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1.
The issue of cross‐ or multiple resistance to acetolactate synthase (ALS) inhibitors and the auxinic herbicide 2,4‐D was investigated in Papaver rhoeas L., a common and troublesome weed in winter cereals, in a broad‐scale study across four European countries. A combination of herbicide sensitivity bioassays and molecular assays targeting mutations involved in resistance was conducted on 27 populations of P. rhoeas originating from Greece (9), Italy (5), France (10) and Spain (3). Plants resistant to the field rate of 2,4‐D were observed in 25 of the 27 populations assayed, in frequencies ranging from 5% to 85%. Plants resistant to ALS‐inhibiting herbicides (sulfonylureas) were present in 24 of the 27 populations, in frequencies ranging from 4% to 100%. Plants resistant to 2,4‐D co‐occurred with plants resistant to sulfonylureas in 23 populations. In four of these, the probability of presence of plants with cross‐ or multiple resistance to 2,4‐D and sulfonylureas was higher than 0.5. ALS genotyping of plants from the field populations or of their progenies, identified ALS alleles carrying a mutation at codon Pro197 or Trp574 in 2,4‐D‐sensitive and in 2,4‐D‐resistant plants. The latter case confirmed multiple resistance to 2,4‐D and ALS inhibitors at the level of individual plants in all four countries investigated. This study is the first to identify individual plants with multiple resistance in P. rhoeas, an attribute rarely assessed in other weed species, but one with significant implications in designing chemical control strategies.  相似文献   
2.
在罂粟果实膨大期,对正茬、迎茬、连作2 a、连作4 a处理的叶片光合生理生态参数进行了测定,旨在研究连作对罂粟光合作用的影响。结果表明:罂粟正茬、迎茬、连作2 a处理的光合速率日变化呈双峰曲线,具有明显的"午休"现象;连作4 a处理的光合速率变化呈单峰曲线.正茬、迎茬和连作4 a处理的光合速率下降(午休)是由气孔因素引起的,而连作2 a处理的光合速率下降(午休)主要原因是由非气孔因素引起的.正茬处理的光合速率显著高于迎茬、连作2 a和连作4 a处理的光合速率,分别高出2.71、2.28、2.31μmol/(m2.s).  相似文献   
3.
待供试转基因和非转基因野罂粟植株长至5~7片叶时,用微型喷雾器将不同浓度的卡那霉素溶液均匀喷施于叶片上,结果显示浓度为6.5g/L的处理表现效果最好。对于大田筛选转基因野罂粟,在苗期对叶片喷施6.5g/L卡那霉素溶液喷雾,并对产生黄斑的野罂粟植株进行剔除后,拔节期用7.5g/L卡那霉素溶液连续5d涂抹后,对产生黄斑的植株进行再次剔除,最终得到30株未见黄斑的野罂粟植株,经PCR进行检测后,最终得到8株野罂粟转基因植株。  相似文献   
4.
Alkaloid accumulation in capsules of the selfed and cross-pollinated poppy   总被引:2,自引:0,他引:2  
In harmony with international regulations the creation of poppy cultivars with high alkaloid content as well as free of alkaloids is in progress. In the course of selection procedures, five poppy cultivars of high chemical diversity, ‘Kheops’, ‘AT, ‘Tebona’, ‘Kék Gemona’ and ‘Przemko’, were selfed and crossed in two successive years (2000‐01). After full ripening, both the biomass production and the alkaloid content of capsules of selfed and crossed plants were determined. When the castrated alkaloid‐free cultivar ‘Przemko’ (accumulating only 0.01 mg/100 g morphine in capsules) was pollinated with cultivars rich in alkaloids, the morphine content of its capsules increased to 0.9‐7.5 mg/100 g‐values. Based on the well‐known biosynthetic background of poppy alkaloids, this can be explained by promotion of (S)‐norcoclaurine synthesis, which seems to be suppressed in alkaloid‐free plants; but tissues of the developing hybrid seeds, which contain a combined gene pool of both alkaloid‐free cultivar and that of the pollen donor plants, release this suppression. The chemical metaxenia also manifested itself in other combinations. In particular, the appearance of narcotine (0.1‐1.1 mg/100 g) in the narcotine‐free cultivars ‘Kheops’, ‘A1’ and ‘Przemko’ can be explained biochemically. If the narcotine‐type plants ‘Kék Gemona’ (accumulating 11.3 mg/g narcotine) were used for pollination, the developing seed tissue, which contains the gene pool of narcotine biosynthesis, might contribute to the suppression of the activity of 1,2‐dehydroreticuline reductase, which leads to the accumulation of narcotine at the cost of morphinanes.  相似文献   
5.
Arieh Levy 《Euphytica》1985,34(3):811-815
Summary Papaver bracteatum is a potential crop for the codeine industry. Seed shattering prevailing in the species is a major problem which reduces the seed yields. A spontaneous mutant with capsules having no pores of dehiscence was isolated in an experimental field. The seed yields of this shattering-resistant mutant are lower than in plants with normal capsules but the thebaine content of the capsules from the mutant is higher. The mutation is monogenic dominant; it can be used for breeding cultivars for dual purpose-thebaine and seeds.  相似文献   
6.
The variation in the seed shape, colour and yield, and content, yield and fatty acid composition of seed oil of 109 accessions of opium poppy Papaver somniferum, (majority of them Indian land races), was investigated. The seeds were white, pale yellow or light brown in colour, reniform or round in shape and varied in size up to three fold. The oil content, seed and the oil yield varied between 26 to 52%, 1.0 to 7.4 g/plant and 0.4 to 2.7 g/plant, respectively. The % content of palmitic, oleic and linoleic acid in the seed oil ranged between 9.3 to 40.0%, 7.5 to 58.4% and 0.7 to 72.7%, respectively. On average basis, the levels of major fatty acids in the seed oil were: oleic (37.1%) > palmitic (27.3%) > linoleic acid (17.2%). The palmitoleic, stearic and linolenic acids were present in the oils of only some of the accessions. Two of the accessions yielded linoleic acid rich seed oil of about the same quality as soybean and maize oils, and in four accessions, the proportion of palmitic, oleic and linoleic acids was roughly equal. The palmitic acid was relatively less and linoleic acid more in the seed oil from accessions rich in oil content. The oil that contained higher amount of oleic acid also contained higher amount of palmitic acid and relatively lower amount of linoleic acid. The correlation analyses revealed a strong positive relationship between seed yield and oil yield (r = +0.81), oil yield and oil content (r = +0.54) and oleic acid and palmitic acid content in the seed oil (r = +0.49), and a weak positive relationship between oil content and linoleic acid content of oil (r = +0.24), and a negative correlation was observed between oil content and palmitic acid content (r = –0.32), palmitic acid and linoleic acid (r = –0.55) and oleic acid and linoleic acid contents of oil (r = –0.68). The observations have permitted selection of accessions that are high seed and oil yielding and/or rich in linoleic, palmitic and oleic acids or containing palmitic, oleic and linoleic acids in about equal amounts.  相似文献   
7.
Downy mildew (DM) caused by Peronospora arborescens is the most destructive disease of opium poppy which assumes considerable importance in India and other poppy growing countries. The present study was aimed at identification and evaluation of stable resistance sources of DM in opium poppy. Furthermore, genetic variability and inheritance pattern of DM resistance has also been studied which can help in making strategy for crop improvement. Evaluation of 35 selected germplasm accessions of opium poppy under glasshouse and field conditions during the three consecutive years (2004–2005 to 2006–2007) resulted in identification of two genotypes (I-14 and Pps-1) as highly resistant and stable sources for DM resistance. Genetic studies of DM resistance revealed polygenic control with the dominance of susceptibility over resistance. Significant reciprocal differences were found largely due to maternal transmission of DM resistance indicating the involvement of cytoplasmic genes in addition to nuclear control. Analysis of genetic variability and selection parameters indicated predominance of additive effects for DM resistance and other yield contributing traits. Multivariate analysis resulted in classification of 35 selected accessions into 11 different clusters revealing very high level of diversity among the genotypes. Cluster analysis suggested that hybridization program involving genotypes from cluster V (which included highly resistant genotypes Pps-1 and I-14) and cluster IX (which included highly susceptible Jawahar-16 having good economically important traits like seed yield) could be expected to give best recombinants for improvement in terms of DM resistance and high seed and straw yield in opium poppy. Analysis of selection parameters like heritability and genetic advance also suggested that simple selection methods will be effective in stabilizing resistance traits following hybridization with high yielding genotypes.  相似文献   
8.
Opium is a narcotic obtained from opium poppy and raw materials of heroin for illegal drug trade. Information on opium production is important for governments and international communities to understand the scale of illegal drug trade and to implement drug fighting policies. Opium production can be estimated from opium yield and poppy cultivation acreage. Poppy cultivation acreage in turn can be estimated using remote sensing technique. This study explores the feasibility of assessing opium yield using remote sensing technique. The objective of this study is to find an effective biophysical indicator that can be related to both opium yield estimation and remote sensing measurements. Data are obtained from three years ground experiments conducted in an official farm in North-Western China. Opium yield and main plant and environmental parameters of opium poppy are measured. A linear regression analysis measures the relationship between opium yield and main plant parameters. A strong correlation between opium yield and leaf area index (LAI) in flowering and harvesting periods of opium poppy is observed (R2 = 0.826 and 0.862 respectively). LAI is a good indicator during flowering and harvesting periods and can be used to build a model for opium yield estimation. Furthermore, LAI can be retrieved using remote sensing at a region scale. The study shows that remote sensing could be used to estimate opium yield in opium poppy concentrated regions, and that a more comprehensive and precise opium production information could be obtained for further analysis of illegal drug circulating trend and policy.  相似文献   
9.
本文初步探讨了水分调控对罂粟不同生育时期地上主要器官吗啡含量的影响,实验结果表明,冬灌区现蕾期到盛花前期,随着灌水频率加大,罂粟壳中吗啡含量明显提高,盛花后期的连续灌水使罂粟壳中吗啡含量急剧下降,免冬灌区恰好相反,发育后期适当加大灌水频率和提高灌水量能明显的提高罂粟壳中的吗啡含量  相似文献   
10.
以罂粟为材料,研究不同浓度烯效唑对罂粟抗氧化酶以及可溶性糖含量的影响。结果表明:高浓度烯效唑处理对抗氧化酶各项指标的影响显著地高于低浓度处理;烯效唑处理后罂粟的可溶性糖含量随处理时间延长和处理浓度的升高而增加。  相似文献   
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