广西骨碎补种质资源调查研究     

黄宝优  黄雪彦  彭玉德  韦莹  潘春柳  张占江 《湖北农业科学》2014,53(16):3832-3834,3839

采用走访和实地调查相结合的方法对广西优势药材骨碎补(Davallia mariesii Moore ex Bak.)种质资源种类与分布、生物生态学特性、资源及开发利用状况、有效成分含量等进行调查研究。结果表明,广西骨碎补种质资源丰富,基源植物共3科5属7种。骨碎补原植物喜温暖湿润的气候环境,多附生于林中岩石或树干上,偶生于墙上,土生较少。广西骨碎补药材品质佳,质量好,有较好的利用和开发价值。骨碎补生境受到一定程度破坏,资源逐渐减少,建议加强对骨碎补种质资源收集和原生境保护,开展种苗繁育和人工栽培技术研究,建立较大规模的人工种植与繁育基地,为资源可持续利用提供保障。  相似文献   

Dietary habits of grazers influence their suitability as biological controls of fouling macroalgae in ex situ mariculture     

Chin Soon Lionel Ng  Tai Chong Toh  Kok Ben Toh  James Guest  Loke Ming Chou 《Aquaculture Research》2014,45(11):1852-1860

The dietary habits of the sea urchin Salmacis sphaeroides and the gastropod Trochus maculatus in ex situ mariculture were examined. Fouling algal assemblages on terracotta tiles were exposed to the grazers and compared. Except for Day 0, the assemblages on Days 2, 13 and 27 differed significantly across treatments. S. sphaeroides rapidly consumed most algae, leaving an assemblage dominated by turf algae and bare tile. T. maculatus primarily fed on green filamentous algae, resulting in an even distribution of other algal functional groups, while control tiles were dominated by green filamentous algae. Using three representative fouling algae species (Bryopsis corymbosa, Hypnea spinella and Lobophora variegata), the consumption rates of both grazers and dietary preferences of S. sphaeroides were examined through a single‐diet and a choice experiment respectively. The single‐diet experiment revealed differential algal consumption rates for S. sphaeroides (H. spinella = B. corymbosa > L. variegata) and T. maculatus (B. corymbosa > H. spinella = L. variegata). The choice experiment showed that S. sphaeroides preferred H. spinella over the other two species. These experiments highlighted the importance of understanding the dietary habits of grazers as this has direct implications on their effectiveness as biological controls of fouling macroalgae in mariculture.  相似文献   

Effects of powdery mildew and weather on winter wheat yield. 2. Effects of mildew epidemics     

R. A. Daamen  I. T. M. Jorritsma 《European journal of plant pathology / European Foundation for Plant Pathology》1990,96(1):35-46

Wheat yield losses caused by powdery mildew were computed based on effects of the disease on leaf photosynthesis. Powdery mildew was introduced in a crop model of wheat by quantification of five parameters, taking the vertical and horizontal distribution of mildew in the crop into account. The most important parameters were those of the mildew intensity, the distribution of mildew in the crop, and the effect of mildew on assimilation at light saturation. Measured mildew epidemics in field experiments in three different years, were used to compute yield losses. Computed losses were compared to measured losses. On average, computed yield loss approached measured, but measured yield loss was underestimated, especially in early mildew epidemics due to the computation of partitioning and reallocation of assimilates. Other processes which may cause an underestimation are described. The use of crop models as a method to upgrade disease management systems is discussed.Samenvatting Opbrengstderving van wintertarwe werd berekend aan de hand van het effect dat meeldauw heeft op de blad-fotosynthese. Een rekenmodel voor de gewasgroei van tarwe werd uitgebreid met meeldauw. Met inachtneming van de vertikale en horizontale verdeling van meeldauw in het gewas, werd meeldauw in het model gekwantificeerd door vijf parameters. De belangrijkste parameters waren die van de meeldauwintensiteit, de verdeling van meeldauw in het gewas en het effect van meeldauw op de assimilatie bij een overvloed aan licht. Epidemieën van meeldauw, gemeten in veldproeven in drie verschillende jaren, werden gebruikt om opbrengstdervingen te berekenen. Gemiddeld kwam deze redelijk overeen met de in de veldproeven gemeten opbrengstderving. De gemeten opbrengstderving werd echter onderschat, vooral bij vroege epidemieën van meeldauw door de wijze waarop de (her)verdeling van assimilaten wordt berekend. Andere mechanismen, die een onderschatting van opbrengstderving kunnen veroorzaken worden besproken. Of deze modellen als methode gebruikt kunnen worden om systemen voor de geleide bestrijding van ziekten te verbeteren wordt bediscussieerd.  相似文献   

Effect of frugivorous birds on the establishment of a naturally regenerating population of Chinese yew in ex situ conservation     

Changhu LU  Qiongqiong ZHU  Qingshan DENG 《Integrative zoology》2008,3(3):186-193

The Chinese yew (Taxus chinensis) is catalogued as an endangered species in China because of the small size and senescent status of most populations. Its lack of natural regeneration is the most important reason for its endangered status. We investigated the regeneration of an ex‐situ conservation population, which was introduced into the Nanjing Botanical Garden Memorial Sun Yat‐Sen in the 1950s, and evaluated the role of frugivorous birds on the establishment of this regenerating population. Two hundred and thirteen individual yew seedlings and saplings were found on the hillside in 2006, and the nearest seedling was found more than 10 m away from mother trees. The spatial pattern of all seedlings and saplings occurred as a clumped distribution, which is typical for vertebrate‐dispersed plants. Six bird species were seen ingesting whole “fruits” at yew trees in the present study and 745 visits by avian frugivores were recorded. Red‐billed blue magpie (Urocissa erythrorhyncha), Chinese bulbul (Pycnonotus sinensis) and azure‐winged magpie (Cyanopica cyana) were the most frequent visitors over the two years of the study. Comparing the flights of departure and perching habitats of the three main bird species, we inferred that U. erythrorhyncha would be the most important disperser. This regeneration population has had good development over the past 20 or more years; frugivorous birds have removed seeds to the hillside every year until now, and seed germination and seedling growth continue to develop well under natural conditions. We suggest that the conservation system of the Chinese yew should be composed of yews, avian dispersers and habitats for seed germination and seedling growth.  相似文献   

Auxin-impregnated hygroscopic gel: effects on ponderosa pine and common hackberry seedlings     

Gerald A. Tuskani  Patricia L. Ellis 《New Forests》1991,5(4):359-367

Greenhouse and field studies were conducted to determine the effects of indole3-butyric acid (IBA) and 2,4-dichlorophenoxyacetic acid (2,4-D) on root development and survival of 3+0 bareroot Pinus ponderosa (Dougl. ex Laws.) and 2+0 bareroot Celtis occidentalis (L) seedlings. In the greenhouse, 100 and 200 ppm. IBA and 10 and 50 ppm 2,4-D were applied to seedlings through a root dip in an auxin hygroscopic gel mix. A randomized complete block analysis of variance indicated that IBA gel treatments increased root volume and root dry weight in hackberry and had no effect on ponderosa pine; 2,4-D gel treatments had detrimental effects on both species. In the field, IBA gel treated ponderosa pine seedlings exhibited improved height and survival relative to the non-treated control seedlings. There was no detectable improvement in survival in the field for hackberry. However, diameter and stem dry weight were lower for hackberry seedlings treated with the gel dip alone.  相似文献   

Durian trees (Durio zibethinus Murr.) in Javanese home gardens: their importance in informal financial systems     

Sandrine Dury  Laure Vilcosqui  Fabienne Mary 《Agroforestry Systems》1996,33(3):215-230

Home gardens used to be an important source of income and wealth for many Javanese rural households. In the wake of economic development and income diversification processes, their role is increasingly linked to credit needs. People borrow money by pawning (gadai) trees from home gardens. The tree harvest is at the disposal of the lender during the loan period. Analysis of more than 80 oral gadai contracts on durian trees in West Java demonstrates that the real interest rate is not usurious and can be compared to other formal and informal credit interest rates. It also shows that distributions of loan rates and loan amounts do not differ according to their final use (consumption or investment) or to the family relationship between the two partners of the transaction.  相似文献   

Geographical distribution of wild <Emphasis Type="Italic">Daucus</Emphasis> species in the natural grasslands of the Argentinian pampas     

E.  L. Camadro  M.  A. Cauhépé  P.  W. Simon 《Genetic Resources and Crop Evolution》2007,54(4):855-863

Three wild carrot species have been reported in the argentinian flora: Daucus montanus Humb. et Bonpl. ex Schult., D. montevidensis Link ex Sprengel and D. pusillus Michx. There is a discrepancy among authors about the distinctive morphological traits of the last two species; thus, it is difficult to ascertain if they are truly two distinct taxa. Based on the available literature and in the search of a paradigmatic site, four collection trips were carried out in 2004 and 2005 in Buenos Aires and Southern Entre Ríos provinces. Populations were sampled at 30 sites, and local environmental parameters and associated plant species were recorded. Morphological observations and chromosome counts were carried out on 10 plants/population. Three morphological phenotypes were distinguished: one in 18 populations, all with 2n = 2x = 18, and two in the remaining 12, with 2n = 2x = 22 or aneusomaty (2n = 2x = 20, 22). Populations of the first phenotype were assigned to wild D. carota and the rest, tentatively, to D. pusillus (D. montevidensis?), till further evaluations are carried out in test sites to verify this tentative conclusion.  相似文献   

不同氮与磷配比施用对桃儿七产量的影响     

刘世巍  丁建海  张守宗 《湖北农业科学》2012,51(18):4076-4078

通过对中药材桃儿七在定植前施用不同氮与磷配比组合的肥料试验,探讨了施肥对桃儿七产量的影响.结果表明,施用氮(N)75～225 kg/hm2、磷(P2O5) 150～225 kg/hm2,可获得较高的桃儿七产量,增产幅度比不施肥料的提高1倍以上;氮(N)与磷(P2O5)的配比在1∶1～1∶2,则桃儿七在田间的长势较好,增产效果明显,从投入产出比的角度来看也比较科学合理.建议在目前人工栽培桃儿七的大田管理水平前提下,采用氮(N)与磷(P205)的配比在1∶1～1∶2,于桃儿七定植前施入,可获得较佳的经济收益.  相似文献   

太子参药材总DNA提取研究   总被引：1，自引：1，他引：0  

王晓多  王晓玲  王晓丽 《安徽农业科学》2012,40(29):14167+14178

[目的]从太子参干药材中快速提取高质量基因组DNA。[方法]采用CTAB法和SDS法2种方法提取药材太子参干燥块根总DNA,并用紫外分光光度计和琼脂糖凝胶电泳检测。[结果]2种不同的提取方法均可从太子参中提取到一定纯度的DNA,其中CTAB法提取DNA的A260/A280>1.9,纯度和产率较高,蛋白质、多糖、RNA等杂志去除较为彻底。[结论]利用CTAB法可从太子参干药材中能快速提取到高质量DNA。  相似文献   

天全县毛竹实生林速生丰产配套技术研究     

梁秀清  苏贤文  涂绪中  王万金  王宇  杜作礼  杨仕银 《四川林业科技》2012,33(5):67-73

四川省天全县从2001年至2003年在17个乡镇发展毛竹实生苗造林14 466.67 hm2,至2006年郁闭成林,本文研究了毛竹成林到成材的前10 a生长主导因素。结果表明:毛竹造林用苗,宜用整窝实生苗。实生苗造林前5a主要是补植抚育保成活,最主要的措施是砍灌、除草、亮窝正苗。后5 a是成材的关键时期,主要措施是控制立竹度,保持4 500株·hm-2～10 500株·hm-2都可以,超过10 500株影响成材。施肥效应对成材影响不明显,毛竹苗从栽植到第8个年头,几乎都可以不施肥,以后施肥以P、K为主,每hm2在1500 kg以内即可;将四川毛竹造林海拨向上推进了200 m达到1 400 m。  相似文献