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1.
Crop losses caused by environmental stresses might be reduced by applying osmoprotectans to crop canopies. Glycinebetaine is endogenously accumulated by some halophytes under stress conditions and represents such a compound. Glycinebetaine was applied exogenously to barley ( Hordeum vulgare L.), oat ( Avena sativa L.), spring wheat ( Triticum aestwum L.), and summer turnip rape ( Brassica rapa ssp. oleifera DC.) canopies and its optimal concentration was monitored in the greenhouse. In field experiments the response of crop plants to betaine applications was assessed by measuring accumulation of above ground biomass, leaf area index (LAI), leaf chlorophyll, and yield. The optimum betaine concentration producing advantageous effects on growth and crop physiology in turnip rape was close to 0.1 M and for wheat 0.3 M. Such concentrations promoted accumulation of betaine similar to that of halophytes under stress conditions [ca. 200 μmol (g DM)−1]. In the 1993 field experiment peak LAIs were recorded in irrigated wheat and barley treated with 17.5 kg ha−1 betaine applied at 300 1 ha−1. Green leaf area was slightly more persistent in wheat treated twice with 1 kg ha−1 betaine applied at 200 1 ha−1 in 1994, although it was not associated with increased grain yield. Our results indicated that betaine has no actual potential in Finland for the principal grain crops but further studies are needed in stress prone environments to assess the potential of betaine treatments for preventing crop failures.  相似文献   

2.
Unknown compounds in crop plants are inhibitory to seed germination and early seedling growth of weed plants. A Petri dish assay showed that barley (Hordeum vulgare L.), oats (Avena sativa L.), rice (Oryza sativa L.) and wheat (Triticum aestivum L.) extracts significantly reduced root growth of alfalfa (Medicago sativa L.), barnyard grass (Echinochloa crus‐galli, Beauv. var. oryzicola Ohwi.) and eclipta (Eclipta prostrata L.). As the concentration of crop extracts increased, root growth of the test plants were significantly reduced. A high‐performance liquid chromatography analysis with nine standard phenolic compounds showed that the concentrations and compositions of allelopathic compounds depend on the extracted plant extracts. Caffeic acid, hydro‐cinnamic acid, ferulic acid, m‐coumaric acid, p‐coumaric acid and coumarin were present in all the crop plant species, and hydro‐cinnamic acid were detected as the highest amount. Coumarin at 10?3 m significantly inhibited root growth of alfalfa and barnyard grass more than that of eclipta. The research suggests that extracts of barley, oats, rice and wheat have an allelopathic effect on alfalfa, barnyard grass and eclipta and that the findings of bioassay were considerably correlated with the type and amount of causative allelochemicals, indicating that the allelopathic effects on three test plants were ranked in order of wheat (highest), barley, rice and oats (lowest). The results may have value in enabling weed control based on natural plant extracts or crop residues in the fields.  相似文献   

3.
大麦β-淀粉酶活性对其种子在干旱胁迫下萌发影响的研究   总被引:1,自引:0,他引:1  
为了鉴选出抗旱性较强的大麦品种,并以期找出β-淀粉酶活性对大麦抗旱性的影响,对β-淀粉酶活性不同的9个啤酒大麦品(系)种进行聚乙二醇(PEG-6000)模拟干旱胁迫,通过对种子发芽率及发芽势的测定来评价参试品种的抗旱性,并对β-淀粉酶活性与不同PEG浓度下的发芽率进行相关分析。结果表明,大麦β-淀粉酶活性与大麦抗旱性在PEG浓度为15%时,在0.01水平上达显著正相关。大麦种子发芽率随着干旱胁迫程度的增加而降低。5%浓度的PEG对大麦种子的萌发影响较小,10%、15%浓度显著抑制大麦种子萌发,20%浓度下,大麦个别品种发芽停止。处理样品间,‘沪麦16’综合表现出较好的抗旱性,其次A7-30,而‘邯98-58’、‘盐95137’为最差。由此得出,10%的PEG干旱胁迫剂浓度可作为大麦发芽期判断大麦抗旱性的适宜胁迫浓度,β-淀粉酶活性可作为大麦抗旱性早期筛选的指标之一。  相似文献   

4.
Effect of fungicides on fungus diseases and on the quality of the spring barley ( Hordeum vulgare L.) in the subalpine area of Slovenia
The 1000 kernel weight of brewer's spring barley can be enlarged by using fungicides triadimephone or propiconazole. Propiconazole has better effects on the net blotch. The both fungicides reduce protein contents, however, these alterations hasn't great practical value. By using the above mentioned fungicides, the yield of spring barley was statistically remarkably higher that that of unsprayed control. The 3 years average yield of cv. Kraguj sprayed with propiconazole was statistically remarkable higher than any other cultivar in any other experimented variant.  相似文献   

5.
Waterlogging on croplands is increasing in various areas of the world. This study evaluated the yield penalty by early and late waterlogging on wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), rapeseed (Brassica napus L.) and field pea (Pisum sativum L.). Plants cultivated outdoors were exposed to a 14-day waterlogging during vegetative (at 65 days after sowing (DAS)) or reproductive (at 85/87 DAS) stages, followed by drained conditions until maturity. Yield (seed weight per plant) and its components (number of spikes/siliques/pods per plant, number of grains per spike/silique/pod and 1,000 grain weight) were assessed at maturity, along with morphological (number of tillers/branches) and shoot and root dry weight responses after waterlogging and during recovery. Wheat was the most tolerant species achieving 86% and 71% of controls in yield with early and late waterlogging, related to fewer grains per spike. Barley and rapeseed tolerated early waterlogging (yields 85% and 79% of controls) as compared to late waterlogging (32% and 26% of controls), mainly due to fewer spikes per plant (barley) or reductions in seeds per silique (rapeseed). Field pea was greatly affected by waterlogging at both timings, attaining a yield of only 6% of controls on average due to much fewer pods and fewer seeds per pod. So, wheat could be an option for areas facing either winter or spring transient waterlogging (i.e. early or late stages); barley and rapeseed are recommended only with if water excess occurs in early stages and field pea is intolerant to waterlogging.  相似文献   

6.
A field experiment was conducted during July 1986–April 1988 at New Delhi, to evaluate the relative contribution of rainy-season legumes towards the growth and productivity of succeeding wheat ( Triticum aestivum [L.] emend. Fiori & Paol), find out economic optimum dose of nitrogen for succeeding wheat and screen a legume which can be best knitted in wheat based cropping system.
HD 2329 wheat performed better when grown after legumes than when grown after Local fodder sorghum ( Sorghum bicolor [L.] Moench). N economy in wheat was greater (65–78 kg/ha) after Sona clusterbean ( Cyamopsis tetragonoloba [L.] Taubert) and T-9 blackgram ( Phaseolus mungo L.) over sorghum. The economic optimum dose of N for wheat following pigeonpea ( Cajanus cajan [L.] Millsp.), soybean (Glycine max [L.] Merr.), groundnut ( Aracbis bypogaea L.), blackgram ( Phaseolus mungo L.) and clusterbean were 110.1, 103.6, 113.7, 109.6 and 92.3 kg/ha respectively.  相似文献   

7.
通过室内生物测定法,研究了黄芪根水浸液对4种作物种子萌发及幼苗生长的化感影响。结果表明,黄芪根水浸液对4种作物种子萌发及幼苗生长均有明显的化感作用,其中根受到的化感抑制大于地上部分,种子萌发阶段受到的化感抑制大于幼苗生长阶段。不同受体的发芽势、最长根长和根冠比受到的化感抑制最强。4种作物的化感敏感性为小麦>板蓝根>大麦>大豆。因此,选择与黄芪轮作、套作的作物时,优先选择大豆和大麦,其次为板蓝根。  相似文献   

8.
To evaluate the variability among cultivars and landraces of common bean(Phaseolus vulgaris L.), 15 cultivars and 18 landraces of common bean (Phaseolus vulgarisL.), a undefined species of Phaseolus,two landraces of Vigna angularis L., and a landrace of soybean (Glycine maxL.), were screened with fifteen oligonucleotide primers in PCR reactions. An average of 20.3 RAPD bands were scored per primer. A total of 304 amplification products were scored of which 88.8% were polymorphic among Phaseolus genotypes. Based on the RAPD markers, four major clusters were formed. Three clusters corresponded to the soybean, to the two Vigna angularis landraces, and to the Phaseolus sp. landrace, respectively. The fourth cluster include all the landraces and cultivars of Phaseolus vulgaris. This large group could be separated into three subgroups that were correlated with the phaseolin patterns and the average seed weight of the genotypes. The analysis shows that most of the landraces collected in South Brazil (17 out of 18) belong to the Andean gene pool, and most of the cultivars (13 out of 15) belong to the Middle American gene pool. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

9.
Comparative osmotic adjustments in barley and tetraploid wheats   总被引:3,自引:0,他引:3  
B. Teulat    D. Rekika    m. m.  nachit p.  monneveux 《Plant Breeding》1997,116(6):519-523
Five barley (Hordeum rulgare L.), five durum wheat (Triticum turgidum concar. durum L.) and one wild emmer wheat (Triticum turgidum conrar dicoccoides) genotypes from different origins and differing for drought tolerance and potential yield, were studied for their osmotic adjustment capacity at the same stage and under similar water stress conditions. Differences for water status parameters between barley and tetraploid wheat genotypes were noted and discussed. The lowest osmotic adjustment capacities were noted in drought susceptible varieties, while a high capacity was found in genotypes exhibiting a high yield stability across contrasting environments. Relative water content, leaf osmotic potential and accumulation of soluble sugars were found to be highly related with osmotic adjustment: they could be used as criteria for a rapid evaluation of osmotic adjustment in segregating populations.  相似文献   

10.
N.J. Kilby  J. Robinson 《Euphytica》2001,120(2):265-272
Rhynchosporium secalis (Oud.) J.J. Davis, causal agent of scald of barley (Hordeum vulgare L.), was isolated from barley, couch grass (Elymus repens L.) and rye (Secale cereale L.). Isolates were used to inoculate seedlings of a differential barley series containing several sources of major gene resistance to the disease. The series included Atlas46, (resistance gene Rrs1) and the isogenic line Atlas, which lacks the gene (rrs1). The necrosis-inducing peptide NIP1 has been suggested to be the product of the avirulence gene AvrRrs1 (NIP1) that with the barley resistance gene Rrs1 determines the incompatibility of the pathogen-host interaction. All R. secalis isolates were virulent only on the susceptible barley cultivars Arve and Chan, irrespective of spore concentration or original host species. There were no indications of redundant virulence among the R. secalis isolates. The NIP1 gene was sequenced from each isolate and there was no correlation with source of the isolate or sequence modification and virulence. Four isolates, from barley and couch grass, were characterised by a basic Type I NIP1sequence. The recorded NIP1 sequence changes are consistent withR. secalis populations not receiving selection through deployment of the Rrs1 gene in commercial barley cultivars in Finland. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

11.
为了阐明紫色土上接种丛枝菌根真菌(arbuscular mycorrhizal fungus,AMF)和不同间作方式对提高间作玉米(Zea mays L.)、大豆(Glycine max L.)的氮素利用和减少土壤氮残留的贡献。本试验在设施盆栽条件下,采用根系分隔模拟装置研究玉米/大豆间作体系中根系不分隔、尼龙网分隔、塑料膜分隔3种方式和不同AMF处理[不接种AMF(NM)、接种Glomus mosseae(GM)]对玉米、大豆植株生长、氮素累积与利用的影响。研究结果表明:接种GM不同程度提高了间作玉米和大豆根系菌根侵染率、株高、植株生物量及氮含量,而显著降低了玉米和大豆种植土壤的碱解氮含量。其中,GM-根系不分隔处理玉米、大豆的菌根侵染率最高。无论是否接种AMF,大豆生物量和植株氮含量均以根系分隔处理显著高于不分隔处理,而玉米生物量和植株氮含量却刚好相反。此外,GM处理条件下,玉米、大豆根际土壤碱解氮含量均以尼龙网分隔和不分隔处理显著低于塑料膜分隔处理。在所有复合处理中,以GM-根系不分隔处理对玉米生长及氮素累积的促进作用最好;GM-尼龙网分隔处理对大豆生长及氮素累积的促进效果最佳,并更能显著降低玉米、大豆根际土壤的碱解氮残留,可望减轻土壤氮流失而降低氮素流失对地表水体的污染风险。  相似文献   

12.
Penetration resistance, root length density, and water content of soil with maize (Zea mays L.), soybean (Glycine max [L.] Merr.), or a mixture of alfalfa (Medicago sativa L.) and fescue (Festuca arundinacea Schreb.) were measured during two summers, one of which was dry. Plants grew on a silt loam (Mollic Albaqualfs; fine, mixed, thermic), 0.25 m deep overlying a claypan, 1.75 m thick. Half of the plots were subsoiled before planting in the first year of the study and the other half were not subsoiled. During both years, subsoiling had no measurable effect in lowering the penetration resistance in the claypan. Root length density was greater in the claypan than in the topsoil. Subsoiling did not increase root length density in either year. Water content in plots that had been subsoiled was usually similar to that in plots that had not been subsoiled. In the dry year, roots of maize proliferated more in the claypan than did roots of soybean or alfalfa + fescue.  相似文献   

13.
Nitrogen (N) fertilizer is an important and expensive input in small-grain cereal production, and growers therefore should aim to optimize its use. Possibilities for using grain protein concentration for post-harvesr evaluation of N sufficiency were determined in this study. Field experiments including spring wheat ( Triticum aestivum L.), spong barley ( Hordeum vulgare L) and spring oats ( Avena sativa L.), and various rates of N fertilizer application were conducted in southern and western-Finland over 2 years. Grain yield and grain protein were positively correlated and firred quadratic regression models. Both critical and optimum levels for grain protein concentration were determined by Cate-Nelson analysis Critical values were 12.2 for wheat, 10.2 for barley and 10.9 for oats, and corresponding optimum values were 13.3, 11.1 and 12.7, respectively. The accuracy of the method was tested using results from on-farm spring wheat trials. The results indicated that N fertilizer uptake and grain yield were best in held where gram protein concentration exceeded the critical values but not the optimum. Growers should use more intensive N fertilization management if grain protein concentration does not exceed critical values. Grain protein concentrations above optimum values indicate over-fertilization for maximum grain yield. Analysing previous research data to identify the "critical level" of grain protein concentration is not difficult, and will provide powers, extension personnel, and fertilizer dealers with a cost effective means of evaluating the efficiency of N use by the crop and for developing N fertilization recommendations.  相似文献   

14.
水分胁迫下钙对大豆叶片光合作用的改善效应   总被引:21,自引:0,他引:21  
杨根平  高向阳 《作物学报》1995,21(6):711-716
本工作采用控制营养液中的钙量和叶片喷钙的方法来提高植株的钙水平,研究了钙对水分胁迫大豆光合作用的效应,结果表明:在水分胁迫下,经高钙处理(14mmol/L Ca^2+)大豆叶片保持高的光合速率;中钙(5mmol/L Ca^2+)处理次之;低钙(营养液中不加Ca(NO3)2,而以NaNO3代之)处理一周叶片光合作用速率最低,相对变化最大,在同样程度的水分胁迫下,高钙处理叶片具有较高的CO2羧化效率,  相似文献   

15.
Morphological features of the cereal ear, including awns, alter pre-harvest sprouting damage by changing the rate of water absorption during rainfall. In this paper, the potential for wheat (Triticum sp.) arid barley (Hordeum vulgare L.) waxes to reduce sprouting by increasing water repellency of the mature ear has been examined. Six barley F2 populations segregating for different non-glaucous single-gene mutants controlling waxes on ears were examined. Water repellency was assessed by measuring both the contact angle of a water drop placed on the lemma surface (internal angle) and by repetitive weighings of whole ears during their exposure to simulated rainfall. The lemma of glaucous (wild type) lines had larger water drop contact angles, an indication of poorer spread of water over the surface. In simulated rainfall, ears of the glaucous lines showed a clear reduction of wetting (20–30% less) and, after 72 h of wetting, their in-ear sprouting was reduced by 50 to 65%. When pre-wet, the glaucous ears also shed water more readily when shaken to simulate the combined effect of wind and rainfall. To reduce pre-harvest sprouting of barley it may be possible to screen visually for ears that are more glaucous but a more specific screen would be to select for lemma water drop contact angle since it is a good indicator of ear wettability and so allows differences in surface properties to be assessed. For bread wheat (T. aestivumL.), as for barley, the more glaucous the ear, the greater the water drop contact angle and the more tubular surface wax coverage seen in scanning electron microscope images. In addition, surface wax amount apparently affected in-ear wettingin lines of durum wheat, (T. turgidum L.). Possible genetic relationships between waxy/waxless genes in wheat and barley are suggested with the aim, ultimately, of altering ear glaucousness to give increased water repellency and a reduction of in-ear sprouting of wheat. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

16.
Effect of field bean and soybean cultivation on soil compaction amelioration and its influence on wheat and barley as subsequent crops
Amelioration effect of field bean and soybean growth on compacted soil and its influence on the following crops of wheat and barley was tested. The performance of both field bean and soybean was affected by compaction. A reduction of 5–16 % in total dry matter, 10–22 % in seed yield, 5–12 % in no. of pods per plant, 4–14 % in plant height, 8–19 % in total accumulated N in plant and 11–22 % in accumulated N in seed of the both crops was registered. The crops were grown at 30 and 60 plants/m2 densities. The negative effects of compaction were compensated to some extent by high plant density. Both crops loosened the compacted field, the effect increased with an increase in plant density. Field beans decreased the soil bulk density up to 8 %, increased total porosity up to 8 % and air filled pores up to 19 % till 30 cm soil depth, the effects being higher than produced by soybeans.
The increases in yields of wheat and barley and in their accumulated N were 9–57 % and 11–56 %, respectively after field bean and soybean as preceeding crops than after barley.  相似文献   

17.
以96对SSR引物对BC3F2群体进行辅助筛选,构建了一组基本覆盖野生大麦ISR42-8染色体,并导入轮回亲本Scarlett的1H~7H全基因组的外源基因渗入系,为大麦QTL精细定位提供了良好的作图群体。这组渗入系一共66个,目标片段平均长度为27.6 cM,最长的系IL-52片段长度为100.5 cM,最短的系IL-50片段长度为1.5 cM。含单个渗入片段的有33个系。聚类分析结果表明,66个渗入系的遗传背景高度相似,遗传相似系数变幅为0.708~1.000,平均值为0.917。检测到一个位于4H染色体87.5 cM到110.0 cM区间的分蘖相关QTL,长度为22.5 cM,其中包含多态标记MGB396。  相似文献   

18.
A relay cropping system of cereals, whereby winter wheat (Triticum aestivum L.) was undersown in two‐row spring barley (Hordeum distichum L.), was established in a field trial in central Sweden in 1999 and continued until 2000. The purpose of the study was to examine crop and weed responses to different plant densities of the undersown winter crop. Winter wheat was sown at four seed rates (187, 94, 47 and 0 kg ha?1) immediately after the sowing of barley. Barley was harvested in the first autumn after sowing and winter wheat in the second autumn. The grain yield of barley was not affected by the seed rate of wheat, and averaged 4580 kg ha?1. Winter wheat did not vernalize during the first growing season but remained at the vegetative stage. The grain yield of wheat was 1990 kg ha?1 for the lowest and 5610 kg ha?1 for the highest seed rate of wheat. Whilst the undersowing process itself stimulated weed emergence in this experiment, increasing the undersowing seed rate reduced the population of perennial weeds by 40–70 %. In the second growing season, the total biomass of weeds was 66 % higher at the highest seed rate compared with the lowest seed rate.  相似文献   

19.
Most methods used to estimate N status require collection, processing and analysis of soil and/or plant tissue samples. In this study, leaf chlorophyll content of cereals, determined in the field with a portable chlorophyll meter (Minolta SPAD-502), was used to predict N availability of wheat ( Triticum aestivum L.), barley ( Hordeum vulgare L.), oats ( Avena sativa L.) and rye ( Secale cereale L.). The results indicated that accurate nitrogen (N) fertilizer recommendations based on chlorophyll content have both environmental and economic advantages. Determination of leaf chlorophyll content with a chlorophyll meter accurately indicated plant N status allowing N fertilizer requirement to be accurately determined and resulting in increased N uptake efficiency. Applying N fertilizer on this basis improved production economics and improved physical input-output ratio during grain yield formation. Using a chlorophyll meter, responsive and non-responsive categories can be determined at the stage of maximum number of florets per ear primordium (Zadoks' GS 37-41) and at pollination (i.e. pollen grains on well-developed stigmatic hairs, GS 52-58).  相似文献   

20.
气候及其变率变化对东北地区粮食生产的影响   总被引:21,自引:1,他引:20  
利用GISS、GFDL和UKMO 3种国际上通用的平衡大气环流模型(GCM)的有关输出值, 结合东北3大农业生态区19个样点近40年(1961—2000)的逐日气候资料(Baseline)以及未来气候变率变化(ΔCV)的3种假设, 并利用天气发生器(WGEN), 生成每个样点9种兼顾气候及其变率变化的(CC+ΔCV)情景; 选用DSSAT中的SOYGRO、CERES-Maize、CERES-Wheat和CERES-Rice作为效应模型, 并利用各样点的Baseline, 同期大豆、玉米、小麦和水稻的产量统计资料以及典型土壤资料, 对上述模型进行参数调试、可靠性检验和灵敏度分析; 将各效应模型分别在CC+ΔCV情景及Baseline下运行, 通过比较模拟结果, 就CO2有效倍增时气候及其变率变化对不同生态区粮食作物的影响做出定量评价。结果表明, 4种效应模型在研究区域均有较好的适应性, 其作为气候变化影响评价工具具有合理性; 气候变暖对东北大豆和水稻生产总体上有利, 尤其是在北部高寒区与东部湿润区, 模拟产量均明显提高, 但CC对玉米和小麦生产的影响以负面为主, 特别是玉米在各生态区不同情景下均表现为剧烈减产; 随着ΔCV增大, 雨育大豆、玉米和春小麦不仅模拟产量下降, 而且稳产性变差, 但对灌溉水稻影响不大。  相似文献   

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