Germplasm enhancement with wild tuber-bearing species: introgression of PVY resistance and high dry matter content fromSolanum berthaultii, S. gourlayi, S. tarijense andS. vernei

Summary The narrow genetic base of the cultivated potato is a severe constraint for potato breeding. Wild tuber-bearing species constitute an important source of genes for resistance to diseases and pests as well as abiotic factors. Seven interspecific hybrid populations were generated from crosses between diploidTuberosum clones and four wild species:Solanum berthaultii, S. gourlayi, S. tarijense andS. vernei, and evaluated in a field experiment in Burgos (Spain) as a way to broaden the genetic base of the cultivated potato. Good tuberization ability and great variability for yield within the different families were detected. Hybridization with the wild species resulted in high levels of PVY resistance inS. berthaultii andS. vernei hybrids and a large increase of dry matter content in all populations except theS. berthaultii hybrids.     

Late Pleistocene ‐ Holocene palaeosols in the north of Sonora,Mexico: chronostratigraphy,pedogenesis and implications for environmental history

Red palaeosols of the late Pleistocene‐early Holocene, both buried and non‐buried, were studied recently in Sonora (NW Mexico) to reconstruct their pedogenesis as well as the palaeoenvironmental conditions. The alluvial palaeosol‐sedimentary sequence of the La Playa archaeological site is a key locality for the buried San Rafael palaeosol, which exhibits a 2Ah‐2Bw‐2BCk‐3Bgk profile and was defined as a Chromic Cambisol. Radiocarbon dates from pedogenic carbonates and charcoal set the soil formation interval between > 18 000 and 4300 calibrated years before present (cal. year BP). Micro‐morphological observations together with profile distribution of clay, carbonates, organic carbon, pedogenic iron oxides and rock magnetic properties indicated a strong eluvial‐illuvial redistribution of carbonates, moderate silicate weathering and gleying in the lower horizon. Although this soil was much more developed than the overlying syn‐sedimentary late Holocene Fluvisols, clay mineral composition and stable carbon isotope signatures of humus and carbonates were similar in both soils. We suggest that pedogenesis of the San Rafael palaeosol took place under a slightly more humid climate and relative geomorphic stability. This agrees with the regional palaeoclimate reconstruction, which indicates a moister climate during the Late Wisconsin glaciation (MIS 2). An abrupt termination of the San Rafael pedogenesis marked by disturbance and aridization features in the Ap horizon of the palaeosol could be linked to a global drought around 4200 years cal. year BP. Surface Chromic Cambisols in northern Sonora show similar pedogenetic characteristics to the buried red palaeosols of La Playa. They appear to be a relict component of the present day soil mantle.     

Proinflammatory cytokines and CD14 expression in mammary tissue of cows following intramammary inoculation of Panax ginseng at drying off

The lack of efficacy of conventional strategies for the maintenance of healthy udders in domestic cattle has prompted studies on the use of immunomodulators or biological response modifiers (BRM) for this purpose. These compounds are agents that modify the host's response to pathogens leading to beneficial effects on disease outcome. The objective of this study was to evaluate the effects of a single intramammary infusion of Panax ginseng (GS) extract on the amount of pro-inflammatory cytokines and the number of monocytes/macrophages present in bovine mammary tissues at drying off. Eight mammary quarters from six nonpregnant cows in late lactation were infused with 10 mL of GS (3mg/mL), six quarters were treated with 10 mL of placebo (vehicle alone) and six quarters were maintained as uninoculated controls. The analyses of tumor necrosis factor-alpha (TNF-α) by immunohistochemistry revealed that the production of this proinflammatory cytokine significantly increased (P<0.05) in the inoculated mammary glands of cows following BRM inoculation, whereas the interleukin-1 alpha (IL-1α) and IL-6 staining area was not affected by BRM treatment. The number of monocytes/macrophages detected with CD14 antibody was significantly higher (P<0.05) in BRM-treated quarters than in placebo and uninoculated control quarters. These results indicated an immunomodulator potential of the BRM used. The beneficial effect of the extract could be used as alternative therapy in the control of mastitis at drying off, either alone or in conjunction with dry cow antibiotic therapy.     

Mycoparasitic Trichoderma isolates as a biocontrol agent against Valsa ceratosperma,the causal agent of apple valsa canker

European Journal of Plant Pathology - Apple valsa canker, caused by the fungus Valsa ceratosperma, is one of the most destructive diseases of this crop. Conventional fungicide treatments are not...     

Study of Red Wine Neuroprotection on Astrocytes

Phenolic composition of wine depends not only on the grape variety from which it is made, but on some external factors such as winemaking technology. Red wine possesses the most antioxidant effect because of its high polyphenolic content. The aim of this work is to study for the first time, the neuroprotective activity of four monovarietal Spanish red wines (Merlot (ME), Tempranillo (T), Garnacha (G) and Cabernet-Sauvignon (CS)) through its antioxidant ability, and to relate this neuroprotection to its polyphenolic composition, if possible. The wine effect on neuroprotection was studied through its effect as free radical scavenger against FeSO₄, H₂O₂ and FeSO₄ + H₂O₂. Effect on cell survival was determined by 3(4,5-dimethyltiazol-2-il)-2,5-diphenyltetrazolium reduction assay (MTT) and lactate dehydrogenase (LDH) release assay on astrocytes cultures. Results showed that most of the studied wine varieties induced neuroprotection through their antioxidant ability in astrocytes, Merlot being the most active; this variety is especially rich in phenolic compounds, mainly catechins and oligomeric proanthocyanidins. Our results show that red wine exerts a protection against oxidative stress generated by different toxic agents and that the observed neuroprotective activity is related to their polyphenolic content.     

Tropical alluvial forest fragmentation in the eastern lowlands of Colombia (1939–1997)

Alluvial forests are under high pressure from human activities because of their value as agricultural, wildlife, timber and recreational land. Despite this, spatial patterns of alluvial forest deforestation are not well known. We studied forest alterations in a 2800 ha alluvial ecosystem using aerial photographs. During the study period (1939–1997), forests with canopy heights greater than 15 m (high canopy mature forest; HCM forest) decreased by 70·4 per cent while forests with canopy heights less than 15 m (low canopy mature forest; LCM forest) forests decreased by 51 per cent, producing a highly fragmented landscape. Factors responsible for forest change included human activities and river dynamics. Although most of the deforestation was related to human disturbance, almost 27 per cent of forest losses were due to channel migration of the Meta River. HCM forests were the most affected land cover since they are easily accessed, viable for logging and occurred on fertile soils, which are valuable for agriculture. LCM forests were less affected since their soil fertilities and inundation regimes were unfavourable to human uses, and thus, less prone to anthropogenic disturbances. Copyright © 2006 John Wiley & Sons, Ltd.     

Immunologic and genetic characterization of S180, a cell line of murine origin capable of growing in different inbred strains of mice

Some of the immunologic and genetic properties of the cell line S180 have been examined. These cells grew without restrictions in the peritoneal cavity of different inbred strains of mice and invariably killed the animals. With Northern blots it was demonstrated that S180 cells contained class I mRNAs but failed to transcribe B2m genes. However, under experimental conditions, a protective humoral immune response mediated by cytotoxic antibodies and complement against S180 cells was obtained through non-H-2 antigens in C57BL/6J mice.     

Estimation of daily milk yield of Nellore cows grazing tropical pastures

Beef cows’ milk yield is typically determined by measuring milk yield once daily and then doubling this value to estimate daily production. However, it is not known whether this is accurate. Thus, we aimed to determine the association between morning and afternoon milk yield in grazing Nellore cows. Eighty Nellore cows were used, with initial weight of 516.0?±?1.0 kg. The experiment was a completely randomized factorial scheme, with 20 replications and four treatments (i.e., +?or ??pre-partum supplementation in combination with +?or ??post-partum supplementation): PRMM—1 kg of supplement/cow/day for 90 days pre-partum; MMPS—1 kg of supplement/cow/day for 90 days post-partum; PRPS—1 kg of supplement/cow/day for 90 days pre-partum and 90 days post-partum; and MM—only mineral mix ad libitum during pre- and post-partum. Milk was sampled on days 45, 135, and 225 post-partum (early, middle, and late lactation, respectively). No effects were observed of pre- and post-partum supplementation on milk yield (P?>?0.05). The afternoon/morning proportion of 0.45 in the early third of lactation was higher than other stages, which had a proportion of 0.41 (P?<?0.05). Post-partum supplementation increased milk protein in the morning and afternoon milking (P?<?0.05). There was also no effect of pre- and post-partum supplementation on afternoon-morning proportion other milk components (P?>?0.05). We conclude that estimating daily milk production of grazing beef cattle by multiplying a once daily milking amount times two is not accurate. Under the conditions of this study, proportion of total daily production represented by the ratio of afternoon/morning milking was 0.45 in early lactation (first third) and 0.41 in mid- and late lactation.     

Effect of marine by‐product meals on hen egg production parameters,yolk lipid composition and sensory quality

The effect of including 5% marine by‐product meals in feeds of laying hens on egg production, composition and sensory characteristics was tested. Marine by‐product meals were prepared using two methods: (i) cooking (100°C/10 min) followed by drying (60°C/24 hr) or (ii) grinding followed by drying. The raw materials used for meal production were scallop or squid viscera, shrimp heads or whole mackerel. A total of 108 laying hens were allocated to nine diet treatments; one control diet (corn and soya bean based) and eight experimental diets, containing 95% of the control feed and 5% of the experimental meal for three weeks. Daily intake was higher in hens fed the dried mackerel and cooked shrimp meals. All the experimental treatments showed significantly higher concentration of n‐3 HUFA in yolk reserves and phospholipids compared to the control (0.12–0.13 g per 100 g), especially those with scallop or squid prepared by both methods (0.53–0.95 g per 100 g). Scallop, squid and shrimp meal inclusion in the feed produced eggs with more astaxanthin (0.22 mg per 100 g) while this carotenoid was absent in the control and mackerel treatments. Visual evaluation of raw yolk colour increased with the inclusion of marine by‐product meals with higher values in hens fed shrimp heads (13), followed by scallop viscera (11), squid viscera (9), and with similar values for mackerel and control (4). The taste, aroma, texture and colour of cooked eggs from different treatments were not statically different when evaluated by a panel of 60 untrained people. These results suggest that meals from marine by‐products are a better alternative for improving egg yolk composition by increasing n‐3 HUFA when compared to fishmeal as they also increase astaxanthin and yolk pigmentation without affecting egg sensory characteristics.