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1.
根据多年研究结果和有关研究资料，对超高产栽培条件下的小麦产量因素结构及其土壤养分状况背景值进行了研究分析。认为产量因素结构大穗少穗型，多穗较多穗型和中穗多穗型分别为４００万穗／ｈｍ＾２，４５粒／穗，５０ｇ／１０００粒，５００万穗／ｈｍ６２，３８粒／穗，４８ｇ／１０００粒；６００万穗／ｈｍ＾２，３０粒／穗，４０ｇ／１０００粒。 相似文献
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皇草高产配套栽培技术研究 总被引：11，自引：0，他引：11
本试验用田间试验和定量分析的方法研究皇草高产与主要栽培因子之间的数量关系,建立了有关数学模型并作了增产效应分析。在试验条件下,皇草产量要达到２１６３４５ｋｇ／ｈｍ＾２,种植密度应为３９７２４窝／ｈｍ＾２,配施纯Ｎ为５７２．２５ｋｇ／ｈｍ＾２,Ｋ为１８７．７５ｋｇ／ｈｍ＾２,Ｐ为２６９．４８ｋｇ／ｈｍ＾２,达到皇草高产目的。 相似文献
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川中丘区“麦／玉／苕”模式玉米高产综合栽培技术研究 总被引：3，自引：1，他引：2
运用三因素五水平二次正交旋转组合试验设计方法，研究了川中丘区“麦／玉／苕”模式玉米的播种期，栽植密度和氮化肥用量对产量及其主要经济性状的影响，建立了相应的数学模型，得出郑单１４在育苗移栽，地膜栽培条件下产量６．７５ｔ／ｈｍ＾２以上的高产栽培技术方案的：播种期３月５－１５日，栽植密度６．４－７．０株／ｍ＾２，氮化肥用量２２０－２７０ｋｇ／ｈｍ＾２。 相似文献
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麦棉两熟平衡施肥效应研究 总被引：5，自引：0，他引：5
１９９２～１９９３年在淮北平原黄泛冲积潮砂壤中等偏下地力进行了麦棉两熟平衡施肥试验。结果表明，麦棉作物对施肥的反应敏感，棉花施用有机肥增产最显著。施肥可增加小麦单位面积有效穗数和每穗粒数，棉花可增加单株成铃数和铃重，但秋桃比例提高，熟性推迟。首次提出麦棉两熟高投入高产出高效益的平衡施肥方案，周年全田最佳小麦产量３７５０ｋｇ／ｈｍ２，棉花最佳产量１３５０ｋｇ／ｈｍ２，总化肥养分施用量７９５ｋｇ／ｈｍ２，麦棉季各半，Ｎ：Ｐ２Ｏ５：Ｋ２Ｏ为１：０．５：０．５。即小麦棉花各施Ｎ１８７．５、Ｐ２Ｏ５９０～９３．８和Ｋ２Ｏ９０～９３．８ｋｇ／ｈｍ２，棉花季施用硼砂１５ｋｇ／ｈｍ２，硫酸锌３０ｋｇ／ｈｍ２。提倡重施基肥，早施追肥。 相似文献
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冬小麦新品种冀麦38 总被引：1，自引：0，他引：1
冀麦３８是河北省石家庄市农科院以多穗抗病品种植４００１为母本，以石４２１２－１０为父本，１９８３年杂交，连续８年单株选择而成。１９９７年秋播８０万ｈｍ２，平均产量７５００～９０００ｋｇ／ｈｍ２。１９９６年经河北省农作物品种审定委员会审定。现已成为河北... 相似文献
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采用４因素二次饱和Ｄ－最优设计,通过微机模拟计算,建立了大豆产量与大豆专用肥中氮、磷、钾、褐煤等主要成分用量的数学模型。对参试因素及其产量进行了较系统的分析,获得了最高产量施肥量;筛选出大豆产量１２００￣１８００ｋｇ／ｈｍ＾２时,以１５０ｋｇ／ｈｍ＾２为间距的５组专用肥主要成分优化组合方案;当大豆产量≥１８００ｋｇ／ｈｍ＾２时,专用肥中主要成分最佳用量为：氮肥（Ｎ）３８．９５￣８８．２３ｋｇ／ｈｍ 相似文献
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河南小麦超高产育种与品质利用途径 总被引：1，自引：0，他引：1
河南地处南北过渡的中原生态类型区,小麦超高产育种应选择半冬性或弱春性、多穗兼大穗、中等粒重类型的品种,走稳穗增粒的道路。产量指标为８２５０ｋｇ／ｈｍ＾２,且有９７５０ｋｇ／ｈｍ＾２的增产潜力。品质的改良要在政府的组织协调下多部门配合,使现有的优质品种得到充分利用,促进品质育种、品质栽培等研究工作的发展。 相似文献
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Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts 总被引：7，自引：0，他引：7
Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed. 相似文献
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C. J. Spurr D. A. Fulton P. H. Brown R. J. Clark 《Journal of Agronomy and Crop Science》2002,188(4):275-280
Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality. 相似文献
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Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans. 相似文献
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Hongyan WEI Jian ZHOU Jinguang LU Jingzheng SONG Qiongxi YU Zhihong JIANG 《Medicinal Plant》2019,(6):27-29
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol... 相似文献
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Chunli TANG Fengxian ZHAO Hongxia CHEN Jiabao MA Jiangcun WEI Meiyan QIU Zhen XIE 《Medicinal Plant》2019,(6):60-65
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination... 相似文献
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D. A. Bond G. J. Jellis G. G. Rowland J. Le Guen L. D. Robertson S. A. Khalil L. Li-Juan 《Euphytica》1993,73(1-2):151-166
Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses. 相似文献
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Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed. 相似文献
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[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho... 相似文献
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E. Keep 《Euphytica》1986,35(3):843-855
Summary Cytoplasmic male sterility (cms) is described in the F1 hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf
1) and recessive for the other (Rf
2).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph
3(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf
1(one of two dominant additive genes controlling early season leafing out) indicated that Rf
1and Rf
2were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf
1, and 0.15 for Lf
1-Sph
3were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph
3.It is suggested that competitive disadvantage of lf
1-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph
3. Poor performance of lf
1- (and possibly lf
2-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off). 相似文献
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Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques. 相似文献