The taxonomic status of closely related closed cone pines in Mexico and Central America

A taxonomic study on 14 cone and needle traits of 281 trees from 33 provenances of Pinus oocarpa, P. oocarpa var. ochoterenae, P. patula var. longipedunculata, P. patula var. patula and P. tecunumanii in Central America and Mexico was conducted to quantify the affinity between closely related species. A second objective was to determine the geographic range of P. tecunumanii in Mexico. Cluster analysis placed 52% of all provenances in taxa different from those assigned by field foresters. Trees from 15 provenances of what was locally known as Pinus oocarpa var. ochoterenae from Chiapas were statistically indistinguishable from high elevation Central American sources of P. tecuncumanii when assessed for cone and needle characteristics. However, trees from two provenances known locally as P. oocarpa var. ochoterenae from southwestern Oaxaca, Juquila and Tlacuache, were found to be distinct from P. tecunumanii and may be a variant of P. patula. Canonical discriminant analysis was used to determine the taxonomic affinity among newly formed clusters. The spatial (Mahalanobis) distance between P. tecunumanii and P. patula var. patula, P. patula var. longipedunculata, and P. oocarpa was 42.0, 44.4, and 109.4 respectively, and highly significant. The geographic range of Pinus tecunumanii in Mexico appears to be confined to the state of Chiapas.     

Effects of some materials extracted fromAjuga species on the larvae ofHyphantria cunea and its natural enemies

Six kinds of extracts drawn fromAjuga multiflora andA. multiflora var.brevispicata and A. multiflora var.serotina using methanol and acetone were used in this experiment to test their killing activity to the second instar larvae ofHyphantria cunea and their influence on its natural enemies. The average death rate caused by those extracts on the second instar larvae was 85.70%. The mortality rate caused by the extracts drawn with methanol was from 88.89% to 96.33%, which was significantly higher than that caused by acetone extracts. Those extracts were safe toTrichogramma dendrolimi, Coccinella septempunctata, the natural enemies ofH. cunea. We did not found any evidence shown that those extracts had any influence the emergence and the development ofT. dendrolimi. Those methanolic extracts gotten fromA. multiflora andA. multiflora var.brevispicata had no significant effects on the mortality of the larvae and adults ofC. septempunctata. Those extracts could be used in the control ofH. cunea safely. The research was sponsored by National Nature Science Fundation (39470586) (Responsible Editor: Chai Ruihai)     

Fumigant and repellent activities of essential oil from <Emphasis Type="Italic">Coriandrum sativum</Emphasis> (L.) (Apiaceae) against red flour beetle <Emphasis Type="Italic">Tribolium castaneum</Emphasis> (Herbst) (Coleoptera: Tenebrionidae)

The biological activity of essential oil extracted from coriander, Coriandrum sativum L. (Apiaceae) against eggs, larvae and adults of Tribolium castaneum (Herbst) was investigated in a series of laboratory experiments. Bioassays conducted in air-tight glass chambers showed vapour toxicity and strong repellency on filter paper arena test towards all the stages used. Responses varied significantly (P < 0.001) within insect stages, dosages and exposures. At 12.0 μg/ml dosage, mortality of adults reached 95%, but for 12-, 14- and 16-days larvae, mortalities were 65, 74 and 82%, respectively. On the developmental inhibition, individuals fumigated at the larval stage confirmed that the percentage of larvae reaching to pupal stage and pupae to adult stage, decreased significantly (P < 0.001) with increasing dosage concentration. The oil fumigation yielded 100% mortality for T. castaneum larvae, pupae and adults at 0.08 μg/ml dosage. The oil had fumigant activity against eggs and the toxicity progressively increased with increased exposure times and concentrations. One hundred per cent T. castaneum egg mortalities were obtained with oil fumigation at 20 μg/ml and 96 h exposure period. C. sativum oil also showed highly repellent activity to the adults of T. castaneum, with overall repellency was 90% and at a dosage of 12 μg/ml repellency was 100% in a filter-paper arena test.     

Fusarium spp. and Pinus strobus seedlings: root disease pathogens and taxa associated with seed

Eastern white pine (Pinus strobus L.) seeds weresown in soil infested with Fusarium proliferatum, rootnecrosis developed on seedling roots, and F. proliferatumwas reisolated from symptomatic roots; thus, demonstrating thatF. proliferatum is pathogenic toeastern white pine seedlings. Soils infested with F.acuminatum or F. sporotrichioides resulted infew diseased seedlings. Seedlings with root rot generally showed reductions inseedling height. All Fusarium species tested wererecoveredfrom rhizosphere soil samples. Three seedlots of Pinusstrobus were examined for Fusarium infestation.Fusarium species were recovered from most seeds in twoseedlots. Fusarium proliferatum and F.sporotrichioides were the predominant species isolated. Additionalspecies not previously reported from P. strobus included:F. acuminatum, F. chlamydosporum,F. equiseti, F. graminearum,F. moniliforme, F. poae, F.polyphialidicum, F. heterosporum, F.sambucinum, and F. semitectum.     

Effect of Lecanicillium muscarium on Eretmocerus sp. nr. furuhashii (Hymenoptera: Aphelinidae), a parasitoid of Bemisia tabaci (Hemiptera: Aleyrodidae)

Pathogenicity of Lecanicillium muscarium, against Eretmocerus sp. nr. furuhashii (Hymenoptera: Aphelinidae), was investigated under laboratory conditions to determine if the fungal infection of the whitefly host can effect the survival, longevity and fecundity of female parasitoid. The results indicated that the number of parasitized larvae surviving a L. muscarium treatment after 6 days of oviposition decreased with increasing concentrations of L. muscarium and in later stages of development (12 days post oviposition) were not affected by fungal application. There were no significant differences on adult parasitoid survivorship after 7 days among all treatments. Maximum survivorship (73.33%) was observed for control and it was minimum (60%) at 1 × 10⁸ conidia/ml. L. muscarium showed a non significant effect on longevity and next offsprings of female parasitoids. The percentage emergence of parasitoids from the whitefly nymphs produced by the females emerged from treated pupae was almost similar. Maximum emergence (69.77%) was observed at 1 × 10⁶ conidia/ml and it was lowest (61.02%) at conidial concentration of 1 × 10⁸ conidia/ml. Maximum longevity of adult Eretmocerus sp. emerging from whitefly nymphs when treated after 12 days of postoviposition was observed for 1 × 10⁵ conidia/ml having a mean value of 5 days whereas the lowest longevity was 4.9 days observed at 1 × 10⁸ conidia/ml. The results mentioned above indicate that the interaction among biocontrol agents is positive to a greater extent with minimum risk hazards.     

Response of slash pine planted on mounds in central and southwestern Louisiana

On two silt loam flatwoods in Louisiana, use of mounds as planting sites for slash pine (Pinus elliottii Engelm. var. elliottii) was shown to be more effective than planting without mounds (untreated control) after six growing seasons in the field. Mounds formed were of two sizes: low mounds made of 550 dm³ of soil and high mounds made of 1,000 dm³ of soil. One site was in central Louisiana and had two drainage classes: a somewhat poorly drained Caddo-Messer complex and a poorly drained Caddo soil. On both drainage classes, pine survival was not affected by treatment, but the incidence of fusiform rust galls on the main stem (caused by Cronartium quercuum (Berk.) Miyabe ex Shirai f. sp. fusiforme Burdsall and Snow) was greater on trees planted on mounds. The second site was a poorly drained Caddo soil in southwestern Louisiana. At this site, there were fewer surviving pines on controls than on mounds, but the incidence of rust galls was not affected by treatment. At both sites, pines were taller and had a greater mean diameter at breast height on mounds than on controls. Mound size did not influence tree size at either site.     

Minor pregnanes from Caralluma adscendens var. gracilis and Caralluma pauciflora

Phytochemical investigation of Caralluma adscendens var. gracilis and Caralluma pauciflora (Asclepiadaceae) whole plant extracts allowed to isolate one pregnane glycoside and two pregnanes characterized as 12β,20-O-dibenzoyl-5α,6-dihydrosarcostin β-oleandropyranosyl-(1→4)-β-cymaropyranosyl-(1→4)-β-digitoxypyranosyl-(1→4)-β-cymaropyranosyl-(1→4)-β-cymaropyranoside (1), 12β-O-benzoyl-3β,11α,14β,20R-pentahydroxy-pregn-5-ene (2), and 11α-O-benzoyl-3β,12β,14β,20R-pentahydroxy-pregn-5-ene (3), respectively. Their structural characterization was obtained on the basis of extensive NMR spectral studies. Three known pregnane glycosides along with lupeol and β-sitosterol were also isolated and characterized.     

Prescribed burning and hexazinone herbicide as release treatments in a sapling hardwood-loblolly pine stand

To compare release treatments, a randomized complete block study was established in a 7-year-old hardwood-loblolly pine (Pinus taeda L.) stand in central Louisiana established using chopping and burning. There were 5 blocks of 3 treatments each: (1) check, (2) hexazinone applied once, and (3) prescribed backfiring applied twice. The first burn in December 1985 (7 years after site preparation) had a fire intensity of 90 kJ/s/m. The hexazinone herbicide was applied in April 1986 (the 8th year after site preparation) with a metered spotgun applicator at a rate of 3.0 kg active ingredient/ha. The second burn in March 1989 (the 11th year after site preparation) had a fire intensity of 106 kJ/s/m.The two prescribed burns increased the number of stems less than 1.5 m tall from 1,380 to 2,960/ha red maple (Acer rubrum L.), blackgum (Nyssa sylvatica var. bifora), and sweetgum (Liquidambar styraciflua L.). Burning reduced the number of loblolly pines less than 2.0 m tall, which resulted in a significant increase in average loblolly pine height and diameter. Loblolly pine comprised 62 and 59% of the basal area on the check and burn treatments, respectively, 11 years after site preparation. Hexazinone reduced the number of blackgum, sweetgum, and oak (Quercus spp.) from 6,100 to 4,560 stems/ha and resulted in significantly less hardwood tree basal area than found on the check or burn treatments. Therefore, the herbicide treatment resulted in principally a loblolly pine stand (over 80% of the total tree basal area was pine) four years after hexazinone application.     

Intraspecific geographic variation and primary selection on the best provenance ofPinus sylvestris var.mongolica

This paper summarizes the result from the provenance test of eight years oldPinus sylvestris var.mongolica in Liangshui Natural Reserve comprehensively. The main contents include:(l) the geographic variation of the growth characters ofPinus sylvestris var. mongolica, tends to negative change gradually at latitude and has obvious climatic nature, (2) no significant difference exists in the morphological adaptability and resistant characteristics and so on; (3)on the basis of the geographic variation study on the growth characteristics, the provenances ofPinus sylvestris var.mongolica were classified into two geographic populations and two subpopulations as follows: the northern population of the Daxing’an Mountain (I) and the southern population of the Daxing’an Mountain as well as the Xiaoxing’an Mountain (II), which includes Honghuarji subpopulation (II -1) and Kalunshan subpopulation (II-2). (4) the height growth rhythm was analyzed according to the divided population and subpopulation; (5) the best provenance was selected for the Liangshui Natural Reserve and its neighborhood according to the results from SSR test of the growth characteristics (the breast height diameter and height of eight year old trees), the possibility of the early provenance selection was also verified by the method of order correlation analysis on the height growth of three, five, seven and eight years old provenances.     

Nursery soil cover influences germination of Thujopsis dolabrata var. hondai seeds

We examined the influence of nursery soil cover on germination of Thujopsis dolabrata var. hondai. Seeds were sown under seeding bed conditions: (1) nursery soil (andosol) without soil cover, (2) Kanuma pumice without soil cover, (3) nursery soil with nursery soil cover, and (4) nursery soil with sterilized sand cover. Germination percentages were compared between these conditions. The germination percentage (8.8%) at 10 weeks after sowing under condition 3 was significantly lower than under conditions 1, 2, and 4 (56.8%, 52.0%, and 47.2%, respectively). Of the nongerminated seeds under condition 3, 75.0% were decayed and several fungi were isolated from decayed seeds. An inoculation test of isolated fungi Cylindrocarpon tenue, Cylindrocarpon sp., Fusarium oxysporum, and Botrytis sp. to seeds showed that these fungi caused seed decay. Our results indicated that nursery soil cover may not be suitable for T. dolabrata var. hondai seeds sown in nursery soil because of seed decay by pathogens.     

Agrobacterium-mediated transformation of lombardy poplar (Populus nigra L. var.italica Koehne) using stem segments

Genetically transformed lombardy poplar (Populus nigra L. var.italica Koehne) plants were regenerated by co-cultivation of stem segments withAgrobacterium tumefaciens strain LBA4404 that harbored a binary vector (pBI121) which included genes for β-glucuronidase (GUS) and neomycin phosphotransferase. Successful transformation was confirmed by the ability of stem segments to produce calli in the presence of kanamycin, histochemical and fluorometric assays of GUS activity in plant tissues, and Southern blot analysis.     

沙地樟子松天然纯林的结构特征

[目的]为了解红花尔基地区沙地樟子松天然纯林的结构特征,指导沙地樟子松的保护与经营。[方法]在红花尔基地区设置2块100 m×100 m的樟子松天然纯林固定样地,利用样地内每木定位调查数据和分析统计软件进行一元分布及二元分布特征分析。[结果](1)樟子松天然林纯林直径分布为单峰或多峰山状分布,垂直结构简单,只有乔木层和草本层。(2)樟子松天然纯林的林木分布格局为均匀分布,接近随机分布,林木分布格局类型与林分密度无关;林分中樟子松个体竞争激烈,多数单元中林木呈较密集状态。(3)2块样地中随机分布状态下的林木多数为中等密集或比较密集,不同分布状态下的林木优劣性差异较小;低密度樟子松天然纯林中多数密集状态的林木为绝对优势木或优势木,而高密度林分中林木密集度分布与林木大小无关。[结论]红花尔基沙地樟子松天然林结构不合理,应选择病腐木及聚集分布的个体作为潜在调整对象,进行密度调整和结构优化。     

Development of transgenic hybrid sweetgum (<Emphasis Type="Italic">Liquidambar styraciflua</Emphasis> × <Emphasis Type="Italic">L. formosana</Emphasis>) expressing γ-glutamylcysteine synthetase or mercuric reductase for phytoremediation of mercury pollution

Using Agrobacterium-mediated gene transfer, we generated transgenic hybrid sweetgum (Liquidambar styraciflua × L. formosana) overexpressing two types of genes to enhance plant remediation of mercury-contaminated soil and water: bacterial γ-glutamylcysteine synthetase gene (ECS), the first and most important enzyme in phytochelatin synthesis, or various genes encoding a mercuric ion reductase (merA9, merA18, merA77). Hybrid sweetgum proembryogenic masses (PEMs) constitutively overexpressing ECS were able to grow in the presence of 50 μM HgCl₂, which inhibited wild-type PEMs, but plantlets regenerated from the PEMs had abnormal form and did not survive for more than a few weeks following germination. In contrast, mature somatic embryos generated from PEMs constitutively overexpressing merA9 and merA18 converted to normal plantlets on germination medium containing 25 μM HgCl₂, while control embryos were killed on 25 μM Hg(II)-medium. Transgenic merA plantlets displayed enhanced resistance to Hg(II) and released Hg(0) two to three times more efficiently than the wild-type plantlets.     

Ectomycorrhizal development on pine by Pisolithus tinctorius in bare-root and container seedling nurseries

Vegetative inoculum of Pisolithus tinctorius (Pt) produced by Sylvan Spawn Laboratories (C:N 50) and by research methods (IMRD), spore-encapsulated seeds, spore pellets, and sprayed spores were compared for efficacy in forming Pt ectomycorrhizae on pines in operational bare-root nurseries in South Carolina, Florida, and Indiana and in microplots and containers in Georgia. Two rates of application (0.33 and 0.16 liter/m² of soil) of both sources of vegetative inoculum were similar in effect and formed abundant Pt ectomycorrhizae (Pt index > 50) and fruit bodies in all studies. Spore treatments formed consistently fewer Pt ectomycorrhizae than vegetative inoculum. The most effective spore treatment was spore encapsulated seeds. These results indicate that at a bed density of 270 seedlings/m², 0.6 to 0.7 liter of vegetative inoculum is needed to obtain Pt indices > 50 on 1,000 pine seedlings.     

Structure identification for compound I separated and purified fromtaxoids-produced endophytic fungi （Alternaria. alternata var. taxi 1011）

Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active compounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source.Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Altemaria. altemata var.taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type Ⅲ, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a completed method for separation and purification of the endophytic fungi as well as structure identification of its fermentation metabolite     

花吊丝竹居群遗传多样性的ISSR分析

[目的]研究花吊丝竹居群遗传多样性和遗传结构,为种质资源有效利用和良种选育提供理论指导。[方法]利用12条ISSR引物对48份种质(共3个居群)花吊丝竹居群进行遗传多样性和遗传距离分析。[结果]共检测到124个位点,其中,多态性位点为102个,种质和居群水平上的多态位点百分比(PPB)分别为82. 26%和50. 27%,Ne’基因多样性指数(He)分别为0. 220 4和0. 206 6,Shannon’s信息指数(I)分别为0. 349 4和0. 300 5,表明花吊丝竹居群间存在中等水平的遗传变异。根据Nei’s遗传多样性计算出不同居群间分化水平(Gst)=0. 163 3,表明16. 33%的遗传变异存在于居群间,居群内的遗传变异为83. 67%。居群间的基因流Nm为2. 562 1,表明花吊丝竹居群间存在较大基因流,很大程度减少居群间遗传差异。基于遗传距离的UPGMA聚类结果表明,48份种质可分为3组,3个居群可分为2组,居群间地理距离与亲缘关系无显著相关性。[结论]虽然花吊丝竹主要靠营养生殖来繁衍后代,其居群遗传多样性较丰富,且居群内遗传多样性大于居群间。此外,福建居群遗传多样性明显高于广西和广东地区居群。     

Effects of Eucalyptus obliqua (L'Herit) density on young stands of even-aged Pinus radiata (D. Don)

In a 10-year-old Pinus radiata plantation, increasing densities of Eucalyptus obliqua, a woody weed species, caused reductions in the canopy leaf area and total stem volume of P. radiata. As the density of E. obliqua increased stand volume (the sum of stem volumes of the two species) was constant, but the sum of projected leaf area of the two species decreased. Higher E. obliqua density also resulted in higher mean height to diameter ratio of P. radiata. With increasing E. obliqua density the size distribution of P. radiata became more positively skewed and the size hierarchy of P. radiata increased. The effects of E. obliqua density on P. radiata are more likely due to below-ground competition than competition for light above-ground. Understanding the effects of E. obliqua density on the characteristics of P. radiata can benefit weed control programs and subsequent management of plantations with naturally regenerated E. obliqua.     

Two new flavonoids from Retama raetam

Two new flavones were isolated from the aerial parts of Retama raetam subsp. raetam. Their structures were established as luteolin 4′-O-neohesperidoside (1) and 5,4′-dihydroxy-(3″,4″-dihydro-3″,4″-dihydroxy)-2″,2″-dimethylpyrano-(5″,6″:7,8)-flavone (2) by means of spectroscopic methods. Also present was ephedroidin (4′,5,7-trihydroxy-8-(2-hydroxy-3-butenyl)-flavone).     

Cytotaxonomy and cytogeography ofVicia sect.Vicilla in Northeast of china

Vicia amirensis has pollen grain with swollen mesocipium, terete style, abaxially sprouting stylar hairs and globes stigma, differing from other five species,V. amoena, V. japonica, V. pseudo-orbus, V. ramuliflora, V. unijuga andV. venosa, in sect.Vicilla of Kupicha’s System. This result further support taxonomic treatmentV. amurensis proposed by Endo and Ohash. The chromosome numbers of 64 populations and karyotypes of 15 populations for sect.Vicilla and sect.Amurense were observed.V. amurensis andV. psendo-orbus have similar karyotype features such as the same karyotype symmetry, comparable chromosome size and the same type, of Sat-chromosomes, and thereforeV. amurensis in seet.Amurense is assumed to be closely related toV. japonica in sect.Vicilla. The primary study of nuclear DNA amount was carried out on nine populations of six taxa in sect.Vicilla in China. It is primarily discussed that evolutionary trend of karyotype, nuclear DNA amount in sect.Vicilla and geographic distribution of different ploidy cytotypes. (Responsible Editor: Zhu Hong)     

柏类引种试验研究

对柏类４个树种墨西哥柏,绿干柏,垂柏,巨柏共１２个种源的引种表明,不同树种和种源树高,胸径增最大年份分别出现在造林后第４年和第５年;造林后１０ａ,lay status