Micropropagation of rare bryo-halophyte Hennediella heimii

Abstract

The rare moss species Hennediella heimii (Pottiaceae) was established in in vitro culture. Various treatments were tested to achieve axenical cultures. The most effective sterilising procedure was NaDCC treatment of sporophytes, keeping the spore viability and giving high disposal of xenic cohabiting organisms. The effects of plant growth regulators were studied regarding new shoot formation, i.e. bud formation on the protonemal filaments and protonemal patch size. Low concentrations of cytokinin and medium concentrations of auxin are shown to increase protonemal patch size and shoot production. Multiplication of H. heimii was observed to occur spontaneously on BCD medium type, but to achieve better and rapid biomass production and development it is suggested to grow it on a BCD medium enriched with auxin and cytokinin combined.

An Insight into the Biology of the Rare and Peculiar Moss Pterygoneurum sibiricum (Pottiaceae): A Conservation Physiology Approach

“…Moreover, higher concentrations of IBA and BAP led to a reduction in the protonemal patch diameter, suggesting that high concentrations of growth regulators demonstrated inhibitory effects on protonemal patch diameter. A similar pattern was previously documented for H. heimii [ 46 ] and B. argenteum [ 59 ], where the critical concentration of IBA was 0.1 µM. The plants grown on media supplemented with low concentrations of BAP (0.1 µM) developed slightly smaller protonemal patches than the control plants and those grown on media supplemented with 0.1 µM IBA ( Figure 3 B).…”

“…In contrast, high concentrations of cytokinins often induce the development of abnormal gametophores and a small number of new buds and shoots [ 52 ]. This was also proven for H. heimii when 10 µM BAP was used [ 46 ], as well as for B. argenteum [ 59 ]. Moreover, in this study, when combined with IBA, concentrations of BAP higher than 0.1 µM had negative effects on the formation of new shoots ( Figure 3 A).…”

“…Previous research has also shown that certain types of nutrient media are more suitable for the propagation of mosses in vitro and that some species often prefer solid nutrient media free of sugars or growth regulators [ 39 , 44 , 45 , 46 ]. However, low concentrations of exogenously added sucrose or NaCl to BCD or KNOP media for shorter periods can contribute to the improved multiplication and regeneration of some tested species, such as bryo-halophyte Hennediella heimii (Hedw.)…”

“…However, low concentrations of exogenously added sucrose or NaCl to BCD or KNOP media for shorter periods can contribute to the improved multiplication and regeneration of some tested species, such as bryo-halophyte Hennediella heimii (Hedw.) R. H. Zander [ 46 , 47 , 48 ]. In general, sugars such as sucrose, fructose, and glucose have essential functions in plant metabolism [ 49 ] but do not necessarily contribute to the increase in IM and improved growth of mosses [ 45 ] since bryophytes are rather successful in autotrophic culture systems compared to vascular plants (photomixotrophic metabolism in culture) [ 50 ].…”

“…Some moss species spontaneously form a large number of new shoots in axenic conditions, such as model moss Physcomitrium patens (Hedw.) Mitt., while others need the presence of growth regulators or sugars in the nutrient media or some other stimuli for bud induction, e.g., [ 46 , 54 , 55 ]. Previous studies have described the effects of auxin and cytokinin on morphogenesis in bryophytes.…”