3.1 Description of Lithuanian potato varieties
Potato varieties ‘VB Venta’, ‘Goda’, ‘VB Liepa’, ‘VB Meda’, ‘VB Rasa’ and ‘VB Aista’ main features description is presented in the Table 1. In this table are presented the main potato characters used for potato varieties description.
Very early is the potato variety ‘VB Venta’ from 2009. Round tubules with moderately profound eyes were present. The flesh and epidermis were both a light-yellow color. This cultivar is a salad variety. It produces 29.9 ± 0.88 t ha-1 of potatoes. 15.2 ± 0.65 is the starch concentration (%). The R01 phenotype of golden worms, a resistant potato cyst nematode.
Early is the potato variety ‘Goda’ (2004). The tubules are middle in size, oval, round, and have shallow eyes. The skin and flesh were a light-yellow hue. The cultivar of potatoes produces 37.2 ± 1.21 t ha-1. The percentage of starch is 17.5 ± 0.61. The R01 phenotype of golden worms, a resistant potato cyst nematode.
Early is the potato variety ‘VB Liepa’ (2010). The plants are small and have violet blooms. The eyes of the medium-sized, round bulbs are shallow. The skin and flesh were a light-yellow hue. The cultivar of potatoes produces 31.3 ± 0.92 t ha-1. 18.6 ± 0.71 is the starch amount (%). The golden worm R01 phenotype of the resistant potato cyst nematode.
The medium ‘VB Meda’ potato variety (2019). The plant was middling in size and fairly compact. The flower had a brief flowering phase and was white. Potato tubers have rough surfaces, yellow epidermis, yellow innards, and oval, shallow eyes. The cultivar of potatoes produces 35.8 ± 1.07 t ha-1, 17.4 ± 0.68 is the starch amount (%). The golden worm R01 phenotype of the resistant potato cyst nematode.
‘VB Rasa’, a potato variety from 2006, is late. The plants are small and have violet blooms. The cultivar of potatoes produces 26.6 ± 0.74 t ha-1. The percentage of starch is 19.5 ± 0.87. The R01 phenotype of golden worms, a resistant potato cyst nematode.
Very late is the potato variety ‘VB Aista’ (2006). The stems of the shrub were tall and the bush was stretched out. The medium-sized, white blossoms were in bloom. This cultivar blooms profusely and continuously. The tubers had shallow eyes, were big, yellowish, flat, and round. The cultivar of potatoes produces 30.4 ± 0.84 t ha-1. The starch concentration is 20.6 ± 0.97 in percentage. The R01 phenotype of golden worms, a resistant potato cyst nematode.
3.2 Genetic diversity of Lithuanian potato varieties
When evaluating the results of the SSR satellite DNA analysis of Lithuanian varieties, the informativeness of the test loci was first determined. It was high enough for all loci to be 0.72–0.85, except for ST142, for which PIC=0.67 (Table 4). On average 7.5 alleles were obtained at each locus. The highest number of alleles was found at the STM1106 locus (10) and the highest number of polymorphic alleles was found at STM0030 (8 of 9). According to the results of the cluster analysis of the nearest neighbors, all Lithuanian varieties except ‘VB Liepa’ and ‘VB Aista’ formed a separate phylogenetic subgroup, but its reliability value was less than 50 % (Fig. 1). Analysis of the principal components showed that the data of the individual varieties tended to cluster, and the Lithuanian varieties were divided into four subgroups. First subgroup mentioned above, and the second include ‘VB Venta’, ‘Goda’, third ‘VB Meda’, and the last subgroup is left with one variety ‘VB Rasa’ (Fig. 1). After evaluating the genetic distances between the varieties, it was found that distances between varieties ranged from 0.55 to 0.92, indicating moderate heterogeneity (Table 5). The greatest genetic distance is between ‘VB Liepa’ and ‘VB Rasa’ (0.92) and between ‘VB Liepa’ and ‘Goda’ (0.90) (Table 5).
3.3 Evaluation and choice of potato varieties of Lithuanian breeding to wart causative agent Synchytrium endobioticum
By the study’s results, the following 6 varieties of Lithuanian breeding (‘VB Venta’, ‘Goda’, ‘VB Liepa’, ‘VB Meda’, ‘VB Rasа’ and ‘VB Aista’) among 6 testing varieties for evaluation and choice of potato varieties resistant to common pathotype causative agent during 2020-2021. The degree of resistance varied in the scope of 1.6-5.0 points (Table 6). There were no causative agents determined under the field conditions.
The positive control defeating (sensible to potato wart ‘Poliska rozheva’) consisted of 93.3 %. The degree of defeat consisted of 5.0 ± 0.08 points. The negative control (resistant variety ‘Glazurna’) was 0 %. The degree of resistance was one point (Table 6).
‘Poliska rozheva’ potatoes (positive control of potato warts). It obtained from 'Nemichaevska iuvileyna' x 'Perlina' progenitor forms crossing. This is a table type that is mid-late. The oval, crimson tubers were in shape. White skin is present. Red violet blossoms are in bloom. There is a starch content of 17–18%. Warts and late blight don't affect it, but common scab, black rot, and ring rot do. Development ideas are offered for wooded regions. Variety is not entered in the State Registry. The yield is 38 t ha-1.
The potato variety ‘Glazurna’ was created by crossing the progenitor forms ‘Gorlitsa’ and ‘Dobrochin’ and it serves as a negative control for potato wart and late blight. It is a table cultivar that is early. The oval, scarlet tubers are in shape. The blossom crown is a reddish-purple color. 15.7% of the substance is flour. It is very nourishing in nature. It has 1.2 points of resilience to potato wart and late blight (8.2 point). Variety included in the State Registry as of 2010. Woodlands and Step are suggested locations. The yield is 36 t ha-1.
3.4 Evaluation and selection of potato breeds from Lithuania that are immune to Phytophthora infenstans (Mont) de Bary
'Goda’, 'VB Liepa' and 'VB Meda' three Lithuanian-bred potato varieties with notable late blight resilience, were extracted (8.0-8.2 points). Relative resistance to late blight of the potato cultivars ‘VB Aista’, ‘VB Rasa’ and ‘VB Venta’ (7.2–7.4 points) (Table 7). They had 15–25% of their leaf area and tubers infected. The cultivar ‘Nezabudka’ (used as a positive control) had infected tubers and 80% of its leaf surface, The late blight-defeating capacity of the potato cultivar ‘Glazurna’ (for negative control) was 5%.
The ‘Nezabudka’ type of potatoes (positive control to late blight). It obtained from 'Vityazi' x 'Nemichaevska iuvileyna' progenitor forms crossing. It is a table cultivar that is early. The rubbers are small, round, and brightly colored. Cream makes up the body. White blossoms cover them. The amount of carbohydrate is 13.3–15.3%. It is prone to late blight but resistant to potato wart. In the State Registry as of January 2022, there is. The yield is 30 t ha-1.