Rooting green cuttings of Altai seabuckthorn cultivars in industrial-scale experiment

Green cutting propagation technologies of seabuckthorn ( Hippophae rhamnoides L.) are well developed and highly effective under optimal parameters of implementation. Differences in root development in most cases are connected with varietal specificity. In conditions of uncovered greenhouses, weather particularities can influence significantly on development of cuttings. Hence, the aim of investigation was to study the cultivar difference in root development of seabuckthorn green cuttings in a long-term industrial-scale experiment in conditions of uncovered greenhouse facilities. The experiments were carried out in forest-steppe area of Altai krai in 2018-2021. Seventeen seabuckthorn cultivars developed by Federal Altai Scientific Center of Agrobiotechnologies were taken as research objects. Significant varietal specificity of rooting ability of green cuttings has been established. The experiments showed that season particularities just slightly affect this parameter, indicating significant homeostasis of seabuckthorn cultivars in this regard. Altaiskaya, Ognivo, Gnom, Ethna, Elizaveta and Athena varieties showed the highest level of rhizogenesis with everage rooting percentage from 91.2 to 95.5 %. Group of low rooted cultivars included Azhurnaya, Aurelia, Zlata, Sudarushka and Avgustina with rooting percentage from 70.5 to 79.7 %. Other cultivars showed intermediate figures. High correlation level (0.59±0.21) was shown between total root quality and rhizogenesis ability. Cultivars which demonstrated high rooting percentage also formed high level of first grade seedlings. In this regard, the best cultivars were Altaiskaya, Gnom and Ognivo, which formed 79.1, 82.1 and 83.8 % of first-grade seedlings, respectively. Low rooting ability was observed in cultivars Avgustina, Sudarushka and Zlata, which provided only 55.4…64.4 % of first-grade planting material. The variation coefficient of seabuckthorn standard seedlings was low and did not exceed 9.7 % for Avgustina cultivar. The variation of seedlings quality was at a higher level - u p to 27.3 % for cv. Sudarushka, however, for the rest of the cultivars it was low or medium and ranged from 2.7 to 18.7 %. According to the results of cluster analysis, the seabuckthorn cultivars were divided into three separate groups - slow-, medium- and fast-to-root genotypes.