A study of the ontogenesis of early-maturing walnut cultivars in Voronezh

A.N. Odintsov, V.F. Shipilova, V.D. Dorofeeva, O.V. Komarova
Recently, much attention has been paid to early-maturing or neotenic forms of walnut (Juglans regia L.), which start to bear nuts at the age of 2-3 years, while for ordinary forms it takes 8-12 years. The seed reproduction of walnut has a number of advantages, since plants adapt to the given conditions from the beginning and later they are more stable, tolerant and drought-resistant. The purpose of this work was to study the ontogenetic development of early-maturing walnut grown from seeds. The study was based on 'Ideal' cultivar (the breeder - E.V. Evangelista). In the research, we studied fruit characteristics: the average size of the nut was 38.6×34.0 mm, the fruit body had a slightly ridged surface, the shell was 0.9 mm thick. 100 nuts weighed 1.0-1.2 kg. After snow stratification, 200 nuts were sown on the trial plot in the forest nursery of All-Russian Research Institute of Forest Genetics, Breeding and Biotechnology, Voronezh. When monitoring the seedlings, we identified the following ontogenetic stages of walnut: latent period (seeds); pre-generative period (seed germination and seedling growth) and generative (fruiting phase). Shoots appeared after 10-12 days. Radicles of the embryo formed tapering main roots. Vegetative growth ended in the middle of June with the formation of buds. Fruiting shoots had two growth cycles: the spring one ended in June and the summer one NDASH in August. The generative phase of ontogenesis began in May next year, when the average height of the plant was 14-16 cm and 40% of them formed flowers. In September that year, the first nuts were produced. This indicates that the acclimatization process described was successful and the cultivar can be recommended for the establishment of early-maturing walnut plantations in the Central Black Earth Region.
Odintsov, A.N., Shipilova, V.F., Dorofeeva, V.D. and Komarova, O.V. (2021). A study of the ontogenesis of early-maturing walnut cultivars in Voronezh. Acta Hortic. 1324, 285-290
DOI: 10.17660/ActaHortic.2021.1324.44
Juglans regia, neoteny, ontogenetic phases, flowering, fruiting

Acta Horticulturae