What are the reproductive characteristics of Leymus chinensis?

Leymus chinensis is a cross-pollinated plant. According to the opening mode of flowers and the characteristics of wind-blown flowers, Leymus chinensis is determined to be wind-blown flowers. Before the flowering of Leymus chinensis, the whole spike is slack, the spikelet is swollen, the palea is open, the anther is elongated and drooping, and then the stigma is elongated from the neck to both sides, showing a split feather shape. After about 2 hours, the anthers gradually withered, changed from orange to yellow, the palea closed and the flowering ended. After flowering and pollination of Leymus chinensis seeds,15 ~ 20 days reached milk maturity, 25 ~ 30 days reached wax maturity and 30 ~ 35 days reached full maturity. According to the investigation of seed setting rate, there are different degrees of differences among Leymus chinensis plants, which may be caused by the instability and complexity of the genetic basis of Leymus chinensis population caused by cross-pollination besides external influences.

In the flowering period of Leymus chinensis, if the weather conditions are suitable, there are many flowers, good pollination and high seed setting rate. If the weather is dry or too humid, there will be fewer flowers, poor pollination and more grains. According to the investigation of Grassland Research Institute of China Academy of Agricultural Sciences (1975) in Wudong Banner, Inner Mongolia, the seed setting rate of Leymus chinensis is very low, only about 30%, ranging from 10% to 60%. The seed setting rate per panicle is also very different, the lowest is about 10%, and even there is no fruit in some years, and the highest is over 60%. Under natural conditions, the seed setting rate of Leymus chinensis is extremely low, which restricts its application in artificial grassland construction. The heading and flowering of Leymus chinensis population are not concentrated, and the duration is as long as 57 days and 62 days respectively. Pollen can not meet cross pollination, which is an important reason for the low seed setting rate of Leymus chinensis population. In addition, filariasis is also a factor affecting the seed setting rate of Leymus chinensis. At the same time, the seed setting rate is also affected by many factors, such as different growth years, individual plant differences, uneven nutrient distribution and so on. Ecological factors such as loose soil, sufficient water and rich mineral nutrition can improve the seed setting rate of Leymus chinensis. In practice, in order to improve its seed setting rate, it is necessary to choose areas with good hydrothermal conditions to plant Leymus chinensis, especially as the seed breeding base of Leymus chinensis, and to consider the hydrothermal conditions and the supply of suitable nutrients.

Under natural conditions, Leymus chinensis mainly reproduces asexually by rhizomes, supplemented by sexual reproduction. Asexual reproduction mainly depends on the growth of rhizomes, which is greatly influenced by the physical properties of the soil at the rhizomes. Generally speaking, the more solid the soil, the less conducive to the growth of roots. In the same soil, the degree of soil hardening mainly depends on the size of soil bulk density and the amount of soil moisture, but for saline soil, it is also affected by soil salt content. Leymus chinensis living in the second year has an average of 4 ~ 10 rhizomes per plant (up to 15 rhizomes), an average length of 0.7m (up to 2m), and an average of 100 internodes per plant, criss-crossing into a net. With the increase of cultivation years, there are more and more rhizomes. So the year when Leymus chinensis was planted was 6500.