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81.
采用7、10、11和16个月生的湿加松无性系扦插苗造林,对造林成活率及5年生时的保存率和生长量调查分析结果显示:湿加松的成活和保存率比湿地松略低,但生长量明显大于湿地松,说明湿加松生长优势明显,有较大的推广价值;4种苗龄的湿加松无性系苗造林效果比较,10、11和16个月苗龄的湿加松苗造林后的成活率、保存率和生长量均显著优于7个月苗龄的湿加松苗。综合考虑育苗成本和造林效果,认为采用10或11个月苗龄的扦插苗造林效果好。 相似文献
82.
4种荧光假单胞菌拮抗菌株对湿地松猝倒病病原菌的抑制效果 总被引:1,自引:1,他引:0
以湿地松猝倒病病原菌为靶标菌,测定4种荧光假单胞菌拮抗菌株对其的抑制效果及各拮抗菌株在湿地松根部的定殖能力。结果表明:Q2-87、2-79、1M1-96对湿地松猝倒病的3个病原菌均表现出一定的抑制效果,而Pf-5几乎无抑制作用。在室内防治试验中,2-79、Q2-87、Pf-5表现出一定的防病效果,但在室外均未表现出防病效果。4种拮抗菌株均可在湿地松根际定殖,但是在根部不同部位的分布并没有规律可循。在定殖过程中,各拮抗菌株在湿地松根部的菌量密度随着时间的延长而增加,在某一时刻达到峰值后数量逐渐减少。 相似文献
83.
调查了福建省德化葛坑国有林场4种不同施肥处理后,2、3、4年生湿加松树高、胸(地)径和病害指数变化情况。结果表明,(1)不同施肥处理对湿加松早期树高、胸(地)径和松感病指数均产生显著影响,各生长年度树高、胸(地)径生长大小依次为:施氮磷钾复合肥与硼砂〉施氮磷肥与硼砂〉施氮磷肥〉对照(不施肥),而感病指数大小则为:对照(不施肥)〉施氮磷肥〉施氮磷肥与硼砂〉施氮磷钾复合肥与硼砂;(2)湿加松感病指数与树高、胸(地)径均呈显著的负相关。由此表明适当的施肥管理可以促进湿加松早期树高、胸(地)径的生长和提高其抗病害能力。 相似文献
84.
K.C.S. Rodrigues P.C.N. Azevedo L.E. Sobreiro P. Pelissari A.G. Fett-Neto 《Industrial Crops and Products》2008,27(3):322-327
The production of oleoresin from Pinus trees is a relevant economic activity in developing countries, since it provides terpenes used in the chemical industry. The oleoresin production by trees of Pinus elliottii in southern Brazil was investigated. Trees of approximately 28 years of age were individually analyzed for oleoresin yield using the bark streak method of wounding for resin tapping. Plain wounding and wounding followed by application of commercial resin stimulant paste, composed of an ethylene precursor (CEPA) and sulphuric acid, were used as reference treatments. The optimum concentrations of CEPA and sulphuric acid in the stimulant paste were investigated in relation to oleoresin yield, as well as the shape of wound and tree diameter. The replacement of CEPA with auxin in the resin stimulant paste was also evaluated. The results showed that both horizontal and V-shaped streaks are equivalent for oleoresin yield. Trees with larger diameter at breast height, defined as the trunk diameter 1.4 m above the ground (22–23.5 cm) yielded more oleoresin than their smaller counterparts (18–19.5 cm). Oleoresin yield was equivalent with stimulant pastes containing between 1.5 and 4.5% CEPA. Trees exposed to stimulant pastes containing from 3 to 4.5% CEPA had average year oleoresin yield above 5 kg. The use of 20% sulphuric acid in the stimulant paste resulted in higher oleoresin yields. Auxin (2,4-D at 1 mM) was effective in replacing CEPA in the stimulant paste, particularly in smaller DBH trees or after 1 year of application in larger DBH individuals. In conclusion, cost reductions on resin tapping can be achieved by adjusting stimulant paste components and managing subsets of trees in specific fashion based on DBH ranges. 相似文献
86.
不同造林技术措施对湿地松幼林生长影响的研究 总被引:4,自引:0,他引:4
在湖南攸县设置了反映湿地松人工林造林各主要技术环节的试验林体系,以研究不同造林技术措施对湿地松幼林生长的影响。经对试验林固定样地进行连续7年定期、定位观测及统计分析表明:在湿地松人工造林的各项主要技术措施中,立地选择、良种选择和造林密度是影响幼林生长的最重要因素,幼林抚育对湿地松幼林生长有较明显影响,而整地方式与规格对幼林生长无明显影响。 相似文献
87.
以森林经营模式理论为指导,建立了湿地松短周期纸浆材原料林经营模式的经营模拟系统,并以简明的森林经营数表体现出来,为湿地松纸浆材原料林的经营提供科学依据. 相似文献
88.
Although gravitropism of maize (Zea mays L.) roots is dependent on light, it is not known if light affects the gravitropism of pine radicles. Therefore, seeds of
slash pine (Pinus elliottii Englm.) and loblolly pine (Pinus taeda L.) were germinated under constant light or constant darkness. A gravitropic set-point angle (GSA) of 90° indicates the radicle
is pointed horizontally while a GSA of 0° indicates the radicle is growing toward the center of the earth. After 20 days from
sowing, the GSA was less than 10° in both light and darkness. Therefore, gravitropism of both pine species occurred in the
dark. The presence of light initially stimulated gravitropism but this effect was ephemeral. After 25 days from sowing, there
was no significant difference in radicle growth among light treatments, suggesting that darkness did not affect pine radicle
gravitropism. However, light did increase germination of both species. Radicle length was slightly increased when seeds germinated
in the dark. 相似文献
89.
90.
论火炬松无性系林业发展前景 总被引:1,自引:0,他引:1
讨论了无性系林业发展前景,着重分析了火炬松无性系造林增产效益,及火炬松、湿地松适地适树的增产潜力,为我省国外松造林提供科学依据。 相似文献