The effect of surface fire on tree ring growth of <Emphasis Type="Italic">Pinus radiata</Emphasis> trees

Key message

Pinus radiata trees showed significantly reduced basal area increments and increased latewood/earlywood ratios, when their stem was charred by surface fires even if no needle damage occurred. An interaction of fire damage and precipitation on growth was observed.

Context

Heat from forest fires is able to penetrate beyond the bark layer and damage or completely kill a tree’s cambium. Short-term growth reductions following surface fires have been reported for some species. However, most studies have in common that they describe a compound effect of stem and foliage damage.

Aims

This study investigated the impact of surface fires on the radial growth of Pinus radiata, where only the stem of trees was charred, while no needle damage was recorded.

Methods

Tree ring measurements were performed on cores obtained at breast height. Analysis of variance and tests, based on annual basal area increment values were calculated to quantify pre- and post-fire growth differences of tree ring width and latewood/earlywood ratios.

Results

The analysis revealed significant growth reductions following a surface fire on P. radiata in the year on which the fire occurred as well as in the following year. As a consequence of the fire, basal area increment and latewood/earlywood ratios were significantly reduced. An interaction of fire damage and precipitation on growth was observed.

Conclusion

The obtained results show how fires without crown damage can affect growth and tree ring structure of P. radiata trees and indicate that stem char could be associated with a significant decrease in ring width and latewood/earlywood ratio.

     

Defining competition vectors in a temperate alley cropping system in the midwestern USA: 1. Production physiology

With renewed interest in the use of ecologically-designed, sustainable agricultural systems for temperate regions of the world, agroforestry is being proposed as an alternative to intensive production of crops in monocultures. However, the knowledge-base for understanding and managing complex, multi-strata systems worldwide is limited, particularly so for temperate regions. We examined an alley cropping system in the midwestern US where maize (Zea mays L.) is grown in alleys between tree rows of either black walnut (Juglans nigra L.) or red oak (Quercus rubra L.). During a course of ten years, crop yields in rows adjacent to tree rows declined by 50% or more. With the experimental introduction of barriers to separate tree and crop root systems, yields in the rows near trees were equal to those of the center row (and monoculture). Irrespective of a high correlation between photosynthetically active radiation and net photosynthesis, shading did not have a major influence on crop yield. At this stage of system development (11 year old trees), influence of incident PAR on crop yield seems to be minimal. Subsequent papers in this series examine the sharing of belowground resources between trees and crops to quantify the competitive interactions that impact crop yields and their implications for economic return to the farmer.This revised version was published online in November 2005 with corrections to the Cover Date.     

Phylogeny and nomenclature of the genus Talaromyces and taxa accommodated in Penicillium subgenus Biverticillium

The taxonomic history of anamorphic species attributed to Penicillium subgenus Biverticillium is reviewed, along with evidence supporting their relationship with teleomorphic species classified in Talaromyces. To supplement previous conclusions based on ITS, SSU and/or LSU sequencing that Talaromyces and subgenus Biverticillium comprise a monophyletic group that is distinct from Penicillium at the generic level, the phylogenetic relationships of these two groups with other genera of Trichocomaceae was further studied by sequencing a part of the RPB1 (RNA polymerase II largest subunit) gene. Talaromyces species and most species of Penicillium subgenus Biverticilliumsensu Pitt reside in a monophyletic clade distant from species of other subgenera of Penicillium. For detailed phylogenetic analysis of species relationships, the ITS region (incl. 5.8S nrDNA) was sequenced for the available type strains and/or representative isolates of Talaromyces and related biverticillate anamorphic species. Extrolite profiles were compiled for all type strains and many supplementary cultures. All evidence supports our conclusions that Penicillium subgenus Biverticillium is distinct from other subgenera in Penicillium and should be taxonomically unified with the Talaromyces species that reside in the same clade. Following the concepts of nomenclatural priority and single name nomenclature, we transfer all accepted species of Penicillium subgenus Biverticillium to Talaromyces. A holomorphic generic diagnosis for the expanded concept of Talaromyces, including teleomorph and anamorph characters, is provided. A list of accepted Talaromyces names and newly combined Penicillium names is given. Species of biotechnological and medical importance, such as P. funiculosum and P. marneffei, are now combined in Talaromyces. Excluded species and taxa that need further taxonomic study are discussed. An appendix lists other generic names, usually considered synonyms of Penicillium sensu lato that were considered prior to our adoption of the name Talaromyces. TAXONOMIC NOVELTIES: Taxonomic novelties:New species - Talaromyces apiculatus Samson, Yilmaz & Frisvad, sp. nov. New combinationsand names - Talaromyces aculeatus (Raper & Fennell) Samson, Yilmaz, Frisvad & Seifert, T. albobiverticillius (H.-M. Hsieh, Y.-M. Ju & S.-Y. Hsieh) Samson, Yilmaz, Frisvad & Seifert, T. allahabadensis (B.S. Mehrotra & D. Kumar) Samson, Yilmaz & Frisvad, T. aurantiacus (J.H. Mill., Giddens & A.A. Foster) Samson, Yilmaz, & Frisvad, T. boninensis (Yaguchi & Udagawa) Samson, Yilmaz, & Frisvad, T. brunneus (Udagawa) Samson, Yilmaz & Frisvad, T. calidicanius (J.L. Chen) Samson, Yilmaz & Frisvad, T. cecidicola (Seifert, Hoekstra & Frisvad) Samson, Yilmaz, Frisvad & Seifert, T. coalescens (Quintan.) Samson, Yilmaz & Frisvad, T. dendriticus (Pitt) Samson, Yilmaz, Frisvad & Seifert, T. diversus (Raper & Fennell) Samson, Yilmaz & Frisvad, T. duclauxii (Delacr.) Samson, Yilmaz, Frisvad & Seifert, T. echinosporus (Nehira) Samson, Yilmaz & Frisvad, comb. nov. T. erythromellis (A.D. Hocking) Samson, Yilmaz, Frisvad & Seifert, T. funiculosus (Thom) Samson, Yilmaz, Frisvad & Seifert, T. islandicus (Sopp) Samson, Yilmaz, Frisvad & Seifert, T. loliensis (Pitt) Samson, Yilmaz & Frisvad, T. marneffei (Segretain, Capponi & Sureau) Samson, Yilmaz, Frisvad & Seifert, T. minioluteus (Dierckx) Samson, Yilmaz, Frisvad & Seifert, T. palmae (Samson, Stolk & Frisvad) Samson, Yilmaz, Frisvad & Seifert, T. panamensis (Samson, Stolk & Frisvad) Samson, Yilmaz, Frisvad & Seifert, T. paucisporus (Yaguchi, Someya & Udagawa) Samson & Houbraken T. phialosporus (Udagawa) Samson, Yilmaz & Frisvad, T. piceus (Raper & Fennell) Samson, Yilmaz, Frisvad & Seifert, T. pinophilus (Hedgcock) Samson, Yilmaz, Frisvad & Seifert, T. pittii (Quintan.) Samson, Yilmaz, Frisvad & Seifert, T. primulinus (Pitt) Samson, Yilmaz & Frisvad, T. proteolyticus (Kamyschko) Samson, Yilmaz & Frisvad, T. pseudostromaticus (Hodges, G.M. Warner, Rogerson) Samson, Yilmaz, Frisvad & Seifert, T. purpurogenus (Stoll) Samson, Yilmaz, Frisvad & Seifert, T. rademirici (Quintan.) Samson, Yilmaz & Frisvad, T. radicus (A.D. Hocking & Whitelaw) Samson, Yilmaz, Frisvad & Seifert, T. ramulosus (Visagie & K. Jacobs) Samson, Yilmaz, Frisvad & Seifert, T. rubicundus (J.H. Mill., Giddens & A.A. Foster) Samson, Yilmaz, Frisvad & Seifert, T. rugulosus (Thom) Samson, Yilmaz, Frisvad & Seifert, T. sabulosus (Pitt & A.D. Hocking) Samson, Yilmaz & Frisvad, T. siamensis (Manoch & C. Ramírez) Samson, Yilmaz & Frisvad, T. sublevisporus (Yaguchi & Udagawa) Samson, Yilmaz & Frisvad, T. variabilis (Sopp) Samson, Yilmaz, Frisvad & Seifert, T. varians (G. Sm.) Samson, Yilmaz & Frisvad, T. verruculosus (Peyronel) Samson, Yilmaz, Frisvad & Seifert, T. viridulus Samson, Yilmaz & Frisvad.     

Relative contribution of initial root and shoot morphology in predicting field performance of hardwood seedlings

Single and multiple linear regression techniques were used to explain the capacity of initial seedling root volume (Rv) and first-order lateral roots (FOLR) relative to shoot height, diameter, and fresh mass to serve as important indicators of stock quality and predictors of first- and second-year height and diameter on an afforestation site in southern Indiana, USA. This was accomplished for northern red oak (Quercus rubra L.), white oak (Quercus alba L.), and black cherry (Prunus serotina Ehrh) seedlings graded into four Rv categories at establishment. Field survival was high (85–97%) for all species. Initial diameter, height, fresh mass, and Rv provided similar predictive ability of second-year field response for absolute height (R² = 0.59–0.77) and diameter (R² = 0.50–0.73) for both oak species. Initial seedling Rv was a better predictor of field response than FOLR for both oak species, though not for cherry. Multiple-variable models accounted for a greater proportion of the total variation in seedling field height and diameter than did single-variable equations. The high R² (up to 0.95) of regression models suggests field performance of these species can be reliably predicted and confirms the importance of initial seedling morphology in dictating early plantation performance.     

The pathomorphology and pathogenesis of acute cardiovascular failure in swine. 2. Histopathologic findings in the myocardium of swine of different populations

Histopathological alterations of the myocardium (inflammatory processes, fibrolysis, fibronecrosis, dystrophic calcification, fatty degeneration of fibres, sarcosporidia) were recorded for quantitative evaluation from 200 hearts which had been collected from clinically intact pigs for slaughter of different populations (Leicoma, land race, Schwerfurt breed, Belgian land race). Both incidence and severity of myocardial damage in pigs of stress-sensitive populations were higher with significance than those in the less stress-sensitive Leicoma population oriented to breeding. The highest rate of pathological processes was recorded from hearts of the Schwerfurt breed. These alterations were interpreted as objectively measurable expressions of breed-dependent differences in cardiovascular stability. In this context, rates of damage were higher in hearts of low absolute mass.