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21.
Animal manure and urine deposition can cause localized patches of high ionic strength (IS) soil in pastures, influencing plant production, nutritive value and sward composition. Chicory (Cichorium intybus L.) appears to thrive in high‐nutrient input situations, but no information is available on chicory response to increasing IS. In a greenhouse experiment, we evaluated the effect of rhizosphere ionic strength (0.9, 4.0, 8.0 and 12.0 dS m?1) on productivity and nutritive value of chicory. Dry matter production decreased linearly as IS increased. Shoot concentrations for Ca, Na and Cl increased as IS increased. All mineral concentrations, except Cu, were substantially higher than or equal to the highest concentrations reported for forages. At all IS, nitrate‐N and K exceeded maximum recommendation for ruminant diets. The sodium level could be high enough to reduce dry matter intake at the highest IS level. Crude protein and energy estimates indicate chicory would support production levels equivalent to those of other high‐quality forages. In vitro organic matter disappearance increased as IS increased. Chicory as a component of a forage mixture could help stabilize forage yield in pastures and also shows promise for use as a nutrient mop in feedlot areas, where excess soil nutrients are a problem.  相似文献   
22.
ABSTRACT

Excess nitrogen fertilization of leafy vegetables may cause undesirable accumulation of nitrates and a decrease in essential amino acids, resulting in a decrease in protein nutritional quality. We investigated the effect of nitrogen (N) fertilization (0, 100 or 200 kg N ha?1) on the nutritional quality of red head chicory proteins. Lysine limited biological value of proteins in the control (0 N) as well as fertilized samples. The lysine content and protein biological value according to Mitchell and Block method decreased significantly (p ≤ 0.05) with 100 and 200 kg ha?1 nitrogen applied relative to control. The Oser's essential amino acid index and protein biological value were relatively high and did not decrease with increased N fertilization. The correlation between the protein biological value of red head chicory and crude protein levels was negative (p < 0.001). Protein nutritional quality was optimal for adults and lower than optimal for children aged 2–5 and 10–12 years.  相似文献   
23.
The herbs chicory ( C ichorium intybus L.) and plantain ( P lantago lanceolata L.) are increasingly popular summer forage cropping options for dairy producers. However, the impact of different establishment methods on their productivity is largely unknown. Four establishment methods for chicory and plantain crops sown into non‐cultivated ryegrass pastures in spring were compared. Establishment methods included direct‐drilling or broadcasting seed into existing pastures, with or without herbicide application before sowing in a 2 × 2 factorial design. It was hypothesized that plant establishment and growth would be enhanced by spraying to kill existing ryegrass pasture and direct‐drilling herbs (Spray and Drill, SD) compared with broadcasting seed with no herbicide application (Unsprayed and Broadcast, UB). This hypothesis was supported with an additional 2·1–2·3 t DM ha?1 grown over 201 d from swards established by SD, compared with swards established by UB. The SD method also increased the plant density of the herbs and reduced the proportion of weed species. Spraying and direct drilling is more expensive than broadcasting seed with no herbicide application, but the increase in yield means that extra feed can be supplied at less than half the cost of purchasing the equivalent amount of feed. Therefore, for optimal economic outcomes, chicory and plantain swards should be established by applying herbicide to existing pasture and direct‐drilling seed.  相似文献   
24.
4份菊苣种质材料苗期抗旱性评价   总被引:1,自引:0,他引:1  
采取温室盆栽干旱胁迫方法,研究不同程度干旱胁迫对4份菊苣材料苗期11种抗旱性指标的影响。结果表明,随着干旱胁迫程度加重,菊苣叶片含水量及相对含水量、株高、生物量降低,叶片相对电导率、可溶性糖含量、游离脯氨酸、根冠比变化趋势比较明显,株高胁迫指数与干物质胁迫指数变化不大;综合分析认为叶片含水量、相对含水量、株高、根冠比、细胞膜透性、可溶性糖含量可以作为菊苣抗旱性评价的主要指标,地上生物量、地下生物量、株高胁迫指数、干物质胁迫指数、脯氨酸仅可作为菊苣抗旱性评价的参考指标。通过对11种抗旱性指标进行隶属函数法综合评价,得出4份菊苣材料抗旱性由强到弱的顺序为:C2>C1>C4>C3,该结果与田间观测结果相一致。  相似文献   
25.
为了对烟用菊苣(Cichorium intybus L.)进行提纯复壮和种植开发,建立从源头到产品的天然烟用香料控制保障体系,在云南石林开展了菊苣不同表型生长特性及其在卷烟中的应用研究。结果表明,生长表型为绿脉浅齿型(LMQC)、红脉浅齿型(HMQC)、红脉锯齿型(HMJC)3种,所占比例分别为35%、15%、50%。3种表型菊苣的植物学特征差异不大,同一时期抽薹率表现为:红脉浅齿型绿脉浅齿型红脉锯齿型;产量高低表现为:红脉锯齿型绿脉浅齿型红脉浅齿型,其中红脉锯齿型产量为16 480.5kg/hm2,与其余两个表型差异明显。感官评价以红脉锯齿型最佳。综合考虑,红脉锯齿型更适宜作为烟用菊苣进行推广种植。  相似文献   
26.
本文旨在研究菊苣提取物对蛋鸡生产性能、鸡蛋品质、肠道菌群、血清胆同醇和卵黄胆同醇的影响.300只尼克红蛋鸡随机分为5组,每组6个重复,每个重复10只,各组日粮中分别添加0、0.5%、1.0%、1.5%的菊苣提取物和1.0%的菊粉,试验进行4周.结果表明:与对照相比,不同水平的菊苣提取物或菊粉对蛋鸡产蛋率、蛋重、采食量、料蛋比、破蛋率、蛋黄重、蛋壳厚度和哈氏单位没有显著影响(P>0.05),但能显著降低鸡蛋胆固醇浓度(mg/g蛋黄)和含量(mg/蛋黄)(P<0.05),1.5%菊苣提取物添加组的动脉粥样硬化指数显著降低(P<0.05);日粮添加菊苣提取物或菊粉显著降低蛋鸡盲肠大肠杆菌数量和pH(P<0.05),1.5%菊苣提取物添加组和菊粉添加组显著增加盲肠双歧杆菌数量(P<0.05);鸡蛋胆固醇含量和盲肠大肠杆菌数量随菊苣提取物添加水平的增加线性降低(r=-0.957和r=-0.977)(P<0.05).结论:本试验在蛋鸡日粮中添加菊苣提取物或菊粉能显著降低鸡蛋胆固醇和盲肠有害菌(大肠杆菌)的数量,且不影响蛋鸡生产性能和鸡蛋品质.故在蛋鸡日粮中添加菊苣提取物或菊粉可为生产低胆同醇鸡蛋提供一条途径.  相似文献   
27.
BACKGROUND: As part of ongoing research for a sustainable production of Belgian endives, the fate of three fungicides during storage, handling and forcing of witloof chicory roots was investigated. Storage roots are protected against Sclerotinia sp. Fuckel and Phoma exigua var. exigua Desm. by means of vinclozolin and thiabendazole respectively. During hydroponic forcing, the most imminent pathogen is Phytophthora cryptogea Pethybr. & Laff., which is controlled by the use of dimethomorph. RESULTS: Vinclozolin and thiabendazole concentrations on roots remained constant during storage at ?1 °C. Dermal exposure of the workers in hydroponics was exceeded. Vinclozolin and thiabendazole residues were not detected 2 weeks after hydroponic forcing; dimethomorph was still detected at harvest. At harvest, the vinclozolin concentration in the chicory heads was below the maximum residue limit, but the chicory roots contained residues much above the thiabendazole and dimethomorph maximum residue level. CONCLUSION: Vinclozolin and thiabendazole residues applied before storage are still present on the roots at the start of the forcing cycle. During the set‐up of chicory roots, preventive measures are recommended, as effects of repeated human exposure to low doses of applied fungicides cannot be excluded. Dimethomorph applied at the start of the hydroponic forcing is the only pesticide detected in the drainage water at harvest. The chicory heads were safe for human consumption. However, more attention should be paid to the residues of fungicides in the roots used for cattle feeding. Copyright © 2009 Society of Chemical Industry  相似文献   
28.
BACKGROUND: Sclerotinia sclerotiorum (Lib.) de Bary is a major pathogen of witloof chicory. For lack of authorised field treatment, post‐harvest sprays with dicarboximide fungicides have been standard practice since the 1970s to prevent root rot and chicory heart decay during the forcing phase. However, the registration of procymidone and vinclozolin has been withdrawn in Europe. The development of organic agriculture and the necessity to reduce fungicide applications in conventional agriculture prompted an assessment of the efficacy of new fungicides and the use of the mycoparasite Coniothyrium minitans (Campbell). RESULTS: A mixture of the fungicides fludioxonil and cyprodinil (Switch®) applied on chicory roots achieved a very good control of S. sclerotiorum (up to 95%). The use of C. minitans limited root infection, both when applied in the field (50–65% efficacy) and before the forcing period (post‐harvest treatment up to 80%). CONCLUSION: In organic agriculture, two treatments with C. minitans (in field and later at the forcing period) could improve protection against S. sclerotiorum. In conventional agriculture, after the field biological treatment, a post‐harvest chemical treatment could be applied. The addition of other prophylactic methods could lead to a high level of performance in practice against decay caused by S. sclerotiorum. Copyright © 2010 Society of Chemical Industry  相似文献   
29.
农杆菌介导普那菊苣遗传转化体系的建立   总被引:1,自引:0,他引:1  
以普那菊苣(Cichorium intybus L.cv.Puna)叶片为试验材料,接种于含不同激素浓度配比的MS培养基上进行愈伤组织、芽分化以及根再生的诱导,分析了不同激素浓度及其配比对愈伤组织诱导和芽分化以及根再生效果的影响。以已经建立的再生体系为基础,以农杆菌菌株LBA4404(含质粒pBin438-TaNHX2)侵染转化普那菊苣,探索普那菊苣高效遗传转化体系。结果表明:对外植体适宜的预培养时间为2~3d,与农杆菌的共培养时间也应控制在2~3d;侵染时间控制在8min左右;卡那霉素(Km)阳性筛选的适宜选择浓度为60mg·L-1。乙酰丁香酮(AS)200μmol·L-1是促进农杆菌转化的最佳浓度,200 W超声波处理、20次负压处理也可提高农杆菌转化率效果。26mg·L-1 Km是野生型普那菊苣苗能够存活的上限,头孢唑林钠和头孢噻肟钠在500~1000mg·L-1浓度范围内、羧苄青霉素300mg·L-1和氨苄青霉素在40~60mg·L-1浓度范围内均能较好的诱导出愈伤组织和芽。将来自小麦(Triticum aestivum)的Na+/H+逆向转运蛋白(vacuolar Na+/H+exchanger or antiporter,简称NHX,NHE或NHA)导入普那菊苣;经抗生素筛选以及针对TaNHX2基因的PCR检测和Southern杂交分析,证明获得了28株转TaNHX2基因的普那菊苣植株。  相似文献   
30.
The milk-production potential of different sward types was measured in each of the four seasons of the year in a replicated experiment in south-west Victoria, Australia. Dairy cows were offered ad libitum allowances of a 'short-term winter' sward, based on Italian ryegrass (treatment STW), a 'long-term winter' sward, based on a winter-active tall fescue (treatment LTW), a 'long-term summer' sward, based on a summer-active tall fescue (treatment LTS) and a Control sward (perennial ryegrass) in four seasons (days in milk in parentheses): spring (November dairy cows, 124), summer (February, 227), autumn (May, 234) and winter (August, sixty-four). A 'short-term summer' sward, based on chicory and white clover (treatment STS), was also included in summer. There was a significant season × treatment interaction caused by a more gradual decline in milk yield from peak for cows grazing treatment LTS compared to the Control treatment in the transition period from spring to summer. In summer, cows grazing treatment STS produced more milk (1·41 kg fat plus protein per cow d−1) than cows grazing all other treatments (0·92 kg per cow d−1) because of the superior nutritive value of herbage of pre-grazing pasture and higher apparent dry-matter intakes. Swards based on alternative species to perennial ryegrass are capable of supporting milk production that is at least comparable over an annual cycle.  相似文献   
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