AgNO_3对苹果叶片培养的影响及其与乙烯产生的关系

在附加６－ＢＡ３．０ｍｇ／Ｌ，ＩＢＡ０．０５ｍｇ／Ｌ的ＭＳ再生培养基中加入１￣１００μｍｏｌ／Ｌ ＡｇＮＯ３，均显促进苹果叶片再生不定芽，但以１μｍｏｌ／Ｌ浓度效果最好，与对照相比，在培养早期，１μｍｏｌ／Ｌ ＡｇＮＯ３对乙烯的抑制率为１６％￣２０％，在培养中后期则为２５％￣４０％，因而显降低了各培养时期，特别是中后培养容器中乙烯的浓度，降低了乙烯对芽发生的抑制，从而促进不定芽的发生。     

草莓主栽品种Tudla遗传转化体系的建立

本研究建立起农杆菌介导的草莓主栽品种Ｔｕｄｌａ的转化体系,获得了转化植株,试管苗叶片与携双元载体ｐＭＯＧ４１０的农杆菌菌株ＥＨＡ１０５共培养３天,共培养后叶片在附加止那霉素４０ｍｇ．Ｌ＾－１的再生培养基（ＭＳ＋ＴＤＺ２．０ｍｇ．Ｌ＾－１＋ＩＢＡ０．１ｍｇ．Ｌ＾－１）上选择培养４周后,外植株再生出明显可见的转化芽,转化芽再生频率达４．５％,转化芽在附加卡那霉素２５ｍｇ．Ｌ＾－１草莓继代培养基上分化成     

药用植物甜茶的快速繁殖

将甜茶（ＲｕｂｕｓｓｕａｖｉｓｉｍｕｓＳ．Ｌｅｅ）茎段接种在以ＭＳ和Ｗｈｉｔｅ为基本培养基分别附加不同浓度ＢＡ的培养基上。研究表明,以ＭＳ为基本培养基附加２ｍｇ／Ｌ的ＢＡ和０．５ｍｇ／Ｌ的ＮＡＡ,对芽的增殖和生长效果较显著,增殖率比对照高９１％。将试管苗转入以ＭＳ为基本培养基附加１ｍｇ／Ｌ的ＮＡＡ和２ｍｇ／Ｌ多效唑的培养基中,出根率最高达４３％,根茎粗壮。     

添加硅、硼元素对甘蔗组培苗生长的影响

以“新台糖１６号”甘蔗品种试管苗为材料,采用液体培养方法,以ＭＳ为基本培养基,附加激素ＢＡ ３ｍｇ／Ｌ、ＮＡＡ０．５ｍｇ／Ｌ,ＮａＳｉＯ３２００ｍｇ／Ｌ,苗增殖率比对照提高６８％,叶色浓绿、叶片挺直、硬、不早衰。比对照延长生长期２３ｄ。生根阶段,以ＭＳ为基本培养基,附加ＮＡＡ１ｍｇ／Ｌ、硼酸３０ｍｇ／Ｌ,生根数比对照增加５３％,根长、苗壮。     

树胡椒的组织培养

树胡椒种子作为外殖体进行微繁殖,不同培养阶段适宜的培养基分别为：（１）愈伤组织诱导：ＭＳ＋ＢＡ１ｍｇ／Ｌ＋ＮＡＡ０．１ｍｇ／Ｌ＋活性碳０．０３％;（２）分化和继代：Ｂ５＋ＫＴ０．５ｍｇ／Ｌ＋ＬＡＡ０．０５ｍｇ／Ｌ和Ｂ５＋ＫＴ２ｍｇ／Ｌ＋ＩＡＡｍｇ／Ｌ;（３）生根：Ｂ５＋ＩＡＡ０．５～２ｍｇ／Ｌ。     

无病毒苹果苗试管微繁技术研究

对经脱毒的优良苹果品种北海道９号、皇家嘎拉和长富２号进行了试管微繁技术的研究。结果表明：适合于３个品种试管苗增殖的培养基为ＭＳ＋６—ＢＡ０．５ｍｇ／Ｌ＋ＮＡＡ０．０５ｍｇ／Ｌ＋蔗糖３０ｇ／Ｌ,增殖率为２５～３,≥３ｃｍ的试管苗率约为５０％。通用的生根培养基为１／２ＭＳ＋ＩＡＡ０．５ｍｇ／Ｌ＋ＩＢＡ０．５ｍｇ／Ｌ＋ＮＡＡ０．１５ｍｇ／Ｌ＋蔗糖２５ｇ／Ｌ－肌醇,平均生根率保持在７５％左右。生根试管苗采用“一步法移栽”,平均成活率在７８％以上。     

黄脉爵床微体繁殖技术研究

对黄脉爵床（Ｓａｎｃｈｅｚｉａ ｎｏｂｉｌｉｓ Ｈｏｏｋ．ｆ．）微繁技术进行了研究并获成功。研究结果表明,外源植物生长调节剂及营养物质对试管芽苗增殖生长及其不定根诱导均有显著影响。试管芽苗在ＭＳ＋ＢＡ０．５ｍｇ／Ｌ＋ＺＴ０．５ｍｇ／Ｌ＋ＮＡＡ０．０３ｍｇ／Ｌ＋ＩＡＡ０．０３ｍｇ／Ｌ培养基上,可获得最大的单位芽苗数。ＭＳ（大量元素减半,肌醇１／４量）＋ＩＢＡ１．０ｍｇ／Ｌ（或ＮＡＡ０．２ｍｇ／Ｌ）＋     

苹果离体叶片特定部位体细胞胚胎发生和人工种子研究

以苹果品种嘎拉试管苗顶部前３片展开叶为试材,将叶片由叶尖至叶基分为上、中、下３个区,每区又由叶脉分隔为左、右两个亚区,共６个亚区。每一叶片在１个亚区中心部位用解剖针刺伤１点后接种于ＭＳ＋ＢＡ１ｍｇ／Ｌ＋ＮＡＡ４ｍｇ／Ｌ＋２,４－Ｄ０．５ｍｇ／Ｌ＋蔗糖２０ｇ／Ｌ的培养基上,暗培养７ｄ后,转接到ＭＳ＋ＢＡ１ｍｇ／Ｌ＋蔗糖２０ｇ／Ｌ的培养基上继续暗培养,４０ｄ后,８５％的叶片在刺伤口周围发生直接类型体细     

高维生素C水果Acerola的组织培养(简报)

１植物名称葡文为Ａｃｅｒｏｌａ（ＭａｌｐｉｇｈｉａｇｌａｂｒａＬｉｎｎ）。２材料类别成熟种胚。３培养条件（１）诱导种胚生长用１／２ＭＳ培养基,未添加任何激素;（２）诱导种胚愈伤组织培养基为ＭＳ＋２,４Ｄ２～３ｍｇ／Ｌ;（３）愈伤组织分化培养基为ＭＳ＋...     

珠美海棠组培苗繁殖技术的研究

以珠美涨棠为材料,研究了培养基配比、苗龄、琼脂等组培苗工厂化生产关键技术,光照条件和培养容器对组培苗生长发育的影响。结果表明,采用改良型培养基ＭＳ＋６－ＢＡ０．５ｍｇ／Ｌ＋ＩＡＡ０．２ｍｇ／Ｌ用于分化培养、１／２ＭＳ＋ＩＡＡ０．５ｍｇ／Ｌ或１／２ＭＳ＋ＩＢＡ０．５ｍｇ／Ｌ用于生根培养,苗龄３０－４０ｄ,使用接近国际标准的琼脂、光照强度１５００－２０００ｌｘ条例上生产的组培苗繁殖系数最大、有效苗最多     

Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage

Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.     

Assessing the effectiveness of conservation measures: Resolving the “wicked” problem of the Steller sea lion

“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.     

Enhanced establishment and growth of giant cardon cactus in an eroded field in the Sonoran Desert using native legume trees as nurse plants aided by plant growth-promoting microorganisms and compost

To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.     

Karyotypic and genome size variation in Cajanus cajan (L.) Millsp. (pigeonpea) and some wild relatives

Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.     

Effect of some fungicide seed treatments on the survival of Bradyrhizobium japonicum and on the nodulation and yield of soybean [Glycine max. (L) Merr.]

Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation.     

Einfluss der düngungsmethoden auf die entwicklung von zuckerrübenkrankheiten

Während neunjähriger (1994-2002) Untersuchungen in der Versuchsanstalt Ba?cyny (Fahlerde, Fall-Gleyboden, ausgebildet aus leichtem Lehmboden) wurde der Befall mit Krankheiten an der Zuckerrübe in Abhängigkeit von der Düngungsmethode bewertet. Folgende Methoden wurden angewendet: A - Mineraldünger, B - Stalldung und Mineraldünger, C - Stroh-, Gründung und Mineraldünger, D - Kompostdünger und Biopräparate (ökologische Düngung). Auf den Objekten A, B, C wurden bei konstanter Phosphor-Kalium-Düngung die Stickstoffgaben von 0 bis 180 kg.ha^?1 differenziert. Auf dem ökologischen Objekt D ohne Mineraldünger wurden statt Stickstoff die Biopräparate P₅₀₀ und P₅₀₁ verabreicht. Der geringste Befall von Krankheiten wurde an der Zuckerrübe auf jenem Objekt festgestellt, das mit Kompost und den Biopräparaten gedüngt worden war. Im Rahmen der konventionellen Düngungsmethoden wurde allgemein die höchste Intensität der Krankheiten an der mit Stroh, Gründung und Mineraldünger gedüngten Zuckerrübe beobachtet. Ausnahmen von dieser Regel bildete das Vorkommen von echtem Mehltau und Keimlingsfäule. Auf den Objekten A, B, C nahm die Intensität der Krankheiten mit der Steigerung der Stickstoffgabe zu. Auch die auf Objekt D verabreichten Biopräparate stimulierten die Entwicklung der Krankheiten. The effect of various fertilization methods on the diseases of sugar beet was estimated on the basis of nine-year studies (1994-2002) conducted in the Experimental Production Farm in Ba?cyny on loess-based, sedimentary-gley, light-clay soil. The following fertilization methods were applied: A - mineral fertilization, B - mineral and manure fertilization, C - straw, green manure and mineral fertilization, D - ecological compost and biodynamic preparations fertilization. In the objects A, B and C fertilized with phosphorus and potassium, various doses of nitrogen ranging from 0 to 180 kg/ha^?1 were used. In the ecological object D, where mineral fertilization was not used, biodynamic preparations P₅₀₀ and P₅₀₁ were applied instead of nitrogen. The lowest ratio of the diseases of sugar beet was observed in the object fertilized with the compost and biodynamic preparations. In view of the conventional fertilization methods, generally the highest incidence of diseases was noted in the sugar beet fertilized with straw, green manure and mineral fertilizers. The exception was the occurrence of powdery mildew and the black leg. In objects A, B and C the incidence of the diseases increased with the increase in nitrogen doses. The applied biodynamical preparations in the object D stimulated the development of diseases too.     

Prospects for control of Pythium damping-off of lettuce with Trichoderma,Gliocladium and Enterobacter spp.

Summary Damping-off of lettuce (Lactuca sativa) caused by Pythium ultimum was studied in pots containing a non-sterile potting mix in the glasshouse. Fifty P. ultimum sporangia g^-1 compost reduced the plant stand to 15% and shoot dry weight to 18%, but this reduction was totally prevented by applying Trichoderma harzianum at 2×10⁵ viable propagules g^-1 potting mix. Gliocladium virens and Enterobacter cloacae also alleviated the damping-off. E. cloacae did not adversely affect the action of the fungal antagonists. The co-existence of the bacterial and fungal antagonists was revealed on the root surface and inner surface of the testa by scanning electron microscopy, indicating the compatibility of the biocontrol agents.     

细菌、真菌及植物氮营养信号研究进展

氮素吸收代谢是所有生物生命活动的核心部分,因此,各种生物对氮的吸收与同化过程都有精细的调节。这种调节依赖于生物对体内氮素状况信号及体外（生长介质中）氮素信号的感受。过去几十年中,在细菌、真菌中已经对氮素营养信号有了较好的研究,而植物中则相对缓慢,但也有了一定的认识。本文重点比较细菌、真菌及植物中氮信号系统的组成,以期为进一步认识植物中的氮信号接受与转导系统提供启示。     

Aircraft operations near concentrations of birds in Antarctica: The development of practical guidelines

Aircraft operations have the potential to disturb and to impact negatively on bird life. A gradient of increasing behavioural response is evident in birds when exposed to increasing aircraft stimulus. The most major disturbance is likely to lead to impacts on the health, breeding performance and survival of individual birds, and perhaps bird colonies. A process of revision to policies on aircraft operations contained in management plans for a number of specially protected areas in Antarctica by the United Kingdom, accompanied by consultations made within the scientific community through the Scientific Committee on Antarctic Research (SCAR) and with operational interests through the Council of Managers of National Antarctic Programmes (COMNAP) resulted in new guidelines being adopted by the Antarctic Treaty Consultative Parties in June 2004. The principal recommendations of the guidelines are that bird colonies should not be overflown below 2000 ft (∼610 m) above ground level and landings within 1/2 nautical mile (∼930 m) of bird colonies should be avoided wherever possible. These guidelines are less stringent and less specific than those that were recommended by the SCAR specialist group on birds, and represent a compromise to accommodate operational needs. While the adoption of clear and consistent guidelines for the operation of aircraft in Antarctica is welcome in that this provides practical advice that is likely to reduce incidences of close aircraft/bird encounters, there remains insufficient knowledge of the interactions between aircraft and birds in Antarctica, and the consequent impacts on individual birds and on bird populations. It is important, therefore, that the guidelines adopted are considered interim, and should be kept under scrutiny with revisions made as new and improved research results appear.     

The abundance of heterocystous blue-green algae in rice soils and inocula used for application in rice fields

Summary Algal populations were quantified (as colony-forming units [CFU] per square centimetre) in 102 samples of rice soils from the Philippines, India, Malaysia and Portugal, and in 22 samples of soil-based inocula from four countries. Heterocystous blue-green algae (BGA) were present in all samples. Nostoc was the dominant genus in most samples, followed by Anabaena and Calothrix. In soils, heterocystous BGA occurred at densities ranging from 1.0 × 10² to 8.0 × 10⁶ CFU/cm² (median 6.4 × 10⁴) and comprised, on average, 9% of the total CFU of algae. Their abundance was positively correlated with the pH and the available P content of the soils. In soil-based inocula, heterocystous BGA occurred at densities ranging from 4.6 × 10⁴ to 2.8 × 10⁷ CFU/g dw (dry weight), comprising only a moderate fraction (average 13%) of the total algae. In most soils, the density of indigenous N₂-fixing BGA was usually higher than that attained by applying recommended rates of soil-based inoculum. Whereas research on the practical utilization of BGA has been mostly directed towards inoculation with foreign strains, our results suggest that attention should also be given to agricultural practices that enhance the growth of indigenous strains already adapted to local environmental conditions.Maître de Recherches ORSTOM (France), Visiting Scientist at IRRI