Effects Of Temperature And Plant Traits On Seed Germination In Plants In An Alpine Meadow

Seeds play a central role in sexual reproduction among plants.Seed germination is the most early and basic event in plant life cycle.For efficacious flowering and fruiting of plants,it is vital for seeds to germinate in the right time and place.Previous studies on this subject focused on the family and genus level,but more recent studies have paid more attention to the behavior of seed germination at the community level.In the present study,64 species of plant seeds from an alpine meadow community in Hengduan Mountains were used as experimental materials.The responses of seed germination to seasonal temperature variations were compared among plant taxon of different life forms,flowering time,dormancy type,seed weight and seed shape.The findings are as follows:1.There was significant interaction between plant life form and temperature on seed germination(germination rate,p<0.001***;mean germination time,p<0.001***).Perennial plants have a higher germination rate and a wider optimum temperature range,but seeds of annual and biennial plants germinate rapidly in earlier season.2.There was significant interaction between flowering time and temperature on seed germination(germination rate,p<0.001***;mean germination time,p<0.001***).The germination rate of early flowering plants was significantly lower than that middle flowering plants and late flowering plants,and the germination time of early flowering plants was also later.3.There was significant interaction between seed dormancy type and temperature on seed germination(germination rate,p<0.001***;mean germination time,p<0.001***).Seeds without dormancy have higher germination rate and shorter germination time than those with dormancy.4.The seed weight and temperature only had significant interaction on the seed germination rate(p<0.001***).Seeds with lighter mass are more sensitive to temperature fluctuations,and their germination rate change more sharply with temperature fluctuations.5.The seed shape and temperature only had significant interaction on the seed germination rate(p<0.001***).The germination rate of oval and slender seeds was higher than that of nearly round seeds.Our results revealed that the general pattern of plant seed germination in alpine meadow community.The results showed the influence of temperature on seed germination of alpine meadow plants is linked to the traits of plants.There is variability in response to seasonal temperature changes among different taxa of plants.This study helps to deepen our understanding of seasonal temperature changes on population dynamics,community structure and biodiversity maintenance.In addition,this study provides a knowledge for seed germination in alpine meadow communities in Hengduan Mountainous Area,which can provide data support for vegetation restoration in this area.