Germination behavior of several coniferous seeds

Abstract

Seed germination is variously affected by the internal condition of the seed and various external factors. To discuss the testing rule and reasonably to estimate the germination percent under a given condition, we should know the multi-dimensional germination behavior of seeds. On the basis of this idea, several experiments were conducted with some coniferous seeds. The germination of Pinus densiflora seeds is favored with light or under alternating temperatures, but favored much more by stratification. The germination of P. thunbergii seeds is almost completed with light. The germination of Picea polita seeds is favored with light under constant temperature or at alternating temperatures without light, but favored much more by stratification. Picea glehnii seeds behave almost in the same manner as Pinus thunbergii seeds. Their germination is completed with light. The germination of Larix kaempferi seeds seems to be favored mostly by stratification. It is decreased with the oversupply of water. The seed germination of three species in Abies is favored by stratification. The germination of Abies firma stratified seeds is not so affected with light. The germination of Abies mayriana stratified seeds is favored with light, especially under a special combination of temperatures. The germination of Abies mariesii stratified seeds is favored with light except at 25°C. The results reported here indicate that a photo-reaction and thermo-reaction including the reactions occurring during stratification should be geared to each other.