Role of Abscisic Acid in Drought-Induced Freezing Tolerance, Cold Acclimation, and Accumulation of LT178 and RAB18 Proteins in Arabidopsis thaliana

Abstract

To study the role of abscisic acid (ABA) in development of freezing tolerance of Arabidopsis fhaliana, we exposed wild-type plants, the ABA-insensitive mutant abil, and the ABA-deficient mutant aba-1 to low temperature (LT), exogenous ABA, and drought. Exposure of A. fhaliana to drought stress resulted in a similar increase in freezing tolerance as achieved by ABA treatment or the initial stages of acclimation, suggesting overlapping responses to these environmental cues. ABA appears to be involved in both LT-and drought-induced freezing tolerance, since both ABA mutants were impaired in their responses to these stimuli. To correlate enhanced freezing tolerance with the presence of stressspecific proteins, we characterized the accumulation of RABl8 and LU78 in two ecotypes, Landsberg erecta and Coimbra, and in the ABA mutants during stress response. 11-and drought-induced accumulation of RABl8 coincided with the increase in freezing tolerante and was blocked in the cold-acclimation-deficient ABA mutants. In contrast, LT178 accumulated in all genotypes in response to LT and drought and was always present when the plants were freezing tolerant. This suggests that development of freezing tolerante in A. fhaliana requires ABA-controlled processes in addition to ABA-independent factors.

Relationship between water use efficiency (WUE) and production of different wheat genotypes at soil water deficit

“…Unlocking the physiological and molecular basis for the plasticity of plant defending metabolism not only provides access to a largely untapped resource of genes and selection markers for breeding enhanced stress tolerance in crops but also ensures improved food security and agricultural sustainable development worldwide [5,8,10,19,32,44,48,52,62].…”

“…Just 1 year ago, European Commission, who once kept conservative to biotechnological breeding, constructed a big project: Plants for the Future: a European vision for Plant Biotechnology towards 2025, in which much is involved in resistance drought [14]. Many advances in relation to this hot topic, including molecular mechanism of anti-drought and corresponding molecular breeding have taken place [28,33,34,39,44,47,50,53,[55][56]63,[72][73][74][75]78]. Although the obtained transgenic crops (mainly, wheat) by different types of gene technology all exhibit drought resistance to some extent, they have many shortfalls related to agronomical performance and/or development [47,49,53,62,66,68,74].…”

Changes of some anti-oxidative physiological indices under soil water deficits among 10 wheat (Triticum aestivum L.) genotypes at tillering stage

“…Drought is a worldwide problem, constraining global crop production seriously [1,2,5,7,[19][20][21]37,45,46,59] and recent global climate change has made this situation more serious [15,30,32,35,38,64]. Drought is a complex physical-chemical process, in which many biological macromolecules and small molecules are involved, such as nucleic acids (DNA, RNA, microRNA), proteins, carbohydrates, lipids, hormones, ions, free radicals, mineral elements [3,8,12,13,18,20,22,26,31,43,49,50,55,65].…”

“…Drought is a complex physical-chemical process, in which many biological macromolecules and small molecules are involved, such as nucleic acids (DNA, RNA, microRNA), proteins, carbohydrates, lipids, hormones, ions, free radicals, mineral elements [3,8,12,13,18,20,22,26,31,43,49,50,55,65]. In addition, drought is also related to salt stress, cold stress, high temperature stress, acid stress, alkaline stress, pathological reactions, senescence, growth, development, cell cycle, UV-B damage, wounding, embryogenesis, flowering, signal transduction and so on [16,17,[26][27][28]36,37,[44][45][46][47][52][53][54]62]. Therefore, drought is connected with almost all aspects of biology.…”

“…Just 2 years ago, European Commission, who once kept conservative to biotechnological breeding, constructed a big project: Plants for the Future in which much is involved in resistance drought [5]. Many advances in relation to this hot topic, including molecular mechanism of antidrought and corresponding molecular breeding have taken place [4,10,16,17,21,[23][24][25]30,31,35,37,39,42,48,[55][56][57][58][59]. Although the obtained transgenic crops (mainly, wheat) by different types of gene technology all exhibit resistance drought to some extent, they have many shortfalls related to agronomical performance and/or development [1,16,17,21,24,30,39,49,56].…”