引种刺槐无性系形态及叶片营养的初步研究

为了便于研究推广引种刺槐，通过生长季节观察统计3年生林分的形态特征和采样分析叶片营养含量，并结合根插生根能力和田间生长的株高、地径调查数据，对国外引种刺槐初步筛选出的11个无性系（2个来源于匈牙利，9个来源于韩国）及国内2个无性系的形态特征、根插生根能力、生长性状和叶片营养含量进行了比较研究。结果表明:无性系间存在明显的形态和生长差异，但叶片粗蛋白和粗纤维含量均差异不显著（P005）；无性系B和G的株高和地径生长最快，而无性系H1最慢；无性系H2具有最大的叶面积，为其他无性系的3倍；而无性系K4由于叶厚最大，其百叶干质量也最大；这13个无性系根据小叶枚数大致可分为1~3枚、13~17枚、15~23枚和21~25枚4类；无性系间的托叶刺大小区别明显，具有最大的叶面积的无性系H2托叶刺最小；所有无性系均能生根，无性系2N、K5和B的不定根数多，而无性系K3、K4和H1的不定根数少；各无性系之间的叶片粗蛋白含量与叶长×叶宽显著正相关（P0.05），与小叶枚数、复叶柄长和刺长均显著负相关（P0.01）；株高和地径呈显著正相关关系（P0.01），且均与刺基宽显著负相关（P0.05）。 

Morphology and leaf nutrition of introduced Robinia pseudoacacia clones

Morphological characteristics, rooting ability, growth and leaf nutrition at age 3 years were studied on 13 clones of Robinia pseudoacacia, of which 2 were from China (2N and 3-I), 2 from Hungary (H1 and H2) and 9 from Korea. There were significant differences in growth and morphological characteristics among clones, but not in the contents of crude protein and crude fiber in the leaves (P>0.05). Clones B and G recorded the fastest height growth and basal diameter, while clone H1 was the slowest. Clone H2 had the largest leaflets, three times as large as other clones, but K4 had the heaviest dry weight per 100 leaflets because it had the thickest leaves. The 13 clones can be divided into four classes (1-3,13-17, 15-23, 21-25) by the number of leaflets per compound leaf. There were significant differences in the thorn size; H2, with the largest leaflets, had the smallest thorns. All clones produced roots; clones 2N, K5 and B had more number of adventitious roots, while clones K3, K4 and H1 had less. Correlation between content of crude protein and length × width of leaf was positive (P<0.05), while correlation of content of crude protein with number of leaflets per compound leaf, rachis length of compound leaf and thorn length were negative (P<0.01). Plant height and basal diameter were positively correlated with each other (P<0.01) and negatively correlated with base width of thorn (P<0.05).