek,Maciej T. Grzesiak,Marzena Warchoł

doi:10.1007/s11738-017-2453-2

Abstract

Functionality of the photosynthetic system under water stress is of major importance in drought tolerance. Oat (Avena sativa L.) doubled haploid (DH) lines obtained by pollination of F1 oat crosses with maize were used to assess the differences in plant genotypic response to soil drought. The investigations were based on the measurements of gas exchange and chlorophyll a fluorescence kinetics. Drought was applied to 17-day-old seedlings by withholding water for 14 days and subsequent plant recovery. Non-stressed optimally watered plants served as controls. Yield components were determined when plants reached full maturity. It was shown differences among the oat lines with respect to drought stress susceptibility (SI) and stress tolerance index mean productivity and drought susceptibility index. Sensitivity to drought of individual DH lines was significantly different, as demonstrated by the correlation between drought susceptibility index and yield components, such as dry weight (GW) or grain number (GN) of the harvested plants. GW and GN were lower in drought-sensitive genotypes exposed to drought stress compared to those resistant to drought. The principal component analysis allow to separate three groups of lines differing in their sensitivity to drought stress and indicated that tolerance to drought in oat has a common genetic background.

Highlights

The common oat (Avena sativa L.) is an important cereal cultivated worldwide, which occupies the eighth place in the world cereal production
Correlation coefficients indicated that drought sensitivity index (DSI), SI and MP provided the most suitable criteria for the selection of high yielding genotypes under water stress conditions
It was possible to distinguish three groups of doubled haploid (DH) lines (I, II and III) with a low, moderate and strong sensitivity to drought. By comparing it with yield components, we found that the lines from group I produced the highest grain yield, group II produced lower grain yields under both conditions, and group III had the lowest values of yield components

Summary

Introduction

The common oat (Avena sativa L.) is an important cereal cultivated worldwide, which occupies the eighth place in the world cereal production. Oat grain is an important source of feed, pharmaceutical and cosmetic products, Page 2 of 13. Understanding the responses of plants to drought is of great importance and constitutes a fundamental prerequisite in the development of stress tolerance in crops (Zhao et al 2008). Drought resistance is defined as the capacity of plants in withstanding the periods of dryness and is related to phenotypic, morphological and physiological factors (Zhang et al 2011; Yan et al 2012). For qualitative and quantitative evaluation, it is necessary to estimate the influence of drought during the all growing period and assess both the immediate and indirect physiological and morphological reactions of plants. The plant responses help manage the unfavorable stress conditions, either by increasing resistance to damage or sustaining metabolic functions under limited water conditions (tolerance mechanisms)

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