Studies On Seed Yield Components And Seed Production Performance Of Five Gramineous Plants

Studies were carried on the seed productions of five gramineous plants. Phenological changes, biological characters, and flowering and seed production behaviours of the five plants were investigated. The analytical quality and physiological quality of seed were assessed in different periods of seed development and in the different storage stages of matured seeds. Seed yield components were analyzed. Potential seeds yields were estimated based on seed yield components and actual seed yields were evaluated.Agropyron desertorum and Leymus chinensis have longer reproductive development period than the other plants, which adds up to more than 50 days. Elymus lanceolantus Critana's has only 33 days of reproductive period. Leymus chinensis blooms in the morning while other plants bloom in the noon. Agropyron desertorum, Elytrigia intermedia and Thinopyrum ponticum bloom beginning from middle-top position of the spike while the rest plants bloom beginning from middle-foot position of the spike.Seed vigor and the thousand seed weight raise gradually with seed development process, while the seed moisture content drop along. Seeds of Leymus chinensis has low germination rate from the beginning to the end in developing process and the initial germination time prolongs continuously and the mature seed of Leymus chinensis can't germinate through long period of storage, which indicates that seeds of Leymus chinensis have dormancy. Final seed germination rates of the other four plants continuously increase and the initial germination time continuously shorten in seed development process, but they need a long time for germinating completely. Meanwhile, the seed germination rate, germination index (GI) and vigor index (VI) of mature seeds progressively raise along with the storage. These all show that the rest four plants have after-ripening characters.The potential seed yields of the five plants are all high by counting the values of seed yield components. The potential seed yield of Leymus chinensis is the lowest, but it can still reach to 4300 kg/km2. Harvested seed yields of Leymus chinensis, Agropyron desertorum and Elymus lanceolantus are not very high because of the factors of few reproductive branches, low seed setting percentage, seed dropping character and plant lodge, etc. The harvested seed yield of Elytrigia intermedia and Thinopyrum ponticum are relatively high.