Accumulation and morphological properties of starch in tubers of new potato hybrids

The article presents the results of studying potato accessions according to the accumulation and morphological properties of starch in tubers in the nursery of dynamic testing in agroecological conditions of the Kirov region (Volga-Vyatka region) in 2022. The objects of the research were 11 new hybrids bred by the Falenki Breeding Station – branch of the Federal Agricultural Research Center of the North-East named N.V. Rudnitsky. The early-maturing variety Udacha, the middle-early variety Nevsky, and the mid-season variety Chaika were used as standards. There have been identified hybrids with increased starch content (19 % and higher) on the 80th day of vegetation: early-maturing 172-13, medium-early – 165-00, 27-07, 13-18, mid-season – 182-13, 580-13, 252-18. The hybrids of the middle early group had the largest average size of starch grains: 165-00 (34.3±2.6 microns), 132-18 (36.0±3.0 microns), 233-12 (39.2±3.3 microns). Most of the hybrids had starch grains of regular rounded shape, accessions 233-12 and 232-12 – mostly irregular (angular) shape. In the course of the research, it was found that storing potatoes at the temperature of 3...4 ° C led to a decrease in the fraction of starch grains of very large size: in early-maturing varieties from 9.2 to 2.7 %, in middle early – from 13.5 to 5.0 %, in mid-season – from 9.6 to 3.2 %, which was due to starch resynthesis. As a result of the breeding work, promising potato hybrids of various maturation periods have been identified for transfer to state variety testing with improved agronomic traits, including high potential productivity: early-maturing 172-13, middle-early 233-12, mid-season 182-13 and 580-13

Evalu ation of potato hybrids according to tuber flesh darkening and other useful agronomic characters under the conditions of Kirov Province

Background. Resistance of raw and boiled tuber flesh to darkening when potato is processed into potato-based products or consumed directly is an important requirement for new potato cultivars. Identification of hybrids resistant to tuber flesh darkening would contribute immensely to future breeding work.Materials and methods. Parent forms and hybrid progeny of potato were tested for five years (2016–2020) in Kirov Province using the methods and technologies approved for potato breeding process. The progeny of 10 cultivars used as pollinators was analyzed.Results and conclusions. Cultivars with high levels of resistance to the darkening of raw tuber flesh were selected in the collection nursery. A total of 62 accessions (or 24%) out of 256 were identified for the absence of darkening or only small traces thereof (8 points) in raw tubers. Medium and strong darkening of the flesh (4–5 points) was recorded for 45 accessions. Analyzing the progeny of pollinator cultivars showed an increased occurrence of hybrids resistant to tuber flesh darkening in the progeny of cv. ‘Manifest’: 71% of the studied hybrids had non-darkening flesh (9 points). Manifestation of tuber flesh darkening was found to depend on weather conditions during the growing season: the higher was the air temperature, the weaker was the darkening of raw tuber flesh, but when the soil moisture during tuberization was high, tuber flesh became more darkened. A statistically significant relationship was observed between the darkening of boiled tubers and the content of crude protein (r = 0.74) and vitamin C (r = 0.79). Hybrid 179-10 was identified for high productivity (32.5 t/ha) and crude protein content (1.54%), while the highest resistance to the darkening of raw and boiled potato tubers was registered in hybrid 72-13