Rapid selection of catechin-rich tea trees (Camellia sinensis) by a colorimetric method

A rapid and efficient colorimetric method based on the use of Fast Blue B-salt (FBB) was established to select catechin-rich tea trees (Camellia sinensis L.). The catechin levels measured by the colorimetric method under optimized reaction conditions correlated closely with estimations by high-performance liquid chromatography (HPLC) analysis. The FBB colorimetric method was successfully used to classify 160 tea trees on the basis of their catechin contents into rich and poor lines. HPLC analysis of the FBB-selected tea tree extracts showed them to contain (−)-epigallocatechin 186 mg/g in tea tree line HR-29, (−)-epicatechin 43.7 mg/g in HR-82, (−)-epigallocatechin gallate 4.32 mg/g in HR-29, and (−)-epicatechin gallate 0.22 mg/g in HR-52. Classification of tea trees from the Hadong region into catechin-rich and -poor trees was independent of the growing season. Thus the FBB colorimetric method could find application as a reliable tool in screening and selection of tea trees on the basis of their catechin content.     

Allelic variation in the coumarate 3-hydroxylase gene associated with wood properties of Catalpa fargesii Bur.

Coumarate 3-hydroxylase(C3h)genes partici-pate in the synthesis of lignin and may affect the proper-ties of wood that are important for its commercial value.A b...     

不同套种模式油茶幼林水土流失及养分损耗

油茶(Camellia oleifera)是我国亚热带地区特有的最重要的木本油料树种之一,亦是世界四大木本油料树种之一(何方等,2004).油茶在长江流域以南各地广泛栽培.     

Genetic diversity and bark physiology of the European beech (Fagus sylvatica): a coevolutionary relationship with the beech scale (Cryptococcus fagisuga)

In 1994 and 1995, the degree of infestation by the beech scale (Cryptococcus fagisuga Lind.) was recorded on 120 beech trees (Fagus sylvatica L.) in the Pless Forest near G?ttingen, Germany. Simultaneously, the trees were characterized genetically and compounds of primary and secondary metabolism of beech bark were analyzed. A correlation was established between beech scale infestation and the genotype of the host trees, based on gene locus A of isocitrate dehydrogenase (IDH-A). The fraction of infested beech trees was higher in the heterozygous genotype A2A3 group than in the homozygous genotype A2A2 and A3A3 groups, whereas the fraction of beech trees with decreasing infestation from one year to the next was lower in the heterozygous genotype A2A3 group than in the homozygous genotype A2A2 and A3A3 groups. Concentrations of soluble carbohydrates, protein amino acids and proanthocyanidins were determined in the inner and outer bark of trees with differing degrees of infestation. The results indicate that the defense reaction of beech against infestation by beech scale comprises multiple processes in which nutrient availability to the beech scale is reduced by concentration shifts and by the formation of inhibiting compounds.     

Polyphenol oxidase and its relationship with oleuropein concentration in fruits and leaves of olive (Olea europaea) cv. 'Picual' trees during fruit ripening

Oleuropein, the main phenolic compound of olive fruit, has important antioxidant properties that are responsible for some of the nutritional properties of fruits and the defence mechanism of leaves. Polyphenol oxidase (PPO) activity changes during fruit ripening in many plants. We studied the kinetics and molecular properties of PPO in fruits and leaves of olive (Olea europaea L.) cv. 'Picual' trees and the relationship between PPO and oleuropein concentration during fruit ripening. Polyphenol oxidase showed hyperbolic kinetics in fruits and leaves. Significant increases in PPO specific activity, V(max), K(m )and catalytic efficiency occurred during fruit ripening. Based on SDS-PAGE under partially denaturing conditions and in-gel staining with DL-3,4-dihydroxyphenylalanine, PPO activity was found in one major protein of 55 and 50 kDA in fruits and leaves, respectively. During the last stages of fruit maturation, a second 36 kDa protein was observed in fruits but not in leaves, indicating that this protein could serve as a marker of the final phase of fruit maturation. Under fully denaturing conditions, only one 27.7 kDa immunoreactive band was detected in fruits. Both the amount of PPO activity and the amount of PPO protein increased significantly during fruit maturation. Immunohistochemical studies indicated that PPO is located in the epidermis, parenchyma and companion vascular cells of leaves as well as in the epidermis of fruit. During fruit maturation, oleuropein concentration measured by HPLC significantly decreased in fruits and increased in leaves.     

Rapid field measurement of the assimilation rate versus internal CO(2) concentration relationship in green ash (Fraxinus pennsylvanica Marsh.): the influence of light intensity

Assimilation rate (A) versus intercellular CO(2) concentration (C(i)) relationships for leaflets of five-year-old green ash (Fraxinus pennsylvanica Marsh.) trees were computed from gas exchange measurements obtained in the field with a closed-circuit, portable photosynthesis measurement system comprising an LI-6200 gas analyzer and an LI-6000 computer, (Li-Cor, Inc., Lincoln, Nebraska, USA). Observations were made over a range of light intensities achieved by attenuating direct sunlight with neutral density filters, and over a range of ambient CO(2) concentrations achieved by breathing into the assimilation chamber and then lowering the CO(2) concentration to the desired level with the LI-6200's soda-lime scrubber. Boundary layer conductance was determined by use of a leaf replica made of moist filter paper. Typically, A-C(i) curves at four light intensities were obtained in three to four hours. The initial slope (when A = 0) of the A-C(i) curve obtained at a light intensity of 1750 micromol m(-2) s(-1) (full sunlight) was similar to that obtained at a light intensity of 840 micromol m(-2) s(-1). However, when light intensity was reduced further (to 370 and 160 micromol m(-2) s(-1)), the initial slope of the A-C(i) curve also decreased, indicating that at these light intensities, assimilation was limited by photochemical energy supply, as well as CO(2) concentration.     

Growth and elemental composition (C,N, H) in larvae and early juveniles of a South American salt marsh crab,Chasmagnathus granulata (Decapoda: Grapsidae)

The semiterrestrial grapsid crab Chasmagnathus granulata Dana is one of the most predominant inhabitants of brackish salt marsh ecosystems in South America. Its early postembryonic stages were reared in the laboratory from hatching of the first larval stage through the first juvenile crab instar, and changes in the quantity and elemental composition of biomass (measured as dry weight, W; carbon, C; nitrogen, N; hydrogen, H) were investigated in short intervals of time (every 1 or 2 d). In a series of successive developmental stages, the accumulation of biomass per individual can be described as an exponential function of the number of moults. In contrast, the pattern of growth within individual moulting cycles is described with best fit of observed and predicted data as a quadratic function of development time elapsed since last ecdysis. Weight-specific instantaneous growth rates show decreasing trends within the moulting cycle. Cumulative biomass increments during larval development of C. granulata are among the highest on record for brachyuran crabs. The quantities and patterns of larval growth are in this species similar as in most marine brachyuran crabs, for which data are available, but different from those in some other semiterrestrial grapsid crab species, which live in similar brackish water habitats as C. granulata. Hence, the early postembryonic stages of C. granulata do not show special bioenergetic adaptations to the non-marine conditions, which prevail in the adult habitat of this species. This reflects a strategy of larval export to the sea, i.e. a reproductive dependence of this species on the marine environment.     

Neem-based integrated approaches for the management of tea mosquito bug, <Emphasis Type="Italic">Helopeltis theivora</Emphasis> Waterhouse (Miridae: Heteroptera) in tea

Despite continuous use of synthetic insecticides during last two decades, the tea mosquito bug, Helopeltis theivora Waterhouse (Miridae: Heteroptera), has become the most destructive sucking pest of tea in North East India. In order to reduce the load of the synthetic chemicals in tea vis-à-vis their deleterious effect, integration of biopesticide, synthetic pesticides along with effective spraying strategies, have been attempted. The anti-insect property of “neem”, Azadirachta indica A. Juss. (Meliaceae), has been used to solve many pest problems. In this study, different azadirachtin concentrations were evaluated at different doses against the H. theivora to find out their controlling efficacy. At 50,000 ppm azadirachtin concentration 65% control of infestation could be attained, whereas at 3,000 and 10,000 ppm, gave 30–43% reduction and 300 and 1,500 ppm <30% control was possible. Further in case of 3,000 and 10,000 ppm, azadirachtin concentration 30–43% reduction was registered. Therefore, azadirachtin concentration and its dilutions are the major criteria for getting desired bioactivity. Treatments with combined formulations viz. “neem + endosulfan” or “neem + deltamethrin” recorded significant reduction in H. theivora incidence even at reduced doses, as compared to sole application of neem or synthetic insecticide at recommended doses. Effective combinations and dose of the insecticides along with their formulations in controlling H. theivora have been presented and discussed.     

Field efficacy of a biopesticide prepared from <Emphasis Type="Italic">Clerodendrum viscosum</Emphasis> Vent. (Verbenaceae) against two major tea pests in the sub Himalayan tea plantation of North Bengal,India

The toxicity of four concentrations (1, 5, 10 and 20% w/v) of an aqueous extract from the weed, Clerodendrum viscosum Ventenat (Verbenaceae) was investigated under field conditions of the North Bengal University, Darjeeling, West Bengal, India for managing two major pests of tea, Camellia sinensis (L), namely the tea mosquito bug, Helopeltis theivora Waterhouse, (Heteroptera: Miridae) and the tea red spider mite, Oligonychus coffeae Nietner, (Acarina: Tetranychidae). Four field trials, two for red spider mite and two for tea mosquito bug, were conducted during April–May 2008 and October–November 2009 following a Randomized Block design. The aqueous extract of C. viscosum effectively and significantly reduced the mite population as well as infestation of tea mosquito bug by 68–95% and 73–86%, respectively, and their bioefficacy is comparable to synthetic and neem pesticides. No phytotoxic effect (score 0–5% and grade 1) was observed in the tea bushes sprayed with different doses of aqueous extract of C. viscosum in the field. Made tea samples were taint free. Organoleptic test revealed leaf-infusions and liquor strength as good, scoring 6.5–7.0 on a 10 point scale. Availability and distribution of this weed (C. viscosum) in and around tea-growing areas of sub Himalayan region, along with its processing for the feasibility of including C. visosum extracts in the current IPM programme is discussed.     

Morphological changes in sugi (Cryptomeria japonica) wood after treatment with the ionic liquid, 1-ethyl-3-methylimidazolium chloride

We investigated morphological changes in wood tissues of sugi (Cryptomeria japonica) resulting from treatment with the ionic liquid 1-ethyl-3-methylimidazolium chloride ([C2mim][Cl]), which dissolves cellulose. Treatment with [C2mim][Cl] caused dissociation and distortion of tracheids in latewood, but not in earlywood. This difference was due to the difference in swelling behavior of the cell wall between earlywood and latewood. Many pit membranes in bordered pits were broken by treatment with [C2mim][Cl]. In addition, some chemical changes in wood components, such as cellulose and lignin, occurred before significant disruption or destruction of the cell wall. Our results show that the reaction of wood liquefaction by [C2mim][Cl] treatment is not homogeneous, both from chemical and morphological viewpoints.     

Analysis of the relationships among O(3) uptake, conductance, and photosynthesis in needles of Pinus ponderosa

We studied the effects of O(3) uptake on conductance (g(wv)) and photosynthesis (A) in needles of ponderosa pine (Pinus ponderosa Laws.) seedlings exposed for 70 days to one of three O(3) regimes-Low-O(3) (0.1 micro mol mol(-1) daily peak), High-O(3) (0.2 micro mol mol(-1) daily peak), and Low/High-O(3) (alternating 2 days Low-O(3) and 2 days High-O(3)). Seedlings exposed to charcoal-filtered air served as controls. Total O(3) exposures, expressed as ppm-h (the sum of the average hourly concentration in ppm ( micro mol mol(-1)) over the exposure period), were 77, 135, 105 and 4 for the Low-O(3), High-O(3), Low/High-O(3) and control treatments, respectively. Conductance (g(wv)) declined to about 60% of the value in control seedlings by Day 6 in seedlings in the High-O(3) treatment and by Day 37 in seedlings in the Low/High-O(3) treatment, but g(wv) did not decline at all in seedlings in the Low-O(3) treatment. At the end of the 70-day experiment, cumulative O(3) uptake, calculated from measured g(wv) values and assuming an internal O(3) concentration of zero, was 12.2, 13.5, and 14.7 mmol m(-2) for seedlings in the Low-O(3), Low/High-O(3), and High-O(3) treatments, respectively; however, O(3) uptake was reduced by 0, 24, and 36%, respectively, from that expected if there had been no decline in g(wv). With increasing total O(3) exposure, A declined, but the reduction was not strictly cumulative, i.e., A measured on Days 49 and 70 was similar for a given treatment even though both total O(3) exposure and uptake had increased. At the end of the experiment, A at near saturating CO(2) (1000 micro mol mol(-1)) and saturating photosynthetic photon flux density was reduced by about 25, 40 and 50% in seedlings in the Low-O(3), Low/High-O(3) and High-O(3) treatments, respectively, compared to the control seedlings. The ratio of internal to external CO(2) concentrations, an indicator of relative change in stomatal limitation of A, did not change over time and did not differ among treatments, suggesting that A and g(wv) decreased in parallel. After 40-60 days without O(3), A of seedlings in all O(3) treatments was not significantly different. Our data indicate that O(3)-induced stomatal closure was a result of reduced A and that decreased g(wv) reduced O(3) uptake to a rate that needles of ponderosa pine could tolerate without exhibiting further reductions in gas exchange capacity.     

Diversity and surge in abundance of native parasitoid communities prior to the onset of Torymus sinensis on the Asian chestnut gall wasp(Dryocosmus kuriphilus) in Slovenia,Croatia and Hungary

Since the rapid spread of the Asian chestnut gall wasp(ACGW) throughout south-east Europe in the last few years,the possibilities of its control have been increasingly investigated.Due to constraints in available suppression measures in forest stands,biological control is recognized as the most suitable action to lower the abundance of the new invasive pest.Torymus sinensis,as a specialized parasitoid chalcid wasp of ACGW,was introduced to suppress the pest in Italy in 2005,and later in Croatia,Hungary(2014) and Slovenia(2015).We investigated the native parasitoid complex associated with ACGW in Slovenia,Croatia and Hungary over 8 years of sampling.We found 41 species of native parasitoids,eight of which are the first records on ACGW in Europe,adding up to a total of 51 species known to parasitize ACGW.These findings represent a large complex of cynipid-parasitoid fauna.Moreover,the abundance of native parasitoid populations on ACGW have demonstrated a temporal surge between the invasion of a new alien host(ACGW) and the onset of its specialized parasitoid,T.sinensis.Our results indicate that the introduced parasitoid acts as a very successful biocontrol of ACGW,outcompeting native parasitoids.This outcome should be considered as beneficial through the maintenance of ecological balance in affected forest ecosystems.     

1-(3-Hydroxy-4-methoxy-5-methylphenyl) ethanone, a new compound from the stem bark of Lamprothamnus zanguebaricus

The chloroform extract of the stem bark of Lamprothamnus zanguebaricus has yielded two ethanones; 1-(3-hydroxy-4-methoxy-5-methylphenyl)ethanone (I) (a new compound) and 1-(3-hydroxy-4-methoxyphenyl)ethanone (II). The structures of both compounds were established by spectroscopic methods.     

Spatial analysis and structure of a cross-timber stand in the TallGrass Prairie Preserve (Pawhuska, Oklahoma)

I analyzed the spatial distribution and structure of trees in a cross timber forest in the Tallgrass Prairie Preserve (Pawhuska, Oklahoma, USA). I mapped and measured diameter of all stems, saplings (>1.5m tall) and dead trees in a 4-ha plot. The stand was dominated by Quercus stellata and Q. marilandica. In total, I mapped 7,636 trees, consisting of 6,785 Q. stellata, 846 Q. marilandica, 2 Celtis occidentalis, 1 Fraxinus pensilvanica and 2 Prunus americana. For saplings, I mapped 54 Q. stellata and 21 Q. marilandica. The size class distribution of the two dominant species did not differ. The dominant mortality class was "standing dead", while I only found saplings less than 2 m tall. The spatial distribution of the species indicated segregation in the use of the environment, generating a clumped univariate distribution of stems of the same species within radii of 30m, but repulsion outside 30m. This segregation can be explained by the different ecological requirements of each species.