Effect of medium composition, genotype and age of explant on the regeneration of hexaploid plants from endosperm culture of tetraploid kiwiberry (Actinidia arguta)

Abstract

Endosperm, an ephemeral and storage tissue, serves as a source of nutrition and protection during embryo development and germination. It can be used for the cultivation of polyploid plants in vitro. Here, results of plant regeneration and acclimatization from the endosperm-derived calli of four cultivars of Actinidia arguta has been presented. Seeds excised from fresh fruit and dry seeds stored for one year served as the sources of endosperm explants of selected tetraploid cultivars of A. arguta. Callus Induction Medium (CIM; containing 0.25, 0.5, or 1 mg/l of TDZ) and Actinidia Endosperm Medium (AEM; containing 2 mg/l of 2,4-D and 5 mg/l of kinetin) were used to study the organogenic responses of the calli. On AEM, the source of explant did not significantly affect the rate of callus induction for any of the tested cultivars; no organogenic events were observed. In contrast, on CIM both the source of explants and the cultivar origin caused significant differences in callus formation and subsequent organogenic events. Histological and ultrastructural analyses revealed the adventitious nature of shoot bud formation on these media. The most efficient elongation of shoot buds was achieved after transferring organogenic calli with adventitious shoot buds to a medium supplemented with zeatin or meta-topolin. Robust root induction with minimal basal callus formation occurred on the medium with indole-3-acetic acid. Flow cytometric analysis revealed that the nuclear DNA content in the leaves of some regenerants was approximately 50 % higher (4.5 pg/2C) than that in leaves from the tetraploid seedlings (3.1 pg/2C),which confirmed that those regenerants originated from the endosperm. The regeneration of such hexaploid plants was more efficient when endosperm from fresh seeds served as an explant; therefore, fresh rather than dry seeds are recommended for endosperm-derived plant production. The hexaploid plants of A. arguta can serve as an important source of breeding material.

Artificial Neural Networks Elucidated the Essential Role of Mineral Nutrients versus Vitamins and Plant Growth Regulators in Achieving Healthy Micropropagated Plants

“…Plant Growth Regulators (PGRs) are vital organic compounds synthesized by plants, which play an essential role in their differentiation and development at low concentrations [ 23 , 24 ]. The addition of suitable PGRs to the culture media has been effective in regenerating kiwiberry shoots [ 25 ]. It is widely accepted that their addition is required for successful shoot initiation and subsequent proliferation [ 26 , 27 ].…”

The appearance of amyloplasts as one of the features distinguishing the initial stages of the development of isolated endosperm in kiwiberry

“…Our previous observations (Abdullah et al, 2021) showed that isolated endosperm in kiwiberry cv. Bingo cultured on NOCIM and supplemented with 2,4-dichlorophenoxy-acetic acid (2,4-D) and kinetin resulted in callus induction with cell proliferation only, with no organogenic events like adventitious shoot or root formation, even aer six months of culturing.…”

“…In addition, there is no evidence that the fate of endosperm changes under natural conditions. Regardless, we have established a protocol for callus proliferation and shoot induction in the isolated endosperm of the kiwiberry, Actinidia arguta (Abdullah et al, 2021;Popielarska-Konieczna et al, 2020), which is a breakthrough result in terms of dealing with recalcitrant (to dedifferentiation) tissues.…”

Effect of bleeding to Actinidia arguta (Sieb. & Zucc) Planch. ex Miq. on plant growth, physiological characteristics and fruit quality

“…Additionally, its edible and distinctive avor fruit has high content of vitamin C, abundant nutritious substances and medicinal usage, and was considered as one of the most nutritious fruits [5][6][7]. For its edible peel, the bright fruit color, the majority of consumers love this fruit, people are aware of the health bene ts associated with consuming A. arguta [8,9]. And it also has many horticultural advantages over the common A. arguta, due to high frost resistance [10].…”