优质豆科牧草混播技术

文章通过对豆科牧草适宜混播组合、播种量比例分配、播种技术要点及采种的简介,进一步了解豆科牧草混播技术,以提高种草的生态效益和经济效益。     

三种野生豆科牧草引种试验初报

文章观察了来自俄罗斯乌兰乌德的黄花苜蓿、红三叶和来自伊尔库茨克地区的牧地山黧豆三种野生豆科牧草的种子萌发、幼苗生长发育及物候期。对硬实率、发芽率、发芽指数及幼苗的生长速度、干鲜重等进行了观测。结果表明:三种野生豆科牧草均具有较高的硬实特性;在种子萌发过程中黄花苜蓿发芽率和发芽指数均相对较高;三种牧草生育期均较长。     

后山地区几种一年生豆科牧草适应性的研究

研究一年生旱作豆科牧草的生态适应性,选择合适的豆科牧草品种,对于挖掘牧草生产潜力,发展畜牧业,建立合理的轮作体系都有重要意义.本文为1988～1989年在商都县的试验结果,现总结如下.一、试验概况试验在商都县哈报沟村南平缓的旱地上进行,前茬一致,地力均匀,土质沙壤土,肥力较低,有机质含量只有0.617%,全氮含量0.047%.参试牧草品种为蒙苕1号、     

绿地建植中可选豆科牧草品种简介

节约型生态农业就是在生产、流通、消费中采用综合性措施,提高资源的利用率,用最少的资源消耗获得最大的经济和社会收益,减少环境污染,保障经济社会可持续发展.新疆是农牧区,绿地建植采用豆科牧草品种就是要改变传统的高投入、高消耗、低收益的种植方式为种植当地豆科牧草品种的方式.     

龙里县优良牧草复合试验示范初报

在我省龙里县选择5种牧草进行引种栽培及禾本科和豆科的各种配比试验。为该县适应牧草品种的筛选提供了试验依据。     

林草间作的优良草种——紫花苜蓿栽培技术

苜蓿,又名紫花苜蓿、紫苜蓿。原产于中亚细亚高原地带。是世界上栽培最早的牧草,素有豆科"牧草之王"的美称。苜蓿在我国已有2000多年的栽培历史,     

用接种根瘤菌的沙打旺种子进行飞播造林试验

<正> 沙打旺(Astragalus adsurgenspau)又名直立黄芪,适应性强,耐寒、耐干旱瘠薄、耐盐碱、抗风沙。榆林县飞播试验区主要选在土壤贫瘠的盖沙黄土地貌类型上,飞播的沙打旺在苗期有效根瘤不多,共生固氮作用不强,生长发育受到影响。为了促进沙打旺的生长发育,提高单位面积的产草量,我们从1982年起承担了中国农科院土肥所豆科牧草根瘤菌组关于“飞播豆科牧草接种根瘤菌效果大面积示范”的课题。现将沙打旺接种根瘤菌试验结果总结如下:     

韩城市椒园生草模式探讨

通过韩城市花椒园生草实践证明，椒园合理套种美国白三叶等多年生豆科牧草，既可改善园内生态条件、又能提高花椒品质，是一项简单易行、经济实惠的花椒园生态、立体经营模式。     

平欧杂种榛林下套种牧草试验

开展了章古台沙地栽培平欧杂种榛和林下套种牧草试验,对平欧杂种榛和牧草的根系分布进行调查分析。研究表明:平欧杂种榛单株根系垂直分布集中在0～30 cm土层,水平分布在以树干茎部为中心半径75 cm树冠垂直投影范围内;不同牧草根系主要分布在0～20 cm土层,与榛树存在争肥的可能。平欧杂种榛林下套种牧草,在干旱和半干旱地区应选择根冠比小、根系分布浅且与榛树根系重叠率小的豆科牧草白三叶或红三叶作为生草草种。     

生态林业新模式——椒园生草

椒(花椒)园生草就是在花椒行间种植对椒树生产有益的豆科牧草作为覆盖物,每年定期青割后放置原地或取走作树盘覆盖材料的椒园管理方法。     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

泡桐叶片蛋白质多态性及其聚类分析(英文)

根据白花泡桐（Paulownia fargesii）、白花兰考泡桐（P.elongata f. alba）、毛泡 桐（P. tomentosa）、川泡桐（P. fargesii）、山明泡桐（P. lamprophylla）、成都泡桐 (P. albiphloea var chengtuensis)、鄂川泡桐（P. albiphloea）、南方泡桐（P. austra lis）、白花泡桐（P. fortunei）、兰考泡桐（P. elongata）叶片蛋白质单向电泳和双向 电泳结果，可将它们聚类分为白花泡桐组（白花泡桐和白花兰考泡桐）、南方泡桐组（南方 泡桐和成都泡桐）和毛泡桐组（毛泡桐、川泡桐、鄂川泡桐、山明泡桐和兰考泡桐）。该结 果为泡桐属植物的分类提供了参考依据，也为泡桐属植物种确立、杂种鉴定和新品种培育奠 定了基础。     

Ectomycorrhizal inoculation of Douglas-fir transplanted container seedlings with commercially produced inoculum

Commercially produced vegetative inocula of Laccaria laccata and Hebeloma crustuliniforme successfully formed ectomycorrhizae with Douglas-fir transplanted container (plug+1) seedlings. After 4.5 months in containers, 83% and 90%, respectively, of short roots were mycorrhizal. L. laccata- or H. crustuliniforme-inoculated seedlings had significantly more mycorrhizal and total short roots than Pisolithus tinctorius-inoculated (4% mycorrhizal root tips) or uninoculated control seedlings. No significant differences were detected in seedling growth at the end of the container phase.After transplantation and growth in nursery beds for 17 months, mean new short root colonization of all seedlings was 80%. H. crustuliniforme persisted as a dominant mycorrhizal fungus on seedlings initially inoculated with this fungus. L. laccata-inoculated seedlings had 40% of their short roots colonized by L. laccata and another 40% by native fungi Rhizopogon and Thelephora spp. All mycorrhizae of control seedlings and those inoculated with P. tinctorius were formed by fungi native to the nusery beds. A significant fungal treatment effect was detected for shoot height only. Control seedlings were significantly taller than L. laccata-inoculated seedlings after transplanting.This article is part of senior author's thesis in partial fulfillment of the Ph.D. degree in the Department of Forest Science at Oregon State University, Corvallis.     

Rehabilitation of diseased cacao fields in Peru through shade regulation and timing of biocontrol measures

The objective of this case study was to test the effectiveness of biocontrol for the rehabilitation of abandoned, diseased (moniliasis, witches' broom and black pod) cocoa and to develop testable hypotheses regarding the effect of shade and biocontrol timing. Three trial fields differed in their shade regimes. Biocontrol was administered starting either at flowering or pod filling. Disease incidence and yield were compared with cultural control alone. Biocontrol reduced moniliasis from 49% to 25%, independent of the shading regime and application time. Witches' broom was most severe without shade and unaffected by biocontrol. No significant effects on black pod were observed. Although biocontrol increased percentage healthy fruit independent of shading and timing, only the shaded plot with biocontrol from flowering onwards responded with increased yield. Our hypothesis is: 'In the rehabilitation of abandoned cacao, only fields under sustainable shade management and early onset of biocontrol can realise their production potential.' This revised version was published online in June 2006 with corrections to the Cover Date.     

Protein diversity ofPaulownia plant leaves and clusters

Paulownia tomentosa, P. fargesii, P. lamprorhylla, P. albiphloea, P. australis, P. fortunei, P. elongata, P. elongata f. alba andP. albiphloea varchenggtuensis were classified into three groups:P. fortunei group (P. fortunei andP. elongata f. alba);P. australis group (P. australis andP. albiphloea varchenggtuensis) andP. tomentasa group (P. tomentasa, P. fargesii, P. albiprhlaca, P. lamproprhylia andP. elongata) accordance to the results of the single and two-dimensional SDS-PAGE of protein in thePaulownia tree leaves. The result could lay a foundation for classifying the GenusPaulownia plants. Foundation Item: This paper was supported by National Nature Science Foundation of China and Nature Science Foundation of Henan Province. Biography: FAN Guo-qiang (1964-), male, Professor in Institute ofPaulownia Henan Agriculture University. Zhengzhou 450002, P. R. China. Responsible editor: Song Funan     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Litterfall,litter decomposition and the use of mulch of four indigenous tree species in the Atlantic lowlands of Costa Rica

Litterfall, forest-floor litter biomass and nutrients, short-term litter decomposition and the effects of leaf mulches on initial growth of maize were studied for four indigenous tree species with agroforestry potential:Stryphnodendron microstachyum Poepp. et Endl.(S. excelsum), Vochysia ferruginea Mart,Vochysia guatemalensis Donn. Sm. (V. hondurensis) andHyeronima alchorneoides (O), growing in a young experimental plantation in the Atlantic humid lowlands of Costa Rica. Total annual leaf litterfall was higher inV. ferruginea plots, followed byS. microstachyum, V. guatemalensis andH. alchorneoides; all with values comparable to those reported for other tree species grown in agroforestry combinations in humid tropical regions. Forest-floor litter accumulation was highest underV. ferruginea andV. guatemalensis. Both litterfall and forest-floor litter material had similar patterns in nutrient concentrations: N was higher inS. microstachyum, Ca was higher inV. guatemalensis, K was higher inH. alchorneoides; Mg was higher inV. guatemalensis andH. alchorneoides; H. alchorneoides andV. guatemalensis had the highest P.V. ferruginea litter decomposed more slowly, whileS. microstachyum apparently decomposed faster than the other species. The twoVochysia species showed increases in N and P concentration in decomposing litter after seven weeks in the field,H. alchorneoides showed an increase in litter N and a decrease in litter P, andS. microstachyum showed a net decrease in both N and P over the same time period. The patterns found in the litter bag study were confirmed by results obtained in a tethered-leaves experiment.S. microstachyum andV. ferruginea litters lost more weight when mixed in a 11 proportion than either of them alone. Maize seedlings growing in plots mulched withS. microstachyum andH. alchorneoides leaves showed greatest initial growth, confirming patterns found in decomposition and nutrient release studies. The results show that these species could be used in agroforestry combinations with different advantages according to the specific objectives desired, whether these are soil protection, nutrient recycling, or enhancement of the growth of associated crops.     

Biogeochemical impacts of clearfelling and reforestation on blanket-peatland streams: II. major ions and dissolved organic carbon

Streams and drains in blanket-peatland forest in western Ireland were sampled weekly over 5 years, 1996–2000, using continuous, depth-proportional passive sampling. Analysis was for pH, alkalinity by Gran titration, anions by IC, metals by ICP, aluminium speciation by loaded-resin exchange, and dissolved organic carbon (DOC) by absorbance at 320 nm.

Effects of felling are identified graphically from two forest drains whose catchments (both about 1 ha) were clearfelled, and partial clearfelling of one larger catchment (somewhat over 1 km²), in summer 1999. Calcium concentrations and alkalinity were increased in the drain- and streamwater from the felled areas. The pH was increased in drains, while in the larger stream, pH range decreased while the mean increased. Phosphorus increased markedly with clearfell, in the absence of recent fertilising, and also increased with fertilising; these results are reported in an accompanying paper. Ammonium-nitrogen concentrations were increased in the two drains with felling, and temporarily decreased in the larger stream. Nitrate increased in some cases. Potassium and manganese concentrations also increased. Concentrations of DOC and organic monomeric aluminium increased gradually, subject to a continuing strong annual cycle. There were no clearfelling effects on concentrations of solphate, suspended solids or inorganic monomeric aluminium. In the two drains (fully clearfelled), concentrations of sodium, chloride and magnesium, and conductivity, were all reduced after felling. Fertilising effects other than for phosphorus were indistinct.

Effects of the combined clearfell–reforestation treatment were testable statistically, using randomised intervention analysis, between two larger streams (1 km²) as a treatment–control comparison. There were statistically significant positive responses in streamwater concentrations of nitrate, potassium, calcium, DOC and aluminium fractions. The implications for management practice depend on whether the loss of nutrients is sustainable for future crop productivity, and whether critical limits and loads of receiving ecosystems are exceeded.     

Some biological interactions between the parasitoid <Emphasis Type="Italic">Anagyrus pseudococci</Emphasis> (Girault) (Hymenoptera: Encyrtidae) and its host <Emphasis Type="Italic">Planococcus ficus</Emphasis> (Signoret) (Hemiptera: Coccoidea: Pseudococcidae)

The development, longevity, fecundity and life-table parameters of the endoparasitoid Anagyrus pseudococci (Girault) (Hymenoptera: Encyrtidae), 15 d.o. (3rd-instar nymphs) and 21 d.o. (young adult females) of the vine mealybug, Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) at 28 ± 1°C, 65 ± 10%RH and 16:8h L:D under laboratory conditions. The developmental time of female parasitoids within the host was 17.7 ± 0.39 days in 15 d.o. and 16.65 ± 0.25 days in 21 d.o. hosts; for males, development time was 16.85 ± 0.29 and 15.25 ± 0.09 days, respectively. The average number of offspring per female was 22.35 ± 1.68 in 15 d.o. and 34.8 ± 2.56 in 21 d.o. vine mealybugs. The longevity of female parasitoids was 14.8 ± 0.98 days in 15 d.o. and 15.65 ± 0.92 days in 21 d.o. mealybugs, respectively; for males, longevity was determined as 7.3 ± 0.43 and 6.7 ± 0.54 days, respectively. The mean time of pupation was 7.85 ± 0.003 days in 15 d.o. mealybugs and 8.65 ± 0.003 days in 21 d.o. mealybugs. The aggregate encapsulation rate in the parasitized 15 d.o. mealybugs was 49.73 and 60.36% in 21 d.o. mealybugs. Furthermore, effective encapsulation was 24.82% in 15 d.o. mealybugs and 37.50% in 21 d.o. mealybugs. Population growth rate (r _m) for A. pseudococci was 0.0999 female/female/days in 15 d.o. mealybugs and 0.1269 female/female/days in 21 d.o. mealybugs. The mean population generation time was 23.49 days for parasitoids reared in 15-days-old and 22.39 days when reared in 21 d.o. mealybugs.     

Defoliation by the Needle-shortening Pine Gall Midge,Thecodiplosis brachyntera,on Pines in Central Sweden

An outbreak of the needle-shortening pine gall midge, Thecodiplosis brachyntera , occurred on Scots pine, Pinus sylvestris (L.) and lodgepole pine, P. contorta (Dougl.) in central Sweden during 1995-1998. The larval feeding of T. brachyntera kills current-year needles and heavy infestation causes severe defoliation. A pattern of fluctuating defoliation among years and sites was found on both pine species. Defoliation was evenly distributed in the crown of P. sylvestris during years of high as well as low infestation; apical whorls had as much defoliation as basal whorls. In P. contorta , however, there was a tendency for defoliation to be concentrated on branches in the most apical whorls. Growth ring increments on P. sylvestris with high levels of defoliation (71%) did not differ from trees with moderate levels (26%) of defoliation. Shoot lengths were significantly shorter, however, on heavily infested trees the year after defoliation.