Stand biometry and leaf area distribution in an old olive grove at Andria, southern Italy

The objectives of this paper were (1) to provide general biometry data for an 80-year-old olive (Olea europea L., cv. Coratina) grove in Andria, southern Italy, and (2) to compare different methods for estimating leaf area distributions. Stand biometry was represented by a stocking density of 132 trees ha^?1, mean spacing of 8.7 m and mean social area (proportional to spacing and tree size) of about 76 m² per tree. Trunk total circumference averaged 110 cm and after subtraction of missing or dead parts of stems averaged 81 cm, projected area of crowns averaged 17.7 m² and the mean tree height was 4.9 m. Leaf distribution was evaluated using calibrated ground-based side photographs through image analysis and through using a simple canopy-layer model (considering hollow volume within tree crowns) and double-Gaussian curves. The mean leaf size was about 5 cm² (distributed in a log-normal manner over the range of 2 to 12 cm²). Considering whole tree crowns, the mean leaf density was about 2.6 m²m^?3; the maximum leaf area occurred in canopy layers between 1.5 to 3 m, tailing with a steeper slope to the crown base and a less steep slope to the tree-top. The foliated volume of olive crowns (mean 33.2 m³) contained on average 145 thousand leaves of the total area of 72.6 m². The corresponding leaf area index on the stand level (LAI _grove = 0.96), was rather low due to low stocking density. However when taking into account only the projected crown areas (and avoiding free space between trees), the mean LAI reached about 3.5 (range from 1–7). The radial pattern of leaf distribution derived from image analysis indicated peak LAI _rad values at a distance from the stem of about 60 to 70% of crown radius in trees of different size. The applicability of different approaches to the estimation of the necessary allometric parameters is discussed.     

Concept and feasibility study for the integrated evaluation of environmental monitoring data in forests

In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis (crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative, as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.

Predicting moisture content and density distribution of Scots pine by microwave scanning of sawn timber II: evaluation of models generated on a pixel level

The purpose of this study was to use images from a microwave sensor on a pixel level for simultaneous prediction of moisture content and density of wood. The microwave sensor functions as a line-scan camera with a pixel size of 8mm. Boards of Scots pine (Pinus sylvestris), 25 and 50mm thick, were scanned at three different moisture contents. Dry density and moisture content for each pixel were calculated from measurements with a computed tomography scanner. It was possible to create models for prediction of density on a pixel level. Models for prediction of moisture content had to be based on average values over homogeneous regions. Accuracy will be improved if it is possible to make a classification of knots, heartwood, sapwood, etc., and calibrate different models for different types of wood. The limitations of the sensor used are high noise in amplitude measurements and the restriction to one period for phase measurements.     

Effects of elevated CO(2) concentration and nutrition on net photosynthesis,stomatal conductance and needle respiration of field-grown Norway spruce trees

To study the effects of elevated CO(2) on gas exchange, nonstructural carbohydrate and nutrient concentrations in current-year foliage of 30-year-old Norway spruce (Picea abies (L.) Karst.) trees, branches were enclosed in ventilated, transparent plastic bags and flushed with ambient air (mean 370 &mgr;mol CO(2) mol(-1); control) or ambient air + 340 &mgr;mol CO(2) mol(-1) (elevated CO(2)) during two growing seasons. One branch bag was installed on each of 24 selected trees from control and fertilized plots. To reduce the effect of variation among trees, results from each treated branch were compared with those from a control branch on the same whorl of the same tree. Elevated CO(2) increased rates of light-saturated photosynthesis on average by 55% when measured at the treatment CO(2) concentration. The increase was larger in shoots with high needle nitrogen concentrations than in shoots with low needle nitrogen concentrations. However, shoots grown in elevated CO(2) showed a decrease in photosynthetic capacity compared with shoots grown in ambient CO(2). When measured at the internal CO(2) concentration of 200 &mgr;mol CO(2) mol(-1), photosynthetic rates of branches in the elevated CO(2) treatments were reduced by 8 to 32%. The elevated CO(2) treatment caused a 9 to 20% reduction in carboxylation efficiency and an 18% increase in respiration rates. In response to elevated CO(2), starch, fructose and glucose concentrations in the needles increased on average 33%, whereas concentrations of potassium, nitrogen, phosphorus, magnesium and boron decreased. Needle nitrogen concentrations explained 50-60% of the variation in photosynthesis and CO(2) acclimation was greater at low nitrogen concentrations than at high nitrogen concentrations. We conclude that the enhanced photosynthetic rates found in shoots exposed to elevated CO(2) increased carbohydrate concentrations, which may have a negative feedback on the photosynthetic apparatus and stimulate cyanide-resistant respiration. We also infer that the decrease in nutrient concentrations of needles exposed to elevated CO(2) was the result of retranslocation of nutrients to other parts of the branch or tree.     

Farmers' production of timber trees in the cacao-coffee region of coastal Ecuador

The coastal region of Ecuador is an important producer of cacao and coffee. Increasingly, farms and ranches in the region also provide industrial wood for sawmills and other wood processing plants. Most of this wood derives from shade trees and pasture trees. Because little is known of wood supply from farm sources in coastal Ecuador, a survey was conducted of 122 farmers in the subregions of Ventanas, La Troncal, and Babahoyo. The survey indicates an abundance of land for the growing of farm trees, and excellent regeneration of many species on the majority of farms. However, current stocking of farm trees seems well below potential, and fewer than half of interviewed owners deliberately manage farm trees for eventual sale as timber. Only 2.2 percent of gross farm revenue derives from tree sales, even though over half of surveyed farmers have sold trees to industrial buyers at least once. Constraints on production and sales of farm trees for timber include risks of damage to coffee and cacao; perceived incompatibilities with current farming practices; inadequate methods of classification and pricing of farm trees; and insufficient knowledge of the industrial uses of farm trees by agricultural extensionists. These limitations need to be addressed through a strategy of research, development, and information diffusion on selected demonstration farms.

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Resúmen La región costera del Ecuador es una productora importante de cacao y café. Cada vez más, las fincas de la región proveen madera industrial para asseraderos y otros procesores madereros. La mayoría des esta madera viene de árboles de sombra. Dado que se sabe poco de la cantidad de madera provieniente de fincas en la costa del Ecuador se hizo una encuesta a 122 agricultores en las subregiones de Ventanas, La Troncal, y Babahoyo. La encuesta indica que existe una abundancia de terreno disponible para la producción de árboles de sombra y una regeneración excelente de muchas especies en la mayoría de las fincas. Sin embargo, densidades de los árboles de sombra parece bastante debajo de su nivel potencial, y menos de la mitad de los agricultores entrevistados cultivan sus árboles con el fin de venderlos eventualmente. De los entrevistados, un promedio de 2,2 porciento de ingresos brutos anuales provienen de ventas de árboles, a pesar de que más de la mitad de los agricultores han vendido árboles a compradores industriales por lo menos una vez. Limitaciones a la producción y a la venta de estos árboles incluyen el riesgo de daños a las plantas de cacao y cafe; la percibida incompatibilidad con las prácticas agrícolas usuales, métodes inadecuados de clasificar y poner precio a los árboles, y el poco conocimiento de los usos industriales de árboles de sombra por parte de los extensionistas agrícolas. Se necesita enfocar atención a estas limitaciones a través de una estrategia de investigación, desarrollo, y difusión de información en seleccionadas fincas demonstrativas.

     

Factors affecting costs for on-farm control of salmonella in Swedish dairy herds

Background

The Swedish control program for salmonella includes restrictions and on-farm control measures when salmonella is detected in a herd. Required control measures are subsidised by the government. This provides an opportunity to study costs for on-farm salmonella control. The aim of this study was to describe the costs for on-farm salmonella control in Swedish cattle herds and to investigate the effects of herd factors on these costs in dairy herds.

Results

During the 15 years studied there had been a total of 124 restriction periods in 118 cattle herds; 89 dairy herds, 28 specialised fattening herds and three suckler herds. The average costs per herd for on-farm salmonella control was 4.60 million SEK with a median of 1.06 million SEK corresponding to approximately 490 000 and 110 000 EUR. The range was 0.01 to 41 million SEK corresponding to 1080 EUR to 4.44 million EUR per farm. The costs cover measures required in herd-specific control plans, generally measures improving herd hygiene. A mixed linear model was used to investigate associations between herd factors and costs for on-farm salmonella control in dairy herds. Herd size and length of the restriction period were both significantly associated with costs for on-farm control of salmonella with larger herds and longer periods of restrictions leading to higher costs. Serotype detected and administrative changes in the Swedish Board of Agriculture aiming at reducing costs were not associated with costs for on-farm salmonella control.

Conclusions

On-farm control of salmonella in Swedish cattle herds incurred high costs but the costs also varied largely between herds. Larger herds and longer restriction periods increased the costs for on-farm control of salmonella in Swedish dairy herds. This causes concern for future costs for the Swedish salmonella control program as herd sizes are increasing.     

A preliminary trial of the sedation induced by intranasal administration of midazolam alone or in combination with dexmedetomidine and reversal by atipamezole for a short‐term immobilization in pigeons

ObjectiveTo assess the sedative and immobilization effect of intranasal administration (INS) of midazolam (MID) without or with INS dexmedetomidine (DXM), and some physiological changes induced by the drugs. The ability of INS atipamezole to reverse the DXM component was also assessed.Study designProspective ‘blinded’ experimental study.AnimalsIn total, 15 pigeons.MethodsPigeons were sedated by INS MID alone at a dose of 5 mg kg⁻¹ (group MID, n = 6) or in combination with INS DXM at a dose 80 μg kg⁻¹ (group MID-DXM, n = 6). Measurements were made of heart rate (HR), respiratory rate (f_R) and cloacal temperature (CT). The degree of sedation was assessed at 15 minutes prior to, immediately after, and at intervals until 100 minutes after drug administrations. Following MID-DXM, INS atipamezole (250 μg kg⁻¹) was administered and the same indices measured 5 and 10 minutes later.ResultsMID had no effect on HR and f_R, and although CT decreased, it remained within physiological range. MID-DXM caused significant falls in HR, f_R and CT that persisted until the end of sedation. Atipamezole antagonized sedation and cardiorespiratory side effects of MID-DXM within 10 minutes of application. In addition, for MID compared to MID-DXM, the lowest sedation scores [10 (7–14) and 10.5 (5–14) versus 2 (1–4) and 2 (1–5)] were achieved in the 10th and 20th minute versus the 20th and 30th minute of the sedation, respectively.Conclusions and clinical relevanceMID alone, given INS had minimal side effects on vital functions but caused inadequate immobilization of pigeons for restraint in dorsal recumbency. MID-DXM caused an effective degree of immobilization from 20 to 30 minutes after administration, at which time birds tolerated postural changes without resistance. Atipamezole antagonized both side effects and sedation, but complete recovery had not occurred within 10 minutes after its application.     

Impact of redox agents on the extractability of gluten proteins during bread making

The gluten proteins gliadin and glutenin are important for dough and bread characteristics. In the present work, redox agents were used to impact gluten properties and to study gliadin-glutenin interactions in bread making. In control bread making, mixing increased the extractability of glutenin. The level of SDS-extractable glutenin decreased during fermentation and then further in the oven. The levels of extractable alpha- and gamma-gliadin also decreased during bread baking due to gliadin-glutenin polymerization. Neither oxidizing nor reducing agents had an impact on glutenin extractabilities after mixing. The redox additives did not affect omega-gliadin extractabilities during bread making due to their lack of cysteine residues. Potassium iodate (0.82-2.47 micromol/g of protein) and potassium bromate (1.07-3.17 micromol/g of protein) increased both alpha- and gamma-gliadin extractabilities during baking. Increasing concentrations of glutathione (1.15-3.45 micromol/g of protein) decreased levels of extractable alpha- and gamma-gliadins during baking. The work not only demonstrated that, during baking, glutenin and gliadin polymerize through heat-induced sulfhydryl-disulfide exchange reactions, but also demonstrated for the first time that oxidizing agents, besides their effect on dough rheology and hence bread volume, hinder gliadin-glutenin linking during baking, while glutathione increases the degree of covalent gliadin to glutenin linking.     

Suppression of C-hordein synthesis in barley by antisense constructs results in a more balanced amino acid composition

Barley has for feeding purposes a shortage of essential amino acids, especially lysine, threonine, and methionine, and an excess of proline and glutamine. In the present study, we have introduced into barley an antisense construct against C-hordeins, the storage protein with the lowest nutritional quality. SDS-PAGE and reverse phase HPLC revealed a relative reduction in the amounts of C-hordeins and relative increases in the content of the other storage proteins. The five different lines analyzed had lower amounts of proline, glutamic acid/glutamine, and phenylalanine (up to 12%, 6%, and 9% reductions), while the lysine, threonine, and methionine content was increased with up to 16%, 13% and 11%. It is concluded that antisense mediated suppression of C-hordein synthesis may be a promising approach for improving the nutritional value of barley as a feed crop while at the same time reducing the environmental nitrogen load.