Landscape Position and Precipitation Effects on Spatial Variability of Wheat Yield and Grain Protein in Southern Italy

Wheat yield and protein content are spatially variable because of inherent spatial variability of factors affecting the yield at field scale. In Mediterranean environments, yield variability is often caused by the irregular weather pattern, particularly rainfall and by position on the landscape. The objective of this study was to determine the effects of landscape position and rainfall on spatial variability of wheat yield and protein in a rolling terrain field of Southern Italy, and to propose stable management areas through simulation modelling and georesistivity imaging in rolling landscape. The study was carried out in Southern Italy, during 2 years of wheat monoculture; extensive soil properties and in-season plant measurements were measured. This study showed that soil water content was the main factor affecting spatial variation of yield for both years. The interactions between rainfall, topography and soil attributes increase the chances to observe yield variability among years. The principal component analysis demonstrated that for both years, soil water content explained most of the variability. The crop simulation model provided excellent results when compared with measured data with root mean square error of 0.2 t ha⁻¹. The simulated cumulative probability function showed that the model was able to confirm the yield temporal stability of three different zones.     

Offsetting greenhouse gas emissions through biological carbon sequestration in North Eastern Australia

The Kyoto Protocol recognises trees as a sink of carbon and a valid means to offset greenhouse gas emissions and meet internationally agreed emissions targets. This study details biological carbon sequestration rates for common plantation species Araucaria cunninghamii (hoop pine), Eucalyptus cloeziana, Eucalyptus argophloia, Pinus elliottii and Pinus caribaea var hondurensis and individual land areas required in north-eastern Australia to offset greenhouse gas emissions of 1000 t CO₂e. The 3PG simulation model was used to predict above and below-ground estimates of biomass carbon for a range of soil productivity conditions for six representative locations in agricultural regions of north-eastern Australia. The total area required to offset 1000 t CO₂e ranges from 1 ha of E. cloeziana under high productivity conditions in coastal North Queensland to 45 ha of hoop pine in low productivity conditions of inland Central Queensland. These areas must remain planted for a minimum of 30 years to meet the offset of 1000 t CO₂e.     

Seroprevalence of Neospora caninum, Toxoplasma gondii and Sarcocystis sp. in llamas (Lama glama) from Jujuy, Argentina

Llamas (Lama glama) are South American camelids described as intermediate hosts of Neospora caninum, Toxoplasma gondii and Sarcocystis aucheniae. Due to the potential role of these protozoan infections as a cause of economic losses, the aim of this study was to determine the seroprevalence for T. gondii, N. caninum and Sarcocystis sp. in llamas from Argentina. Serum samples from 308 llamas (>2 years old) were collected between 2005 and 2007. A total of 55 farms located in six departments of Jujuy province, Argentina were sampled. Presence of antibodies to N. caninum, T. gondii and Sarcocystis sp. was determined by the indirect fluorescent antibody test (IFAT). For Sarcocystis, 2 different bradyzoites-based antigens were prepared using S. aucheniae and S. cruzi. Sera were tested at dilutions 1:25 and 1:50. Antibodies to N. caninum were found in 4.6% serum samples. Fifty percent of departments and 14.5% of farms had positive animals. Antibodies to T. gondii were found in 30% of samples, distributed in 66% of departments and 43.6% of farms. Antibodies to Sarcocystis sp. were detected in 96% of samples and all departments and farms had positive animals, suggesting frequent contact between llamas and canids. Co-infection with N. caninum, T. gondii and Sarcocystis sp. was also recorded. Low seroprevalence of N. caninum in llamas detected in this study could be related to climatic and geographical conditions that limit cattle breeding activity, reducing the source of infection for definitive hosts. Seroprevalence of T. gondii and the positive animal distribution suggest frequent contamination of grass with felid faeces. In conclusion, this is the first report of combined seroprevalence for N. caninum, T. gondii and Sarcocystis sp. in llamas. Further studies are needed to determine the potential role of these protozoan infections as cause of abortion in Argentina as well as presence of these protozoans in llama meat used for human consumption.     

Variable rate nitrogen fertilizer response in wheat using remote sensing

Nitrogen (N) fertilizer application can lead to increased crop yields but its use efficiency remains generally low which can cause environmental problems related to nitrate leaching as well as nitrous oxide emissions to the atmosphere. The objectives of this study were to: (i) to demonstrate that properly identified variable rates of N fertilizer lead to higher use efficiency and (ii) to evaluate the capability of high spectral resolution satellite to detect within-field crop N response using vegetation indices. This study evaluated three N fertilizer rates (30, 70, and 90 kg N ha^?1) and their response on durum wheat yield across the field. Fertilizer rates were identified through the adoption of the SALUS crop model, in addition to a spatial and temporal analysis of observed wheat grain yield maps. Hand-held and high spectral resolution satellite remote sensing data were collected before and after a spring side dress fertilizer application with FieldSpec, HandHeld Pro^® and RapidEye?, respectively. Twenty-four vegetation indices were compared to evaluate yield performance. Stable zones within the field were defined by analyzing the spatial stability of crop yield of the previous 5 years (Basso et al. in Eur J Agron 51: 5, 2013). The canopy chlorophyll content index (CCCI) discriminated crop N response with an overall accuracy of 71 %, which allowed assessment of the efficiency of the second N application in a spatial context across each management zone. The CCCI derived from remotely sensed images acquired before and after N fertilization proved useful in understanding the spatial response of crops to N fertilization. Spectral data collected with a handheld radiometer on 100 grid points were used to validate spectral data from remote sensing images in the same locations and to verify the efficacy of the correction algorithms of the raw data. This procedure was presented to demonstrate the accuracy of the satellite data when compared to the handheld data. Variable rate N increased nitrogen use efficiency with differences that can have significant implication to the N₂O emissions, nitrate leaching, and farmer’s profit.     

Winter rain and summer ozone: a predictive relationship

Insights from dendrochronology have provided a new seasonal predictor for air pollution meteorology. In the San Francisco Bay Area summer ozone excesses over the federal ozone standard are correlated (correlation coefficient r = .87) with precipitation for the two preceding winters, a factor related to tree-ring width in a precipitation-stressed climate. The hypothesis that reactive hydrocarbon emissions from vegetative biomass affects these ozone excesses was supported by a similar correlation between summer hydrocarbon average maximums and the two-winter precipitation factor, reaching r = .88 at suburban stations. A weak tendency for hot summers to follow wet winters (in 16 years of California data) explains only a minor part of the ozone-rain relationship in multiple correlations.     

Morphological traits of stem to indirect selection of resistance to lodging in Avena sativa L

Journal of Crop Science and Biotechnology - The runout of newly cultivated areas in the world without recurring to the deforestation, demand a necessity to improve yield to sustain a growth...     

Arterial pulse wave propagation velocity in healthy dogs by pulse wave Doppler ultrasound

The aim of this study was to prospectively evaluate the carotid-femoral pulse wave velocity (PWV) values in healthy dogs using pulse wave Doppler ultrasound. A secondary aim was to determine the feasibility of this method and to report the intra- and interobserver reproducibilities of the PWV in conscious dogs. The data were studied in 30 healthy, adult, male (n?=?15) and female (n?=?15) dogs. The time interval marked between the R wave peak of the electrocardiogram and the intersection of the blood flow wave upstroke of the Doppler spectrum with the baseline of zero frequency was determined for the carotid (T₁) and for the femoral (T₂) arteries. The distance covered by the pulse wave (L) was determined. The PWV was then calculated using the following formula: L/T₂ - T₁. The mean values of PWV calculated from the total sample (n?=?30) evaluated were 13.41?±?2.20 m/s. No significant statistical difference was observed for the PWV measurements between males (14.82?±?3.18 m/s) and females (12.64?±?2.45 m/s). The analysis revealed no intra nor interobserver differences. A reasonable reproducibility of the PWV measurements was showed by intraclass correlation coefficients (ICC), and the coefficients of variation (CV). These data demonstrate that noninvasive vascular Doppler analysis is a feasible and reproducible method to determine the carotid-femoral PWV in dogs.     

Naturally Occurring Biventricular Noncompaction in an Adult Domestic Cat

A definitively diagnosed case of left ventricular noncompaction (LVNC) has not been previously reported in a non‐human species. We describe a Maine Coon cross cat with echocardiographically and pathologically documented LVNC. The cat was from a research colony and was heterozygous for the cardiac myosin binding protein C mutation associated with hypertrophic cardiomyopathy (HCM) in Maine Coon cats (A31P). The cat had had echocardiographic examinations performed every 6 months until 6 years of age at which time the cat died of an unrelated cause. Echocardiographic findings consistent with LVNC (moth‐eaten appearance to the inner wall of the mid‐ to apical region of the left ventricle (LV) in cross section and trabeculations of the inner LV wall that communicated with the LV chamber) first were identified at 2 years of age. At necropsy, pathologic findings of LVNC were verified and included the presence of noncompacted myocardium that consisted of endothelial‐lined trabeculations and sinusoids that constituted more than half of the inner part of the LV wall. The right ventricular (RV) wall also was affected. Histopathology identified myofiber disarray, which is characteristic of HCM, although heart weight was normal and LV wall thickness was not increased.