楸樹不同無性系根段扦插初步研究

馬林江 蔡開元 陳華超 黃國偉 張新葉

摘要：以楸樹不同無性系根段為材料，沙藏過冬后截段消毒進行扦插，研究楸樹根段扦插出苗情況，比較不同無性系根段扦插苗生長差異。結果發現：楸樹根段扦插整體出苗率高，不同無性系出苗率在77%～95%，扦插30 d后根段凸起大量白點，根段兩頭均有大量透明愈傷，45 d后開始出現萌芽，60 d后皮層及根下部愈傷產生大量根系。不同無性系盆栽扦插苗一年生苗高在61 ～81 cm之間，地徑在929 ～1212 mm之間，不同系號間差異達到顯著水平（P<005）。總體來說，根段扦插出苗率高，簡單易操作，推廣應用前景廣闊。不同系號間出苗率及生長存在顯著差異，具有極大的選育潛力。

關鍵詞：楸樹；根段；扦插；生長性狀

中圖分類號：S79225文獻標識碼：A文章編號：1004-3020（2017）04-0086-03

Study on the Root Cuttings of Different Clone of Catalpa bungei

Ma Linjiang（1）Cai Kaiyuan（2）Chen Huachao（1）Huang Guowei（1） Zhang Xinye（1）

（1.Hubei Academy of ForestryWuhan430075；2.Shishou Forest Seed FarmJingzhou434400）

Abstract： The root segments were used as the experimental materials， buried in the sand over the winter， and then cut after intercept and disinfection. Aiming to research the emergence situation of the root cuttings and compare their differences of the growth in different families. The result showed that there were a high germination rate with root cuttings， it was from 77% to 95% . It was germinated significantly after 30 days and appeared a large number of raised white spots on the root，there were a lot of callus at both ends of the root segment. The buds began to appear after 45 days， large root was appeared in the cortex and callus after 60 days. The annual height was from 61 cm to 81 cm and the annual ground diameter was from 9.29 mm to 12.12 mm in different families，there were both significant differences in these families. In general， there were a high emergence rate with root cuttings， it was easy to operate and had a broad application prospects. The emergence rate and growth had significant differences in different families， it had a great value in breeding.

Key words：Catalpa bungei；root segment；cutting；growth traits

楸樹（Catalpa bungei）是紫葳科（Bignoniaceae）梓屬植物，作為特有的珍貴優質用材樹種和著名的園林觀賞樹種，栽培歷史悠久[1]。楸樹材質優良，用途廣泛，樹體高大，樹姿優美，素有“木王”之稱，在中國分布范圍較廣，東起海濱，西到甘肅，北起長城，南到云南[2]。目前國內市場楸木奇缺，市場價格昂貴，中小徑材2 000元/m3以上，大徑材超過4 000元/m3，是一般樹種木材價格的幾倍以上[3]。

楸樹在許多地方開花不結實或者結實不可育，因此實際生產中主要以嫁接、組培等無性方式進行繁殖。陳元祥對楸樹嫁接的砧木選擇、嫁接時間和方法等進行了技術總結，為楸樹繁殖提供了技術支持[4]。韓創舉等建立了較好的楸樹組培體系[5]，梁明武等對楸樹的嫩枝扦插進行了探索[6]，楸樹根段扦插研究相對較少[7]，湖北省之前還沒有開展過相關試驗和研究，因此開展與此相關的探索，生產實際意義重大。根段扦插操作簡單，成本低廉，不僅能豐富楸樹繁育方式，而且針對不同栽培區域的特點，可以根據需要選擇更為合適的繁殖育苗方法。……