Skip to main content
ARS Home » Plains Area » Lubbock, Texas » Cropping Systems Research Laboratory » Plant Stress and Germplasm Development Research » Research » Publications at this Location » Publication #327910
Title: Water-deficit inducible expression of a cytokinin biosynthetic gene IPT improves drought tolerance in cotton

Author
item KUPPU, SUNDARAM - Texas Tech University
item MISHRA, NEELAM - Texas Tech University
item HU, RONGBIN - Texas Tech University
item SUN, LI - Texas Tech University
item ZHU, XUNLU - Texas Tech University
item SHEN, GUOXIN - Zhejiang Academy Of Agricultural Sciences
item BLUMWALD, EDUARDO - University Of California
item Payton, Paxton
item ZHANG, HONG - Texas Tech University

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/13/2013
Publication Date: 5/10/2013
Citation: Kuppu, S., Mishra, N., Hu, R., Sun, L., Zhu, X., Shen, G., Blumwald, E., Payton, P.R., Zhang, H. 2013. Water-deficit inducible expression of a cytokinin biosynthetic gene IPT improves drought tolerance in cotton. PLoS One. 8(5):e64190.

Interpretive Summary: Water deficit stress is one of the most important factors that affect plant growth and development. Worldwide, crop losses worldwide due to abiotic stresses like drought and heat are result in mult-billion dollar impacts to economiesannually. Crop plants grown under rain-fed conditions are the most affected by seasonal variation in rain. Yield integrates many physiological processes that drive plant growth and development and most of these factors are affected by water-deficit stress. Plants have evolved a wide range of molecular programs to sense environmental changes and adapt accordingly to suboptimal growing conditions. A number of studies have been conducted to understand the physiological, cellular, and molecular changes in plants in response to drought stress. For example, plants undergo genetic programming for early flowering and accelerated senescence in response to water-deficit stress. Though this has a been natural mechanism for survival under harsh conditions, it has a detrimental effect on productivity and yield in agricultural crops. From an agricultural standpoint, overcoming programmed cell death is a major hurdle in creating drought tolerant crops with minimal yield loss. One approach is to either overcome or suppress this abiotic-stress induced programmed cell death. Here, we describe the effects of using genetic engineering to supress cytokinin biosynthesis and programmed cell death and resulting drought tolerance phenotype of the transgenic cotton plants.

Technical Abstract: Water-deficit stress is a major environmental factor that limits agricultural productivity worldwide. Recent episodes of extreme drought have severely affected cotton production in the Southwestern USA. There is a pressing need to develop cotton varieties with improved tolerance to water-deficit stress for sustainable production in water-limited regions. One approach to engineer drought tolerance is by delaying drought-induced senescence via up-regulation of cytokinin biosynthesis. The isopentenyltransferase gene (IPT) that encodes a rate limiting enzyme in cytokinin biosynthesis, under the control of a water-deficit responsive and maturation specific promoter PSARK was introduced into cotton and the performance of the PSARK::IPT transgenic cotton plants was analyzed in the greenhouse and growth chamber conditions. The data indicate that PSARK::IPT-transgenic cotton plants displayed delayed senescence under water deficit conditions in the greenhouse. These plants produced more root and shoot biomass, dropped fewer flowers, maintained higher chlorophyll content, and higher photosynthetic rates under reduced irrigation conditions in comparison to wild-type and segregated non-transgenic lines. Furthermore, PSARK::IPT-transgenic cotton plants grown in growth chamber condition also displayed greater drought tolerance. These results indicate that water-deficit induced expression of an isopentenyltransferase gene in cotton could significantly improve drought tolerance.