Physiological, morphological and chemical changes in pea seeds under different storage conditions

The loss of germination, viability, and vigor of seeds under storage conditions are the main causes of the need to multiply the seed material for leguminous crops. For crop establishment, seeds obtained in propagation fields are usually used, and the coating comes from the basic seed. In the case of leguminous species, the seeds quickly lose their viability, and in accordance with international regulations, for legumes, the number of seeds increases only in the first year of propagation. Therefore, the main objective of this study was to assess the effects of variations in the storage period, temperature and humidity on the morphophysiological and chemical traits of two pea seed varieties (Gloriosa and Kelvedon Wonder). The pea seeds were harvested at the end of June 2017, 2018 and 2019 and stored for 32, 20 and 8 months at T = 4 °C and H = 8%; T = 4 °C and H = 12%; T = 8 °C and H = 8%; T = 8 °C and H = 12%; and T = 22 °C and H = 65%. The results of the morphological, chemical, and biochemical analyses showed that the highest germination rate; hypocotyl length; radicle length; lipid content; dietetic fiber content; caloric value; and Ca, Mg, K, Na, Fe and Zn contents were detected in the Gloriosa and KW seeds stored for 8 months at 4 °C and 8% humidity. Analysis of the experimental data by statistical methods revealed that increasing the storage time had an individual significant negative influence only on the germination rate of both pea varieties and on the hypocotyl length and radicle length of the KW variety, while humidity and temperature variation had individual significant influences on the lipid content. The significant effects of humidity and temperature on the germination rate, hypocotyl length and root length of KW plants were also determined. For the remaining morphophysiological and chemical traits of pea seeds, the individual and combined effects of the factors were not statistically significant. Furthermore, the comparison of means using the Tukey test showed that storage conditions related to temperature and humidity generally used by farmers (T = 22 °C × H = 65%) did not significantly affect the majority of the nutritional properties of the pea seeds. However, maintaining pea seeds under these conditions for a longer period of time significantly affects seed germination and vigor.