107 Silver Thiosulfate (STS) Alone and in Combination with Gibberellic Acid (GA3) in the Forcing Solution Influences Budbreak and Shoot Elongation of Dormant Woody Plant Species

Abstract

Research was conducted to further modify the forcing solution system in order to expedite the propagation of woody plants, such as Spiraea canescens, Lonicera maakii, and Cornus alba. Time of immersion in solutions containing 5 mM silver thiosulfate (STS) was compared with the basic forcing solution reported by Yang and Read (1989), a solution containing 200 mg 8-hydroxyquinoline citrate per liter and 2% sucrose. Other treatments employed were gibberellic acid (GA3) 50 mg per liter for 24 h and a combination of STS and GA3 for the same amount of time. Increasing the time in STS solution up to 24 h led to higher percent budbreak and shorter time to budbreak for all the three species examined. The combination of STS and GA3 was the most effective treatment overall in reducing time of budbreak and increasing percent of budbreak. All STS treatments studied showed similar responses in shoot elongation. However, treatments with GA3 alone, and in combination with STS showed more than a doubling in shoot length compared to all STS treatments studied and the control. Implications based on SEM observations will be presented.