Tropical Moist Forest Silviculture and Management: A History of Success and Failure. 1998. H.C. Dawkins and M.S. Philip

Agroforestry Systems -     

Consumption rate and susceptibility to parasitic nematodes and chemical molluscicides of the pest slugs Arion hortensis s. s. and A. distinctusJ. Iglesias, B. Speiser, Biological and chemical control of Arion hortensis s. l. slugs

The species complex Arion hortensis s.?l. is among the most important pestiferous slugs in Europe. The species A. distinctus Mabille and A. hortensis de Férussac have traditionally been grouped together under the denomination A. hortensis. Therefore, neither the feeding behaviour nor the susceptibility of the individual species to control measures are known. In the laboratory, mean daily consumption of lettuce was similar for both species. In a series of laboratory bioassays, A. distinctus and A. hortensis s.?s. were exposed to the rhabditid nematode Phasmarhabditis hermaphrodita and to the chemical molluscicides metaldehyde and iron phosphate, and their feeding and health were measured. Both species showed a similar and low susceptibility to the biocontrol agent P. hermaphrodita. In field-collected slugs, the incidence of nematodes was much lower in A. hortensis s.?l. than in Deroceras reticulatum or Arion lusitanicus. Metaldehyde and iron phosphate affected both slug species similarly. Therefore, our results do not indicate any major difference between the two slug species of agronomical relevance.     

长白山区大花卷丹的开发利用及园艺栽培技术

在吉林长白山池北区对区内分布的大花卷丹野生植株连续进行了5 a人工驯化栽培和物候观测,结果表明:充分气干种子的千粒重为5.707 g,播种量1.5 g·m-2左右,当年生苗高可达30～50 cm;在长白山区气候条件下,人工栽培群体的植株4月下旬开始萌芽,6月中旬现蕾,蕾期时间长达50 d;初花期为7月末,单花开放时间5...     

硒处理对泰山四叶参矿质元素及氨基酸含量的影响

采用盆栽试验研究硒处理对泰山四叶参矿质元素及氨基酸含量的影响,以期提高泰山四叶参营养品质。结果表明,硒处理降低泰山四叶参根干物质积累,硒处理浓度越高,干物质积累量越低。不同施硒处理后,泰山四叶参Mg含量明显提高,降低Ca、Fe、Mn含量,Zn、Se含量随施硒浓度的增大呈降一升一降的变化趋势且均于1．0mg／kg＋t处理时达到最大值。硒处理改善泰山四叶参所含人体必需氨基酸的含量,丙氨酸、异亮氨酸明显增加,以1．0mg／kg＋处理含量最高。1．0mg／kg十±处理有利于提高泰山四叶参保健价值。     

云南甜竹、大头典竹、吊丝单竹引种栽培试验研究

介绍了华安县1998年引种云南甜竹、大头典竹、吊丝单竹3个竹种的生长情况、经济效益和栽培技术。试验结果表明，其平均造林成活率和当年出笋率为：93．3％和85．9％，造林第2年就可郁闭成林，并有竹笋产出，第3年有竹笋、竹材产出，第4年达到稳定丰产期，每亩(1hm^2＝15亩，下同)平均产鲜笋l124kg、竹材45lkg，投入产出比为1：1．8。     

毛竹胸径分布和竹林生产力的估测

该文通过毛竹样地的胸径及枝下高调查，并运用电子计算机分析研究，结果表明：毛竹胸径、枝下高及鲜重的分布是遵从正态分布，这为毛竹林生产力的抽样及估测提供了理论依据。     

成龄金丝小枣树高接金丝新4号技术及效果调查

从2001年开始通过接穗的采集、收贮，对10a生的金丝小枣高接换头。经过8a的观察，该品种果实个大而整齐、品质优良、鲜食、制干品质极上，果实有很强的抗炭疽病、轮纹病的能力。嫁接第2年开始结果，667m^2产量152kg，第4年获得丰产，每667m^2产量达453kg，第5年以后高产、稳产。     

Differentiation of Prosopis juliflora (Sw.) DC. and P. pallida (H. & B. ex. Willd.) H.B.K. using foliar characters and ploidy

Two species of Prosopis, Prosopis juliflora and Prosopis pallida, native to Central America and northern South America, have been widely introduced and are now found throughout the world’s hot arid and semi-arid zones. However, these species are frequently misidentified, especially where introduced, hampering genetic improvement and effective management. Samples from trees previously identified as either P. juliflora or P. pallida were divided into two groups by multivariate analysis using selected foliar characters. One group contained known tetraploids and the other contained known diploids. It was concluded that the tetraploid and diploid groups correspond to P. juliflora and P. pallida, respectively. Triploid individuals were also identified, the first report of these in the genus Prosopis. A dichotomous key was developed to differentiate the species, using number of interfoliar glands per rachis, number of leaflet pairs per pinna and leaflet length. P. juliflora and P. pallida grown from seed collected within their respective native ranges were correctly identified using the key. Where introduced, samples from Burkina Faso, Jordan and India were confirmed as P. juliflora, but those from Brazil, Cape Verde and Senegal were identified as P. pallida, rather than P. juliflora, the species assumed to be naturalized in these countries. The correct identification of these two species will facilitate the genetic improvement and management of P. juliflora and P. pallida. There is a strong case for basing future selection and genetic improvement programs on P. pallida rather than P. juliflora. Further collection and evaluation of P. pallida is therefore required, together with conservation programs in the native range.     

杉木人工中幼林断面积及胸径自然生长初探

根据固定标准地调查材料，对中幼林杉木胸高断面积及胸径的自然生长进行分析表明：不同立地指数的杉木林分，其断面积及胸径自然生长是一组扩展的Ｒｉｃｈａｒｄｓ函数的多形曲线。     

春兰、豆瓣兰、莲瓣兰和春剑4种国兰种子萌发特性研究初报

采用无菌播种技术,对春兰、豆瓣兰、莲瓣兰和春剑4种兰属植物进行种子萌发试验。试验结果表明,种子萌发所需时间及萌发率与兰花种类及其果实成熟度、所选培养基等因素有关。春兰、豆瓣兰、莲瓣兰的种子萌发较易,而春剑较难;莲瓣兰种子萌发率较高;培养基A和C可促进豆瓣兰种子萌发,培养基B可促进莲瓣兰种子萌发,培养基A和B可促进春兰种子萌发。观察研究还发现,被1种细菌感染的兰花种子更易萌发。     

开化县林业资源现状与综合开发对策

针对开化县林业现状,提出了加快林业发展对策     

七里沙沙柳衰退原因及复壮更新措施的探讨

沙柳是一种重要的防风固沙树种，大面积生长于沙漠、沙地之中。近几年，随着工农业的发展，沙柳的需求量也在逐年增加。然而由于种种原因，现有沙柳林的衰退日益严重。本文结合实际情况，主要探讨了达拉特旗七里沙现有沙柳林的衰退原因及复壮更新的技术措施。     

南方红豆杉与云南红豆杉的引种栽培试验

研究在广东省惠州地区引种红豆杉科红豆杉属植物的营林技术，结果表明，南方红豆杉与云南红豆杉能够适应惠州地区的气候、土壤条件，且生长良好，有一定的发展潜力。但引种时需注意适时造林，防治白蚁，防治积水和干旱。     

黄栌和小叶白蜡的光合特征研究

黄栌(Cotinus coggygria Scop.)和小叶白蜡(Fraxinus bungeana DC.)是两种常见的园林树种,本文以黄栌和小叶白蜡为研究对象,研究了2树种的光合特性。结果表明:有光合"午休"现象净光合速率日变化曲线均呈现双峰型,有光合"午休"现象;在强光条件下,黄栌的净光合速率(Pn)、瞬时水分利用效率(WUE)、表观光能利用效率(LUE)和表观CO2利用效率(CUE)均高于小叶白蜡,证明黄栌对强光的适应性要高于小叶白蜡。     

早花柽柳的选育及栽培技术

＂早花柽柳＂是刘永军等人利用单株选优法历时4年从柽柳天然林中的选出的早花且花色艳丽的观赏类型。该品种是道路绿化美化、园林景观绿化中优良的配置材料。已通过宁夏林木品种审定委员会认定为＂林木良种＂。文章介绍了＂早花柽柳＂的选育过程、品种特性、栽培技术等。     

圣音竹引种培育技术研究

圣音竹地下茎乳白色,节间长15～24cm,横向水平状起伏生长。大小年较为明显,呈现大年长笋、小年长竹的生长规律。竹秆节间长4～6cm,株高仅为3～8m。直径与叶面积指数高度相关R=0.9966。竹林平均胸径1～2cm的最佳密度为5100～6000株/hm2,3～4cm的最佳密度为4500～5250株/hm2,4～5cm的最佳密度为3300～4200株/hm2。区域引种试验证明,圣音竹是一个可以广泛推广的优良竹种。