Over-expression of tomato fructokinase (LeFRK1) in cotton enhances yield

Authors: MUKHERJEE, THIYA - Texas Tech University; Gitz, Dennis; Payton, Paxton; KANAYAMA, YOSHINORI - Tohoku University; GRANOT, DAVID - Volcani Center (ARO); HOLADAY, SCOTT - Texas Tech University

Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/27/2018
Publication Date: 11/30/2018
Citation: Mukherjee, T., Gitz, D.C., Payton, P.R., Kanayama, Y., Granot, D., Holaday, S. 2018. Over-expression of tomato fructokinase (LeFRK1) in cotton enhances yield. Journal of Cotton Science. 22:183-190.

Interpretive Summary: Sustainable agriculture depends upon maintaining production while reducing or even eliminating dependence on non-renewable resources. Though molecular biologists have developed plants with traits such as those associated with resistance to insect damage or herbicide resistance, no single gene has been identified that is associated with drought tolerance. Maintaining yield under drought stress is important because precipitation is seldom optimal in the southwestern United States and irrigation waters are being depleted. Scientists from ARS (Lubbock, Texas, Texas Tech University, Tohoku University (Japan) and the Volcani Center (Israel) inserted a gene from tomatoes into cotton plants. Cotton plants altered with the tomato gene continued to use sunlight to make food under conditions where the normal plants had stopped making food. Over the course of a preliminary small scale pilot study, cotton yield was increased by 80%. These results suggested that this approach could result in traits to sustain or even improve cotton yield under mild droughty conditions typical of the southwestern United States.

Technical Abstract: Efforts to identify and introduce single genes that could maintain or increase cotton production in water limited production settings have resulted in extremely limited success. The primary objective of this investigation was to test whether over-expression of the tomato fructokinase gene, LeFRK1, in field grown cotton could improve fiber yield under variable growth conditions and contrasting irrigation levels in warm semi-arid environments characteristic of the southern high plains. A secondary goal was to determine whether a larger field scale experiment might be justified based upon the results of this exploratory work. Cotton over-expressing LeFRK1 was field grown in small plots over three years under irrigation, contrasting irrigation levels, or without irrigation. Increased yield was found when comparing all LeFRK1 lines relative to that of the control line, though seasonal and plant to plant variability limited confidence in extension of the results to the production scale. We hypothesized that yield improvements resulted from a suite of responses arising from increased availability of photosynthate at the leaf to the whole plant level to developing fruits. The results suggested that LeFRK1 over-expression might be a viable approach to improving cotton yield in warm semi-arid environments characteristic of the southwestern U.S., though field trials are needed to confirm these findings.