Effect of GA3 treatments and sowing conditions on ex situ seed germination of Oroxylum indicum (L) Benth. Ex Kurz: A threatened high value medicinal plant

Abstract

The objective of this study was to observe the effect of pre-sowing treatments of gibberellic acid (GA 3 ) and different sowing conditions on ex situ seed germination of Oroxylum indicum. For this, after pre-sowing treatments, seeds were subjected to three different conditions for their germination. Results revealed that only GA 3 treatments have no significantly different (P < 0.5) influence, on seed germination, to control. However, sowing conditions have significant (P < 0.5) influences on seed germination, and condition i (in vitro) found most suitable for the seed germination. Further, the synergistic influence of treatments and sowing conditions significantly (P < 0.5) enhanced the germinationwith rate. The 100 ± 00% seed germination within 7.92 ± 0.58 days having 10.5 ± 0.76 cm seedling height, and 1050 ± 76.38 seedling vigor was recorded in seeds treated with 50 µM GA 3 for 24h and placed under condition (i). Well-developed seedlings were planted in the departmental garden with 90% survival rate. This effort will be helpful for the conservation of this endangered and high-value medicinal tree through ex situ reforestation programs, and to harness its potential sustainably.