Gibberellic Acid Effect on Growth and Flowering of Ajania Pacifica /Nakai/ Bremer et Humphries

Abstract

The research addressed the effect of gibberellic acid (GA 3 ) on growth and flowering of Ajania pacifica /Nakai/ Bremer et Humphries ‘Bea’. The vegetative growth lasted for 8 weeks in glasshouse, under natural long day and from August 15 - under natural short day. The plants were divided into four groups: 1 - the plants sprayed with distilled water (control combination); 2, 3 and 4 - the plants sprayed with GA3 ones, twice and thrice, respectively, starting from the 5 th week of growth, and then in the 6 th and 7 th week, successively. Each of the group was divided into two subgroups: the first one treated with GA 3 at concentration of 250 mg·dm -3 and the second with 500 mg·dm -3 . It was observed that double spraying with GA 3 accelerated the buds development of Ajania pacifica, thus shortened the cultivation time by about two days. Treatment with GA 3 at concentration 500 mg·dm -3 stimulated the elongation of shoots more than treatment with GA 3 at 250 mg·dm -3 . The plants sprayed twice were longer than the control and then those sprayed one time. However, elongation of shoots was not remarkable; corymbs were shorter, narrower, and contained lesser number of inflorescences. The present study indicates the specificity of the response of Ajania pacifica to GA 3 treatment, which appears to be different from other ornamental species.