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81.
Summary Wheat root characters which influence vital plant processes have scarcely been explored for their genetic control. This study was conducted to i) examine the diversity of root traits and associated shoot traits in spring wheat (Triticum aestivum L.) cultivars; ii) study the nature of genetic control of selected traits; and iii) examine associations among root and shoot traits. Three experiments were conducted in the greenhouse with plants grown in the vermiculite medium in clear plastic tubes. In the first experiment, 42 spring wheat cultivars were grown for three weeks and measurements were taken on root length, leaf length, root number, leaf number, root dry weight, and top dry weight. In the second study, 15F1's originating from a partial diallel mating of six cultivars along with the parents were evaluated for 4 weeks. The data on root length, leaf length, and root number were subjected to diallel analysis according to Griffing's method 4, fixed model. A third experiment consisted of studying 2 F2 populations with 141 plants per population. In the first study the 42 cultivars exhibited a wide range of variation for all six traits. Diallel analysis revealed significant effects of both general combining ability (GCA) and specific combining ability (SCA) for root length, leaf length, and root number. Parents with high GCA estimates were identified. Significant positive correlation coefficients were found among root and shoot traits. Analysis of F2's for root length indicated quantitative nature of inheritance of root length. 相似文献
82.
Summary Recent collecting activities have shown that Cuba is rich in plant genetic resources of lima beans. Seed characters of 173 Cuban accessions were measured. Principal component analysis and discriminant factor analysis were used to compare the accessions, which could be classified into seven groups: wild, weed, Potato, Potato-Sieva, Sieva, Sieva-Big Lima, Big Lima. The Sieva type is the principal group of Cuba. It has arrived to Cuba in pre-Columbian times via the Antilles arc. After the Conquest the Potato type was introduced from Central America. Introgressive hybridization with the Sieva group led to the intermediate Potato-Sieva type, whereas the Sieva-Big Lima type resulted from selection toward larger seeds within the Sieva group. The Big Lima type was introduced relatively late. Cuba occupies a key position in the distribution of Lima beans within the Americas and also to the Old World. 相似文献
83.
Pietro Perrino G. Battista Polignano Karl Hammer Christian O. Lehmann 《Genetic Resources and Crop Evolution》1984,32(4):197-206
Summary The mission was carried out within the Mediterranean Programme of the IBPGR in April/May 1983 with participants from the Socialist People's Libyan Arab Jamahiriya (Agricultural Research Centre, Tarabulus), the Istituto del Germoplasma, Bari, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben. In Tripolitania, the Fezzan- and Ghadmis-areas 316 samples, mostly cereals and vegetables, have been collected. In Tripolitania and the Ghadmis-area the land-races have been nearly completely replaced by new varieties. In the Fezzan genetic erosion is in progress. There, several cereal- and vegetable-land-races could still be collected. The land-races may be useful for breeding programmes.
Bericht über eine Reise in die Sozialistische Libysche Arabische Volksjamahiriya 1983 zur Sammlung autochthoner Sippen von Kulturpflanzen
Zusammenfassung Die Reise erfolgte im Rahmen des Mediterranean Programme des IBPGR im April/Mai 1983 mit Teilnehmern aus der Sozialistischen Libyschen Arabischen Volksjamahiriya (Agricultural Research Centre, Tarbulus), des Istituto del Germoplasma, Bari, und des Zentralinstituts für Genetik und Kulturpflanzenforschung, Gatersleben. In Tripolitanien, dem Fezzan und dem Gebiet von Ghadmis wurden 316 Proben, meist von Getrieden und Gemüsen, gesammelt. In Tripolitanien und dem Gebiet von Ghadmis sind die Landsorten fast vollständig von neueren Sorten verdrängt worden. Im Fezzan schreitet die Generosion fort. Hier konnten noch zahlreiche Getreide- und Gemüselandsorten gesammelt werden. Die Landsorten können für Züchtungsprogramme nützlich sein.
1983 .
— 1983 . ( .-. ), . , 316 , . . , . .相似文献
84.
Dr. K. Hammer M. Górski P. Hanelt F. Kühn W. Kulpa J. Schultze-Motel 《Genetic Resources and Crop Evolution》1981,29(1):91-97
Summary The wheat material of collecting missions to Czechoslovakia (in 1974 and 1977) and Poland (in 1976 and 1978) has been analyzed botanically and in respect to its possible breeding value by studying the original samples as well as their progenies grown up in the following years.The material represents populations of land-races and some old cultivars. Though there is a rapid genetic erosion in the collecting areas, the populations are very variable containing up to 6 botanical varieties. Some of the most variable land-races are described. In the populations ofTriticum aestivum land-races altogether 11 botanical varieties could be found, all with red grains. Exceptional findings are var.nigroferrugineum from the mountainous parts of Eastern Slovakia in 1977, and emmer wheat,Triticum dicoccon, from southern parts of Slovakia in 1974. The most promising characters for breeding purposes are short straw, winterhardiness, earliness, and field resistance against some diseases.In Gatersleben the land-races are separated into morphologically distinguishable types and maintained for their use in future breeding programmes.
Die Variabilität von Weizenlandsorten aus der SSR und Polen
Zusammenfassung Das Weizenmaterial der Sammelreisen in die SSR (1974 und 1977) und nach Polen (1976 und 1978) wurde botanisch und im Hinblick auf seinen möglichen züchterischen Wert anhand der Untersuchungen der Originalproben sowie ihres Nachbaus analysiert.Das Material besteht aus Landsortenpopulationen und einigen alten Sorten. Obwohl eine rasche Generosion in den Sammelgebieten zu verzeichnen ist, sind die Populationen sehr variabel und enthalten bis zu 6 Varietäten. Einige der variabelsten Landsorten werden beschrieben. In den Populationen vonTriticum aestivum-Landsorten konnten insgesamt 11 Varietäten gefunden werden; alle mit braunem Korn. Bemerkenswerte Funde sind var.nigroferrugineum aus den gebirgigen Regionen der östlichen Slowakei 1977 und Emmer,Triticum dicoccon, aus südlichen Gebieten der Slowakei 1974.Für züchterische Zwecke besonders aussichtsreiche Merkmale sind kurzer Halm, Winterfestigkeit, Frühreife und Feldresistenz gegenüber einigen Krankheiten.In Gatersleben werden die Landsorten in morphologische Typen aufgetrennt und für künftige Züchtungsaufgaben erhalten.
, (1974 1977 .) (1976 1978 .) , , ë , , . . , ë 6 . . Triticum aestivum , , 11 ; ë. var. nigroferrugineum 1977 . , Triticum dicoccon, 1974. : , , . .相似文献
85.
Conventional tillage winter wheat (Triticum aestivum) (WW)–summer fallow reduces soil productivity and increases soil erosion. Conservation tillage management, together with intensive cropping may have the potential to reverse these sustainability concerns. The objective of this study was to determine the effects of conventional tillage (CT) and no-tillage (NT) systems on grain yield of long-term annual cropping of monoculture WW, spring wheat (SW), and spring barley (Hordeum vulgare) (SB) grown with or without fertilizer, in the Pacific Northwest region of the USA. In unfertilized crops, grain yield of WW, SW, and SB was 15%, 25%, and 50% higher, respectively, in CT than in NT plots, an indication of the involvement of yield limiting factors under the NT cropping system. When fertilized, there were no significant differences in grain yield of WW. Yields of SW and SB, however, remained 21% and 15% higher, respectively, in CT than in NT, an indication that factors other than fertility were involved. These results suggest that in order for NT management to be widely adopted by area growers, the yield-limiting factors need to be addressed. 相似文献
86.
87.
Dr. Jürgen Schultze-Motel Dr. Reinhard Fritsch Dr. Karl Hammer Dr. Peter Hanelt Dr. Joachim Kruse Dr. Helga I. Maass Dr. Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1982,30(2):273-291
Summary Important papers on taxonomy and evolution of cultivated plants published in 1980 and 1981 were compiled and briefly discussed.
Herrn Prof. Dr. Dr. h. c. mult. H.Stubbe aus Anlaß der 80. Wiederkehr seines Geburtstages gewidmet. 相似文献
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1980/1981
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1980 und 1981 wurden zusammengestellt und kurz kommentiert.
: 1980–1981 .
, 1980 1981 . .
Herrn Prof. Dr. Dr. h. c. mult. H.Stubbe aus Anlaß der 80. Wiederkehr seines Geburtstages gewidmet. 相似文献
88.
89.
Jürgen Schultze-Motel Reinhard Fritsch Karl Hammer Peter Hanelt Joachim Kruse Helga I. Maass Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1990,38(3):417-434
Summary Important papers on taxonomy and evolution of cultivated plants published in 1988 and 1989 were compiled and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1988/1989
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1988 und 1989 wurden zusammengestellt und kurz kommentiert.
: 1988–1989
, 1988 1989 . .相似文献
90.
Sample populations of 157 Cannabis accessions of diverse geographic origin were surveyed for allozyme variation at 17 gene loci. The frequencies of 52 alleles were subjected to principal components analysis. A scatter plot revealed two major groups of accessions. The sativa gene pool includes fiber/seed landraces from Europe, Asia Minor, and Central Asia, and ruderal populations from Eastern Europe. The indica gene pool includes fiber/seed landraces from eastern Asia, narrow-leafleted drug strains from southern Asia, Africa, and Latin America, wide-leafleted drug strains from Afghanistan and Pakistan, and feral populations from India and Nepal. A third putative gene pool includes ruderal populations from Central Asia. None of the previous taxonomic concepts that were tested adequately circumscribe the sativa and indica gene pools. A polytypic concept of Cannabis is proposed, which recognizes three species, C. sativa, C. indica and C. ruderalis, and seven putative taxa. 相似文献