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为了提高黔西北山区马铃薯的产量,以威芋 5 号马铃薯原种为试验材料,研究白色透明膜垄作、黑膜垄作覆土自动破膜、白膜半膜覆盖集雨、黑膜半膜覆盖集雨 4 种不同覆膜方式及露地栽培不覆膜对马铃薯的生育期、经济性状、产量及种植效益的影响。结果表明,覆盖地膜能有效缩短马铃薯的生育期,覆膜最高能缩短 16d;不同海拔地区覆膜方式也会影响马铃薯的产量,在海拔为 953m 的地区以白膜半膜覆盖集雨和白色透明膜垄作的覆膜方式马铃薯产量最高,分别达 2079.91kg/667m2、2078.54kg/667m2,较露地栽培不覆膜增产 25.17%、25.09%;海拔高度 1562m 的地区白色透明膜垄作的覆膜方式马铃薯产量最高,达 2286.12kg/667m2,较露地栽培不覆膜增产 28.99%。4 种不同覆膜方式均较露地栽培不覆膜纯收益增加。因此,推荐在黔西北山区中低海拔 950m 左右地区种植马铃薯采用白膜半膜覆盖集雨和白色透明膜垄作的覆膜方式,在海拔 1500m 以上地区采用白色透明膜垄作的覆膜方式。 相似文献
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播期对早熟马铃薯产量及经济效益的影响 总被引：3，自引：0，他引：3
在荔波县低海拔（350～500m）温热地区不同播期对早熟马铃薯费乌瑞它产量、经济效益的影响研究结果表明,不同播期显著影响早熟马铃薯的产量及经济效益,播期间产量差异达到极显著水平,以12月20-30日播种产量最高,产量在1914．8-2020．5kg／667m^2;播期间的产值差异达到极显著水平,以12月15～20日播种产值最高,产值为1930．41～2014．90元／667m^2。生产上以12月15～20日播种为宜,播种过早易受冻害而缺窝影响产量,推迟播种产量虽稍有增加但市场价较低从而影响其经济效益。 相似文献
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沟垄覆膜对连作马铃薯土壤酶活性、理化性状及产量的影响 总被引：2，自引：0，他引：2
以当地主栽品种“新大坪”为试验材料,采用大田定位试验,研究了平畦不覆膜(CK)、平畦覆膜(T1)、全膜垄播(T2)、全膜沟播(T3)、半膜垄播(T4)、半膜沟播(T5) 6 种栽培模式对连作马铃薯土壤酶活性、理化性状及产量的影响。结果表明,沟垄覆膜栽培可不同程度提高马铃薯连作田土壤过氧化氢酶、脲酶、碱性磷酸酶的活性,其中 T2 对 3 种酶活性的提高效果最为显著;沟垄覆膜可降低土壤 pH,从而改善马铃薯根际土壤的理化性状,且以 T2 对土壤化学性质的改善最为明显,沟垄覆膜可不同程度提高土壤电导率;此外,沟垄覆膜栽培还可以显著提高马铃薯块茎的产量,其中T2 增产幅度最高可达 75%。本研究以期为半干旱地区马铃薯连作障碍的克服及提高马铃薯产量提供理论依据。 相似文献
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地膜覆盖对粉用马铃薯生长发育及产量的影响 总被引：11，自引：3，他引：8
为了研究地膜覆盖对粉用马铃薯生长的影响,对宁夏西吉地区主栽的宁薯4号品种采用不同播期下地膜覆盖和未覆膜两种栽培措施进行对比试验。结果表明,覆膜能使马铃薯开花期提前,从而增加薯块的生长时间,5月上旬到7月中旬,保水效应和抗旱增产效果明显,覆膜比未覆膜增产47.8%~67.2%。对主栽的青薯168号采用不同时期覆膜和不同时期揭膜的栽培方式进行对比试验,结果表明在播种前覆膜可以优化土壤环境,在块茎增长时期以后揭膜可以提高马铃薯的覆膜效果,提高马铃薯产量,最高增产可达76.3%。因而,在马铃薯种植期间使用地膜覆盖并适时的覆膜揭膜,能有效提高粉用马铃薯的品质及商品性。 相似文献
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为筛选出不同海拔高度适宜推广应用的马铃薯品种,指导大面积生产,2015年开展了5个马铃薯品种不同海拔种植产量与经济性状分析试验。结果表明:宣薯5号、青薯9号、威芋3号、威芋5号等4个品种,在习水县不同海拔区均能正常成熟,生育期82-106d。同一品种在不同海拔高度种植,生育期随海拔高度的上升而呈逐渐延长趋势。在海拔560m(同民)、1040m(良村)、1350m(仙源)地区种植,产量均比本地白花洋芋(CK)显著增产,增幅在24.98%~31.20%之间。海拔560m时,威芋5号为最适宜品种;海拔1040m时,宣薯5号为最适宜品种;海拔1350m时,威芋3号、威芋5号为较适宜品种。单株结薯数最多的是宣薯5号达6.9个,单株薯重和商品薯率最高的均是青薯9号,分别为达0.32 kg、82.16%。综上所述,威芋5号、宣薯5号、威芋3号等3个品种均适宜习水县海拔560m~1350m左右地区大面积生产上推广应用。 相似文献
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不同脱毒马铃薯早熟品种秋种筛选初报 总被引：2，自引：0，他引：2
采用单因子随机区组设计,在黔东南中海拔（600m左右）地区进行脱毒马铃薯早熟品种的秋种品比试验,筛选适合秋种的脱毒马铃薯品种。试验表明：中薯3号植株生长、产量形成受秋季环境影响较小,产量显著高于费鸟瑞它等个品种,但其薯形畸形,商品性差。综合产量、抗性和商品性等因素,较适宜本地秋种推广种植的早熟品种为费乌瑞它。 相似文献
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Summary The action of the X locus in the tomato was explored by studying meiotic behavior, pollen germination, pollen tube growth, and fertilization capability. Normal meiosis was observed suggesting no x meiotic lethality. Percent germination showed much variation from test to test depending on size of population. X and x pollen from homozygous sources showed no differences in pollen tube growth capability or fertilization capability. Pollen from the F1 plant had a lower mean pollen tube length than either X and x pollen. Using F1 pollen in backcrosses to the recessive parent resulted in deviations from expected segregation ratios for characters linked to x.Michigan Agricultural Experiment Station Article No. 5374. 相似文献
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H. J. Toxopeus 《Euphytica》1957,6(2):106-110
Summary A study was made on the possible influence of extraR
3-genes on the resistance to the physiologic racep
3 (=(3)) ofPhythophthora infestans. The data allowed of the conclusion that such an influence could be small only, not exceeding small differences in the average degree of field resistance existing between the groups of simplex, duplex and triplex plants. 相似文献
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Variation in the ribosomal RNA units of the generaLens andCicer 总被引：2，自引：0，他引：2
Summary Investigation of the organization of the tandemly repeated 5S and 18–25S ribosomal RNA (rRNA) genes was carried out on members of the generaLens andCicer using restriction endonuclease digestion and Southern hybridization. The 5S rRNA unit (gene+spacer) inLens (0.38 to 0.50 kb) andCicer 0.50 to 0.44 kb) is the largest among the legumes. InL. nigricans andL. culinaris ssp.odemensis a second repeat size was detected. Restriction maps for the 18–25S units ofLens andCicer species were developed. The 18–25S rRNA unit varied from 8.3 to 9.8 kb inLens and 10.5 to 11.4 kb inCicer. The only detectable variability in theLens andCicer 18–25S rRNA unit was in the length of the intergenic spacer (IGS) region, except for a HindIII site in the IGS region ofL. nigricans ssp.nigricans and in allCicer species.Similarities in the size of both 5S and 18–25S rRNA units were noted betweenL. culinaris ssp.culinaris andL. culinaris ssp.orientalis, which supports previous evidence thatL. culinaris ssp.orientalis is the progenitor of the cultivated lentil. Differences in the arrangement of both 5S and 18–25S rRNA units were noted betweenL. nigricans ssp.nigricans andL. nigricans ssp.ervoides, indicating either divergent evolution of these subspecies or alternatively incorrect taxonomy.On the basis of the size of the 5S rRNA unit,C. bijugum, C. chorassanicum andC. echinospermum formed a group with a slightly smaller unit than the otherCicer species. Similarities in the length of both 5S and 18–25S rRNA units ofC. arietinum andC. reticulatum possibly confirmC. reticulatum as the progenitor ofC. arietinum. Cicer cuneatum has a smaller 18–25S rRNA unit than the otherCicer species as a result of a smaller intergenic spacer. 相似文献
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P. Spiegel-Roy 《Euphytica》1979,28(2):361-365
Summary Evidence that Shamouti orange is a periclinal chimera has been obtained as all nucellar seedlings from two Shamouti trees, yielded only Beledi type fruit. All nucellars from another Shamouti tree bore only Shamouti type fruit, thus indicating a homohistont condition in another tree source. 相似文献
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《Netherlands Journal of Sea Research》1990,25(1-2):291-299
A host-parasite model is proposed to describe the dynamics of the P. decipiens complex life-cycle. Four developmental stages are considered: the adult worm in the final host's stomach, the larval stages in the invertebrate and fish hosts, and the free-living egg-larval stage. The dynamics of each stage are described by an ordinary differential equation.The sensitivity of the model to some parameter values forms the basis for a discussion of its potential use in the assessment of future management and control strategies. This is illustrated by examples of observed infections in cod (Gadus morhua) from Scottish waters in the light of the recent increase in the Grey seal (Halichoerus grypus) populations of the Orkney and Farne Islands. 相似文献
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《European Journal of Agronomy》2000,12(1):37-54
APSIM Nwheat is a crop system simulation model, consisting of modules that incorporate aspects of soil water, nitrogen (N), crop residues, and crop growth and development. The model was applied to simulate above- and below-ground growth, grain yield, water and N uptake, and soil water and soil N of wheat crops in the Netherlands. Model outputs were compared with detailed measurements of field experiments from three locations with two different soil types. The experiments covered two seasons and a range of N-fertiliser applications. The overall APSIM Nwheat model simulations of soil mineral N, N uptake, shoot growth, phenology, kernels m−2, specific grain weight and grain N were acceptable. Grain yields (dry weight) and grain protein concentrations were well simulated with a root mean square deviation (RMSD) of 0.8 t ha−1 and 1.6 protein%, respectively. Additionally, the model simulations were compared with grain yields from a long-term winter wheat experiment with different N applications, two additional N experiments and regional grain yield records. The model reproduced the general effects of N treatments on yields. Simulations showed a good consistency with the higher yields of the long-term experiment, but overpredicted the lower yields. Simulations and earlier regional yields differed, but they showed uniformity for the last decade.In a simulation experiment, the APSIM Nwheat model was used with historical weather data to study the relationship between rate and timing of N fertiliser and grain yield, grain protein and soil residual N. A median grain yield of 4.5 t ha−1 was achieved without applying fertiliser, utilising mineral soil N from previous seasons, from mineralisation and N deposition. Application of N fertiliser in February to increase soil mineral N to 140 kg N ha−1 improved the median yield to 7.8 t ha−1 but had little effect on grain protein concentration with a range of 8–10%. Nitrogen applications at tillering and the beginning of stem elongation further increased grain yield and in particular grain protein, but did not affect soil residual N, except in a year with low rainfall during stem elongation. A late N application at flag leaf stage increased grain protein content by several per cent. This increase had only a small effect on grain yield and did not increase soil residual N with up to 40 kg N ha−1 applied, except when N uptake was limited by low rainfall in the period after the flag leaf stage. The economic and environmental optima in winter wheat were identified with up to 140 kg N ha−1 in February, 90 kg N ha−1 between tillering and beginning of stem elongation and 40 kg N ha−1 at flag leaf stage resulting in a median of 8.5 t ha−1 grain yield, 14.0% grain protein and 13 kg N ha−1 soil residual N after the harvest. The maximum simulated yield with maximum N input from two locations in the Netherlands was 9.9 t ha−1. 相似文献
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T. Visser 《Euphytica》1965,14(2):125-134
The following observations were made on the inheritance of the juvenile period (elapsing between seed germination and first flowering) of apple seedlings.
- 1.Highly significant correlations (0.52 and 0.78 at n=382 and 71) were found between the length of the juvenile period and the degree to which seedlings or progenies as a whole show juvenile symptoms. This relation may provide a basis for the early elimination of seedlings with a relatively long juvenile period (and which are possibly late-bearing). 相似文献
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H. Lamberts 《Euphytica》1955,4(2):97-106
Samenvatting Van de alcaloïdvrije stammen 8, 80 en 102 gevonden door Von Sengbusch, is het in hoofdzaak de eerste, welke gediend heeft om practijkrassen te verkrijgen. Door schrijver werden in het landras van Schouwen 19 alcaloïdvrije planten gevonden. Bij één dezer genotypen berust de alcaloïdvrijheid niet op een der genen welke in de stammen van Von Sengbusch voorkomen. Bij onderlinge kruising van de vier hier genoemde lijnen ontstaan bittere hybriden; een gedeelte van de nakomelingen is eneneens bitter.In nummer W.H. 20, afkomstig van wilde lupine uit Spanje, is resistentie tegen meeldauw (Erysiphe polygoni D.C.) gevonden. De resistentie wordt bepaald door één dominante erffactor, door schrijver aangeduid met Er.Bij het onderzoek naar het voorkomen van resistentie tegen verwelkingsziekte (Fusarium oxysporum lupini) werd een aantal genotypen, welke op een bepaald proefveld en ook bij kasproeven niet werd aangetast, op andere plaatsen ziek. Van de schimmel zijn thans drie physio's ontdekt. Er zijn lijnen gevonden welke resistent zijn tegen de drie physio's.Gebleken is verder dat de bodemtemperatuur van grote invloed is op de aantasting. Tot ± 20°C vertonen de resistente planten geen aantasting en bij kruising van resistente genotypen met vatbare, vindt men bij physio 1 in de F2 splitsingen, welke ongeveer de verhouding 3 resistent : 1 vatbaar vertonen. Bij hogere temperaturen neemt de aantasting toe en bij 27°C worden zowel de resistente als de vatbare volledig ziek. Op grond van de ervaringen in de afgelopen 5 jaren, op zeer uiteenlopende proefvelden, mag worden aangenomen, dat in een goed ontwikkeld lupinegewas de bodemtemperatuur, althans in Nederland, niet of slechts kortere tijd, boven de gevaarlijke temperatuursgrens uitkomt. De gevonden resistentie is daarom van grote waarde voor de teelt.Bij de mozaïekziekte is resistentie gevonden in één lijn uit het Nederlandse landras. Deze resistentie is hierdoor gekenmerkt, dat in tegenstelling tot de vatbare planten, de ziekte eerst optreedt tijdens of na de bloei. Door deze late aantasting is de schade aan de opbrengst geringer dan normaal, terwijl tot dusverre geen overgang met het zaad werd aangetroffen.Uit een Palestijnse wilde herkomst is een nieuw type met een snelle jeugdontwikkeling geïsoleerd. De gunstige eigenschap berust op één dominante erffactor, (door schrijver Rapidus, Rp, genoemd) in tegenstelling tot het Duitse ras Weiko III, waar één recessief gen de snelle ontwikkeling bepaalt. Combinatie van beide genen geeft transgressie in de lengtegroei.Bij het niet openspringen van de peulen, het niet hardschalig worden van de zaadhuid en het onbehaard zijn van de peulen werden nieuwe genotypen ontdekt, welke ten dele als een vooruitgang ten opzichte van de reeds bekende mogen worden beschouwd.In Portugees wild materiaal werden enkele zeer goede zaadproducenten opgemerkt.Vermeld is welke landbouwkundige betekenis kan worden toegekend aan de verschillende behandelde eigenschappen. Tevens wordt besproken hoe de combinatie van de verschillende gunstige eigenschappen te verwezenlijken is.De bronnen, waaruit voor de veredeling kan worden geput, zijn: gekweekte rassen, landrassen en wilde vormen. Aangetoond wordt dat de wilde herkomsten de beste kansen voor verdere vooruitgang bieden. Er wordt op gewezen dat het noodzakelijk is op korte termijn zo veel mogelijk wild materiaal te verzamelen en maatregelen te nemen om de landrassen in stand te houden. Aanbevolen wordt dit internationaal te organiseren, zodat de verschillende landen de beschikking kunnen krijgen over een zo groot mogelijk aantal geniteurs. 相似文献
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S. J. Wellensiek 《Euphytica》1962,11(1):5-10
Shortening the breeding-cycle is a reduction of the time which is needed for growing one generation from seed to seed. The physiological processes involved in shortening the breeding-cycles in five different groups of plants are briefly discussed, and summarized in the scheme on p. 9.
Publication 218, Laboratorium voor Tuinbouwplantenteelt Landbouwhogeschool, Wageningen, Netherlands
Lecture in the section Physiology of Eucarpia, Gembloux, Belgium, 4th July 1961. 相似文献
Publication 218, Laboratorium voor Tuinbouwplantenteelt Landbouwhogeschool, Wageningen, Netherlands
Lecture in the section Physiology of Eucarpia, Gembloux, Belgium, 4th July 1961. 相似文献