Overexpression of StDREB2 Transcription Factor Enhances Drought Stress Tolerance in Cotton (Gossypium barbadense L.)

Abstract

Drought stress significantly restricts plant growth and crop productivity. Cotton is the most important textile fiber and oilseed crop worldwide, and its cultivation is affected by drought stress, particularly in dry regions. Improving cotton tolerance to drought stress using the advanced genetic engineering technologies is a promising strategy to maintain crop production and fiber quality and meet the increasing worldwide fiber and oil demand. Dehydration-responsive element binding (DREB) transcription factors play a main role in regulating stresses-tolerance pathways in plant. This study investigated whether potato DREB2 (StDREB2) overexpression can improve drought tolerance in cotton. StDREB2 transcription factor was isolated and overexpressed in cotton. Plant biomass, boll number, relative water content, soluble sugars content, soluble protein content, chlorophyll content, proline content, gas-exchange parameters, and antioxidants enzymes (POD, CAT, SOD, GST) activity of the StDREB2-overexpressing cotton plants were higher than those of wild type plants. By contrast, the contents of malondialdehyde, hydrogen peroxide and superoxide anion of StDREB2-overexpressing transgenic plants were significantly lower than that of the wild type plants. Moreover, the transgenic cotton lines revealed higher expression levels of antioxidant genes (SOD, CAT, POD, GST) and stress-tolerant genes (GhERF2, GhNAC3, GhRD22, GhDREB1A, GhDREB1B, GhDREB1C) compared to wild-type plants. Taken together, these findings showed that StDREB2 overexpression augments drought stress tolerance in cotton by inducing plant biomass, gas-exchange characteristics, reactive oxygen species (ROS) scavenging, antioxidant enzymes activities, osmolytes accumulation, and expression of stress-related genes. As a result, StDREB2 could be an important candidate gene for drought-tolerant cotton breeding.

Transcriptome Analysis Reveals Potential Roles of Abscisic Acid and Polyphenols in Adaptation of Onobrychis viciifolia to Extreme Environmental Conditions in the Qinghai-Tibetan Plateau

“…Ectopic expression of StDREB2 of Solanum tuberosum in cotton ( Gossypium barbadense ) enhanced the drought resistance, while ectopic expression of ScDREB10 of Syntrichia caninervis in Arabidopsis increased osmotic and salt tolerance of transgenic plants. Furthermore, overexpression of TaDREB3 improved frost resistance of transgenic wheat seedlings [ 59 , 60 , 61 ]. In addition, DEAR4 which is a member of the DREB subfamily was reported to positively regulate the cell death and leaf senescence, and to be responsive to multiple stressors in A. thaliana [ 62 , 63 ].…”

Serratia marcescens BM1 Enhances Cadmium Stress Tolerance and Phytoremediation Potential of Soybean Through Modulation of Osmolytes, Leaf Gas Exchange, Antioxidant Machinery, and Stress-Responsive Genes Expression

“…Net photosynthesis rate (P n ), transpiration rate (E), and stomatal conductance (g s ) were measured on expanded leaves of similar developmental stages with a portable gas-exchange system (LI-6400, LI-COR Inc., Lincoln, NE, USA) between 9:30 and 10:30 am, according to the methodology of Holá et al [50]. Leaf relative water content (RWC) was determined as previously explained by El-Esawi and Alayafi [12].…”

“…Cadmium retards vital physio-biochemical activities in plants, which include photosynthesis, biosynthesis of chlorophyll and accessory pigments, and the uptake and assimilation of essential mineral nutrients by triggering the overproduction of reactive oxygen species (ROS), including singlet oxygen ( 1 O 2 ), hydrogen peroxide (H 2 O 2 ), superoxide radical (O 2 • − ), and the hydroxyl radical (OH•) [5,6]. ROS accumulation causes high toxicity in plant cells [7][8][9][10][11][12][13][14][15][16]. Cadmium evokes peroxidation of membrane lipids and modulates the expression of genes of antioxidant defense systems in plants [17].…”

Sodium Azide Priming Enhances Waterlogging Stress Tolerance in Okra (Abelmoschus esculentus L.)

“…Okra originated in Ethiopia and was then reproduced in the Mediterranean area, North Africa, and India [1]. Environmental stresses negatively affect the growth, yield, and biological activities of plants worldwide [2][3][4][5][6]. In particular, waterlogging the seeds were removed and washed 5 times with deionized water to remove all traces of NaN 3 .…”