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连续3年的试验研究表明,采用合理的定植密度、定干高度和修剪方式,配合科学的田间管理措施,可以使柳树良种采穗圃穗条产量比对照提高40%~50%,穗条质量优良,达到了快速繁殖良种的目的 相似文献
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研究表明:桤木无性系植株嫩枝总芽数主要取决于树龄和无性系遗传特性,同时与无性系植株定干高度、修枝、施肥等密切相关。在桤木无性系采穗圃中,无性系植株定干高度以90 cm为宜,无性系植株枝条宜进行轻短截,并加强施肥管理,既可提高嫩枝总芽数,又能扩大树冠,增强树势,提高采穗圃穗条的产量和质量。 相似文献
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连续3年的试验研究表明,采用合理的定植密度,定干高度和修剪方式,配合科学的田间管理措施,可以使柳树良种采穗圃穗条产量比对照提高40%~50%,穗条质量优良,达到了快速繁殖良种的目的。 相似文献
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通过多种对比试验,结果表明,建立水杉优良无性系采穗圃的有效途径是:选用1年生的亲本实生苗作砧木,1年生优良无性系母株上的枝条作接穗;秋天落叶后,采集接穗须贮藏于冰箱(4~8℃)中;采穗圃设计植株密度为40cm×40cm,选择土壤肥沃,水分条件好的立地作圃地为好。 相似文献
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良种沙棘采穗圃的建立及插穗生产技术研究 总被引:1,自引:0,他引:1
通过对良种沙棘采穗圃的建立及插穗生产技术的试验研究表明 :母本植株的产穗率主要取决于树龄、栽植密度和品种的特性 ,同时与母本植株修剪、施肥灌水以及剪穗方法也密切相关。因此 ,建立良种沙棘采穗圃 ,应选择经济性状优良且生长势强、抽枝、成枝率高的品种 ,栽植密度选择株行距 1m× 2m ,对母本植株进行轻、中短截、老龄枝条更新、施肥灌水等加强管理 ,采取正确的采穗方法 ,既提高产穗率 ,又扩大树冠 ,增强树势 ,保证采穗圃的使用年限及插穗的高产稳产 相似文献
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Jin Weizhu Kong Degang Northeast Forestry University 《林业研究》1991,2(1):108-112
Oblique cutting of wood is an important form of cutting wood.With the developingof woodworking industry,it is widely used in wood machinary processing such as planing,milling,sawing,drilling and so on.This paper takes oblique planing and helix milling of wood as examples.The influences of bevel angle and other factors on the cutting force have been shown.The changingrules of cutting forces have been summarized.On the basis of it,we especially carried out theoreticalanalysis on the changing rules of cutting forces and discussed the influence of the changing rules onpractice. 相似文献
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丽江云杉扦插促根剂配方筛选和插条效应 总被引:2,自引:1,他引:1
以丽江云杉5年生母树为采穗母株,研究了丽江云杉扦插促根剂配方的最佳组合和不同插穗条件对生根的响应,结果表明:扦插后10天愈伤组织开始形成,40天时根尖开始出现,50~70天是生根的高峰期和根系发育期。在进行丽江云杉插穗处理时,应选择300 mg/L IBA处理2 h,生根率可达到90%以上,插穗类型对生根影响不显著,顶轮、一级和二级侧枝做插穗都能获得较高质量的扦插苗,8~12 cm长的插穗是适宜的插穗长度。硬枝和嫩枝扦插生根效应明显,硬枝的扦插成活率高,成活苗根系发达、健壮。 相似文献
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Summary Slow speed wood cutting tests were carried out in which cutting forces were measured as a function of applied tool-work electrical potential. The cutting tool and workpiece were electrically insulated so that there was no current flow. Applied potential had no discernible effect on the cutting forces measured in the cutting of unextracted and extracted wet wood. 相似文献
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Dr. B. E. Klamecki 《Wood Science and Technology》1976,10(3):209-214
The variation of the coefficient of friction with normal load and tool surface finish in slow speed orthogonal cutting of white fir was investigated to determine the relative importance of different sources of friction. Cutting forces were measured as a function of tool-chip contact length and tool surface roughness. The coefficient of friction was independent of tool roughness for roughness in the range of typically well-finished cutting tools but did become a factor for large values of tool surface roughness. The data indicate that for well-finished cutting tools the primary friction mechanism is adhesion between the tool and work and that for rough tool surfaces the effect of tool surface asperities (unevennesses) as they advance through the chip becomes an important source of friction. 相似文献
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本文详细论述了采伐量和采伐方式对森林生态环境的影响,强调选择合理的采伐量和采伐方式对维护生态平衔的重要性,提醒人们强化生态意识,以防大自然对人类的再次惩罚。 相似文献