Influence of climatic conditions,topography and soil attributes on the spatial distribution of site productivity index of the species rich forests of Jalisco,Mexico

This paper presents an approach based on field data to model the spatial distribution of the site productivity index （SPI） of the diverse forest types in Jalisco, Mexico and the response in SPI to site and cli-matic conditions. A linear regression model was constructed to test the hypothesis that site and climate variables can be used to predict the SPI of the major forest types in Jalisco. SPI varied significantly with topog-raphy （elevation, aspect and slope）, soil attributes （pH, sand and silt）, climate （temperature and precipitation zones） and forest type. The most important variable in the model was forest type, which accounted for 35% of the variability in SPI. Temperature and precipitation accounted for 8 to 9% of the variability in SPI while the soil attributes accounted for less than 4% of the variability observed in SPI. No significant differences were detected between the observed and predicted SPI for the individual forest types. The linear regression model was used to develop maps of the spatial variability in predicted SPI for the individual forest types in the state. The spatial site productivity models developed in this study provides a basis for understanding the complex relationship that exists between forest productivity and site and climatic conditions in the state. Findings of this study will assist resource managers in making cost-effective decisions about the management of individual forest types in the state of Jalisco, Mexico.     

Serological Survey of Veterinarians to Assess the Zoonotic Potential of Three Emerging Swine Diseases in Mexico

We conducted an immunological assay of blood samples taken from 85 swine‐specialist veterinarians attending the Congress of the Mexican Association of Swine Specialist Veterinarians in Mexico in 2011. Serum samples were assayed for Porcine rubulavirus (PorPV), Encephalomyocarditis virus (EMCV) and Leptospira spp. antibodies. Using a hemagglutination inhibition test, we registered 2.3% and 27% seropositivity for PorPV and EMCV, respectively. Using viral neutralization tests, we registered 5.8% and 47% seropositivity for PorPV and EMCV, respectively. For Leptospira spp., we registered a seropositivity of 38.8%. The variables (sex, age, years of exposure, number of visited farms, biosecurity level and region) showed no significant effect (P > 0.05) on the seropositivity for EMCV, PorPV and Leptospira spp. except for number of visited farms on HI seropositivity for EMCV (P < 0.05; odds ratio: 1.38). The data obtained provide information on the epidemiology of emerging diseases with zoonotic potential in occupational risk groups.     

Combining resistance to potato leafroll virus (PLRV) with immunity to potato viruses X and Y (PVX and PVY)

Summary Degeneration of seed tubers caused by viruses is a major constraint to potato cultivation in many warm tropical areas. Cultivars resistant to the most important viruses present a promising solution to such a problem. In a breeding study conducted at the International Potato Center (CIP), ten cultivars resistant to PLRV were crossed to five clones immune to PVX and PVY, as well as to a susceptible control. The resulting progenies were screened for PVX and PVY immunity. Afterwards, the resistant genotypes were fieldexposed to a PLRV-viruliferous aphid population. One tuber was harvested from each plant and used to assess, using ELISA serology, the presence of leafroll virus. The cultivars Serrana and Pentland Crown gave the best progenies in terms of percentage of healthy plants, with values of 47.4 and 33.3 respectively. The presence of joint infection of PLRV and PVY or PVX in the progenies of the susceptible control resulted in an increased susceptibility to leafroll.     

Breeding effects on sensitivity of barley grain weight and quality to events of high temperature during grain filling

Monogenic inheritance and linkage were established on the basis of F₁ observations and analysis of 13,498 plants in 42 crosses for leaf colour, 7046 plants in 27 crosses for plant pubescence, 1926 plants in 8 crosses for number of leaflets per leaf, and 3182 plants in 12 crosses for plant height under field conditions. Normal green colour of foliage was found to be dominant over light green, pubescent plant over glabrous, high number of leaflets per leaf over low number of leaflets, and tall plant over dwarf. Linkage was estimated from joint segregation analysis, taking two characters at a time in all possible combinations as significant χ² values were recorded for these genes. Gene symbols Gl, Pub, Ph, and Hl are proposed for these four traits, respectively. The genes are arranged in the order of Ph-Gl-Pub-Hl with the map distances of 21.1, 28.9, and 17.5 cM between them. This short sequence of four linked genes spanning over 37.2 cM has been called Linkage Group 2 of lentil.     

The great tumaco, Colombia earthquake of 12 december 1979

Southwestern Colombia and northern Ecuador were shaken by a shal-low-focus earthquake on 12 December 1979. The magnitude 8 shock, located near Tumaco, Colombia, was the largest in northwestern South America since 1942 and had been forecast to fill a seismic gap. Thrust faulting occurred on a 280- by 130-kilometer rectangular patch of a subduction zone that dips east beneath the Pacific coast of Colombia. A 200-kilometer stretch of the coast tectonically subsided as much as 1.6 meters; uplift occurred offshore on the continental slope. A tsunami swept inland immediately after the earthquake. Ground shaking (intensity VI to IX) caused many buildings to collapse and generated liquefaction in sand fills and in Holocene beach, lagoonal, and fluvial deposits.     

Detection and characterisation of Shiga toxin-producing Escherichia coli other than Escherichia coli O157:H7 in wild ruminants

Shiga toxin-producing Escherichia coli (STEC) are an important group of emerging pathogens, with ruminants recognised as their main natural reservoir. The aim of this work was to establish the prevalence of non-O157 STEC in free-ranging wild ruminants in the Extremadura region of Spain and to characterise them phenogenotypically. Faecal samples were collected from 243 wild ruminants, including Cervus elaphus, Capreolus capreolus, Dama dama and Ovis musimon and were examined for STEC using both phenotypic (Vero cells) and genotypic (PCR and PFGE) methods.Shiga toxin-producing Escherichia coli were isolated from 58 (23.9%) of the samples and a total of 65 isolates were characterised. A PCR method indicated that 11 (16.9%) strains carried the stx₁ gene, 44 (67.7%) carried the stx₂ gene and 10 (15.4%) carried both these genes. The ehxA gene was detected in 37 (57%) of the isolates but none contained either the eae or saa genes. The isolates were from a total of 12 ‘O’ serogroups, although 80% were restricted to the O2, O8, O128, O146, O166 and O174 serogroups. The most commonly isolated STEC bacteria, which were from the O146 serogroup, exhibited a high degree of polymorphism as indicated by PFGE. Shiga toxin-producing Escherichia coli isolates of serogroups O20, O25, O166, O171, O174 and O176 had not previously been found in wild ruminants. This is the first study to confirm that wild ruminants in Spain are a reservoir of STEC and are thus a potential source of human infection.     

Incidence of abortions caused by leptospirosis in sheep and goats in Spain

From 1970 to 1985, 973 outbreaks of abortion in sheep and 262 outbreaks of abortion in goats from southern Spain were studied. Of these, 1.7 and 2.6% respectively were caused by leptospiras, chiefly by the serovar pomona (11 flocks of sheep, 64.7%, and six herds of goats, 75.0%) and in a lower proportion the serovars sejroe (three flocks of sheep 17.6%, and one herd of goats, 12.5%), icterohaemorrhagiae (two and one outbreaks respectively) and grippotyphosa in one ovine flock (5.8%). The mean rates of attach (X + SD) of abortions by leptospirosis have been estimated as 16.9 + 6.5% in ovine outbreaks and 20.7 + 8.3% among goats.