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81.
KU Daping Bernie DELL. Research Institute of Tropical Forestry CAF Guangzhou China . Murdoch University. Perth. Australia 《中国林业科技(英文版)》2002,(1)
Eucalypts are very popular for revegetation in many parts of south China because of their capacity to tolerate degraded sites and unfertile soils,and their fast growth potential to coppice. This paper reviews a decade of field trials in china, undertaken as part of several bilateral researchprograms in plantation forestry, concerning the use of fertilizers, harvest residue management and inoculation with ectomycorrhizal fungi. One of the key questions addressed is whether the productivity of plantation eucalypts in south China can be increased to the world average by nutrient management across a rotation. 相似文献
82.
四川主要农用土壤中丛枝菌根真菌数量和种类的初步研究 总被引:1,自引:0,他引:1
用形态学分类法测土壤样品中丛枝菌根真菌的数量和种类分布特点,结果表明,丛枝菌根真菌广泛分布于四川农业土壤中,但其数量和种类较少,种群结构单一。共计分离鉴定出3个属18种丛枝菌根真菌,球囊霉属(Glomus)13种,无梗囊霉属(Acaulospora)2种,盾巨孢囊霉属(Scutellospora)3种,其中只有Gl.mosseae,Gl.cale-donium,Gl.constrictum的出现频率大于10%,是主要四川省农用土壤中的优势种。研究还发现,地域因素、土壤类型和土壤的理化性质以及人为因素对丛枝菌根真菌的数量和种类有显著影响(P<0.05)。 相似文献
83.
根据苗木根系分泌物能促进菌根真菌萌发和生长的原理,结合我国林业育苗的特点,提出了松树幼苗截根与人工接种菌根真菌结合的育苗方式。结果表明,截根菌根化育苗在促进根系发育和菌根形成,加速苗木生长,提高苗木生物量、苗木质量和产苗量等方面都有显著优势,苗木的侧根数、侧根总长、苗木菌根化率、吸收根菌根化率、苗高、地径、鲜重、干重分别提高20.0%~960.0%、56.2%~389.5%、0.0%~400.0%、56.2%~1792.0%、22.3%~179.3%、31.2%~253.8%、33.3%~918.2%和21.8%~740.0%,苗木成活率和Ⅰ级苗分别提高9.0%~22.1%和49.3%~150.0%,Ⅱ、Ⅲ级苗和等外苗分别降低40.6%~77.3%、61.6%~88.5%和82.5%~100.0%。利用截根菌根化苗木造林,提高成活保存率5.5%~46.0%,并促进幼树生长,树高、地径和材积指数分别增加13.0%~56.4%、25.5%~61.7%和87.8%~450.0%。效益分析证明,截根菌根化育苗具有明显的经济效益和社会效益,仅苗期可定量计算的增收(节支)总额可达44662元/hm2。 相似文献
84.
Functional compatibility between thirteen tropical fruit trees (Afzelia africana Smith., Adansonia digitata L., Aphania senegalensis Radlk., Anacardium occidentale L., Cordyla pinnata (Lepr. ex A. Rich.) Milne-Redhead, Dialium guineensis Wild., Landolphia heudelottii A.DC., Sclerocarya birrea (A.Roch.) Hochst., Saba senegalensis (A. DC.) Pichon and four reference hosts Balanites aegyptiaca (L.) Del., Parkia biglobosa (Jacq.), Tamarindus indica L. and Zizyphus mauritiana Lam.) and two arbuscular mycorrhizal fungi (AMF) (Glomus aggregatum Schenck and Smith emend. Schenck and Glomus intraradices Schenck and Smith), was investigated. Marked differences were found between them in terms of mycorrhizal formation, root colonization, relative mycorrhizal dependency (RMD) and phosphorus concentrations in shoot tissues. A. africana, L. heudelottii and S. senegalensis did not form symbiotic associations, and the growth of A. africana decreased following mycorrhizal inoculation, while L. heudelottii and S. senegalensis showed no dependency. In contrast, A. digitata, A. senegalensis, A. occidentale, B. aegyptiaca and S. birrea were well colonized with AMF, but did not significantly increase in biomass production. Five fruit trees did, however, show dependency by a positive interaction with G. aggregatum, the most effective AMF. Z. mauritiana was found to be very highly dependent (RMD > 75%), T. indica was highly dependent (50–75% RMD), and D. guineensis, P. biglobosa and C. pinnata were moderately dependent (25–50% RMD). Phosphorus absorption probably contributed to this dependency more than the absorption of potassium. These results indicate that some tropical fruit trees do derive benefits from AM inoculation, while others do not.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
85.
86.
杜鹃花属植物内生真菌对毛棉杜鹃幼苗生长的影响 总被引:1,自引:0,他引:1
对来自粤北3种野生杜鹃花属植物根样中的聚多曲霉(Aspergillus sydowii)(菌株号:YJ1,YS2)、杂色曲霉A. versicolor(菌株号:GD1)3个内生真菌菌株及其混合菌剂进行瓶内接种试验,比较其对毛棉杜鹃(Rhododendron moulmainense)幼苗的菌根侵染率、苗高和生物量的影响。结果表明,3个菌株及其混合菌剂均可与毛棉杜鹃幼苗根系形成菌根共生体,但不同菌剂在不同培养基上对毛棉杜鹃幼苗根系的侵染力、苗高增长和生物量增重效果存在显著差异(P<0.05)。多数菌剂(YS2、M3、M1、M2)在MMN培养基上对幼苗根系侵染力显著高于WPM培养基和混合基质培养基(P<0.05),而多数接菌苗(YJ1、GD1、M2、M3)在WPM培养基上生长显著优于MMN培养基(P<0.05),YS2、GD1和混合菌剂M2(YS2+GD1)对毛棉杜鹃幼苗的增高和增重具有明显的促生作用。 相似文献
87.
Christian?P.?Andersen Ivan?Nikolov Petia?Nikolova Rainer?Matyssek Karl-Heinz?H?berleEmail author 《European Journal of Forest Research》2005,124(3):155-163
Seasonal fluxes of CO2 from soil and the contribution of autotrophic (root + mycorrhizal) to total soil respiration (SR) were estimated for a mixed
stand of European beech (Fagus sylvatica) and Norway spruce (Picea abies) in Central Europe. Mature trees of each species were girdled in August 2002 to eliminate carbohydrate allocation to roots.
SR was measured at distances of 0.5, 1.0, and 1.5/2.0 m from the bole of each tree at 1–2 weeks intervals throughout the fall
of 2002 and monthly during the spring and summer of 2003. The contribution of roots and mycorrhizae to total SR was estimated
by the decrease in SR compared to ungirdled control trees to account for seasonal patterns evident in controls. SR decreased
with soil temperature in the fall 2002 and increased again in 2003 as soil warmed. During most of the study period, SR was
strongly related to soil temperature. During the dry summer of 2003, however, SR appeared to be uncoupled from temperature
and was strongly related to soil water content (SWC). Mean rates of SR in beech and spruce control plots as well as root densities
did not show a clear pattern with distance from the bole. SR decreased to levels below controls in beech within a few days
after girdling, whereas spruce did not show a significant decrease until October 2002, 6 weeks after girdling. In both beech
and spruce, decreased SR in response to girdling was greatest closest to the bole, possibly reflecting increased mycorrhizal
activity close to the bole. Autotrophic respiration was estimated in beech to be as much as 50% of the total SR in the stand.
The contribution of autotrophic respiration was less certain for spruce, although close to the bole, the autotrophic fraction
may contribute to total SR as much as in beech. The large fraction of autotrophic respiration in total SR requires better
understanding of tree level stresses that affect carbon allocation below ground. 相似文献
88.
89.
90.
【目的】探究接种丛枝菌根(Arbuscular mycorrhizal,AM)真菌对不同程度盐分和重金属胁迫下小果白刺Nitraria sibirica Pall.生长的影响,为重金属污染盐渍化土壤的植物-微生物联合修复提供科学依据和数据支持。【方法】采用温室盆栽的方法,模拟不同程度重金属Cd污染(干土中含0、2、5 mg·kg-1 Cd)NaCl型(干土中含0、1.5 g·kg-1 Na+)盐渍化土壤(Cd0Na0、Cd0Na1.5、Cd2Na0、Cd2Na1.5、Cd5Na0、Ca5Na1.5),研究接种AM真菌Funneliformis mosseae对Cd和NaCl胁迫下小果白刺的菌根侵染、元素吸收、离子平衡、生物量、Na+和Cd含量与吸收的影响。【结果】在重金属Cd和NaCl胁迫下,接种F. mosseae的植物根系平均菌根侵染率为12.68%~21.90%。与不接种CK相比,接种AM真菌使不同处理小果白刺总干质量增加101.35%~215.29%;地上部矿质营养元素增加47.55%~21... 相似文献