Evaluation of morphological and chemical characteristics and micropropagation of traditionally grown domesticated apple varieties in Croatia

Abstract

Traditionally grown domesticated apple varieties are known for their adaptability to different climates and a wide range of soil types, and some for resistance to the main diseases. Their evaluation and preservation are very important, not only for restoration of traditional orchards, but also as a source of genetic material for breeding new varieties. Micropropagation of the most valuable varieties could be a way to propagate plants for restoration of traditional orchards, or as a prerequisite for ex situ long-term conservation through cryopreservation. Fruit samples were taken from trees 50 or more years old, of 13 traditionally grown domesticated apple varieties in Bjelovar Bilogora County in Croatia. Morphological traits of the fruits were evaluated during 3 years, and chemical characteristics (soluble solids, reducing sugars, acids and total phenol content) were evaluated during one vegetation year. Tissue culture was established from shoot apices approximately 1 mm in size isolated from buds of 1-year-old scion woods. Axillary branching was induced from two types of explants on MS medium with the addition of 2% glucose, 1% sucrose, 0.1 g*L −1 myo-inositol, 0.8% agar, 0.2 mg*L −1 gibberelic acid (GA3), 0.1 mg*L −1 indole-3-butyric acid (IBA) and 1.5 mg*L −1 6-benzylaminopurine (BAP) in proliferation medium 1 (PM1) or 2 mg*L −1 zeatin (ZEA) in proliferation medium 2 (PM2). The morphological characteristics of the traditionally grown domesticated apple varieties mentioned were not different from their standard values. Average fruit weight (AFW), average fruit height (AFH) and average fruit diameter (AFD) were less than standard values, which can be explained by the age of the fruit trees. Principal component analysis of these traditionally grown domesticated apple varieties showed that fruit Original scientific paper

Optimizing Micropropagation of Apple (Malus × Domestica Borkh) and in Vitro Root Induction By Piriformospora indica

“…In vitro micropropagation of plants is the only method to produce large numbers of pathogen-free plant material in a relatively short period of time. There are many reports on successful methods for apple micropropagation (Batelja Lodeta et al 2019;Bhattacharya & Singh 2018;Kaur et al 2018;Geng et al 2015;Jafarkhani Kermani et al 2009). Since different factors such as genotype and conditions before and during the regeneration process amongst plant growth regulators (PGRs), and culture media influence stages of in vitro propagation of plants, therefore, optimizing different stages of micropropagation are essential in a successful protocol.…”