秸秆还田条件下玉米-高粱（玉米）-大豆轮作的产量与效益分析

为明确不同轮作模式的籽粒产量与经济效益差异,推广合理的轮作种植模式,试验设置玉米-高梁-大豆、玉米-玉米-大豆、连作玉米、连作大豆4种种植模式。研究结果表明:玉米-高梁-大豆、玉米-玉米-大豆中大豆籽粒产量较连作大豆籽粒产量分别增加23.88%和17.55%,玉米-高梁-大豆和玉米-玉米-大豆轮作模式年净收益比连作玉米分别高1377元/hm^2和336元/hm^2,玉米-高梁-大豆和玉米-玉米-大豆轮作模式年净收益比连作大豆分别高2279元/hm^2和1237元/hm^2,玉米-高梁-大豆轮作年净收益比玉米-玉米-大豆轮作高1041元/hm^2。     

全国麻类作物学术讨论会在余杭召开

中国是世界上麻类作物种类最多的国家,栽培有苧麻,黄麻、红麻、亚麻、大麻、青麻、龙舌兰麻等,年总产量曾达到4000多万担。麻纤维吸水、散热快,拉力较强。不同种类麻的纤维因细度和拉力不同,分别可织成绳索、包装袋(布)、高挡织物衣料等各种麻织品。在国际市场上,中国苧麻织物供不应求;亚麻织品销路很好;黄、红麻产品竞争能力也很大。因此,加强我国麻类作物生产、纺织加工和科学研究工作,对发展经济,促进内销外贸,改善人民衣着都有很大作用。     

杂交红麻简化栽培的探讨

红麻杂种优势利用研究已进行多年,在生产上起了很大的作用。中国农科院麻类研究所选配的“红优5号”杂交种在各地种植结果表明,具有生长势强,经济性状好,单株生产力高等杂种优势,增产效果明显,深受麻农的欢迎。然而,由于杂交制种成本较高,制种量少,影响大面积种植和推广。为此,我们根据杂交麻的增产潜力,进行了稀植、少播、撒播简化栽培试验和研究,探讨杂交红麻的经济价值,为杂交红麻在生产上大面积应用提供依据。现将近年来的研究结果报导如下:     

专题导读:加强麻类作物基因组学研究,推动优异等位基因发掘及种质创新

麻类作物是指以收获茎秆韧皮纤维和叶纤维为主的作物,主要包括黄麻(Corchorus spp.)、红麻(Hibiscus cannabinus)、苎麻(Boehmeria spp.)、亚麻(Linum usitatissimum)、工业大麻(Cannabis sativa L.)与剑麻(Agave sisalana Perr.ex Engelm.),与粮、棉、油、菜并列为第五大作物群[1],其种植历史可追溯到远古新石器至尧舜时代。我国是麻类生产大国。2009年,作为50个农产品之一的麻产品被列入国家现代农业产业技术体系。2011—2020,以二代、三代测序技术为主体,以Hi-C等技术辅助,先后完成了主要麻类作物染色体级别的草图或参考基因组,这标志着麻类作物科学已经进入基因组时代。为加强主要麻类作物基因组学与遗传改良研究,《作物学报》以专栏形式集中刊发了8篇论文,方便相关研究工作者了解最新研究动态。     

川西高原马铃薯/玉米/大白菜套作研究

试验对川西高原半高山地区马铃薯/玉米/大白菜套作、马铃薯-玉米套作、小麦-玉米套作3种套作模式的产量和经济效益进行比较分析.结果表明：实行马铃薯-玉米-大白菜套作种植总产量、总产值、净收益均极显著高于其它两种套作模式.     

胶东地区典型种植模式效益比较研究

摘要 对胶东地区现有的粮-菜、菜-菜、粮-粮、粮-果四大主要种植类型中的7种典型种植模式的经济效益进行了比较研究。结果表明：7种种植模式中菜-菜种植模式效益最高,粮-菜类型、粮-果类型效益次之,粮-粮类型效益最低。从产投比看,粮-粮类型的产投比最小,其余类型的产投比都在1.44以上。在此基础上探讨影响莱阳种植结构变化的主要原因以及存在的问题,提出种植业的发展建议。     

吊瓶精准输液技术对芒果产量的影响

采用吊瓶精准输液技术,在芒果树开花到成熟期按树体大小定量向树杆木质部注射营养液,以确定对芒果产量的增产效应,结果表明：芒果果数可增产23.85%,单果重可增产22.77%,总产量可增产52.06%,其产投比为3.38:1,是对照产投比（2.29:1）的1.48倍。通过定量分析和计算机模拟的方法推导出芒果精确施肥用药量的数学模型为?=5.15383(D)3.09674(g),对吊瓶输液技术导致芒果抗旱丰产的原因进行分析及讨论。     

施用磷和钙对花生生长、产量及磷钙利用效率的影响

发挥元素间互作优势是作物高产及养分高效利用的重要措施。为探明外源磷钙配施在花生上的作用效果及磷钙互作关系,在豫南砂姜黑土区开展了施用磷钙对花生生长、产量及磷钙吸收利用的影响研究。结果表明,单独施磷和磷钙配施比不施磷钙肥显著促进了花生生长和增产;磷钙配施比单独施磷显著增产29.75%,主要原因是增加了花生单株饱果数、单株饱果重、百果重和出仁率,且磷钙配施比单独施磷显著增加花生体内磷积累量、磷吸收和利用效率,其中磷吸收和利用效率分别增加5.36%和8.08kg/kg;单独施磷比不施磷钙显著增加花生体内钙积累量、吸收和利用效率,其中钙吸收和利用效率分别增加1.72%和3.60kg/kg,表明磷钙之间存在协同效应。因此,磷钙合理配施可提高花生磷钙吸收效率,有利于花生生长和增产,是花生高产及磷钙高效利用的一种优化施肥模式。     

双季糯高粱间作大豆田间配置方式优化

为了减轻双季糯高粱连作障碍,优化双季糯高粱、大豆田间配置结构,提高两季作物产量效益,以常规双季糯高粱‘国窖红1 号’、‘南豆12’为试验材料,研究不同田间配置方式对糯高粱、大豆复合种植、净作模式下产量、效益的影响。结果表明：复种模式下作物总产量、总产值均高于双季糯高粱、大豆净作模式,头季糯高粱产量、千粒重、穗粒重和穗长随厢宽的增加而降低,再生季糯高粱、大豆表现为先增后减的趋势;双季糯高粱总产量最高的为1.7 m开厢处理,达8352.9 kg/hm2,大豆产量最高为1.8 m开厢处理,达1888.95 kg/hm2,两作物总产值、净收益以1.7 m 开厢处理最高,分别为47293.92 kg/hm2、29976.42 kg/hm2,其次为1.8 m开厢处理,以上两处理为最优田间配置方式。产投比以净作双季糯高粱最大,净作大豆最低。     

塑料大棚内麻地膜覆盖草莓效应的初步研究

为明确麻地膜在大棚内覆盖栽培对作物的影响特点,在大棚和露地同时进行不同地膜覆盖草莓的比较试验。结果表明：麻地膜在大棚内覆盖的增温、保水效应比在露地大,能够提早草莓开花结果,显著提高产量。大棚和露地不同种植环境与不同覆盖处理间的互作效应极显著。麻地膜在大棚内的增产效果更好,比无覆盖增产12.8%,比塑料地膜增产1.73%。麻地膜比无覆盖在大棚内的增产幅度要比在露地多增产4.3%。     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

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.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

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.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

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.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

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.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

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.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

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).     

Screening techniques and sources of resistance to parasitic angiosperms

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.