The phenomenon of heterogeneity in the state of seed dormancy

Abstract

Developed as an adaptive strategy, the phenomenon of seed dormancy retained the ability to evolve and can change along with the changes in environmental conditions (temperature, humidity, light, availability of nutrients). Seed dormancy is the center of the so-called “thermal memory”, playing a key role in the acclimatization of plants to the seasonal climate. By saving information about the past temperature conditions of the species existence, the seeds manifest a high degree of heterogeneity in depth and type of dormancy, which varies depending on the location of the seed in the fruit and the fruit on the inflorescence, seed size, altitude and latitudinal areal of plant populations, weather conditions for seed maturation and preservation in soil. The high degree of plasticity of dormancy state requires different approaches to the study of this problem. In this regard, the article gives a number of recommendations for carrying out experiments and using special methods. One should take into account the areal of the species, the weather conditions for seed maturation and the periods of seed dry storage. Factors such as temperature and illumination should be applied in a differentiated way that permit to reveal the individual mechanisms of the initiation and removal of dormancy. The use of different methods -monitoring of seed germination, the culture of isolated embryos, cytoembryological study - makes it possible to assess the internal state of the seed and the localization of the mechanism of inhibition of post-development and germination of the embryo.