Adaptation of regenerant plants representing the genus Hydrangea L. to non-sterile conditions using a hydroponic system

Abstract

The adaptation of regenerant plants to ex vitro conditions constitutes the final stage of clonal micropropagation for hydrangea. The study used the AirCube Ebb & Flow hydroponic system that periodically floods the plant roots with a nutrient-rich solution. The study examined the effect of three different substrates on the establishment of regenerant plants: agroperlite, coconut substrate, and mineral wool. The establishment of microshoots with the use of the hydroponic system was found to average 85 %. Agroperlite proved to be the most effective substrate for the adaptation of regenerant plants: the average plant establishment amounted to 90 %; the use of mineral wool was shown to be the least effective (81 %). A greater number of plants with full root system development after 15 days of adaptation was noted with the use of agroperlite and coconut substrate. Of all the studied substrates, agroperlite was more effective for root system development (average root length of 5.9 cm), with the coconut substrate being slightly inferior (average root length of 5.4 cm); the use of mineral wool was the least effective (average length of 2.9 cm). The greatest average plant height at day 30 of cultivation was observed in H. arborescens varieties (8.61 cm), while the lowest was noted in the varieties of H. paniculata (4.02 cm). The use of a hydroponic system in the adaptation of regenerant plants was proved to provide a means to obtain the planting material of hydrangea with a developed above-ground part and root system in 30 days.