Spectral composition of shade light in coastal-zone oak forests in SE Bulgaria,and relationships with leaf area index: a first overview

Major knowledge gaps exist with respect to light-quality regimes in the coastal-zone Strandzha Quercus frainetto (Q.f.) forest region adjoining the southern Bulgarian Black Sea. This paper presents preliminary results that help narrow these gaps. In conjunction with leaf area index (LAI) field campaigns we undertook measurements with an array of 7 broad-band (ca 40 nm) sensors covering the range 0.40–0.94 μm, plus 1 sensor for UVB (0.297 μm peak) and 1 for photosynthetically active radiation (PAR). Measurements focused on inside-forest shade conditions at sites 0 to ca 15 km from the Black Sea and at altitudes up to ca 120 m above sea level. Some of the sites were also studied using a high-resolution spectroradiometer. A sequential measuring strategy was necessary. This involves potentially large uncertainties, here addressed through estimations of the variability around the sinusoidal course of daylight. Light-quality regimes were found to be in general support of earlier studies of deciduous forests. Our data from the broad-band sensors and from the spectroradiometer are mutually supportive. They indicate a stronger red-shift below Q.f. canopies than below canopies in enclaves dominated by Fagus orientalis and Pinus sylvestris. Transmission in the range 0.50–0.55 μm increases beneath the three types of canopies, most pronounced in the Q.f. case. Analysis of relationships between the inside-forest to open-field irradiance ratio and LAI supports the use of Beer’s Law. We found a fairly strong relationship between the red (0.66 μm) to far-red (0.73 μm) irradiance ratios (R/FR) and LAI for the Q.f. forest. In quantitative terms, the result is new for this Q.f. region, and suggests further research to explore whether a two-sensor approach (0.66 and 0.73 μm) might offer possibilities for further low-cost mapping of the spatio-temporal patterns of R/FR and LAI in Strandzha. Such mapping would assist in further studies of the region’s forest biogeochemistry and vitality.     

In vitro response of leaf tissues from Lolium multiflorum — a comparison with leaf segment position,leaf age and in vivo mitotic activity

Summary Immature gramineous leaves provide a convenient system for comparing the response of cells in culture with their state of differentiation. Callusing frequency is compared with leaf segment position, leaf age and in vivo mitotic activity in Lolium multiflorum. (1) In a succession of one millimeter sections from the immature leaf base, callus was formed from the first and second sections but not the third or subsequent sections. The frequency of those explants callusing decreased with distance from the base of the leaf and with leaf age (or leaf extension growth). (2) In vivo, the proportion of cells in mitosis declined from around 10–14% at the base of young leaves to zero at 5 mm from the base and beyond. Mitotic activity also declined in leaves as they aged, and dividing cells were not observed in leaves 30 days from initiation or older. (3) A high frequency of callus formation was associated with a high mitotic index in the explant. But for corresponding mitotic indices, cells further away from the leaf base were less responsive in culture. (4) It is proposed that cells are becoming differentiated even in highly meristematically active regions of the leaf and concomitantly losing their ability to respond in culture.     

Flora Palinologica Italiana,Sezione Aeropalinologica — Specie esotiche — S 231:Sequoia sempervirens (Lamb.) Endl. (Taxodiaceae)

Riassunto La scheda morfopalinologica diSequoia sempervirens (Lamb.) Endl. continua lo studio sulle Pinohyta ornamentali più frequenti in Torino. È esaminato polline fresco ed acetolizzato proveniente da due stazioni e la provenienza non determina variazioni significative dei parametri morfometrici.

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Summary The morphopalynological card ofSequoia sempervirens (Lamb.) Endl. is a new contribution to the comprehensive study on pollen of ornamental Pinophyta in Turin. Fresh and acetolysed grains from two stations are examined, and for all parameters no significative differences were observed in relation to the collection site.

Parole chiave: Sequoia sempervirens(Lamb.) Endl., Flora Palinologica Italina, Sezione Aeropalinologica.     

Feeding graded levels of dried Sea buckthorn (Hippophaes rhamnoides) berries to broiler chickens

The aim of this study was to assess the effects of graded levels (0, 3, 6, 9 and 12 g/kg) of dry Sea buckthorn (SB) berries on growth performance, gastrointestinal tract (GIT) development, jejunal histomorphology, bird antioxidant status and caecal short-chain fatty acid concentration when fed to female Ross 308 broiler chickens. In addition, expression of cytokine biomarker genes in the jejunum was evaluated. The five experimental diets were fed from 7 to 21 days age to 8 pens (two birds in each) following randomisation. Feeding SB did not influence bird growth performance (p > .05). There was a linear decrease in butyric, acetic and valeric acid concentrations in caecal digesta (p < .05) and a decrease (p < .05) in crypt depth. The expression of IFNG and CD40LG responded quadratically (p < .05), peaking at 6–9 g/kg dietary inclusion of SB, respectively. Other studied variables were not affected by dietary SB inclusion (p > .05). Feeding dry SB berries up to 12 g/kg of diet did not improve the zootechnical variables of healthy commercial-strain broilers in this study.     

Improvement of persistence and yield of Italian ryegrass (Lolium multiflorum) through pesticide use

The present two field experiments, involving plots of Italian ryegrass sown in 1976, 1980 and 1984 confirmed results of earlier work in which the yield and persistence of Italian ryegrass was greatly increased by the application of pesticide. A range of pesticide treatments were used. The responses to application of permethrin applied three times per year average 8% for the three years of the first experiment and 5% for the five years of the second experiment. Such responses appeared cost-effective, but the overall environmental impact of such applications is not known.     

Characterization of 59 canine single nucleotide polymorphisms in the Italian wolf (Canis lupus) population

We characterized 59 canine single nucleotide polymorphisms (SNPs) in the endangered Italian wolf (Canis lupus) population, which were discovered by resequencing sequence‐tagged‐site (STS) DNA sequences that are known to contain SNPs in domestic dogs. Dog SNPs were usually found also in wolves. Additional SNPs unique in dogs or wolves were discovered, which is important for detecting hybrids between dogs and wolves. We developed new primer sets and analysed 15 SNPs by Pyrosequencing. The characterized SNPs will provide an important addition to the genetic markers that are currently available for studying wild populations of canids.     

Acidophytic shrublands in the north-west of the Italian peninsula: Ecology,chorology and syntaxonomy

Abstract

The shrublands growing on siliceous and/or calcium-poor substrata of the hilly and mountainous areas of north-western and central Italy were studied. This secondary vegetation is dominated by several acidophilous shrubs like Ulex europaeus, Cytisus scoparius, Erica arborea, E. scoparia and Calluna vulgaris. The synecology, synchorology and syntaxonomy of this vegetation was studied using multivariate methods, and discussed in comparison with similar types described in other zones of the Italian peninsula. Two new subassociations are proposed here: Erico arboreae-Arbutetum unedonis genistetosum germanicae and Calluno-Sarothamnetum ericetosum scopariae. Calluno-Sarothamnetum is typified; the Sarothamnion alliance is discussed and referred to Cytisetea scopario-striati. The presence of Calluno-Ulicetea and Cytisetea scopario-striati classes is discussed, and a syntaxonomical scheme is proposed.     

Conspectus of Italian Selaginella (Selaginellaceae), with some typifications

An annotated synonymic inventory of Italian Selaginella taxa, a practical key for their identification and their dot distribution maps are presented, as a result of our work on the Selaginellaceae account for the Flora Critica d'Italia. The names Lycopodium helveticum L. and Selaginella denticulata var. platystachya Hieron. are typified.     

Effects of chemical pollutants on reproductive and developmental processes in Italian amphibians

It is a widely held belief that environmental contaminants contribute to the decline of amphibian populations. By spending most of their early life in water and later stages on the land, amphibians face a constant risk of exposure to pesticides and other chemical pollutants in both aquatic and terrestrial environments. This review presents an overview of the studies carried out in Italian amphibians to highlight hazardous effects of bioaccumulation of chemical pollutants in juveniles and adults in various contaminated environments. Further, the studies in the laboratory setting assessing the effects of chemical pollutants on reproductive and developmental processes are reported. These studies and their relative references have been summarized in a tabular form. Three prominent contaminant groups were identified: herbicides, insecticides, and fungicides; and only a few works reported the effects of other chemical pollutants. Each pollutant group has been delegated to a section. All through the literature survey, it is seen that interest in this topic in Italy is very recent and sparse, where only a few anuran and caudata species and only some chemical pollutants have been studied.     

Genetic differentiation and history of populations of the Italian treefrog Hyla intermedia: lack of concordance between mitochondrial and nuclear markers

The genetic differentiation among 33 populations of the Italian treefrog, Hyla intermedia (Anura: Hylidae), was investigated using both biparentally (23 allozyme loci) and maternally (partial mitochondrial cytochrome b gene) inherited markers. Two main population groups were evidenced by both markers, located north and south of the northern Apennines. However, the pattern of differentiation between these two groups was much less pronounced at allozymes than at mtDNA, leading to gene flow estimates that were 25 times lower at mitochondrial than at nuclear level. Also, the mtDNA divergence between the two groups was particularly marked for two cospecific lineages of anuran amphibians (the P-distance being on average 9.04%), while their average genetic distance at allozymes was comparatively low (D _NEI = 0.07). This contrasting pattern of nuclear versus mitochondrial genetic variation is discussed in the context of: (1) marker specific selection, (2) secondary contact and sex-biased gene flow and (3) ancestral polymorphism and colonization from north to south. Finally we emphasize how, for population genetic studies, the use of multiple markers having distinct evolutionary properties can help unravel the existence of more complex evolutionary histories.