常见杨树天牛分类管理系统（CPLTMS）的研建

在国内首次以杨树天牛为研究对象,研制其分类管理系统（ＣＰＬＴＭＳ）,对系统特征提取、特征编码、各水平分类检索表自动生成以及图形处理等技术问题进行了研究。系统集成环境可以实现信息处理、检索表自动生成、更新及图形显示等功能。     

百合内源激素与鳞茎休眠及花芽分化关系的研究

以切花百合品种"雪皇后"、"西伯利亚"和"哥德琳娜"为试验材料,采用石蜡切片和扫描电镜的方法对百合花芽在不同分化时期进行形态学观察,采用酶联免疫吸附法测定百合内源激素的变化,利用DPS数据分析系统对试验结果进行主成分分析。结果表明:ABA和GA1 3在解除休眠中起着关键作用,为进一步研究百合鳞茎的休眠机理提供了重要线索。     

Abscisic acid and the regulation of embryo dormancy in the genus Acer

Germination of Acer pseudoplatanus L. and Acer platanoides L. seeds was increased by moist storage of the intact fruits (seed + pericarp) at 5 degrees C, but not at 17 degrees C. In both species, germinative capacity of isolated embryos (seeds with testa removed) was increased by moist storage of fruits at either 5 or 17 degrees C. Thus dormancy loss by intact seeds and excised embryos was not necessarily correlated. Loss of dormancy in isolated embryos was associated with a reduction in free abscisic acid (ABA) content. Embryos from freshly harvested fruits of A. pseudoplatanus had a higher germinative capacity and a lower free ABA content than embryos from freshly harvested fruits of A. platanoides. Morever, germinative capacity increased, and free ABA content decreased, more rapidly with length of fruit storage in A. platanoides embryos than in A. pseudoplatanus embryos.     

Influence of temperature on the dynamics of ATP,ADP and non-adenylic triphosphate nucleotides in vegetative and floral peach buds during dormancy

The nucleotides test of endodormancy, which is based on the capacity of tissues to synthesize ATP and non-adenylic triphosphate nucleotides (NTP), cannot be used for floral buds, and it is of questionable use for vegetative buds. In an attempt to find an alternative test, we examined whether the dormancy state of vegetative and floral buds of trees exposed to different temperature conditions during the rest period is directly related to their ATP, ADP and NTP concentrations and ATP/ADP ratio. Once the buds had entered endo- or paradormancy, the nucleotide concentrations and the ATP/ADP ratio were low in the vegetative primordia and very low in the floral primordia. Only after the action of chilling, when the buds were considered to have completed the endodormancy and paradormancy phases, did the nucleotide concentrations increase, accompanied by a steep rise in ATP/ADP ratio. We conclude that the ATP/ADP ratio could be used to characterize the bud dormancy state by comparison with critical values of 1.5 for vegetative primordia and 1.0 for floral primordia.     

沙棘酸乳中抗坏血酸含量的检测

用2，4-二硝基苯肼法对沙棘酸乳中抗坏血酸的含量进行检测。检测结果看出，沙棘酸乳中抗坏血酸的含量与沙棘果中抗坏血酸的含量基本相同，说明在沙棘酸乳制造过程中抗坏血酸很少被破坏。     

雷竹侧枝育苗造林技术试验研究

雷竹侧枝枝条应用ABT 1号生根粉不同浓度的溶液进行处理，蘸黄泥浆扦插育苗，母竹苗木应用ABT 3号生根粉蘸黄泥浆造林与雷竹侧枝、母竹苗木应用清水处理蘸黄泥浆直接扦插育苗、造林进行了对比试验。     

Genotypic variation in drought tolerance of poplar in relation to abscisic acid

We investigated effects of water stress and external abscisic acid (ABA) supply on shoot growth, stomatal conductance and water status in 1-year-old cuttings of a drought-sensitive poplar genotype Populus x euramericana cv. I-214 (Italica) and a drought-tolerant genotype P. 'popularis 35-44' (popularis). Populus popularis was more productive and maintained higher leaf water potentials throughout the drought treatment than cv. Italica. Supply of ABA to the xylem sap caused a greater decline in growth and more leaf abscission in shoots of cv. Italica than in shoots of P. popularis. Immediately after initiation of the drought treatment in P. popularis, the ABA concentration ([ABA]) of the xylem increased rapidly and stomatal conductance declined; however, stomatal conductance had returned to control values by the third day of the drought treatment, coincident with a gradual decline in xylem [ABA]. In contrast, xylem [ABA] of cv. Italica initially increased more slowly than that of P. popularis in response to the drought treatment, but the increase continued for 3 days at which time a tenfold increase in xylem [ABA] was observed that was followed by abscission of more than 40% of the leaves. We conclude that sensitivity of poplar roots to variation in soil water content varies by clone and that a rapid short-term accumulation of ABA in shoots in response to water stress may contribute to drought tolerance.     

Pretreatment of poplar by acid and alkali for enzymatic hydrolysis

Summary The dilute acid pretreatment in a plug flow reactor and alkali pretreatments with caustic solutions at different conditions followed by enzymatic hydrolysis resulted in drastically improved glucose yields for aspen and hybrid poplar. The acid pretreatment conditions must be carefully chosen to open the cellulosic structure allowing rapid diffusion of enzyme. The effectiveness of pretreatment is chiefly based on the enlargement of the pore size suitable for enzyme molecules.This work was carried out at Thayer School of Engineering, Dartmouth College in New Hampshire. The author wishes to express his gratitude to Prof. H. E. Grethlein for all kind support and helpful discussions     

湿地松幼林主、侧枝弯曲成因及防治研究

湿地松幼林主、侧枝弯曲是由于土壤、植株缺铜引起的一种生理性病变。采用喷施、根施硫酸铜及喷施硼砂加硫酸铜混合液的方法进行防治，结果表明喷施硼砂加硫酸铜混合液的防治效果达80．56％－91．67％，明显优于喷施和根施硫酸铜的防治效果。     

Comparison of manure compost and mineral fertilizer for hybrid poplar plantation establishment on boreal heavy clay soils

• Introduction   

Clay soils are typically rich in nutrients but are often compact and hard during summer increasing planting shock by limiting root development. Recycling farm manure in hybrid poplar plantations may offer additional benefits to mineral fertilizer as organic amendment can create better conditions for the early development of roots in addition to nutrient release.     

Silicon promotes the control of Meloidogyne incognita in lettuce by increasing ascorbic acid and phenolic compounds

Journal of Pest Science - Silicon (Si) has a physical barrier effect on plant tissues, decreasing nematode infection in different crops. Notwithstanding, research on lettuce is lacking, especially...     

An efficient method for clonal propagation and in vitro establishment of softwood shoots from epicormic buds of teak (Tectona grandis L.)

Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in teak (Tectona grandis L.). Higher number of shoots (6.17) per log was produced under natural light as compared to shade conditions. Forcing was also better in natural light as compared to shade in terms of shoot length, number of nodes or leaves. For rooting, 2–4 cm long softwood shoots were excised and treated with either indole-3-butyric acid (IBA) or α-naphthyl acetic acid (NAA) at 0, 1000, 2000 or 3000 μmol·L^–1 each or with combinations (1000 + 1000, 2000 + 2000 or 3000 + 3000 μmol·L^–1) and then placed in flat trays containing autoclaved sand at 25 ± 2ºC in 16 h photoperiod at 35 µmol·m^–2·s^–1. After 28 days, softwood cuttings treated with IBA + NAA (3000 + 3000 μmol·L–1) had highest rooting percentage (89.3%) with 5.5 mean roots. Shoot apex and nodal explants of softwood cuttings were pretreated with 0.1% (w/v) ascorbic acid, boric acid, activated charcoal, citric acid, glutamine or polyvinylpolypyrollidone (PVP) for 24 h to remove phenolic compounds before surface disinfestation. Glutamine (Gl) and PVP were equally effective resulting in 60% establishment of shoot apices on MS medium supplemented with 10 μmol·L–1 6-benzylaminopurine (BAP) + 5 μmol·L–1 NAA. Using shoot apices, highest (42.80) number of multiple shoots with 54.33 mm shoot length were obtained on MS + BAP (8.8 μmol·L–1) + IBA (2 μmol·L–1) after 45 days. Shoots were successfully rooted and acclimatized to greenhouse     

An efficient method for clonal propagation and in vitro establishment of softwood shoots from epicormic buds of teak （Tectona grandis L.）

Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in teak(Tectona grandis L.) . Higher number of shoots(6.17) per log was produced under natural light as compared to shade conditions. Forcing was also better in natural light as compared to shade in terms of shoot length,number of nodes or leaves. For rooting,2-4 cm long softwood shoots were excise...     

Overcoming seed dormancy of mooseer (Allium hirtifolium) through cold stratification, gibberellic acid, and acid scarification

Mooseer(Allium hirtifolium Boiss.) is bulbous perennial herb widely used in pharmaceutical and food industry in Iran.We studied germination of mooseer seeds in two separate experiments.In the first experiment,we evaluated four treatments:sulfuric acid scarification,sandpaper scarification,cold stratification,and gibberellic acid(GA 3) application.In the second experiment,we evaluated combinations of these treatments.All treatments in the first experiment had no effect on seed germination,suggesting that mooseer seeds have physical and physiological dormancy.In the second experiment,the highest germination percentage(86.6%) was observed after five minutes scarification with sulfuric acid(75% v/v),followed by 60 days of cold stratification.Duration of sulfuric acid scarification(5,10,and 20 min) did not affect germination rates,but increasing duration of cold stratification(from 15 to 60 days),increased germination from 28.3% to 86.6%.Our study showed that mooseer seeds have both physical and physiological dormancy.     

抗虫杨的组织培养

本研究报道采用茎切段生芽增殖方法繁殖抗虫杨。切段时采用一叶一段,在添加0.5-0.8mg／L IAA的改良MS培养基上生根、腋芽萌发长成完整植株。这种方法具有快速、变异率低、节约成本的优点。     

Preformation in vegetative buds of Prunus persica: factors influencing number of leaf primordia in overwintering buds

We investigated the influence of bud position, cultivar, tree age, tree carbohydrate status, sampling date, drought and light exposure on the number of leaf primordia formed in dormant vegetative peach buds (Prunus persica (L.) Batsch) relative to the number of primordia formed after bud break (neoformed). During winter dormancy, vegetative peach buds from California and Italy were dissected and the number of leaf primordia recorded. Between leaf drop and bud break, the number of leaf primordia doubled from about five to about 10. Parent shoot length, number of nodes on the parent shoot, cross-sectional area of the parent shoot, bud position along the parent shoot and bud cross-sectional area were correlated with the number of leaf primordia. Previous season light exposure, drought and tree carbohydrate status did not affect the number of leaf primordia present. The number of leaf primordia differed significantly among peach varieties and tree ages at leaf drop, but not at bud break. Our results indicate that neoformation accounted for all shoot growth beyond about 10 nodes. The predominance of neoformed shoot growth in peach allows this species great plasticity in its response to current-season conditions.     

Roles of gibberellins and abscisic acid in dormancy and germination of red bayberry (Myrica rubra) seeds

Intact seeds from freshly harvested fruits of Myrica rubra (Sieb et Zucc.) were dormant and required 8 weeks of warm stratification followed by 12 weeks of cold stratification for germination. Exogenous application of gibberellic acid (GA(3)) to intact fresh seeds was effective in breaking dormancy, with > 70% of seeds germinating when treated with 5.2 mM GA(3) and incubated at a day/night temperature of 30/20 degrees C for 20 weeks. Removing the hard endocarp or endocarp plus seed coat of fresh seeds promoted germination, and addition of GA(3) to the embryo accelerated germination. The gibberellins GA(1) and GA(4) were more effective than GA(3) in promoting germination of seeds with the endocarp removed. Endogenous contents of GA(1), GA(3), GA(4), GA(7) and GA(20) were quantified by gas chromatography-mass spectrometry-selected ion monitoring in the endocarps, seed coats and embryos of fresh seeds treated with 5.2 mM GA(3). The content of GA(3) decreased in the endocarp during incubation, whereas GA(1) contents increased in the endocarp and seed coat. A high GA(1) content was detected in the endocarps and embryos of newly germinated seeds. We speculate that GA(3) was converted to GA(1) during incubation and that GA(1) is involved in seed germination. Endogenous abscisic acid (ABA) contents were measured in fresh seeds and in warm and cold stratified seeds. The ABA content in fresh seeds was distributed in the order endocarp > seed coat > embryo, with the content in the endocarp being about 132-fold higher than in the seed coat and embryo. Total ABA content of seeds subjected to warm or cold stratification, or both, was 8.7- to 14.0-fold lower than that of fresh seeds. Low contents of endogenous GA(1), GA(3), GA(7) and GA(20), but elevated contents of GA(4), were found in the seed coats and endocarps of warm plus cold stratified seeds and in the seed coats and embryos of newly germinated seeds. These observations, coupled with the finding that GA stimulated germination of dormant Myrica seeds, provide evidence that endogenous ABA inhibited release of dormancy and that endogenous gibberellins, especially GA(4) or GA(1), or both, are involved in germination.