Search

In modern agricultural production, cattle manure waste recovery is considered as a sustainable approach to agricultural waste management, reducing environmental pollution and chemical fertilizer use. This study aimed to investigate the effects of manure and digestate derived from a pilot-scale livestock waste-recycling system, in combination with a low copper concentration as a fungicide, on the physiological response of lettuce cv Rufus (Lactuca sativa L.) plants and the associated soil microbiome. A five-week microcosm experiment was conducted in a greenhouse under environmental conditions. Lettuce plant performance was assessed in terms of biomass, leaf area index, photosynthetic activity, chlorophyll measurements, lipid peroxidation, total phenolic content, and nutrient uptake. The results suggested that incorporating digestate into the potting soil mix significantly enhanced crop yields compared to the control and manure treatments. The soil microbial activity increased in the presence of fertilizers, improving the soil chemical and biological properties. The addition of copper negatively affected the growth and physiological performance of the lettuce plants under both the control and manure-treated conditions, except for those grown in the presence of digestate, where copper accumulation was reduced. These findings highlight the potential of growing horticultural crops using organic fertilization through livestock waste anaerobic digestate, establishing a waste-to-food recycling system. [ABSTRACT FROM AUTHOR]

Lemnaceae taxonomy is challenged by the particular morphology of these tiny free-floating angiosperms. Although molecular taxonomy has helped clarify the phylogenetic history of this family, some inconsistency with morphological data leads to frequent misclassifications in the genus Lemna. Recently, the finding that Lemna japonica is an interspecific hybrid between Lemna minor and Lemna turionifera provided a clear explanation for one such taxonomic question. Here we demonstrated that L. minor is also capable of hybridizing with Lemna gibba , generating a cryptic but widespread taxon in the Mediterranean area. The nothotaxon Lemna × mediterranea is described and compared with clones of the putative parental species L. minor and L. gibba. Genetic analysis by nuclear and plastid markers, as well as genome size measurement, revealed that two different cytotypes, diploid and triploid, originated by at least two independent hybridization events. Despite high overall similarity, morphometrical, physiological, and biochemical analyses showed an intermediate position of L. × mediterranea between its parental species in most qualitative and quantitative characters, and also separation of the two hybrid cytotypes by some criteria. These data provide evidence that hybridization and polyploidization, driving forces of terrestrial plant evolution, contribute to duckweed genetic diversity and may have shaped the phylogenetic history of these mainly asexual, aquatic plants. [ABSTRACT FROM AUTHOR]

The demographic and reproductive structure of populations represents the main data set needed for conservation and management plans. Mediterranean red coral Corallium rubrum has been exploited for 2,000 years, but only recently management plans have been solicited by the international community. We examined and compared the demographic features of two red coral shallow populations located in distinct geographic locations: Portofino (Italy) and Cap de Creus (Spain). adults and juveniles density, growth rates, population size and age structure, fecundity and fertility were examined. Juveniles were the dominant class (33 %) in both populations. The analysis of the gamete content of 653 colonies revealed that the populations have balanced sex ratios and similar fertility and polyp fecundity. The average annual growth rate, determined on 119 colonies by annual growth rings count, was similar in both populations (0.24 mm [year.sup.-1]), decreasing with colony age. Maximum life span of 99 % of the colonies was 60 and 40 years at Portofino and Cap de Creus, respectively. Minimum harvestable size (7 mm basal diameter) was reached in 30-35 years, and the percentage of colonies above it was 6.7 % at Portofino and 2.1 % at Cap de Creus, where juvenile and adult colony densities were significantly lower and the percentage of commercial-sized colonies reduced by 25 % in just a few years. Notwithstanding similar growth and fecundity, the two populations showed different densities and size/age structures suggesting local factors, together with different fishing pressures, have to be taken into account in the management plans for this species., Introduction Population dynamics depend largely on demographic histories (Dobson 1998; Ebert 1999, particularly for slow-growing, long-lived species, which have been subjected to dramatic reductions in survival, reproduction and/ or recruitment [...]

Metal pollution in waters and soils is a major environmental and human health problem. Cadmium (Cd2+) is a heavy metal displaying toxic effects in plants. In this work we studied the potentiality of Lemna minor, a monocotyledonous aquatic macrophyte, to phytoremediate cadmium-polluted waters. The plants were exposed to different cadmium concentrations 0, 13, 22 and 46μM CdSO4 for a period of 24, 48 and 72 hours. Relative growth rates (RGR), bioconcentration factor (BCF), tolerance index (Ti), cadmium uptake in whole plant and maximum efficiency of PSII (Fv/Fm) were measured under controlled climate conditions. RGR, Ti and Fv/Fm declined with increasing exposure time and cadmium concentrations, while the BCF and cadmium uptake showed an opposite behavior. Data analysis of RGR, BCF, Tiand FV/FM indicates that L. minor maintains a good capacity of growth, metal bioconcentration, tolerance and efficiency of PSII up to 48h in plants exposed to 13 and 22μM CdSO4. Our results exhibited that L. minor is a good cadmium accumulator and is able to remediate Cd-polluted waters, especially at low Cd concentrations.

Mental retardation and personality disorders are commonly described among the symptoms of myotonic dystrophy. Nevertheless, this tendency is not supported by systematic studies performed on large samples, whose results are controversial. We studied the cognitive functions and personalities of a group of 28 patients, in whom myotonic dystrophy had commenced in juvenile or adult life. The severity of the disease was variable, but all subjects were self-sufficient. Only 7.1% of subjects showed low intelligence with deterioration of perceptual-motor functions. This was not correlated with the severity of their disease. Women had a substantially lower mean Wechsler-Bellevue score than men. The personality function study of the entire group showed no change of psychiatric relevance but did present a depressive attitude with marked somatic concern and difficulties in establishing relationships in social life.

Over the last years, several marine populations suffered a drastic mortality increase of different origins; assessing the changes occurring in the demographic structure of such populations will allow evaluating their future trends and their ultimate fate. The aim of our research was to assess main demographic descriptors and related dynamics in populations of the Mediterranean gorgonians Paramuricea clavata and Corallium rubrum (the 'precious red coral') both subject to increased mortality, by life-history tables and Leslie-Lewis transition matrices. Gorgonian populations have been generally been considered to have low recruitment and low dynamics. Here, we test whether these features change when mortality rises and if such populations can reach new equilibria? Our findings show large differences between the two species examined, with lower recruitment and adult colony density, shorter life-span but over-abundant reproductive output in P. clavata. Recruitment density dependence was found in crowded populations of both species, albeit with different trends. Populations of both species tend to recover even after drastic mortality increase and P. clavata reaches a new equilibrium at lower densities than at pristine values, and this in a few years time. The findings in this review could shed some light on the poorly understood dynamics occurring in deep-water dwelling, affected populations of long-lived and slow-growing gorgonian corals. [ABSTRACT FROM AUTHOR]

We present a model for describing the spread of an infectious disease with public screening measures to control the spread. We want to address the problem of determining an optimal screening strategy for a disease characterized by appreciable duration of the infectiveness period and by variability of the transmission risk. The specific disease we have in mind is the HIV infection. However the model will apply to a disease for which class-age structure is significant and should not be disregarded. [ABSTRACT FROM PUBLISHER]

The optimal conditions to prepare α,β-unsaturated methyl esters via Wittig reaction combining polymer-assisted solution-phase synthesis (PASPS) methodology and simultaneous ultrasound and microwave irradiation were established. The effects of temperature, solvent, and irradiation time were discussed. Results clearly indicated the superiority of combined ultrasound and microwave-assisted procedure over microwave-assisted methodology. Moreover, an efficient PASPS procedure to prepare α,β-unsaturated carboxylic acids via tandem Wittig olefination and hydrolysis reaction was developed under combined ultrasound and microwave irradiation. Generally, a good conversion of aldehydes to acids was observed. The optimized protocols allowed us to quickly prepare a small collection of either α,β-unsaturated esters or carboxylic acids, key intermediates for the drug-discovery process of new sigma ligands. [ABSTRACT FROM AUTHOR]

Transgene escape risks are evaluated by assessing the frequency of transgenic hybrids within populations sexually compatible with those genetically modified. We examined the pollen-mediated transgene flow among lettuce varieties in Italy. Transgenic ‘Luxor’ lines harboured the arabidopsis KNAT1 gene, which caused leaf trait alterations, and the bacterial NPTII gene for resistance to kanamycin. Donor homozygous lines ( KNAT1:NPTII/ KNAT1:NPTII) were used in two trials: in glasshouse, ‘Luxor’ transgenic and conventional plants were spaced at 15 cm; in field, a transgenic ‘Luxor’ donor island was set up and surrounded by 10 pollen receiver varieties sited at 0.5, 11 and 22 m. Progenies of recipient cultivars were screened by kanamycin assays, leaf alterations, transgene transcription and integrity. The out-crossing rate (OCR) was calculated as the frequency of KNAT1:NPTII/− and δ KNAT1:NPTII/− genotypes because KNAT1 impair (indicated with δ) was observed to vary from the 0.03% to 0.36%. Indoor, ‘Luxor’ intra-varietal OCR was 0.41 ± 0.11%; outdoor, the average inter-varietal OCR was 0.49%, 0.071% and 0.035% for plants at 0.5, 11 and 22 m, respectively. [ABSTRACT FROM AUTHOR]

Abstract At suboptimal temperatures, anthocyanins accumulate in the illuminated leaf surface of some maize genotypes and, if the anthocyanins shade chloroplasts, they can effectively reduce the risk of photo-inhibition but also photo-synthesis. To investigate this phenomenon, gas exchange, fluorescence, superoxide dismutase activity and xantho-phyll composition of anthocyanin-containing HOPI and anthocyanin-deficient W22 maize genotypes were measured in either white or red light, where the latter is not absorbed by anthocyanins. Despite differences in light absorption in chloroplasts, photosynthesis did not differ between HOPI and W22 under either light source, suggesting that neither CO2 supply nor photochemistry were more limiting in red leaves than in green leaves. In fact, no major differences in transpiration were detected. The ΔF /F m (photosystem II quantum yield) of HOPI in white light was higher than in red light and higher than ΔF /F m of W22 with either light source. This probably compensated for the lower white light absorption of HOPI chloroplasts compared with W22 because of the presence of anthocyanins and led to similar rates of calculated electron transport for both genotypes. After exposure to high white light at 5 °C, xanthophyll de-epoxidation and superoxide dismutase activity were lower in HOPI than in W22. Further, HOPI could be exposed to a much higher irradiance than W22 before F v /F m was reduced to that of W22. [ABSTRACT FROM AUTHOR]