Fruit growing
and viticulture of South Russia

Annotation

To optimize the conditions of a slowly growing culture, of considerable interest is the study of the effectiveness of introducing the various growth inhibitors (osmotics, etc.) and cations, in particular calcium, into nutrient media. In this regard, the goal was � to identify the effect of calcium and mannitol the physiological and biochemical parameters of large-leaved hydrangea in a slow-growing in vitro culture. The results of a study to optimize the cultivation of large-leaved hydrangea (Hydrangea macrophylla Ser.) in a slow-growing in vitro culture are presented. We studied the effect of various concentrations of calcium (440-660-880 mg/L) under osmotic stress, which was modeled by the introduction of mannitol at a concentration of 40 g/L in a nutrient medium. The morphometric parameters of the plants were estimated as the height of the microshoots, the number of leaves on the microshoot, the number of internodes, the number of roots, the length of the roots, the relative electrical conductivity of the leaves, and the content of free proline. The results of the studies showed the possibility of non-stop preservation in culture in vitro for 4-8 months of microshoots and microplants of large-leaved hydrangea. The experiments revealed the ability of plants studied to reduce the kinetics of growth and maintain viability at elevated concentrations of calcium in the nutrient medium (CaCl2 660 and 880 mg/L). It is shown that the addition of mannitol at a concentration of 40 g/L to the nutrient medium caused a strong osmotic stress in hydrangea regenerant plants (with prolonged cultivation), leading to inhibition of plant growth and development, decrease in cell membrane stability and accumulation of free proline. Under conditions of osmotic stress, an increase in the concentration of calcium in the nutrient medium contributed to a more intensive accumulation of free proline, which increased in the stability of microprobe.