Effects of S-ABA On the Physiology and Marketability of Various Container-Grown Taxa During Short-Term Desiccation

Reduced post harvest care of woody plant material in retail settings can decrease the number of days plants remain marketable.  If plants are sold on consignment for growers, reduced sales can lead to poor profitability.  This study investigated the effect of spray applications of s-abscisic acid (s-ABA) (ConTego Pro™, Valent Biosciences Corp.) to increase the number of days of marketability for various woody taxa in a simulated retail setting.  In the first stage of the study, various well-watered container-grown taxa were treated with a spray application of either 0, 1000 or 2000 mg∙L^-1 s-ABA and water was withheld.  Daily, desiccation symptoms were recorded to determine if plants had reached the critical wilting point and thus became unmarketable.  Marketability was increased approximately 2-3 days for plants treated with 2000 mg∙L^-1 s-ABA compared to nontreated plants.  In the second stage, marketability and physiology of Ligustrum japonicum ‘Recurvifolium’ (wavy leaf privet) were monitored after plants were treated with spray applications of 0, 500, 1000, 1500 or 2000 mg∙L^-1 s-ABA. Stomatal conductance (g_s) declined for all plants depending on the concentration applied.  Plants treated with s-ABA had lower g_s rates and remained marketable longer than nontreated plants.  All plants fully recovered to pretreatment g_s rates provided they were rewatered immediately upon reaching the critical wilting point.  Spray applications of s-ABA can increase shelf life of select woody ornamentals.