SEASONAL TRENDS IN RATES OF PHOTOSYNTHESIS AND RESPIRATION OF LOBLOLLY PINE AND WHITE PINE SEEDLINGS

Mc Gregor , William H. Davis (Clemson Coll., Clemson, S.C.), and Paul J. Kramer . Seasonal trends in rates of photosynthesis and respiration of loblolly pine and white pine seedlings. Amer. Jour. Bot. 50(8): 760–765. Illus. 1963.—Seasonal trends in the rates of photosynthesis and respiration of potted loblolly and white pine seedlings were studied by measuring CO₂ exchange with an infra-red gas analyzer at intervals during a year. The seedlings were kept out-of-doors, but measurements were made indoors at 25 C and 4000 ft-c of light. Beginning in February, the rate of photosynthesis per plant of both species increased, reaching a peak in mid-September for loblolly pine and in mid-July for white pine and then declining rapidly after mid-September for both species. The spring increase began before new needles emerged and the autumn decline was not accompanied by appreciable loss of foliage. The respiration rate of loblolly pine increased steadily throughout the year. Respiration of white pine increased until mid-May and then remained fairly constant through the remainder of the year. Maximum rate of photosynthesis per unit of fascicle length occurred in July for the white pine and in May for the loblolly pine, and rates declined after September in both species. Respiration rate per unit of fascicle length showed a marked increase as spring growth began in April, then decreased to a minimum in September and increased during the winter in both species. Total chlorophyll per seedling reached a maximum in September for both species and declined slightly during winter. Total chlorophyll per unit of fascicle length increased in the spring, declined slightly in midseason, and increased again in September. Photosynthesis per unit of chlorophyll reached a maximum in May for loblolly pine and in July for white pine. Stem elongation of white pine was 88% completed by May 15. On the same date, stem elongation of loblolly pine was only 42% completed.     

The Antioxidant Activity of Copper(II) (3,5-Diisopropyl Salicylate)4 and Its Protective Effect Against Streptozotocin-Induced Diabetes Mellitus in Rats

Oxidative stress has been suggested as a potential contributor to the development of diabetic complications. In this study, we investigated the protective effect of a strong antioxidant copper complex against streptozotocin (STZ)-induced diabetes in animals. Out of four copper complexes used, copper(II) (3,5-diisopropyl salicylate)₄ (Cu(II)DIPS) was found to be the most potent antioxidant–copper complex. Pretreatment with Cu(II)DIPS (5 mg/kg) twice a week prior to the injection of streptozotocin (50 mg/kg) has reduced the level of hyperglycemia by 34 % and the mortality rate by 29 %. Injection of the same dosage of the ligand 3,5-diisopropyl salicylate has no effect on streptozotocin-induced hyperglycemia. The same copper complex has neither hypoglycemic activity when injected in normal rats nor antidiabetic activity when injected in STZ-induced diabetic rats. The protective effect of Cu(II)DIPS could be related to its strong antioxidant activity compared to other copper complexes median effective concentration (MEC)?=?23.84 μg/ml and to Trolox MEC?=?29.30 μg/ml. In addition, it reduced serum 8-hydroxy-2′-deoxyguanosine, a biomarker of oxidative DNA damage, by 29 %. This effect may explain why it was not effective against diabetic rats, when β Langerhans cells were already destroyed. Similar protective activities were reported by other antioxidants like Trolox.     

Nursery Culture Impacts Cold Hardiness in Longleaf Pine (Pinus palustris) Seedlings

Success in restoring longleaf pine ecosystems depends on outplanting high‐quality longleaf pine seedlings. One important and relatively understudied attribute of seedling quality is cold hardiness. A suite of trials was conducted to investigate the influence of common nursery cultural practices on longleaf pine cold hardiness. Cold hardiness was increased with higher rates of nitrogen, unaffected by copper coating containers, greater for foliage than for root‐collar tissue, and tended to increase with increases in container size.     

Effect of Copper Sulfate and Lead Acetate on Infection of Pines with Bursaphelenchus xylophilus

Treatment of 3-year-old Scots, white, and Austrian pine seedlings with copper sulfate or lead acetate significantly affected energy homeostasis and oleoresin production in the seedlings but did not induce wilting of the seedlings. Inoculation of copper sulfate-treated or lead acetate-treated white, Scots, and Austrian pine seedlings with the white pine specific pathotype of Bursaphelenchus xylophilus, VPSt-1, caused a significant increase in oleoresin production, stressed energy homeostasis, and induced rapid wilting of the seedlings. Scots pine lost tolerance and Austrian pine lost resistance to VPSt-1 after the seedlings were treated with either copper sulfate or lead acetate. These results suggest that environmental pollution may significantly affect susceptibility of pines to B. xylophilus and may have a role in establishment of this nematode in uninfested areas.     

The chemical composition of pine foliage in relation to the population dynamics of the pine beauty moth,Panolis flammea,in Scotland

Summary This paper reports part of a study to determine why damaging outbreaks of the pine beauty moth, Panolis flammea (D & S) (Lepidoptera: Noctuidae), in Scotland are frequent on lodgepole pine but do not occur on Scots pine, and why outbreaks on lodgepole pine are mainly confined to trees growing in deep unflushed peat. The elongation of shoots and the growth of needles of Scots pine occurred later in the season than did those of lodgepole pine. The foliage of Scots pine generally had a higher level of nitrogen, and consistently had a higher level of phosporus, but had a consistently lower level of tannins than that of lodgepole pine during the period when the larvae were feeding each year. The nitrogen content of the foliage of lodgepole pine growing in an iron pan soil was generally higher than that of lodgepole pine growing in deep peat during the same period but there were no general differences in the phosphorus or tannin contents of lodgepole pine in the 2 soil types. These findings suggest that Scots pine is a more suitable host plant than lodgepole pine and that the foliage of lodgepole pine growing in deep peat is not more suitable than lodgepole pine growing in an iron pan soil. On the basis of the chemical analyses used in this study, it is concluded that the abundance of pine beauty moth in Scotland is not strongly influenced by the nutritional suitability of its host plants.     

Induction of C-reactive protein, serum amyloid P component, and kininogens in the submandibular and lacrimal glands of rats with experimentally induced inflammation.

The mRNAs for acute-phase proteins and kininogens were found to be increased in the submandibular gland (SMG) and extraorbital and intraorbital lacrimal gland (ELG and ILG) in response to experimentally induced inflammation in rats; i.e., 24 hours after subcutaneous injection of turpentine oil, mRNAs for C-reactive protein (CRP), serum amyloid P component (SAP), and H- and T-kininogens were induced in the SMG, ELG, and ILG of rats, whereas these mRNAs were not detected in the same tissues of normal control rats. The induction of mRNAs for these inflammatory proteins by turpentine oil was preceded by a transient increase in the level of mRNA for tumor necrosis factor-alpha (TNF-alpha) at 6 hours after subcutaneous injection of the oil. This was confirmed by injection of another inflammation inducer, lipopolysaccharide (LPS), which induced the TNF-alpha mRNA in the same way at 6 hours as turpentine oil did. The up-regulation of acute-phase proteins including kininogens in the SMG, ELG, and ILG suggest the existence of a strict defense system in the exocrine glands.     

A Comparison of Phenolic Constituents of Pinus monticola Resistant and Susceptible to Cronartium ribicola

Polyphenols and simple phenols in Pinus monticola Dougl. foliage and hark were studied in relation to host resistance to Cronartium ribicola J. C. Fisch. ex Rabenh. More than 50 phenolic substances were detected but no qualitative differences were found between resistant and susceptible trees. Some evidence is given for a quantitative relationship between one polyphenol in white pine foliage and resistance to blister rust. This compound may be a guaiacyl derivative. Differences in phenolics due to tree-to-tree variation, needle age, tissue (foliage versus bark), and season of year are also reported.     

Synthesis, crystal structure, EPR properties, and anti-convulsant activities of binuclear and mononuclear 1,10-phenanthroline and salicylate ternary copper(II) complexes

Two ternary Cu(II) complexes of 1,10-phenanthroline (phen) and singly (Hsal(-)) or dideprotonated (sal(2-)) salicylate ligands were synthesized, their X-ray crystal structure and electron paramagnetic resonance spectral characteristics determined, and evaluated for anti-convulsant activities in the maximal electroshock (MES) and Metrazol models of seizure and Rotorod toxicity. The X-ray crystal structure of [bis(1,10-phenanthroline)-mu-bis(salicylato-O,O')dicopper(II)] dihydrate, 1, ([Cu(II)(2)(phen)(2)(sal)(2)].2[H(2)O]), shows it to be binuclear. This dimer consists of two centrosymmetrically related pseudo-five coordinate Cu(II) atoms 3.242(2) A apart and bridged by two dideprotonated salicylate ligands. The X-ray crystal structure of [bis(1,10-phenanthroline)(salicylato)copper(II)][salicylate] monohydrate, 2, ([Cu(II)(phen)(2)(Hsal)](+)[Hsal](-)[H(2)O]), shows it to be mononuclear. This complex cation exhibits a highly irregular distorted square pyramidal geometry about the Cu(II) atom, (4+1+1*). Each salicylate is singly deprotonated and one of them is ligand bonded in an asymmetric chelating mode. EPR results for 2 indicate that in concentrated DMF solution phen remains bonded to copper but salicylate is likely monodentate in contrast to the situation for 1. However, in dilute DMF solution, both 1 and 2 form the same species, which accounts for the similarity in anti-convulsant activity of the two compounds. Both 1 and 2 were found to be effective in preventing MES-induced seizures and ineffective in preventing Metrazol-induced seizures. Rotorod toxicity, consistent with central nervous system depression, paralleled the observed anti-convulsant activity. It is suggested that the observed anti-convulsant activity is consistent with central nervous system depression as a physiological mechanism in overcoming MES-induced seizures due to MES-induced brain inflammatory disease.     

Adult parasitoids of the southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae), feed on artificial diet on pine boles, pine canopy foliage and understory hardwood foliage

This study examined adult parasitoids of Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae) utilizing an artificial parasitoid food on locations with and without hosts. Eliminade™ was applied to bark on boles of infested pines, to pine canopy foliage and to understory hardwood foliage. Adult parasitoids were collected, identified and dissected to determine the presence of Eliminade™ within their guts. Individuals from eight parasitoid species were collected on pine boles within D. frontalis infestations in the Talladega National Forest (Alabama) in the summer of 1999 and 2000. Mean percentage of parasitoids feeding on Eliminade™ was 62±10% during both summers. Percentage of parasitoids feeding was the same 24 h after Eliminade™ application, regardless of food location or parasitoid species. Seven days later, level of parasitoid feeding on Eliminade™ was insignificant in the pine canopy and hardwood understory. In contrast, percent of parasitoid feeding on Eliminade™ applied to pine boles remained the same between 1 and 7 days of the application. Therefore, not only will adult parasitoids visit and feed on artificial food on pine boles with hosts, but also non-host locations such as pine canopy and understory hardwood foliage. These results have implications for potential sources of adult nutrition for parasitoids of D. frontalis.     

Decline and Death of Pinus spp. in Delaware Caused by Bursaphelenchus xylophilus

Etiological studies to determine the cause of decline and death of Pinus spp. in Delaware were initiated in 1980. The pinewood nematode, Bursaphelenchus xylophilus, was found to be the major canse of mortality in Japanese black pine (Pinus thunbergii). When inoculated into healthy 5-yr-old Japanese black pines, B. xylophilus produced typical decline symptoms observed in the field. The xylophilous fungi most often associated with declining trees, Rhizosphaera pini, Fusarium spp., and Pestalotia funerea, were not pathogenic to Japanese black pine in greenhouse tests. Mineral analyses of soil and foliage showed no significant differences between healthy and infested trees. B. xylolyhilus was also found on loblolly pine (P. taeda), scrub pine (P. virginiana), Scots pine (P. sylvestris), red pine (P. resinosa), Eastern white pine (P. strobus), and pitch pine (P. rigida).     

Micronutrient composition of xylem sap and needles as a result of P-fertilization in maritime pine

Xylem sap and foliar compositions (P, Cu, Zn, Mn) were examined over 4 months in control and P-fertilized maritime pine in a 7-year-old plantation. The absorption of copper, zinc, and boron appears to be reduced by phosphate fertilization. Manganese concentrations are positively related to P-supply increase. Foliar analysis and sap provides the same type of information in terms of antagonism or synergism between elements but the response to treatment is more often significant with sap throughout the seasons and is completely non-existent on a single classical autumn diagnosis with foliar concentration (i.e. Zn and Cu). In consequence foliar analysis is not sensitive enough for copper or zinc deficiency diagnoses in young plantations where nutritional growth disorders appear in a short period of spring, and xylem chemistry appears to be a convenient tool in monitoring micronutrient disorders in pine plantations.     

RNAi‐mediated Ultra‐low gossypol cottonseed trait: performance of transgenic lines under field conditions

Cottonseed remains a low‐value by‐product of lint production mainly due to the presence of toxic gossypol that makes it unfit for monogastrics. Ultra‐low gossypol cottonseed (ULGCS) lines were developed using RNAi knockdown of δ‐cadinene synthase gene(s) in Gossypium hirsutum. The purpose of the current study was to assess the stability and specificity of the ULGCS trait and evaluate the agronomic performance of the transgenic lines. Trials conducted over a period of 3 years show that the ULGCS trait was stable under field conditions and the foliage/floral organs of transgenic lines contained wild‐type levels of gossypol and related terpenoids. Although it was a relatively small‐scale study, we did not observe any negative effects on either the yield or quality of the fibre and seed in the transgenic lines compared with the nontransgenic parental plants. Compositional analysis was performed on the seeds obtained from plants grown in the field during 2009. As expected, the major difference between the ULGCS and wild‐type cottonseeds was in terms of their gossypol levels. With the exception of oil content, the composition of ULGCS was similar to that of nontransgenic cottonseeds. Interestingly, the ULGCS had significantly higher (4%–8%) oil content compared with the seeds from the nontransgenic parent. Field trial results confirmed the stability and specificity of the ULGCS trait suggesting that this RNAi‐based product has the potential to be commercially viable. Thus, it may be possible to enhance and expand the nutritional utility of the annual cottonseed output to fulfil the ever‐increasing needs of humanity.     

Metal-ion-directed site-specificity of hydroxyl radical detection.

A wide variety of .OH detectors are in use for determination of biological .OH production. The chemical generation of .OH is site-specific with respect to the metal-binding site, and thus .OH detectors with metal-binding properties may affect the biological damage and bias .OH detection. The present study shows that both salicylate and phenylalanine, added as low molecular weight .OH indicators, decreased Cu(II) binding to erythrocyte ghosts. In a cell-free system, Cu(II) complexed to both salicylate and phenylalanine. Phenylalanine is a stronger Cu(II) chelator than salicylate, both when competing for Cu(II) bound to ghosts and when competing directly with each other. When OH radicals were generated by ascorbate and Cu(II), the amount of .OH detected as dihydroxybenzoates was proportional to the amount of .OH produced. However, when phenylalanine was added to this system, the efficiency of .OH detection by salicylate strongly decreased, concomitant with the transfer of Cu(II) binding from salicylate to the amino acid. This decrease was larger than that predicted by calculations for random competition of the two detectors for .OH. Deoxyribose and mannitol, which do not bind copper appreciably, competed poorly with salicylate for the .OH. Hydroxylation of phenylalanine, on the other hand, was only slightly affected by the presence of salicylate and unaffected by deoxyribose and mannitol. These results suggest that the detection of .OH by low molecular weight .OH indicators was related to the relative affinity of the detectors for the catalyzing metal, and thus partially site-specific. Furthermore, glutamate, which does not contain an aromatic ring but binds Cu(II) with considerable affinity, competed strongly with salicylate for the .OH, indicating that metal-binding properties rather than the presence of an aromatic ring were the cause of the deviation from random competition. The results indicate that .OH indicators with metal-binding properties affect the distribution of catalytic metal ions in a biological system, causing a shift of free radical damage and localizing a site-specific reaction of .OH on these detectors, with a resulting positive bias in the apparent .OH production.     

Determining Some Osmotic Characteristics of White Pine Leaf Cells

When leaf cells of white pine, Pinus strobus L., were plasmolyzed in appropriate concentrations of glucose (0.85-0.95 M) they could be fixed in a mixture of formalin, acetic acid and alcohol, embedded in polyethylene glycol, and measurements of the degree of plasmolysis made without development of artifacts. Fresh material was prepared by freehand sectioning only with difficulty and did not always give reliable results, whereas embedding and microtome sectioning provided satisfactory material for determining the osmotic characteristics of pine foliage tissue.     

White pine weevil performances in relation to budburst phenology and traumatic resin duct formation in Norway spruce

1 As the phenological window hypothesis was reported to be significant in influencing the fitness of many herbivores feeding on tree foliage, could it also explain the performance of an insect such as the white pine weevil Pissodes strobi mainly attacking the bark phloem of conifers? 2 Under field conditions, adult weevils were caged on Norway spruce trees presenting a natural variation in their shoot growth phenology. 3 We evaluated white pine weevil biological performances, including oviposition, the number of emerged insects, survival, adult mean weight and tree defense responses as reflected by the production of induced resin canals. 4 None of the white pine weevil biological parameters was significantly affected by Norway spruce phenology. 5 The number of eggs per hole, the number of oviposition holes per leader, the number of emerged adults and their mean weight were not affected by host phenology. 6 The intensity of the traumatic response observed was variable and not correlated with budburst phenology. 7 Trees with higher traumatic responses, forming two or more layers of traumatic ducts, had lower adult emergence and estimated survival. 8 The distance between the first layer of traumatic resin ducts and the start of the annual ring was not correlated with the number of emerged weevils. 9 Norway spruce, which is an exotic tree in North America and a relatively recent host for the white pine weevil, might not possess the defense mechanisms necessary to fight off the white pine weevil.     

Exogenous salicylate application affects the lead and copper accumulation characteristics of Lemna gibba L

Previous studies have shown that salicylates can change the ion permeability of root cells. Therefore the possible effects of exogenous salicylate application on lead (Pb) and copper (Cu) accumulation and its protective role against DNA damage due to metal exposure in Lemna gibba were studied. L. gibba was exposed to 5, 10, and 25 microM Pb and Cu for six days in the presence and absence of sodium salicylate (SA) (0.1, 0.5, and 1 mM). At all concentrations tested, SA application decreased Pb accumulation. On the other hand, application of 0.5 mM SA increased Cu accumulation. SA did not reduce DNA damage resulting from Pb and Cu toxicity. In summary, SA may be useful for reducing Pb accumulation, and application of SA at 0.5 mM may be useful for the phytoextraction of Cu.     

Seasonal Variation of Western White Pine (Pinus monticola D. Don) Foliage Proteins

Recently, a western white pine protein, Pin m III, was shownto be associated with overwintering and frost hardiness of westernwhite pine foliage. To examine whether Pin m III is directlyinvolved in frost hardiness by functioning as an antifreezeprotein, work is underway to clone the gene encoding this proteinand to assess the function of this gene in freezing toleranceby incorporating the gene in a test plant, such as tobacco.Here, we examined in more detail, by SDS-PAGE and also by twodimensional gel electrophoresis, the seasonal variation of additionalproteins in western pine foliage. SDS-PAGE analysis of threeseedlots showed that different proteins reached a maximum levelin different months, although most proteins (5 to 11) reacheda maximum level in winter months (December, January and February).The 2-D gel analysis of foliage sampled on three harvest dates(October, January and April) of one seedlot revealed a seasonalvariation of a large number proteins (76 to 184). Of the seasonallyvaried proteins, the amino terminal sequence of several proteinsincluding Pin m III was determined. One of the sequences wasidentified by homology to that of the small subunit of ribulosebiphosphate carboxylase, whose level increased substantiallyfrom fall to spring. The amino terminal sequence of Pin m IIIhad 89% homology to a sugar pine protein, Pin 11. The anti-photosystemII antibody was used to monitor the annual variation of theextrinsic 23-kDa photosystem II protein. The level of the extrinsic23-kDa photosystem II protein decreased slowly as fall progressedand reached its lowest level in December and then increasedin early spring indicating that this variation is due to photosyntheticactivity of the foliage during the season. (Received July 29, 1995; Accepted March 5, 1996)     

Effects of Different Sources and Levels of Copper on Growth Performance,Nutrient Digestibility,and Elemental Balance in Young Female Mink (Mustela vison)

An experiment was conducted in a 3?×?3?+?1 factorial experiment based on a completely randomized design to evaluate the effects of different sources of copper on growth performance, nutrient digestibility and elemental balance in young female mink on a corn–fishmeal-based diet. Animals in the control group were fed a basal diet (containing 8.05 mg Cu/kg DM; control), which mainly consisted of corn, fish meal, meat bone meal, and soybean oil, with no copper supplementation. Minks in other nine treatments were fed basal diets supplemented with Cu from reagent-grade copper sulfate, tribasic copper chloride (TBCC) and copper methionate. Cu concentrations of experiment diets were 10, 25, and 40 mg/kg copper. A metabolism trial of 4 days was conducted during the last week of experimental feeding. Final body weight and average daily gain increased (linear and quadratic, P?<?0.05) as Cu increased in the diet; maximal growth was seen in the Cu25 group. Cu supplementation slightly improved the feed conversion rate (P?=?0.095). Apparent fat digestibility was increased by copper level (P?=?0.020). Retention nitrogen was increased by copper level (linear, P?=?0.003). Copper source had a significant effect on copper retention with Cu-Met and copper sulfate treatments retention more than TBCC treatments (P?<?0.05). Our results indicate that mink can efficiently utilize added dietary fat and that Cu plays an important role in the digestion of dietary fat in mink, and mink can efficiently utilize Cu-Met and CuSO₄.     

Effects of Chronic Human Activities on Invasion of Longleaf Pine Forests by Sand Pine

Chronic human activities may result in new and permanent successional trajectories in certain ecosystems. The invasion of longleaf pine ecosystems by sand pine in the Florida Panhandle is one such change in the landscape. This study examined the spatial pattern of sand pine expansion and explored the natural and anthropogenic disturbances that fostered this invasion. Aerial photographs (1949, 1994) and Geographic Information Systems analyses confirmed sand pine expansion at Eglin Air Force Base. In 1949, there were 8,982 ha of sand pine in the southern portion of the study area near riparian and coastal lowland forests. By 1994, sand pine had expanded further upland and inland, for a total of 17,147 ha in the study area. Sand pine age data showed that this expansion had started by 1920 but increased rapidly in the 1940s. Historical accounts and structural data from stands suggest that land-use activities associated with the extraction of turpentine promoted the invasion by sand pine. Fires were suppressed in longleaf pine forests to protect turpentine trees, resulting in increased vegetation cover and decreased regeneration of longleaf pine. In addition, stands were typically harvested after turpentining, and there was little or no advanced regeneration of longleaf pine. Sand pine age histograms showed that the onset of high establishment rates (1940s) coincided with changes in land ownership and widespread fire suppression. Sand pine is likely to persist in these ecosystems due to its abundant regeneration. Received 17 March 1999; accepted 28 January 2000.     

Is the Lower Shade Tolerance of Scots Pine,Relative to Pedunculate Oak,Related to the Composition of Photosynthetic Pigments?

Foliage of Scots pine (Pinus sylvestris L.) and pedunculate oak (Quercus robur L.) was collected in a mixed pine/oak forest at canopy positions differing in radiation environment. In both species, chlorophyll (Chl) a/b ratios were higher in foliage of canopy positions exposed to higher irradiance as compared to more shaded crown layers. Throughout the growing season, pine needles exhibited significantly lower Chl a/b ratios than oak leaves acclimated to a similar photon availability. Hence, pine needles showed shade-type pigment characteristics relative to foliage of oak. At a given radiation environment, pine needles tended to contain more neoxanthin and lutein per unit of Chl than oak leaves. The differences in pigment composition between foliage of pine and oak can be explained by a higher ratio of outer antennae Chl to core complex Chl in needles of P. sylvestris which enhances the efficiency of photon capture under limiting irradiance. The shade-type pigment composition of pine relative to oak foliage could have been due to a reduced mesophyll internal photon exposure of chloroplasts in needles of Scots pine, resulting from their xeromorphic anatomy. Hence, the higher drought tolerance of pine needles could be achieved at the expense of shade tolerance.