ORIGINAL PAPER Aminoethoxyvinylglycine (AVG) ameliorates waterlogging- induced damage in cotton by inhibiting ethylene synthesis and sustaining photosynthetic capacity Ullah Najeeb • Brian J. Atwell • Michael P. Bange • Daniel K. Y. Tan Received: 1 September 2014 / Accepted: 7 February 2015 / Published online: 15 February 2015 Ó Springer Science+Business Media Dordrecht 2015 Abstract In this glasshouse study, we investigated the mechanisms of aminoethoxyvinylglycine (AVG)-induced waterlogging tolerance in cotton. Two cotton cultivars Si- cot 71BRF (moderately waterlogging tolerant) and LA 887 (waterlogging sensitive) were grown in a clay-loam soil, and exposed to waterlogging at early squaring stage (53 days after sowing). One day prior to waterlogging, shoots were sprayed with AVG (ReTain Ò , 830 ppm). Continuous waterlogging for 2 weeks accelerated the shedding of leaves and fruits. As the duration of water- logging increased, shoot growth rate, biomass accumula- tion, photosynthesis (P n ) and stomatal conductance (g s ) were all reduced. Growth of LA 887 was more severely impaired than Sicot 71BRF, with a decline in leaf P n and g s after just 4 h of waterlogging. Waterlogging inhibited al- location of nitrogen (N) to the youngest fully expanded leaves, photosynthesis and biomass accumulation, while it accelerated ethylene production promoting leaf and fruit abscission. AVG blocked ethylene accumulation in leaves and subsequently improved leaf growth, N acquisition and photosynthetic parameters. In addition, AVG enhanced fruit production of both cotton cultivars under waterlogged and non-waterlogged conditions. Higher ethylene production in cotton is linked with fruit abscission, im- plying that AVG-induced ethylene inhibition could poten- tially limit yield losses in waterlogged cotton. Keywords Ethylene  Fruit shedding  Leaf wilting  Nutrient acquisition  Photosynthesis  Waterlogging Abbreviations ACC 1-Aminocyclopropane-1-carboxylic acid AVG Aminoethoxyvinylglycine DAS Days after sowing DAW Day of waterlogging FID Flame ionisation detector g s Stomatal conductance LAR Leaf area ratio LWC Leaf water content N area Nitrogen concentration per unit leaf area NWL Non-waterlogged PAM Pulse-amplitude modulated PAR Photosynthetically active radiation P n Rate of photosynthesis Post-WL Post waterlogging SLA Specific leaf area TDM Total plant dry biomass WL Waterlogged Introduction Excessive water content in soil (waterlogging) is a major constraint to crop production in many irrigated parts of the world including Pakistan, India and China (Crosson and Anderson 1992). In Australia, waterlogging-induced annual U. Najeeb (&)  B. J. Atwell  M. P. Bange  D. K. Y. Tan Department of Plant and Food Sciences, Faculty of Agriculture and Environment, The University of Sydney, Sydney, NSW 2006, Australia e-mail: najeeb.ullah@sydney.edu.au B. J. Atwell Department of Biological Food Sciences, Faculty of Science, Macquarie University, Sydney, NSW 2109, Australia M. P. Bange CSIRO Agriculture Flagship, Australian Cotton Research Institute, Narrabri, NSW 2390, Australia 123 Plant Growth Regul (2015) 76:83–98 DOI 10.1007/s10725-015-0037-y