马尾松毛虫对马尾松和湿地松的选择与适应研究

用马尾松老叶、新叶,湿地松老叶、新叶,当年生马尾松新叶、湿地松新叶和当年生以20％和40％β-蒎烯处理过的马尾松新叶作食料饲养马尾松毛虫。结果表明：马尾松毛虫幼虫在第1代发生期取食马尾松老叶、马尾松新叶、湿地松老叶和湿地松新叶等4种不同质量的食料后,因其食料中10种必需氨基酸含量和挥发性物质β-蒎烯含量的不同,导致幼虫的存活率差异显著。其中,取食马尾松老叶的幼虫成活率最高（44％）,依次为马尾松新叶（32.7％）、湿地松老叶（4％）,而取食湿地松新叶的幼虫全部死亡。通过马尾松针叶增加外援β-蒎烯喂养马尾松毛虫实验,表明增加了外源β-蒎烯的松针饲养的马尾松毛虫幼虫与用同样松针未增加外源β-蒎烯饲养的幼虫相比,死亡率明显提高;松树中β-蒎烯含量的增加与幼虫成活率呈显著负相关。由此,我们阐明了马尾松与湿地松对马尾松毛虫的抗虫机制。     

Changes in Peroxidase Activity Associated with Cell Walls During Pine Hypocotyl Growth

Peroxidase active against 2,2'-azino-bis-[3-ethylbenzthiazoline-6-sulphonicacid] (ABTS) and guaiacol were found in the apoplastic fluid,as well as ionically and covalently associated with pine cellwalls. The highest activity was found covalently bound to cellwalls, while the lowest activity was in the apoplastic fluid.Both ABTS and guaiacol peroxidases increased with the hypocotylage in the three fractions, apoplastic, ionically and covalentlybound. Furthermore, the changes in both peroxidases along thehypocotyl were also studied. Both apoplastic ABTS- and guaiacol-peroxidasesincreased from the apical towards the basal region of the hypocotylsof 10-d-old seedlings. A relation between peroxidase activityin the apoplastic fluid and the cell wall stiffening in pinehypocotyls is proposed.Copyright 1995, 1999 Academic Press Cell wall, growth, hypocotyl, peroxidase, pine, Pinus pinaster Aiton     

Ethylene production by different age class ponderosa and Jeffery pine needles as related to ozone exposure and visible injury

Summary Ethylene produced by different needle age classes representing natural populations of two ponderosa pine varieties [Pinus ponderosa var. arizonica (Engelm.) Shaw and var. ponderosa Dougl. ex Laws.] and Jeffery pine (Pinus jeffreyi Grev. and Balf.) was characterized using mercuric perchlorate traps. All populations contained individual trees which were either symptomatic or asymptomatic with respect to visible ozone injury. Ethylene production by different needle age classes was also characterized in P. ponderosa var. ponderosa seedlings grown in open top ozone fumigation chambers. Older age class needles produce significantly (P>0.05) more ethylene than younger age class needles. Needles of both P. ponderosa var. ponderosa and P. jeffreyi exhibiting ozone injury in the field produced significantly (P>0.05) higher levels of ethylene than asymptomatic conspecific trees. Seedlings exposed to the highest level of ozone in the fumigation study produced the highest levels of ethylene, followed by fumigation with medium and low ozone concentrations and carbon filtered air. These data indicate that the measurement of ethylene in conifer needles, as a measure of stress, needs to be calibrated for needle age class. It also suggests that the sensitivity of a tree to ozone injury may be regulated by the inherent ability of the individual to produce ethylene.     

Growth and Nutrient Retranslocation in Needles of Radiata Pine in Relation to Nitrogen Supply

The effects of N application on tree growth and the retranslocationof N, P, and K from young needles to new growth were examinedin young radiata pine (Pinus radiata D. Don) trees. Nitrogen fertilization increased the number and size of needles,rates of shoot production, stem volume growth and tree biomass.Foliar N and P contents (µg per needle) fluctuated ina cyclic fashion with prominent phases of accumulation, retranslocationand replenishment. The patterns of these fluctuations in controland N-fertilized trees were similar, although the fluxes ofN, P and K in and out of needles were increased by N fertilization.Greater translocation (g per tree) of N and K from needles ofN fertilized trees occurred because fertilization increasedthe needle weight and the proportion of N and K retranslocatedfrom individual needles. Nitrogen fertilization increased theretranslocation of P largely as a result of higher needle mass.Trees supplied with more than adequate amounts of P in the soilretranslocated up to 58 per cent of the initial pool of P fromyoung needles. The periods of high retranslocation coincidedwith periods of high concentrations of soil mineral N and withshoot production. Conversely, the periods of rapid replenishmentof N and P into the needles coincided with the time of slowshoot growth and low concentration of soil mineral N. The growthrate of trees, rather than the availability of nutrients inthe soil was the main factor controlling retranslocation. For radiata pine, retranslocation from needles is not a mechanismspecific for coping with low soil fertility. It seems to bea mechanism which enhances the nutrient supply to apical growingpoints, especially during periods of flushing. Pinus radiata, nitrogen supply, shoot growth, nutrient fluctuations and retranslocation, nutrient use and adaptation     

Assay and Electrophoresis of Superoxide Dismutase from Red Spruce (Picea rubens Sarg.), Loblolly Pine (Pinus taeda L.), and Scotch Pine (Pinus sylvestris L.) : A Method for Biomonitoring

This paper reports a method for extracting the antioxidant enzyme superoxide dismutase (SOD) from the needles of red spruce (Picea rubens Sarg.), loblolly pine (Pinus taeda L.), and scotch pine (Pinus sylvestris L.) with high efficiency and free from interfering compounds. The extraction employs phosphate buffer with polyvinylpolypyrrolidone and Triton X-100 followed by dialysis overnight. The isozymes of SOD in each species were separated electrophoretically and tested for their sensitivity to KCN and H₂O₂. An isozyme resistant to these inhibitors was found in the spruce but not the pine needles. The isozymes from the spruce needles were examined for individual responses to aging and H₂O₂ inhibition. Four of the five CuZn isozymes in spruce were found to have increased significantly but equally by October of their first year and two of those four isozymes were found to be more sensitive to H₂O₂. The response of the SOD isozymes in loblolly pine seedlings to O₃ was also examined and the isozymes were found to be induced equally. Because the SOD activity in the young pine needles was too low to electrophorese, the SOD activity from the pines in the O₃ experiment had to be partially purified using CHCl₃ and ethanol, then concentrated.     

Neodiprion sertifer defoliation causes long-term systemic changes of oxidative enzyme activities in Scots pine needles

The aim of the experiments reported here was to study possible long-term effects of Neodiprion sertifer Geoff. (Hymenoptera: Diprionidae) herbivory, or artificial defoliation, on oxidative enzyme activities in Scots pine (Pinus sylvestris L.) needles as a consequence of induced defense responses. During year 1 (the first season), defoliation by N. sertifer, which feeds on previous season’s needles, did not result in statistically significant changes in polyphenol oxidase activity in the current year’s needles. In contrast, defoliation did lead to increased peroxidase activity in those needles. In the second season (year 2) N. sertifer defoliation of pine seedlings, also defoliated in the previous season either by larvae or artificially, resulted in a decrease of peroxidase activity in the current year’s needles. No significant differences between treatments carried out in year 1 were found in year 2 for peroxidase activity in the previous year’s needles. However, defoliation in year 1 by N. sertifer resulted in decreased needle consumption, and higher mortality of larvae, in year two. These results indicate the existence of long-term changes in needle oxidative enzyme activities as a consequence of N. sertifer feeding.     

Structure of the Needles in the Early Phases of Development in Pinus ponderosa P. et C. Lawson with Special Reference to Plastids

Before they emerged from the fascicular sheath, the tissuesof young needles of Pinus ponderosa P. et C. Lawson alreadyshowed some characteristics typical of mature needles. The organelles,particularly the plastids, had undergone different development.The plastids in different types of cell varied in their ultrastructureand in association with the endoplasmic reticulum (ER). A sheathof ER was observed around the amoeboid plastids in epidermalcells, epithelial cells of resin ducts and maturing transfusiontracheids whereas there was no ER sheath around the young mesophyllchloroplasts, the fusiform chloroplasts in some transfusiontracheids and the proplastids in xylem and phloem cells. Thecontent of chlorophyll (a+b) was 0·85 g kg^-1 dry matterand chlorophyll a/b ratio was 2·70. The needles may becomephotosynthetically active whilst still within the fascicularsheaths.Copyright 1993, 1999 Academic Press Pinus ponderosa, ponderosa pine, needle structure, needle ontogeny, plastids, endoplasmic reticulum     

Accumulation of Phenolic Compounds in the Necrotic Areas of Austrian and Red Pine Needles Due to Salt Spray

Austrian pine (Pinus nigra) and red pine (P resinosa) were testedfor needle damage caused by salt spray. Morphology and histologyof newly grown needles were compared in 3- and 6-year-old plantsgrowing in the greenhouse under controlled conditions. Pottedplants covered with plastic bags were sprayed daily either withdistilled H₂O or saturated salt solution. Needle tips, mid-partsand bases were fixed after 1, 3 and 24 h, and 3, 7 and 30 din glutaraldehyde+0·1 % caffeine for precipitation ofphenolics. Histochemical reactions and electron microscope observationsshowed that the morphological damage is linked to increasedphenolic compound deposition in mesophyll cells, beginning directlyunder the stomata. Disorganization of membranes leads to deathof the mesophyll cells, even before morphological damage isrecognizable as brown spots on the needle surface. Thus thehistochemical reactions and observations of cell structure revealeddamage earlier than macroscopic observations. Salt injury, phenolic compounds, histological damage, ultrastructural damage, salt spray, Pinus nigra, Austrian pine, Pinus resinosa, red pine     

Fine Root Productivity and Turnover in Two Evergreen Central Himalayan Forests

Fine root production and mortality in central Himalayan evergreenforests consisting of Quercus leucotrichophora (banj oak) andPinus roxburghii (chir pine) were measured. Fine root productionand mortality decreased with increasing soil depth. Annual fineroot production was higher in the broadleafed forest than inthe coniferous forest, across months and seasons (1.3 and 1.5-timesmore living and dead root biomass, respectively in banj oakthan in chir pine). Live fine root production was 2508 kg ha^-1year^-1inchir pine forest and 3631 kg ha^-1year^-1in banj oak forest. Deadfine roots accumulated at a rate of 1197 and 1525 kg ha^-1year^-1inchir pine and in banj oak forest, respectively. In both forests,the greatest fine root production was recorded in the rainyseason followed by summer and winter seasons. Both soil androot nitrogen concentration decreased with increasing soil depth.Nitrogen uptake was higher in banj oak forest (12.1 kg ha^-1year^-1)than chir pine forest (7.2 kg ha^-1year^-1).Copyright 1999 Annalsof Botany Company Fine root production, fine roots, necromass, banj oak, chir pine, Quercus leucotrichophora , Pinus roxburghii .     

The uptake of and structural changes induced by trichloroacetic acid in the needles of Scots pine seedlings

The uptake of trichloroacetic acid (TCA) and structural changesinduced in the needles of Scots pine (Pinus sylvestris L.) seedlingswere studied. Two exposure set-ups, a root route and an atmosphericroute through the surfaces simulating the wet deposition offog, were used. Both set-ups included two dose levels and correspondingcontrol treatments. The temperature and the relative humidityin the climate chambers were adjusted to represent the conditionsof June–July in a subarctic area in central Finland. Theseedlings were exposed three times a week for two months. Theresults showed that the uptake of TCA in needles occurred bothvia roots and via needle surface. However, most of the TCA viathe atmospheric route was absorbed on the surface of the needles.The structural responses in pine needles depended partly onthe treatment method: TCA applied via the atmospheric routedisintegrated the structures of the epicuticular waxes and thatof the stomatal cells, which was not seen in the exposures viaroots. A common feature was the decrease in size of the chloroplastsin concert with the increasing TCA concentrations inside theneedles. Key words: Pinus sylvestris L., climate chamber, effects, microscopic structure, secondary pollutant, TCA, trichloroacetic acid     

Transport of 14C-labelled Assimilates and 32P-labelled Phosphate in Salix viminalis in Relation to Phyllotaxis and Leaf Age

Autoradiographic techniques have been used to investigate thetransport of ¹⁴C-assimilates and ³²P-phosphate in relation tophyllotaxis and age of leaves in Salix viminalis. The leavesborne on the young shoots of S. viminalis are arranged in fiveorthostichies. Three of these orthostichies share one main transportchannel, a second channel being shared by the leaves on theremaining two orthostichies. Where two orthostichies are separatedby an angular distance of 72°, transport may occur betweenleaves on these orthostichies. In addition to the phyllotaxis of the leafy shoot, it has beendemonstrated that the age of the leaf is a factor which determinesthe distribution of materials between leaves.     

Growth Analysis of Perennial Plants: The Relative Production Rate and its Yield Components

A new formulation for plant growth analysis, called the relativeproduction rate, is proposed for use in the study of perennialplants. The new measure and its yield components are similarto current growth analysis, but use the annual increment ofgrowth, rather than total accumulated growth, as the basis forassessing performance. The relative production rate removesaccumulated past growth of the perennating structure, a majordeterminant of relative growth rate, and acts independentlyof tree size as a measure of the vigour of growth. The multiplicativeyield components of this relative production rate also providebetter insight into the current morphological and physiologicalfeatures of the tree than the standard growth analysis formulations.Examples are given using Douglas-fir (Pseudotsuga menziesii(Mirb.) Franco) and red pine (Pinus resinosa Ait.) plantationsto illustrate the methodology proposed. Pseudotsuga menziesii (Mirb.) Franco, Pinus resinosa Ait., Douglas-fir, red pine, growth analysis, relative production rate, tree development, competition     

The Ultrastructure of the Host-parasite Interface in the Needles of Pinus nigra Infected with Lophodermella sulcigena

The hyphae of Lophodermella sulcigena are usually surroundedby an electron-opaque matrix when growing in the needles ofCorsican pine (Pinus nigra var. maritima). The host-parasiteinterface is of a type which has been little studied; the intercellularhyphae kill the mesophyll cells of the host ahead of themselvesand their walls are separated from those of the host by a matrix.The first signs of injury to the host are disorganized membranesystems, particularly the thylakoid and bounding membranes ofthe chloroplasts break down. The dead host cells are filledwith resin or tannin in which only the starch grains are visible.     

Water relations, xylem embolism and histological features of Pinus thunbergii inoculated with virulent or avirulent pine wood nematode, Bursaphelenchus xylophilus

The development process of pine wilt disease caused by Bursaphelenchusxylophilus (Steiner and Buhrer) Nickle, pine wood nematode,was studied ecophysiologically and histologically in relationto pathogenicity of B. xylophilus. Judging from the predawnxylem pressure potential of needles, the heat pulse velocity,and the soil water potential, the control Pinus thunbergii Parl.,used for the study, was not water-stressed. Virulent B. xylophilusisolate can kill non-waterstressed pines. In virulent B. xylophilusisolateinoculated pines, the predawn xylem pressure potentialof needles abruptly decreased when the colour of 1-year-oldneedles changed to brown and then the water conducting functionof the xylem was lost completely. Avirulent B. xylophilus isolatedoes not affect the needle colour and the xylem pressure potentialof pines. Avirulent B. xylophilus isolate-inoculated pines,however, responded to nematode invasion by decreasing hydraulicconductance of stem and root xylems. In addition, oleoresinexudation slightly decreased. The decreased hydraulic conductanceresults from embolism of tracheids caused by cavitation in thecentral part of the xylem. From histological observation, allof the parenchyma cells in virulent B. xylophilus isolateinoculatedpines died. In contrast, the parenchyma cells, degenerated inavirulent B. xylophilus isolateinoculated pines, were limitedin the embolized region of the xylem. The difference betweenthe response of pine to the virulent B. xylophilus isolate invasionand that to avirulent B. xylophilus isolate invasion indicatesthat nematode-induced death of pine relates to the death ofparenchyma cells, as well as the decrease in xylem hydraulicconductance. Key words: Embolism, hydraulic conductance, parenchyma cells, pathogenicity of pine wood nematode, pine wilt disease.     

Electron Microscopy of the Epidermis and Cuticle of the Needles of Pinus nigra var. maritima in relation to infection by Lophodermella sulcigena

Changes in the ultrastructure of the epidermis and cuticle ofCorsican pine (Pinus nigra var. maritima (Aiton) Melville) inrelation to infection of the needle by Lophodermella sulcigena(Rostr.) v Hohn were recorded throughout a growing season. Epidermalcells when young had thin walls and a thin smooth cuticle: bothstructures thickened with age, and the needle surface becamerough. Densely packed wax tubes developed around the stomatalpore and later became scattered over the needle surface. Themicro-flora present on the needles is briefly noted. Changesin the structure and micro-flora of needles as they aged arethought to contribute to the confinement of infection by L.sulcigena to the needle bases.     

Movement of Nutrients in Radiata Pine Needles in Relation to the Growth of Shoots

The pattern of needle growth and the movement of mineral nutrients(nitrogen, phosphorus, potassium and calcium) in needles ofradiata pine (Pinus radiata D. Don) were studied from needleinitiation to 2 years of age. During this period, very prominentcyclic patterns of nutrient accumulation, retranslocation andreplenishment were observed for nitrogen, phosphorus and potassium,which highlighted the potential role of needles as a nutrientreserve for growth. Significant retranslocation occurred from very young needlesabout 3 months after initiation. The phases of retranslocationcoincided with new flushes of shoot growth, and the growth ofnew shoots on a branch resulted in nutrient withdrawal frompre-existing needles, regardless of needle age and season. Suchwithdrawal occurred even in fertilized and irrigated trees onhigh quality sites and under environmental conditions conducivefor nutrient uptake. At all times, except for the short periodafter initiation when needles were actively growing, the nutrientsin the needle were readily available for retranslocation. Contraryto the general view, retranslocation of nutrients was not necessarilyrelated to senescence and ageing of needles. Because new shoots are the primary ‘sinks’ for retranslocatednutrients, an ongoing competition between different parts ofa branch for internal nutrients can be envisaged, preferencebeing for the youngest shoot in the hierarchy. The relevanceof these results to our understanding of ‘optimum nutrition’of pine trees is discussed. Pinus radiata D. Don, radiata pine, mineral nutrition, retranslocation, phosphorus, nitrogen, shoot growth     

A Comparison of the Seasonal Rates of Dry Matter Production of Three Coniferous Species with Contrasting Patterns of Growth

Seasonal rates of growth and dry-matter production were examinedin second-year seedlings of Larix leptolepis, Pinus contorta,and Pinus radiata grown in an unheated glasshouse. The deciduousLarix had a higher rate of production of dry matter than eitherof the two species of Pinus until the time of leaf fall, andthis was accompanied by a greater height and diameter increment.However, between the time of leaf fall in Larix and the endof the growing season, the species of Pinus increased in dryweight by more than 25 per cent, and in consequence Larix, becauseof its deciduous habit, lost much of the advantage of its fastgrowth-rate. Comparison of the two pine species showed thatP. radiata, while making nearly 3.5 times as much height incrementas P. contorta, had only a 45 per cent higher dry weight thanthat species at the end of the experiment. The dry-weight differenceswere due to differences in relative growth-rate (RGR). The RGR differences between the two pine species resulted fromdifferences in net assimilation rate (NAR) rather than differencesin the ratio of photosynthetic to non-photosynthetic tissue,and P. radiata gained most of its dry-weight advantage duringthe two months of October and November. It seems possible thatthe higher NAR of P. radiata at this time was a reflection ofthe difference in growth habit between the two pine species,and possible mechanisms by which growth may have affected NARin this experiment are briefly considered.     

Indirect Measurement of Pore Size and Permeability in Scots Pine and Norway Spruce

Five experiments to investigate the water relationships of Scotspine and Norway spruce sapwood are described. Field exposureof stakes, and their moisture characteristic relating wood moisturecontent to the water potential of the surroundings showed thatspruce had a lower moisture content than pine under the sameconditions. A pore size distribution derived from the characteristicsshowed more large pores in spruce than in pine, but in sprucethere were also more small pores. The inference was that thelarge pores of spruce were readily accessible to water, allowinga fast rate of water uptake, as found in the wick action andswelling investigations, while the small pores were not accessible,resulting in a low rate of water uptake and a low rate of swelling.The possibility is briefly discussed that it is the pore sizedistribution of the two woods which determines their water relationships,and the difference in pore size which determines their treatability. Key words: Pinus sylvestris L, Picea abies (L) Karst, Pore size, Water uptake     

Changes of 1-Aminocyclopropane-1-Carboxylic Acid Oxidase Activity in Stressed Pinus Sylvestris Needles

Stimulation of ethylene biosynthesis in pine needles by hydrogen peroxide and sodium bisulfite coincided with the activation of ACC oxidase at the level of protein synthesis. Decrease in ethylene production at high concentrations of sodium bisulfite (above 7 mM) was apparently due to inhibition of ACC oxidase activity. Treatment of pine needles with aminotriazole caused an inhibition of both ethylene production and ACC oxidase activity. Both methylviologen and methyl jasmonate stimulated ACC oxidase activity in a concentration-dependent manner with no parallel changes in ethylene production. The presented results suggest that ACC oxidase plays an important role in regulation of ethylene formation in pine needles in response to different stimuli.     

Structure, Production and Leaf Area Dynamics: A Comparison of Lodgepole Pine and Sunflower

Populations of lodgepole pine (Pinus contorta var latifoliaEngelm) and sunflower (Heltanthus annuus L) were examined tocompare the influence of stand density on canopy structure andthe association between canopy structure and the productionof stem volume The plastic responses of canopy structure tocompetitive interactions indicated that the structural dynamicsof lodgepole pine and sunflower populations were similar, thoughthe degree of plastic response differed The influence of canopystructure on the production of stem volume, however, was fundamentallydifferent efficiency decreased as the mean crown size of lodgepolepine populations increased, but this decrease did not occurin sunflower populations This difference was attributed to thelarge accumulation of branch biomass required to display foliageeffectively in the canopies of the perennial lodgepole pine,accumulation which does not occur in the annual sunflower Lodgepole pine, Pinus contorta var latifolia Engelm, sunflower, Helianthus annuus L, leaf area, canopy structure, stand production, carbon allocation