热带松树种、种源引种试验初报   总被引：1，自引：0，他引：1  

洪长福  黄文震  汤建福  郑德泰 《福建林业科技》2001,(Z1)

地处南亚热带的福建省长泰岩溪国有林场引种 5种热带松树的 7a栽培试验表明 :湿地松×加勒比松F1、F2 代生长均优于马尾松、湿地松 ;台库努曼松、马克西姆松与湿地松持平 ,各种源间初显差异。卵果松生长虽好 ,但抗逆能力差 ;墨西哥松基本不能适应新的环境  相似文献   

Methods for isolating the alder Phytophthora     

J.‐C. STREITO  G. JARNOUEN DE VILLARTAY  F. TABARY 《Forest Pathology》2002,32(3):193-196

Phytophthora disease of alder (Alnus spp.) is now widespread in Europe. In France, difficulties were initially encountered in attempts to isolate the pathogen from necrotic bark tissue but, with experience, a high degree of success was achieved by direct plating onto agar media. Both corn meal agar and a selective medium derived from PARBHy were satisfactory. Success depended largely on the activity of the fungus in the bark tissue and some evidence was obtained that this varied from year to year. However, autumn was found to be a generally good period for isolation. It is possible to store collected samples at 7 ± 4°C for some days. The alder Phytophthora was isolated from the water of two rivers with a baiting method using alder twigs but the efficiency of the method was low.  相似文献   

谈应用Photoshop cs软件绘制林业规划设计图的方法     

德灵胜 《林业勘查设计》2007,(4):79-80

介绍利用Photoshop CS软件绘制林业规划设计图,方法时尚、便于掌握、色彩鲜艳、成本低和效率高。在使用中,注意电脑系统、相关设备的配置;绘制方法和手段要正确;掌握一些技巧,才能充分发挥该软件的优越性,得到高质量的林业规划设计图。  相似文献   

Modelling daily catches of silver-phase European eel (Anguilla anguilla) in two hydropower-regulated rivers     

Eamonn S. Lenihan  T. Kieran McCarthy  Colin Lawton 《Fisheries Management and Ecology》2021,28(1):53-64

Estimation of silver eel production, Anguilla anguilla L., is fundamental for the management of eel stocks. In the hydropower-regulated rivers Shannon and Erne, Ireland, production is calculated using catch data from a conservation trap and transport programme. However, in both rivers gaps in silver eel catch datasets tend to occur, which can lead to biases in production estimates. Generalised additive models (GAMs) were used to model daily catch in these rivers based on a variety of environmental variables. Final models for the Shannon and Erne explained 83.7% and 78.8% of deviance in daily catch, respectively. A second model on the Erne included catch from a nearby fishing site in an attempt to increase explanatory power and explained 91.7% of deviance. Although model accuracy was increased, reliance on catch from another site may limit the applicability of the model. Model predictions were combined with estimates of fishing efficiency to predict production for the Shannon (36,210 kg; 0.85 kg/ha) and Erne (66,899–67,047 kg; 2.55–2.56 kg/ha). These values represented a 9.3% and 2.8%–3.0% increase on production estimated from incomplete catch records alone for the Shannon and Erne, respectively.  相似文献   

In Vitro Compaction of Germinal Vesicle Chromatin is Beneficial to Survival of Vitrified Cat Oocytes     

P Comizzoli  DE Wildt  BS Pukazhenthi 《Reproduction in domestic animals》2009,44(S2):269-274

The immature cat oocyte contains a large-sized germinal vesicle (GV) with decondensed chromatin that is highly susceptible to cryo-damage. The aim of the study was to explore an alternative to conventional cryopreservation by examining the influence of GV chromatin compaction using resveratrol (Res) exposure (a histone deacetylase enhancer) on oocyte survival during vitrification. In Experiment 1, denuded oocytes were exposed to 0, 0.5, 1.0 or 1.5 mmol/l Res for 1.5 h and then evaluated for chromatin structure or cultured to assess oocyte meiotic and developmental competence in vitro . Exposure to 1.0 or 1.5 mmol/l Res induced complete GV chromatin deacetylation and the most significant compaction. Compared to other treatments, the 1.5 mmol/l Res concentration compromised the oocyte ability to achieve metaphase II (MII) or to form a blastocyst. In Experiment 2, denuded oocytes were exposed to Res as in Experiment 1 and cultured in vitro either directly (fresh) or after vitrification. Both oocyte types then were assessed for meiotic competence, fertilizability and ability to form embryos. Vitrification exerted an overall negative influence on oocyte meiotic and developmental competence. However, ability to reach MII, achieve early first cleavage, and develop to an advanced embryo stage (8–16 cells) was improved in vitrified oocytes previously exposed to 1.0 mmol/l Res compared to all counterpart treatments. In summary, results reveal that transient epigenetic modifications associated with GV chromatin compaction induced by Res is fully reversible and beneficial to oocyte survival during vitrification. This approach has allowed the production of the first cat embryos from vitrified immature oocytes.  相似文献   

温度、光照和贮藏时间对珍珠梅种子萌发的影响     

熊翠翠  德永军  张健  王一  林涛  韦勤  张秀华 《内蒙古农业大学学报(自然科学版)》2012,(3):281-285

从温度、光照和贮藏时间等方面对华北珍珠梅和珍珠梅种子萌发特性进行了探讨。结果表明:不同光照条件对两种珍珠梅种子萌发影响较小,温度是影响珍珠梅种子萌发的主要因素;华北珍珠梅的最适发芽温度是25℃,珍珠梅的最适发芽温度是25℃～30℃,在此温度下发芽率和发芽势最高;一年之内,随着贮藏时间的延长两种珍珠梅种子的发芽率与发芽势均有小幅下降,发芽的高峰期推迟。  相似文献   

Biochemical and molecular basis of resistance to ACCase‐inhibiting herbicides in Iranian Phalaris minor populations     

J GHEREKHLOO  M D OSUNA  R DE PRADO 《Weed Research》2012,52(4):367-372

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Analysis of local spread of metamitron‐resistant Chenopodium album patches in Belgium     

J APER  E MECHANT  J DE RIEK  K VAN LAERE  R BULCKE  D REHEUL 《Weed Research》2012,52(5):421-429

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Effects of chloroacetamides and phytosynthesis-inhibiting herbicides on growth and photosynthesis in sunflower (Helianthus animus L.) and Amaranthus hybridus L.     

R. DE  PRADO  E. ROMERA  J. JORRIN 《Weed Research》1993,33(5):369-374

The effects of the chloroacetamide herbicides acetochlor, alachlor and propachlor and the pho-tosynthesis-inhibiting herbicides linuron, prometryn and terbutryn on sunflower (Helianthus annuus L.) and atrazine-sensitive and -resistant Amaranthus hybridus L. biotypes were investigated under laboratory conditions. Sunflower tolerated all three chloroacetamides in pre-emergence applications of 1.5–5.0 kg a.i. ha^?1 in growth assays. Sunflower also survived doses of 0.5–1.0 kg a.i. ha^?1 of linuron, prometryn and terbutryn, although growth reduction and chlorosis of treated plants was observed. These three herbicides inhibited photosynthetic electron transport in in vitro Hill reaction and fluorescence assays and, with terbutryn, photosynthesis recovered upon transfer of the leaves from herbicide solutions to water. The practical significance of these results for the control of weeds in sunflower cultivation in Spain are discussed. Effets d'herbicides chloroacétamides et d'herbi-cides inhibiteurs de la photosynthèse sur la crois-sance et la photosynthèse du tournesol (Helianthus annuus L.) et de Amaranthus hybridus L. Les effets des herbicides chloroacétamides acétochlor, alachlor et propachlor ainsi que des herbicides inhibiteurs de la photosynthèse linuron, prometryne et terbutryne, ont étéétudiés sur le tournesol (Helianthus annuus L.) et sur des biotypes sensibles et résistants d'Amaranthus hybridus L. en conditions de laboratoire. La croissance du tournesol n'était affectée par au-cun des trois chloroacétamides appliqués en prélevée (1,5–5,0 kg m.a. ha^?1). Le linuron, la terbutryne et la prometryne (0,5–1,0 kg m.a. ha^?1) occasionnaient des réductions de croissance et des chloroses sur le tournesol mais les plantes survivaient. Ces trois herbicides in-hibaient le transport d'électrons photosyn-thétique observé par des mesures de fluorescence et, in vitro par la réaction de Hill. Dans le cas de la terbutryne, la photosynthèse reprenait après transfert des feuilles des solutions d'herbicides dans 1'eau. La signification pratique de ces résultats pour la lutte contre les mauvaises herbes du tournesol en Espagne est discutée. Wirkung von Chloracetamiden und Photosyn-these-hemmenden Herbiziden auf Wachstum und Photosynthese der Sonnenblume (Helianthus annuus L.) und Amaranthus hybridus L. Die Wirkung der Chloracetamid-Herbizide Acetochlor, Alachlor und Propachlor und der Photosynthese-hemmenden Herbizide Linuron, Prometryn und Terbutryn auf die Sonnenblume (Helianthus annuus L.) und Atrazin-empfindliche sowie-unempfindl Amaranthus-hybridus-Biotypen wurde unter Laborbedin-gungen untersucht. In Wachstumstests tolerierte die Sonnenblume alle 3 Chloracetamide bei Vorauflaufanwendung von 1,5 bis 5,0 kg AS ha^?1. Auch Dosen von 0,5 bis 1,0 kg AS ha^?1 von Linuron, Prometryn und Terbutryn wurden vertragen, aber der Wuchs war beeinträchtig, und Chlorosen wurden beobachtet. Diese 3 Herbizide hemmten den photosynthetischen Elektronentransport bei Versuchen zur Invitro-Hill-Reaktion und Fluoreszenz, und bei Terbutryn stellte sich die Photosynthese nach Überführen der Blätter von der Herbizidlösung auf Wasser wieder ein. Die praktische Bedeutung dieser Ergebnisse für die Unkrautbekämpfung in Sonnenblumenkulturen in Spanien wird diskutiert.  相似文献   

Transmission of plum pox potyvirus in Spain1     

L. AVINENT  A. HERMOSO DE MENDOZA  G. LLCER 《EPPO Bulletin》1994,24(3):669-674

Transmission tests were conducted in the laboratory to determine which are the aphid species responsible for the great natural spread of plum pox potyvirus (PPV) observed in the field in Spain. Woody hosts were used in these tests and different transmission techniques were compared. The aphid species tested were Myzus persicae, Aphis gossypii, A. spiraecola, A. fabae, Hyalopterus pruni and Brachycaudus prunicola. Although the transmission rates obtained were, in general, quite low, it can be stated that, except for B. prunicola (pending confirmation of results), all species tested transmitted PPV under the conditions of the trial.  相似文献