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101.
论述了适宜雷竹栽培的大棚设计与建立、竹笋生长发育与大棚环境条件的关系、单层薄膜大棚酿热增温栽培方法和有关问题的探讨等,并将初步试验结果与竹农生产经验予以总结,有关棚内落叶、提高地温和留笋养竹等存在的问题进行了分析研究,找出了失误的原因和解决方法。  相似文献   
102.
对茶梢蛾幼虫的空间分布型及抽样技术的研究结果表明,幼虫为普通聚集分布,其基本成分是面积为一株油茶大小的个体群,个体间相互吸引。调查时以棋盘式取样为佳。根据空间分布型分析,计算出序贯抽样模型为:最适理论抽样数模型为:  相似文献   
103.
毛白杨,河北杨多代循环繁殖方法的研究   总被引:3,自引:1,他引:3  
张康健  孙长忠 《林业科学》1990,26(2):110-116
从1983年起,对毛白杨、河北杨的扦插繁殖育苗及其机理进行了研究,研究出“多代循环繁殖新方法”,无需任何处理,也无需地膜覆盖,使大田育苗成活率稳定在80%左右;同时研究出快速、简便、繁殖系数高的优树根萌条培育新技术,为毛白杨、河北杨优树的无性系测定、无性系育种和无性系造林创造了条件。  相似文献   
104.
Bareroot jack pine (Pinus banksiana Lamb.) and white spruce (Picea glauca (Moench) Voss) were planted near Elliot Lake, Ontario, on a boreal reforestation site. Site preparation treatments were mixed, mineral and undisturbed (i.e., control) soil. Seedling water relations and growth were examined during the first field season. During the first 28 days after planting, jack pine base (i.e., predawn) and minimum xylem water potential readings were more negative in the control site preparation treatment. White spruce, during the first 10 days, in all site preparation treatments had base and minimum xylem water potential readings more negative than –1.7 MPa. By day 28 base xylem water potentials of white spruce had increased to approximately –1.0 MPa in all site preparation treatments. As the growing season progressed, white spruce minimum xylem water potential readings ceased exceeding the measured turgor loss point first in the mixed followed by the mineral and then control site preparation treatment. Jack pine minimum xylem water potential readings, in all site preparation treatments, almost never exceeded the measured turgor loss point. Water stress and stomatal optimization integrals, day 28 and 125, for both species showed least water stress and greater stomatal optimization in the mixed, mineral and control site preparation treatments, respectively. Both species had less new root growth in the field during the first 28 days after planting compared to seedlings grown for 28 days in a greenhouse for root growth capacity testing. Root growth at 28 days and both shoot and root development at the end of the growing season, were greatest to least in mixed, mineral, and control site preparation treatments, respectively.  相似文献   
105.
高节竹是优良的笋材兼用竹种, 竹鞭延伸生长能力强, 具有较高的鞭笋生产潜力。为评价高节竹鞭笋品质和适口性, 以毛竹鞭笋为对照, 比较两者外观形态和营养物质、呈味物质含量的差异。结果表明:与毛竹鞭笋相比, 高节竹鞭笋略长, 个体质量、基径和蛋白质、纤维素、木质素、单宁、草酸、总酸含量明显较低, 而可食率、糖酸比和脂肪、可溶性糖含量明显较高。高节竹、毛竹鞭笋除鲜味氨基酸含量差异不明显外, 高节竹鞭笋的氨基酸总量及其它氨基酸组分的含量显著低于毛竹鞭笋, 但鲜味氨基酸、甜味氨基酸和芳香类氨基酸组分比例显著高于毛竹鞭笋, 苦味氨基酸组分比例明显低于毛竹鞭笋。研究表明, 高节竹鞭笋较为粗大、可食率高、粗糙度低、适口性好, 质量总体优于毛竹鞭笋。  相似文献   
106.
试验通过采用5因素4水平正交试验法,选出了适合北美兰云杉嫩枝扦插的最佳处理组合:草炭 珍珠岩基质 100 mg/L自配生根剂 2 a母树穗条。通过方差分析发现穗条母树年龄、基质种类对扦插生根率有显著影响,其中穗条母树年龄为2 a时,平均生根率达到了77.5%。基质种类对生根的影响是通过基质质地、通透性、保水力、地温、肥力等多因素共同作用的。综合看,草炭 珍珠岩基质是北美兰云杉扦插最为理想的基质,河沙基质最差。  相似文献   
107.
红锥扦插育苗试验   总被引:8,自引:2,他引:8  
两种扦插基质、不同浓度的4种生根促进剂处理插穗的红锥扦插育苗试验结果表明:不同扦插基质对红锥插条的生根率影响较大,在两种基质中宜以黄心土作为红锥扦插育苗的基质。用生根促进剂处理插条能促进其快速生根,不同的药物和浓度处理插条对红锥插条的生根率和生根速度有显著的影响,其最佳组合J2N4的生根率达90%。  相似文献   
108.
Sasse  Jo  Sands  Roger 《New Forests》1997,14(2):85-105
Stem cuttings of Eucalyptus globulus are used within tree improvement programs and for mass deployment. To be successful, cuttings must perform as well or better than seedlings. The root systems of cuttings are fundamentally different from those of seedlings. If these differences influence growth, the differences and their consequences must be identified and the propagation system manipulated to improve performance of the propagules.Cuttings are only a viable alternative to seedlings as planting stock if the method of propagation does not affect their growth and development adversely. Full-sibling cuttings and seedlings of Eucalyptus globulus were compared under controlled environmental conditions to minimise extraneous sources of variation, and to establish whether changes in growth or development were induced by propagation. On three occasions over a period of eight weeks root-collar diameter, shoot height, leaf and stem weight, shoot/root ratios and root system morphology were measured on cuttings and seedlings. Seedlings were taller than cuttings throughout the experiment, but both plant types had similar height growth rates. Diameter growth rates were lower in cuttings than seedlings, and there were differences in both height and diameter growth rates between families. Root system configuration differed between the plant types. Seedlings had strongly gravitropic tap-roots, with two types of primary roots from which secondary roots emerged. Cuttings had no tap roots, and the main structural components of their root systems were adventitious roots formed during propagation. Cuttings did not develop further structural roots during the experiment, whereas seedlings continued to develop primary roots. Individual primary roots of cuttings were longer and had larger mid-point diameters than those of seedlings, but the total length of primary roots was greater in seedlings. Seedlings also had a greater number and total length of secondary roots. Shoot/root ratios, calculated from a range of functional measures, were higher in cuttings than seedlings.  相似文献   
109.
竹笋象危害对竹材物理力学性质的影响   总被引:4,自引:0,他引:4  
对受笋万纹象(Otidognathus rubriceps Chevrolot)、一字竹笋象(O.davidis Fairmaire)、大竹笋象(Cyrtatrachelus longimanus Fabricius)危害后断梢毛竹、竹腔注药防治后毛竹、正常毛竹3种竹材进行竹材抗弯强度、抗弯弹性模量和顺纹抗拉强度测定结果表明,与正常毛竹相比较,受竹笋象危害断梢毛竹差异显著,3个竹材物理力学性质指标分别下降了43.79%、39.01%、29.28%,竹腔注药防治后毛竹3个指标下降了13.87%、10.95%、9.01%,但差异不显著,不影响竹材的使用价值.  相似文献   
110.
城市化的过程离不开工业经济的发展,在新兴的城市以及在城市新兴的工业园区内,工业用地都占有极大的比重。因此,工厂企业的绿地景观与公共空间、商业空间以及其它城市空间的绿地景观一样是城市绿地景观的重要组成部分,必须引起我们的重视。作者从绿地景观设计的角度出发,结合珠海科斯特电源有限公司绿地景观设计的实例,探讨了工厂企业在绿地景观设计方面的若干问题。  相似文献   
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