【作者】 张国君；

【导师】 李云；

【作者基本信息】 北京林业大学 ， 林木遗传育种， 2010， 博士

【摘要】 刺槐虽然是被公认为适合用作饲料的树种,但目前针对用作饲料林的刺槐优良无性系培育和栽培加工利用研究远不能满足饲料业发展的需要。因此,选育高产及高蛋白含量和低单宁含量的饲料型刺槐优良无性系对于刺槐饲料的开发及发展我国木本饲料事业具有重要的现实意义。在此背景下,本研究开展了饲料型刺槐优良无性系的选育和栽培利用研究。对国内外引种初选的11个刺槐无性系的形态、生根、生长和叶片营养进行了研究,除无性系K1和A与普通刺槐2N无明显表型差异外,其余各无性系间差异明显；无性系K5和B的生根能力高于2N,而K4最差；无性系B、G和K2的株高和地径显著优于其他无性系；各无性系的叶片粗蛋白含量由175.9 g kg-1至212.7 g kg-1不等,但无显著差异。综合考虑生长和营养性状,选出了饲料型优良无性系B、G和K2。为了进一步比较不同刺槐无性系间的营养差异,分析了国内外19个刺槐优良无性系的粗蛋白质等常规营养成分和18种氨基酸及单宁含量,利用必需氨基酸分、必需氨基酸指数及模糊最优局势决策法对其营养价值进行综合评价；并以无性系K4为试材进行了反刍动物瘤胃降解试验和单胃动物饲喂试验。结果表明：刺槐各无性系的氨基酸含量为159.8 gkg’-240.0gkg-1,且组成平衡,必需氨基酸分为84.1-118.8,明显高于苜蓿草粉(64.3)和大豆饼(81.3),其综合营养价值除无性系2N、H1、K3和K4与苜蓿草粉相似外,其他无形系均高于苜蓿草粉；且无性系G的单宁含量(6.9g kg-1)显著低于2N(28.9 g kg-1)；无性系K4的茎秆粗蛋白瘤胃降解率高于叶片和整株,而叶片中的酸性洗涤纤维降解率高于茎秆和整株,且嫩枝叶的消化率较高；添加刺槐叶粉20 g kg-1-60 g kg-1时对蛋鸡的生产性能和蛋品质均无负面影响,但添加40 g kg-1时的产蛋量和蛋重明显增加,且添加少量的刺槐叶粉有提高蛋鸡营养物质消化率的趋势。以初选的8个刺槐优良无性系为试材,在北京延庆、北京海淀八家、河南洛宁3个试验点进行了区域化试验,并对2年生试验林的生长和叶片营养进行了分析。结果表明,控制生长及叶片营养的不同基因型与环境存在显著的互作效应,但叶片营养的互作效应可能是由叶片成熟度不同造成的。综合生长和营养的生长适应性和遗传稳定性考虑,无性系83002和K2均适合在3个试验点用于饲料林栽培。结合栽培与经营措施对叶片生物量和营养含量的影响,在北京平原地区刺槐饲料林最佳栽培与经营措施为：栽培密度为0.4 m×0.8 m,定植当年不刈割,第二年开始每年刈割2次(春天不平茬),刈割时期为6月初和8月底,留茬高度20cm-30cm。刺槐无性系K4单一半干青贮效果一般,而与玉米秸秆的混合青贮(33%-50%)效果良好；刺槐无性系K2、柠条青贮饲料发酵品质和营养价值均显著好于紫穗槐,在混合青贮中刺槐和柠条青贮混合品质最佳,与紫穗槐混合的两种混合饲料品质较差；应用刺槐无性系K4饲喂布尔山羊,适口性好,与苜蓿干草的饲喂效果相近。更多还原

【Abstract】 Robinia pseudoacacia are considered to be a promising forage tree, but it is known to contain tannin, which is an anti-nutritional factor. Therefore, development of low-tannin cultivars with desirable feeding responses would be a choice to increase prospect of R. pseudoacacia as a forage crop. The objectives of the present study were to evalue and select the R. pseudoacacia superior clones for fodder.There were distinguishing morphological characters between 9 clones and common R. pseudoacacia 2N, except for Kl and A. Moreover, rooting ability of K5 and B, height and basal diameter of clones B, G and K2 were both significant higher than 2N, while the worst rooting ability was found in K4. No difference was found in crude protein content of leaves (175.9 g kg-1-212.7 g kg-1) among these clones.Contents of crude protein and other routine ingredients and 18 kinds of amino acids in leaves of 19 R. pseudoacacia superior clones were both highly (159.8 g kg-1-240.0 g kg-1) and balanceable. Their nutrional values evaluated by means of amino acid scores (84.1-118.8), essential amino acid index and general method were better or similar to alfalfa (amino acid scores=64.3), and lower tannin content in leaves of G (6.9 g kg-1) than 2N (28.9 g kg-1) was found. Effective degradability of crude protein was significantly higher for stem than for leaf and whole plant, whereas effective degradability of acid detergent fiber was higher for leaf. Ruminal disappearances of nutrients were higher in June than in later stages. No significant effects were seen on either hens’performance or egg quality parameters except for egg mass and egg weight, and quadratic effect on apparent nutrient and amino acid digestibility. Egg mass and egg weight were both high in the diet containing 40 g kg-1 R. pseudoacacia.Interation of genotype-environment of R. pseudoacacia clones was significant in growth, while it may be resulted in leaf nutrition from different leaf maturation in the same season at different sites. Considering leaf biomass and nutrition, a suitable cultivation model should be cutting from second year after planting in spacing of 0.4 m×0.8 m and harvesting two times per year (harvesting in early June and late August while no cutting in spring), cutting height was 20 cm-30 cm.Silage quality of wilted R. pseudoacacia (K4) preserved alone is acceptable. The treatments of K4 mixed with corn stalk (33%-50%) achieved the best silage quality. R. pseudoacacia (K2) and Caragana were significantly better than Amorpha fruticosa in fermentation quality. The mixed silage of R. pseudoacacia and Caragana was the best. In addition, no significant differences were observed between R. pseudoacacia and alfalfa in term of average daily gain as feed for goat.更多还原