Dynamics of tuber weight in early potato varieties in the contrasting weather conditions of the Northwestern Russia
¹N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR), 42, 44, Bolshaya Morskaya Str., RU190000 St. Petersburg, Russia
²St. Petersburg State Agrarian University, Building A, 2, Peterburgskoe shosse, Pushkin, RU196601 St. Petersburg, Russia
Under climate changes, it is particularly important to search for characteristics of varieties that are steady in contrasting weather conditions. The aim of the present research was to study the relationship between the growth of tubers and haulms in early potato varieties in the Northwestern Russia. Fourteen early potato varieties were studied in the field experiments conducted in 2017–2019 in the vicinities of St. Petersburg. The results of three intermediate digs on the 45th, 60th and 75th day from the planting date were analyzed. The correlation analysis, ANOVA, and regression were used. The average haulm and tubers weight significantly differed in the years of the study, while the number of tubers per plant and the haulm to tubers weight ratio did not differ. The relative growth rate of tubers weight from day 45 to 60 and from 60 to 75 did not differ significantly between 2018 and 2019, the years contrasting in terms of weather conditions. On the average, the tubers weight increased 2.6–2.8 times from day 45 to 60, and 1.4 times from day 60 to 75. It has been established that the early prediction of productivity in early potato varieties can be based on the haulm weight on the 60th day after planting; its coefficient of correlation with productivity was 0.72–0.79. Every 100 grams of the haulm weight on day 60 ensures a 100–200 g increment in the tubers weight by the time of harvest on day 80. The obtained results can be used in the development of a morphometric indicator-based automated system for monitoring the growth of potato plants.