苎麻茎皮cDNA文库的构建

以生长中期的苎麻茎皮为材料，提取总RNA，经纯化mRNA后，合成双链cDNA。双链cDNA加上EcoRI—SmaI接头后，用限制酶NotI酶切并除去小于400bp的短链cDNA，长的cDNA片段连接到EcoRI—NotI酶切载体pAP3neo上，获得滴度为2．6×10^4的苎麻cDNA文库，插入片段大部分分布在500bp-1500bp之间。该文库的建立为苎麻表皮功能性新基因的发现奠定了基础。     

苎麻茎皮cDNA文库的构建

以生长中期的苎麻茎皮为材料,提取总RNA,经纯化mRNA后,合成双链cDNA。双链cDNA加上EcoRI-SmaI接头后,用限制酶NotI酶切并除去小于400bp的短链cDNA,长的cDNA片段连接到EcoRI-NotI酶切载体pAP3neo上,获得滴度为2.6×104的苎麻cDNA文库,插入片段大部分分布在500bp～1500bp之间。该文库的建立为苎麻表皮功能性新基因的发现奠定了基础。     

苎麻组织培养及遗传转化研究进展

概述了国内外苎麻组织培养的快速繁殖、器官发生、体细胞胚胎发生、原生质体培养、花药培养等几个方面以及遗传转化的研究进展,并对存在的问题和前景进行了讨论。     

苎麻组织培养及遗传转化研究进展

概述了国内外苎麻组织培养的快速繁殖、器官发生、体细胞胚胎发生、原生质体培养、花药培养等几个方面以及遗传转化的研究进展，并对存在的问题和前景进行了讨论。     

两种乙烯抑制剂对苎麻(Boehmeria nivea(L.) Gaud)性别及植物学性状的影响

用AVG和AgNO3诱导苎麻以控制其花的性别表现。用不同处理浓度AVG(300、100mg/L)、AgNO3(100、300、500m g/L),在苎麻生长到15节时开始处理,观察统计雌花、雄花形成的数量并进行统计分析,找出最佳处理水平。结果表明,乙烯抑制剂可以控制苎麻的性别表现。AVG300mg/L、AgNO3300mg/L为最佳诱导剂浓度。     

两种乙烯抑制剂对苎麻(Boehmeria nivea(L.)Gaud)性别及植物学性状的影响

用AVG和AgNO3诱导苎麻以控制其花的性别表现。用不同处理浓度AVG（300、100mg／L）、AgNO3（100、300、500mg／L），在苎麻生长到15节时开始处理，观察统计雌花、雄花形成的数量并进行统计分析，找出最佳处理水平。结果表明，乙烯抑制剂可以控制苎麻的性别表现。AVG300mg／L、AgNO3300mg／L为最佳诱导剂浓度。     

Ramie (Boehmeria nivea (L.) Gaud.) and Spanish Broom (Spartium junceum L.) fibres for composite materials: agronomical aspects,morphology and mechanical properties

The agronomic characteristics of Ramie and Spanish Broom were investigated for seven years in the pedoclimatic conditions of Central Italy. The chemical, physical and mechanical properties of these fibres were also examined in order to evaluate the feasibility to use them in composite materials. Results demonstrate that Ramie grown in the temperate environment can be harvested three times a year. The yield of green Ramie plants per annum was almost 10 000 g m⁻². The fresh Ramie plant is composed, by weight, of 30% green leaves and 70% green stems. The yield dry fibre is almost 3% of the green stems, giving a total yield of 200 g m⁻². Spanish Broom can reach a fresh biomass yield of 4000 g m⁻² per annum, represented by 53% of long slender terete green branches which constitutes the economic products. The dry yield per annum was about 1800 g m⁻² with a dry branchlets yield of 900 g m⁻². Ramie and Spanish Broom cortical fibres are multiple elementary fibres (ultimates) arranged in bundles. In Ramie, the elementary fibres are bound by gums and pectins, while in Spanish Broom they are bound together by lignin. Both species showed a thick secondary cell wall indicating a high cellulose content. Ramie ultimate fibres are flattened and irregular in shape, while those of Spanish Broom are more regular in shape. The diameter of the ultimates varies from 10 to 25 μm in Ramie, while the Spanish Broom ultimates ranges from 5 to 10 μm; the diameter of the whole bundle is about 50 μm for both species. Ramie fibre showed a content of lignin, pentosans and extractives lower than Spanish Broom. Both fibres had a high content of cellulose which, on the base of X-ray analysis, was evaluated to be in excess of 70%. Ramie and Spanish Broom fibres had tensile strength of 950 MPa and 700 MPa, respectively. The elastic moduli were ≈65 and ≈20 GPa, respectively, which well compare with the modulus of E-glass fibres (70–90 GPa). The strength of the fibre-matrix interface was measured using the single filament fragmentation technique and an epoxy resin as the polymer matrix. Values for carbon and glass fibres in the same resin were also measured for comparison. The interface strength for the vegetable fibres was higher than that of carbon and glass, likely due to a mechanical lock mechanism. These values confirm both fibres as potential replacement for man made fibres in composite materials.     

Effects of growth regulators on the growth and yield of detached and transplanted potato (Solanum tuberosum L.) sprouts

Summary Roots of 15-day-old sprouts detached from tubers of potato (Solanum tuberosum L.) cv., Local Red, were dipped for 1 min in a 0.25% solution of Ethrel (ethephon), Rootone-F (RF), or Transplantone (TP) or in water and then planted in the field. Plants treated with RF and TP were significantly (P<0.05) taller, had heavier haulm, produced more leaves, and yielded more tubers than those of the control treatment with water, ethephon had no effect. RF was significantly (P<0.05) superior to TP for all measured components except leaf number.     

Fiber yield and quality of fiber nettle (Urtica dioica L.) cultivated in Italy

To evaluate the production potential of fiber nettle crops in Tuscany (Italy), a German clone of fiber nettle was cultivated during 2006–2007.Although a longer experimentation is essential, the two first years of trials showed that the German clone used also seems to give good results in term of growth and fiber yield in an environment like central Italy, with higher temperatures and generally lower rainfall. Indeed the stalk mean dry matter obtained was about 15.4 Mg ha^?1 with a mean fiber content of about 11% of stalk dry matter, and the resulting fiber yield was 1696 kg ha^?1, comparable to or higher than those reported in the literature.The differences in chemical, physical and mechanical characteristics of fibers extracted from different portions of stalks seemed to indicate an intrinsic heterogeneity of the fibers along the stem. Fiber mean diameter values ranged from 47 to 19 μm and fiber length from 43 to 58 mm moving from stalk bottom to top. Tensile strength of the bottom part of the stalk was much lower than that of the other parts, with mean values of about 24 and 60 cN tex^?1, respectively. More constant mean values along the stalk were found for the elongation parameter (2.3–2.6%). Lignin content decreased moving toward the stalk top from about 4.4% to 3.5%.These physical–mechanical characteristics confirmed the potential of the fibers of nettle cultivated in Tuscany to be used for textile purposes. Indeed they were similar to hemp fibers in diameter, lignin content and elongation, and similar to flax or cotton in tensile strength.     

Effect of two plant growth regulators on the yield and quality of russet burbank potatoes

Summary Foliar applications of ethephon (ETH) 300 g a.i. ha⁻¹; chlormequat chloride (CCC) 920 g a.i. ha⁻¹, with a second application of 230 g a.i. ha⁻¹ approximately 2 weeks later; and a mixture of the two (ETH/CCC) 156 g a.i. ethephon and 299 g a.i. chlormequat chloride ha⁻¹ were made to field-grown Russet Burbank potatoes in 1986, 1987 and 1989. All the treatments increased the number of tubers set and reduced the average tuber weight compared to the control resulting in a reduction in premium and marketable tubers, and an increase in small tubers. Differences were greatest for ETH and least for CCC. ETH and ETH/CCC decreased the specific gravity, increased the incidence of deformities, and decreased the incidence of tubers with hollow heart. The growth regulators did not affect fry colour.     

光周期钝感全雌性苎麻特征特性的初步鉴定

1985年以来,发现了4个亲缘系统的光钝感全雌性苎麻(简称NG苎麻)材料,若不砍杆,在荆州每个生长季节可开3或4期花。栽后第一年,所有NG株系仅开雌花,但两年后有的年份第一花期有极少雄花。第一花期后,如不割杆,新梢上只生雌花;若于6—8月砍杆,则表现雌雄同株。NG型苎麻植株较矮,韧皮层较薄,鲜皮出麻率较低,但纤维极细。认为,该材料在苎麻育种中有重大的实用价值,也是研究光期反应、开花及性型的遗传与表达的良好材料。     

苎麻化学调控研究进展

综述了植物生长调节剂对苎麻生长发育的影响.苎麻生长发育的化学调控受不同生长调节剂的作用,不同生长调节剂对苎麻的生长发育表现出不同的生理效应,具体表现为对苎麻生长发育的促进作用、抑制作用及协调作用.并提出了今后发展植物生长调节剂的主要途径以及化学调控在苎麻生长发育上的乐观前景.     

苎麻化学调控研究进展

综述了植物生长调节剂对苎麻生长发育的影响。苎麻生长发育的化学调控受不同生长调节剂的作用，不同生长调节剂对苎麻的生长发育表现出不同的生理效应，具体表现为对苎麻生长发育的促进作用、抑制作用及协调作用。并提出了今后发展植物生长调节剂的主要途径以及化学调控在苎麻生长发育上的乐观前景。     

Effect of defoliation frequency and cutting height on growth,dry‐matter yield and nutritive value of Napier grass (Pennisetum purpureum (L.) Schumach)

Growth characteristics, dry‐matter (DM) yield, chemical components and in vitro dry‐matter digestibility (IVDMD) of Napier grass were studied in a randomized complete block design with three replications at Haramaya University, Ethiopia. The treatments were three defoliation frequencies (60, 90 and 120 d after Napier grass establishment) and five cutting heights (5, 10, 15, 20 and 25 cm above ground level). Except for leaf‐to‐stem ratio, all growth characteristics increased with decreasing frequency of defoliation. Similarly, DM yield of Napier grass increased as the frequency of defoliation decreased. Total ash, crude protein (CP), hemicellulose and IVDMD contents of Napier grass increased with increasing frequency of defoliation, whereas DM, acid detergent fibre, acid detergent lignin and cellulose contents increased with a decrease in defoliation frequency. In contrast, cutting heights had no significant effect on most chemical components and IVDMD contents, although total ash and CP decreased as the height of cutting increased. The CP yield per cut and per day was highest at an intermediate defoliation frequency. The results of this study indicated that Napier grass could be categorized under medium‐ to high‐quality herbage if defoliated at 90 d after establishment in the mid and highlands of Ethiopia.     

生长调节物质对花生叶片衰老调控的初步研究

结荚期喷施０．０１ｍＭ赤霉素,０．０５ｍＭＮ＾６－苄基腺嘌（６－ＢＡ）,５ｍＡ脯氨酸,３ｍＭ抗坏血酸,１０ｍＭ甘氨酸,６ｍＭ乙烯利等生长调节物质均可提高花生叶片叶绿素含量和净光合速度,增加叶片可溶性蛋白持含量,降低叶片内丙二醛积累量,提高叶片超氧化物歧化酶,过氧化物酶和过氧化氢酶活性,延缓花生叶片衰老,提高产量。     

Effect of different levels of nitrogen and farmyard manure on yield and quality of spinach (Spinacea oleracea L.)

The effect of different levels of nitrogen N₀(0kg/ha), N₁(30 kg/ha), N₂ (60 kg/ha), and N₃ (90 kg/ha) and farmyard manure F₀ (0 tonnes/ha), F₁ (10 tonnes/ha), and F₂ (20 tonnes/ha) on the yield and nutrient composition of spinach and its uptake was investigated on a sandy loam soil. Yield; phosphorus, iron, manganese, zinc, and copper uptakes; and ascorbic acid content increased with the application of both the inorganic nitrogen fertilizer and the farmyard manure, with a maximum at the N₃F₂ level, i.e. at 90 kg N/ha with 20 tonnes FYM/ha. However, the contents of protein, -carotene, and reducing sugars were maximum at the highest dose of nitrogen without the application of farmyard manure.     

Effect of sowing date on the growth and seed yield of common bean (Phaseolus vulgaris L.) in highland environments

Evaluations of common bean cultivars in the highlands of Mexico indicated that land races from that region experience less reduction in seed yield and seed size in late sowings than do lines from other regions. Introduced materials are of interest as sources of increased disease and pest resistance and tolerance to edaphic constraints, however. To quantify effects of sowing date and determine possible underlying causes, germplasm of diverse origins was evaluated at two sites in the highlands using multiple sowing dates. In all trials, seed yield, seed weight, harvest index and canopy dry weight decreased with late sowings. Large effects of sowing date, cultivar and their interaction were found for the four traits. The possible importance of phenology per se and of weather conditions was first examined using regression analyses. Variation in seed yield, seed weight, harvest index and canopy dry weight was more closely associated with time to maturity than with time to flowering. Of three weather variables examined, minimum temperature during seed filling revealed the strongest relations with the four traits. Few interactions of any parameter with line were significant, indicating that the cultivars did not have a strong differential response to a specific weather condition such as night temperature. Simulation analyses comparing photoperiod-sensitive and day-neutral cultivars indicated that radiation and temperature explained part of the yield reduction with late sowings. Daylength also had an influence, however, even in the day-neutral cultivar. Given that phenology had a strong effect on yield and that its inheritance is better understood than that of other physiological traits, priority should be given to understanding the genetic basis of the response of cultivar phenology to sowing date in the region.     

Effect of herbicides and annual weeds on the yield and seed quality of lathyrus (Lathyrus sativus L.)

Field research conducted over six location years has indicated that lathyrus (Lathyrus sativus L.) is a poor competitor with annual weed species. Failure to control annual weeds reduced lathyrus seed yields by 54–95%, depending on the weed species present and their density. Weed competition also reduced thousand-seed weight. Preplant soil-incorporated applications of trifluralin and postemergence applications of sethoxydim controlled wild oat (Avena fatua L.) and green foxtail (Setaria viridis (L.) Beav.). Trifluralin failed to control wild mustard (Sinapis arvensis L.), an important broad-leaved weed in western Canada, but this weed was controlled by both preplant soil-incorporated and postemergence applications of metribuzin. Lathyrus exhibited excellent tolerance to these herbicides, which are currently registered for use on high-acreage crops in Canada.     

绿肥压青改土对秋植蔗高产群体产量和品质的效应初报

本试验在大田生产条件下,通过选用花生、大豆、绿豆三种绿肥进行压青改土,研究改土后对秋植蔗产量和品质的效应,其结果表明:三种豆科作物压青均能起到增产增糖的效果,其中以大豆压青效果最好,其次是绿豆,花生是收获荚果后压青,效果最差,说明绿肥养地在大田生产上是有效可行的,对广西甘蔗的生长必将产生深远的影响.     

Effect of irrigation schedule on growth and seed yield of camelina (Camelina sativa L.) in Tarai region of central Himalaya

Camelina(Camelina sativa)has emerged as a potential biofuel crop globally with its suitability even as a jet fuel source with 75–80%less greenhouse gas emissions compared to common petroleum fuels.The crop has originated from Mediterranean region and belongs to Brassicaceae family.DIBER,DRDO has made initial and pioneer efforts in successful introduction of this crop to India and its agro-technology standardization.Being a short duration crop with lesser input requirement,it fits well in the cropping pattern of hilly states of Indian Himalaya.These areas experience fallow land due to shortage of irrigation water for growing other crops.The present study revealed that irrigation at flowering stage is more beneficial.Irrigation at this stage(if only one irrigation is available)exhibited grain yield of 1.004 kg·m^-2which was 21 and 80%higher over pod setting and rosette stage irrigation,respectively.The maximum seed yield was observed under treatment where irrigation was provided at all three crop growth stages(2.044 kg·m^-2).It was 50%higher over T6 treatment(where two irrigations were given at rosette and flowering stage)and 104%higher over T3(where only one irrigation was given at flowering stage).