10种栎属植物高干乔木植株叶片的营养成分测定及营养品质评价

Leaf Nutrient Content Measurement and Nutritive Quality Evaluation of 10 Tall Arbor Trees from Quercus Linn.

栎属(Quercus Linn.)植物叶片的营养品质是选育饲料用柞树新品种的重要考核指标。测定10种栎属植物高干乔木植株叶片中的18种营养成分含量,其中总糖、还原糖质量比分别为33~85 mg/g、32~83 mg/g(变异系数分别为25.9%和25.1%),粗蛋白质量分数为14.8%~19.9%(变异系数8.7%),粗脂肪质量分数为2.3%~3.1%(变异系数9.8%),粗淀粉质量比为52~85 mg/g(变异系数16.1%),粗纤维质量分数为22.3%~26.7%(变异系数5.8%),灰分质量比为38~59 mg/g(变异系数14.2%),水分、全氮的质量分数分别为49.5%~59.4%和2.36%~3.18%,全磷质量比为4.44~17.06 mg/g,全钾、铁的质量比分别为8.29~11.80 mg/g和0.306 0~0.597 8 mg/g。对栎属植物叶片中不同营养成分含量间的相关性分析结果表明:粗蛋白和全氮含量均与全磷含量呈极显著正相关(相关系数分别为0.796和0.841),粗蛋白与粗淀粉的含量呈显著负相关,粗蛋白与粗脂肪和硒的含量均呈显著正相关,粗脂肪与灰分和全氮的含量分别呈极显著负相关和显著正相关,粗淀粉与还原糖、全氮、硒的含量均呈显著负相关,其中相关性最高的是全氮与粗蛋白的含量(相关系数为1.000),其次是总糖与还原糖的含量(相关系数为0.990)。以栎属植物叶片中18种营养成分的含量为变量,采用主成分分析方法提取的前5个主成分对解释变量的累积方差贡献率为89.501%。其中第1主成分主要综合了总糖、还原糖、粗脂肪、粗蛋白、全氮、全磷等的含量信息,包含了原来信息量的30.341%,命名为主要能量因子;第2主成分的方差贡献率为23.073%,也包含粗蛋白和全氮的含量信息。聚类树在组间联结20处,将供试的10种栎属植物分成3类:第Ⅰ类和第Ⅱ类包括槲栎组的8个种类;第Ⅲ类为麻栎组的2个种类。研究结果丰富了栎属植物叶片营养成分的基础数据,并且基于叶片中营养成分含量的聚类可作为栎属组间分类及亲缘关系分析的依据之一。

Leaf nutritive quality of Quercus Linn. trees is the important basis for selection and breeding of new oak varieties for feed use. Contents of 18 nutritional components in leaves of tall arbor trees from 10 Quercus species were measured. The results showed that the mass ratio of total sugar and reducing sugar were 33-85 mg/g and 32-83 mg/g with variation coefficient of 25. 9% and 25. 1%,respectively; the mass fraction of crude protein was 14. 8% to 19. 9% with variation coefficient of 8. 7%; the mass fraction of crude fat was 2. 3% to 3. 1% with variation coefficient of 9. 8%; the mass ratio of crude starch was 52 to 85 mg/g with variation coefficient of 16. 1%; the mass fraction of coarse fiber was 22. 3% to 26. 7% with variation coefficient of5. 8%; the mass ratio of ash was 38 to 59 mg/g with variation coefficient of 14. 2%; the mass fraction of moisture and total nitrogen were 49. 5% to 59. 4% and 2. 36% to 3. 18%,respectively; the mass ratio of total phosphorus was 4. 44 to17. 06 mg/g; and the mass ratio of total kalium and ferrum were 8. 29 to 11. 80 mg/g and 0. 306 0 to 0. 597 8 mg/g,respectively. In correlation analysis,crude protein and total nitrogen contents exhibited extremely significant positive correlation with total phosphorus content,and the correlation coefficient was 0. 796 and 0. 841 respectively; crude protein content displayed significant negative correlation with crude starch content; crude protein content had significant positive correlation with crude fat and selenium contents; crude fat content had extremely significant negative correlation with ash content and positive correlation with total nitrogen content; and crude starch had significant negative correlations with reducing sugar,total nitrogen and selenium contents. Among all the correlations,the correlation coefficient between crude protein and total nitrogen contents was the highest（1. 000）,and that between total sugar and reducing sugar ranked the second（ 0. 990）. The first five principal components had a cumulative contribution rate of 89. 501% to total variability based on principal component analysis using contents of 18 leaf nutritional components in Quercus trees as variants.Among them,the first principal component represented information from total sugar,reducing sugar,crude fat,crude protein,total nitrogen and total phosphorus,which covered 30. 341% of the original information and was designated as main energy factor; the second principal component had a contribution rate of 23. 073%,which also included information of crude protein and total nitrogen. The cladogram had 20 linkages between groups,dividing 10 species of Quercus plants into 3 clades. Clades Ⅰ and Ⅱ include 8 species of Quercus aliena group,and clade Ⅲ includes 2 species of Quercus acutissima group. These results enrich the basic data on leaf nutritional components of Quercus plants. Moreover,clustering analysis based on contents of leaf nutritional components can be used as one of the references for classification and phylogenetic analysis between various groups of Quercus plants.