Silver thiosulfate alone and in combination with gibberellic acid in the forcing solution influenced bud break and shoot elongation of dormant woody plant species

الملخص EN

Experiments were conducted to further modify the forcing solution system developed by Read et al.

(1984) in order to expedite the propagation of woody plants, such as Spiraea canescens, Lonicera maackii and Cornus alba.

Four different immersion times were used with 5 mM silver thiosulfate (STS) alone, with the basic forcing solution (200 mg 8-hydroxyquinoline citrate/1 and 2% sucrose) used as a control.

Two other treatments employed 50 mg gibberellic acid (GA3)/l for 24 hr and a combination treatment of 50 mg GA3/l followed by 5 mM STS for 24 hr each.

Adding STS to the basic forcing solution led to higher percent bud break and shorter time to bud break for all three species examined.

The combination treatment of GA3 and STS was the most effective treatment overall in reducing time to bud break and increasing percent bud break.

All STS treatments studied showed positive responses in terms of shoot elongation of forced new softwood growth.

However, the combination of GA3 and STS exhibited more than a doubling in shoot length compared to all treatments studied, including the control treatment.

A scanning electron microscopy study of the stems receiving different forcing treatments suggests that the use of certain chemicals can mobilize stored starch to enhance the growth rate of softwood shoots from forced woody stems.

Stems from which the samples were collected apparently utilized the stored starch grains during the breakdown of the dormant period and for subsequent shoot elongation.