不同播种深度对羊草出苗率和幼苗生长的影响

Effects of Sowing Depth on Seed Germination and Seedling Growth of Leymus chinensis

利用盆栽研究了7种播种深度(0cm、1cm、2cm、3cm、4cm、5cm和6cm)对羊草出苗率和幼苗生长的影响。结果表明,羊草出苗率与种子萌发率呈极显著正相关(r=0.9147),而与播深呈极显著负相关(r=-0.9408)。在浅播(0～2cm)条件下,羊草初始出苗时间为5.0～7.7d,最终出苗率为70.0%～80.7%;在深播(4～5cm)条件下,初始出苗时间延迟到16.3～20.0d,羊草种子萌发率下降到41.0%～43.0%,但出苗率不足7%,株高不超过2cm;当播深在6cm以上时,其萌发率为37.0%,但出苗率为0。此外,播种深度显著影响羊草幼苗株高、茎叶鲜重及叶片数量。

A pot experiment was designed to study the effects of seven sowing depths of 0cm, 1cm, 2cm, 3cm, 4cm, 5cm and 6cm on seed germination and seedling growth of Leymus chinensis. Results showed that emergence percentage showed extremely significant positive correlationship with the germination percentage （r= 0. 9147） while extremely significant negative correlationship（r= -0. 9408）with the sowing depth. Under the sowing depth of 0-2cm, the initial emergence time was 5.0-7.7d and the final emergence percentages were 70.0%-80. 7%. When the depths were 4-5cm, the initial emergence time were delayed to 16. 3-20.0d, the germination percentage decreased to 41.0%-43.0%, the emergence percentage was lower than 7% and the seedling height was no more than 2cm. When the sowing depth was deeper than 6cm, the germination percentage was 37.0% but no seedling emerged. In addition, the sowing depths also significantly affected the seedling height, fresh weight of the stem-leaf and the number of the leaves. In conclusion, sowing depth was one of the most important factors affecting the seed germination, emergence and seedling growth of L. chinensis. The optimal burial depths was 1-2cm and it should not exceed than 3cm. Improving the seed germination, sowing at shallow depth, and supplying sufficient water during the seedling period were effective strategies for improving seedling emergence and saving seeds of L. chinensis.