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1.
《广西农业科学》编辑部 《广西农业科学》2009,40(1):104-107
为了适应农业科研和生产发展的需要,《广西农业科学》编辑部在近年的办刊实践中积极探索,开拓创新,通过调整刊物定位向学术性期刊转变,增加版面和改进编辑流程缩短文章出版时滞,拓宽报道范围扩大影响力,加强与同行的交流学习,提升办刊理念,实行文稿校核质量控制体系,保证刊物质量,强化编辑队伍建设提高编辑人员业务素质,加强期刊经营增强期刊社经济实力等措施,使期刊的内外质量不断提高,社会效益和经济效益显著增强,期刊进入良性发展阶段。 相似文献
2.
L. Pülschen 《Journal of Agronomy and Crop Science》1992,168(4):249-254
Mixed cropping of leguminous underseed species and cereal crops may increase productivity and serve some additional purposes. Two leguminous weed species which are widely distributed in annual crops of the Ethiopian highlands have been studied with varying coverage in greenhouse trials in Ethiopia with regard to their suitability as underseeds and with wheat ( Triticum turgidum [L.] Thell. var. durum [Desf.] MacKey) as a main crop. The competitive effects of Scorpiurus muricatus L. on the grain yield of wheat were smaller than those of Medicago polymorpha L. (-14.1 % and -23.6 % respectively, compared with the underseed free control) which is mainly ascribed to differences in their speed of development and shoot height. The residual effects of the underseed's root masses on the grain yield of the successive teff crop (Eragrostis tef [Zucc] Trotter) were significantly higher with Scorpiurus muricatus (+99.3 %) than with Medicago polymorpha (+63.6 %). The results are discussed with regard to the specific site conditions in the cereal-dominated cropping systems of the Ethiopian highlands. 相似文献
3.
Randomized placebo-controlled crossover studies were carried out in dogs to evaluate how two non-steroidal anti-inflammatory drugs (NSAID) might modulate an acute post-traumatic inflammatory reaction. Two "identical" surgical interventions were performed on the forelimbs of each animal with an interval of 28 days, to enable a paired comparison of the inflammatory signs and the wound/bone healing processes. At one operation 8 dogs received 300 mg phenylbutazone twice daily for 8 days starting on the day before surgery, and at the other operation matching placebo tablets were given. In a similar placebo-controlled trial another group of 8 dogs received 5 mg indomethacin twice daily. With phenylbutazone the post-operative swelling was not significantly reduced compared to placebo, but there was less pain and limping. With indomethacin the swelling was somewhat reduced, but there was no consistent difference to placebo in the pain and limping assessments. None of the drugs appeared to distinctly effect the wound or fracture healing, as evaluated by clinical inspection, comparison of radiographs and comparison of bone sections from the sites of surgery. It proved difficult to select an appropriate dosage of indomethacin due to its high potential to induce GI ulceration and bleeding in dogs. In this experimental surgical model with an acute inflammation, neither phenylbutazone nor indomethacin showed impressive anti-inflammatory or analgesic properties. In the same model paracetamol has proved to significantly and more efficiently, reduce both swelling and pain without any noticeable adverse effects, and appears to be a better alternative than the two presently tested NSAID. 相似文献
4.
Comparison of the effects of salicylic acid and ethephon with virus-induced hypersensitivity and acquired resistance in tobacco 总被引:4,自引:0,他引:4
L. C. Van Loon J. F. Antoniw 《European journal of plant pathology / European Foundation for Plant Pathology》1982,88(6):237-256
The induction of a hypersensitive reaction in Samsun NN tobacco by tobacco mosaic virus (TMV) at 20°C leads to the development of both localized and systemic acquired resistance, and is associated with the appearance of pathogenesis-related proteins (PR's) and large increases in peroxidase activity and ethylene production. Salicylic acid (SA) induced a similar resistance in treated plant parts and occasionally also in untreated upper leaves of plants of which three lower leaves had been injected. SA also induced the same four PR's, but these were confined to the treated leaves. Thus, the connection between the presence of PR's and the reduction of TMV multiplication and spread may not be direct.In contrast to TMV, SA did not stimulate ethylene production and hardly increased peroxidase activity. Induction of acquired resistance and PR's by SA developed equally well at 20°C and at 32°C. However, pricking leaves with needles moistened with the ethylene-releasing compound ethephon mimicked TMV infection in inducing acquired resistance and PR's in both treated and untreated leaves at 20°C, but not at 32°C. Ethephon increased peroxidase activity at both temperatures, but only at 20°C dit it induce changes in both the anodic and the cathodic isoenzymes that were similar to those induced as a result of TMV infection. SA induced PR's and reduced TMV multiplication in Samsun tobacco, and inhibited virus spread in Samsun NN at 32°C.These observation indicate that neither the induction of PR's, nor the development of acquired resistance is temperature-sensitive. On the other hand, the effects of ethephon are temperature-sensitive in the same way as the hypersensitive response to TMV. It can thus be hypothesized that ethylene, produced naturally during the hypersensitive reaction of tobacco to TMV, leads to the temperature-sensitive synthesis or release of a presumably benzoic acid-type compound that functions as the natural inducer of PR's and acquired resistance. Although vanillic acid has been shown to accumulate in hypersensitively reacting tobacco leaves, it produced none of the effects of SA, and thus cannot be the natural inducer.Samenvatting Inductie van een overgevoeligheidsreactie in Samsun NN-tabak door tabaksmozaïekvirus (TMV) bij 20°C leidt tot de ontwikkeling van een verworven resistentie die zowel lokaal als systemisch werkzaam is, en gaat samen met het verschijnen van pathogenesis-related proteins (PR's) en sterke toename in de activitieit van peroxidase en de produktie van ethyleen. Salicylzuur (SA) induceerde een vergelijkbare resistentie in behandelde plantedelen en af en toe ook in niet behandelde bovenbladeren van planten waarvan drie onderbladeren waren ingespoten. SA induceerde ook dezelfde vier PR's, maar deze waren beperkt tot de behandelde bladeren. Er bestaat dus geen directe samenhang tussen de aanwezigheid van PR's en de remming van de vermeerdering en uitbreiding van TMV in de plant.In tegenstelling tot TMV stimuleerde SA de ethyleenproduktie niet en verhoogde het de peroxidaseactiviteit nauwelijks. Inductie van verworven resistentie en PR's door SA trad even goed op bij 32°C als bij 20°C. Net als infectie met TMV leidde aanprikken van bladeren met naalden die gedoopt waren in een oplossing van ethefon — waaruit in het blad ethyleen vrijkomt — echter tot inductie van verworven resistentie en PR's in zowel behandelde als onbehandelde bladeren bij 20°C, maar niet bij 32°C. Ethefon verhoogde de peroxidaseactiviteit bij beide temperaturen, maar alleen bij 20°C induceerde het veranderingen in zowel de anodische als de kathodische isoënzymen die vergelijkbaar waren met die welke geïnduceerd werden als gevolg van infectie met TMV. SA induceerde PR's en verminderde de vermenigvuldiging van TMV in Samsun tabak, en remde de uitbreiding van het virus in Samsun NN bij 32°C.Deze waarnemingen tonen dat noch de inductie van PR's, noch de ontwikkeling van verworven resistentie een temperatuurgevoelig proces is. Daarentegen zijn de effecten van ethefon op dezelfde wijze temperatuurgevoelig als de overgevoeligheidsreactie op TMV. Men kan daarom veronderstellen dat ethyleen, dat op natuurlijke wijze geproduceerd wordt tijdens de overgevoeligheidsreactie van tabak op TMV, aanleiding geeft tot een temperatuurgevoelig proces, namelijk de synthese of het vrijkomen van een verbinding, vermoedelijk een benzoëzuurderivaat, dat fungeert als de natuurlijke inductor van PR's en verworven resistentie. Hoewel is aangetoond dat vanillinezuur zich ophoopt in overgevoelig reagerende tabaksbladeren, veroorzaakte deze verbinding geen enkel van de effecten van SA. Vanillinezuur kan dus niet de natuurlijke inductor zijn. 相似文献
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在用棉花、大豆、花生功能叶饲养棉铃虫幼虫的基础上,测定各寄主功能叶的营养成分、木质素和纤维素含量,研究棉铃虫在取食不同寄主叶片后的生物学和营养效应。结果表明:1、取食棉花叶的生物学效应较好,取食花生叶的幼虫成活率下降,取食大豆叶的幼虫体重偏轻;2、取食棉花叶的营养效应较好,大豆叶最次;3、棉铃虫幼虫的食物转化率和食物利用率以棉花叶最高,棉铃虫嗜食棉花叶,在3种作物田同时存在的情况下,棉田被害最重。 相似文献
9.
桑树内源激素及其生理效应的研究进展 总被引:3,自引:2,他引:3
综述了近20年来桑树生长素、赤霉素、细胞分裂素、乙烯和脱落酸的研究进展。探讨了这五类激素在桑树生长发育和组织培养等方面的应用前景。 相似文献
10.
紫花苜蓿不同基肥配比效应的研究 总被引:1,自引:1,他引:1
针对云南紫花苜蓿Medicago sativa种植缺乏专用肥的研究,采用"3414"的试验设计来研究不同基肥配比对紫花苜蓿第1年产量、株高、叶茎比、单株质量的影响.试验得出,施N 57.3 kg/hm2、P2O5 138 kg/hm2、K2O 36.45 kg/hm2时年产最高,达104 865 kg/hm2;施N 129.3 kg/hm2、P2O5 -5.1 kg/hm2(视为不施磷肥)、K2O 82.5 kg/hm2时茎叶比最大,达52.12%;施N 79.35 kg/hm2、P2O5 73.05 kg/hm2、K2O 106.05 kg/hm2时株高最大,达61.56 cm;施N 24.9 kg/hm2、P2O5 79.05 kg/hm2、K2O 80.1 kg/hm2时单株质量最高,达5.58 g. 相似文献