<Emphasis Type="Italic">Lupinus albus</Emphasis> Conglutin Gamma Modifies the Gene Expressions of Enzymes Involved in Glucose Hepatic Production <Emphasis Type="Italic">In Vivo</Emphasis>

Lupinus albus seeds contain conglutin gamma (Cγ) protein, which exerts a hypoglycemic effect and positively modifies proteins involved in glucose homeostasis. Cγ could potentially be used to manage patients with impaired glucose metabolism, but there remains a need to evaluate its effects on hepatic glucose production. The present study aimed to analyze G6pc, Fbp1, and Pck1 gene expressions in two experimental animal models of impaired glucose metabolism. We also evaluated hepatic and renal tissue integrity following Cγ treatment. To generate an insulin resistance model, male Wistar rats were provided 30% sucrose solution ad libitum for 20 weeks. To generate a type 2 diabetes model (STZ), five-day-old rats were intraperitoneally injected with streptozotocin (150 mg/kg). Each animal model was randomized into three subgroups that received the following oral treatments daily for one week: 0.9% w/v NaCl (vehicle; IR-Ctrl and STZ-Ctrl); metformin 300 mg/kg (IR-Met and STZ-Met); and Cγ 150 mg/kg (IR-Cγ and STZ-Cγ). Biochemical parameters were assessed pre- and post-treatment using colorimetric or enzymatic methods. We also performed histological analysis of hepatic and renal tissue. G6pc, Fbp1, and Pck1 gene expressions were quantified using real-time PCR. No histological changes were observed in any group. Post-treatment G6pc gene expression was decreased in the IR-Cγ and STZ-Cγ groups. Post-treatment Fbp1 and Pck1 gene expressions were reduced in the IR-Cγ group but increased in STZ-Cγ animals. Overall, these findings suggest that Cγ is involved in reducing hepatic glucose production, mainly through G6pc inhibition in impaired glucose metabolism disorders.     

Prediction of parental combination for introduction of stay-green associated loci in wheat

In wheat, the increase of yield and stability associated traits can be achieved by combining parents containing the stay-green trait and favorable alleles for grain yield. The aim of this work was to analyze the genetic dissimilarity between wheat lines from stay-green and synchronized maturation groups and elite cultivars. Moreover, to propose promising combinations seeking the selection of high-grain yield and high bread-making quality genotypes containing stay-green trait. The experiment was conducted in a randomized block design with three replications in 2003, 2004, and 2005, using sister-lines with the presence and absence of stay-green trait and elite cultivars. Genetic variability exists among wheat strains from the synchronized stay-green maturation group and elite cultivars. Genotypes of maturation group stay-green obtained an average performance superior to the synchronized group. Crosses between stay-green lines and the CEP 29 and BRS 177 cultivars are promising in the selection of genotypes carrying the stay-green trait with high yield and bread-making quality.     

Phytophthora oleae,a new root pathogen of wild olives

Wild olive (Olea europaea subsp. europaea var. sylvestris) is an important component of Mediterranean forests and a key genetic source for olive improvement programmes. Since 2009, a severe decline caused by Phytophthora cryptogea and P. megasperma has been detected in a protected wild olive forest of high ecological value (Dehesa de Abajo, Seville, Spain). In this natural forest, sampling of roots and soil was carried out on 25 wild olives with symptoms in 2014 and 2015. Apart from the already known P. cryptogea A1 and P. megasperma, a third Phytophthora species was consistently isolated from wild olive rootlets with symptoms. These isolates conformed morphologically with the newly described species P. oleae and were confirmed by analysis of their ITS regions and cox1 sequences. Temperature–growth relationships showed a maximum growth at 19.9 °C on carrot agar medium, making it the lowest temperature Phytophthora species infecting wild olive roots. Pathogenicity was confirmed on 1-year-old healthy wild olive seedlings and was similar to the previously known pathogenic phytophthoras. As temperature requirements are quite different, the three Phytophthora species may be active against wild olive roots in different seasons. However, the prevalence of P. oleae infecting wild olives in recent years could be due to its introduction as a new invasive pathogen. The probable invasive nature of P. oleae, together with increasing rain episodes concentrated in short periods frequent in southern Spain, would allow the outbreak of infections in wild olive forests, and also put cultivated olive orchards at risk.     

P0 protein of cotton leafroll dwarf virus-atypical isolate is a weak RNA silencing suppressor and the avirulence determinant that breaks the cotton Cbd gene-based resistance

Cotton blue disease (CBD) is the most important disease present in cotton crops in South America and cotton leafroll dwarf virus (CLRDV) is the causal agent. The disease has been controlled by sowing cotton varieties resistant to CLRDV. However, in the 2009/10 growing season, an outbreak due to an atypical CLRDV isolate (CLRDV-at) occurred in northwest Argentina. Although CLRDV and CLRDV-at genomes are very closely related, the symptoms they produce in cotton plants are quite different. P0 is the most divergent protein between the isolates and in CLRDV is a silencing suppressor protein. This work characterized the silencing suppressor activity of the P0 protein encoded by CLRDV-at (P0^CL-at) and evaluated its role in Cbd-resistance break in cotton plants. It was demonstrated that P0^CL-at, despite having a mutation in the consensus of the F-box-like motif, was able to suppress local RNA silencing, but displayed lower activity than P0^CL. P0^CL and P0^CL-at showed no differences in the interaction with Gossypium hirsutum SKP1 orthologue (GSK1) and Nicotiana benthamiana SKP1 and both P0 proteins triggered destabilization of ARGONAUTE1. However, when the ability to enhance PVX symptoms was evaluated, P0^CL-at was shown to be a weaker pathogenicity factor than P0^CL in N. benthamiana. Interestingly, trans-expressed P0^CL-at enabled CLRDV to systemically infect CBD-resistant plants, and a chimeric CLRDV-P0^CL-at infectious clone succeeded in establishing infection in CBD-resistant cotton varieties with symptoms resembling those produced by CLRDV-at. These results strongly suggest that P0^CL-at is the avirulence (Avr) determinant involved in breaking cotton Cbd gene-based resistance.     

High vegetative compatibility diversity of Cryphonectria parasitica infecting sweet chestnut (Castanea sativa) in Britain indicates multiple pathogen introductions

Chestnut blight, caused by Cryphonectria parasitica, was identified in Devon, UK, in December 2016. Intensive surveys detected the disease at further sites in Devon (seven), Berkshire (one), Dorset (one), Derbyshire (four) and a cluster of eight sites in southeast London. Over 570 survey samples were tested, and 227 were positive for C. parasitica by isolation and real-time PCR. A total of 227 isolates were tested for mating type, and 197 screened for vegetative compatibility group (VCG) and compared with VCGs known from mainland Europe. The same isolates were also screened for the presence of Cryphonectria hypovirus 1 (CHV-1). Eleven VCGs were identified within the UK population. Five corresponded to already known European VCGs but six were unique. The European VCGs mainly came from the Devon, Dorset, Berkshire and Derbyshire disease outbreaks, whilst unique VCGs were almost exclusively from the southeast London cluster. Both mating types were detected, but only one mating type was present at each site, with the exception of a single Devon site. Perithecia of C. parasitica were never observed at any site. CHV-1 was found in seven isolates from three different locations and was always subtype-I, which has limited hypovirulence. Therefore, although CHV-1 is associated with C. parasitica at some outbreaks, it probably has limited impact on virulence. The diversity of VCGs and their distribution at outbreak sites, together with findings of CHV-1, suggests C. parasitica has been introduced to the UK multiple times over at least two decades through international plant trade.     

Connectedness of habitat fragments boosts conservation benefits for butterflies,but only in landscapes with little cropland

Landscape Ecology - Global change pressures (GCPs) imperil species and associated ecosystem functions, but studies investigating interactions of landscape-scale pressures remain scarce. Loss of...     

Climate change will affect the ability of forest management to reduce gaps between current and presettlement forest composition in southeastern Canada

Landscape Ecology - Forest landscapes at the boreal–temperate ecotone have been extensively altered. Reducing the gap between current and presettlement forest conditions through...     

Agriculturally productive yet biodiverse: human benefits and conservation values along a forest-agriculture gradient in Southern Ethiopia

Landscape Ecology - It remains unclear how agricultural landscapes can best serve multiple purposes such as simultaneously maintaining agricultural productivity and conserving biodiversity. Our...     

The scale of landscape effect on seed dispersal depends on both response variables and landscape predictor

Landscape Ecology - Landscape structure can affect seed dispersal, but the spatial scale at which such effect is maximized (scale of effect, SoE) is unknown. We assessed patterns and predictors of...     

Carbon-14 biolabeling of (+)-catechin and proanthocyanidin oligomers in willow tree cuttings.

Proanthocyanidin polymers, oligomers, and the structurally related monomer (+)-catechin were labeled by incorporation of radioactive precursors in shoots of willow tree (Salix caprea L.). [1-(14)C]-Acetate and [U-(14)C]-phenylalanine precursors were fed through the cut stems or petioles of leaves. Optimization of several parameters such as the nature and origin of the plant material, leaf maturity, nature, and quantity of radioactive precursor applied and the duration of metabolism led to incorporation yields of 3.2% and to specific activities of 500 microCi/g. Detailed characterization of the products (polymerization degree, procyanidin/prodelphinidin ratio, specific activities) and purification by chromatography are reported. Some sugars bound to radiolabeled proanthocyanidin polymers were removed by enzymic treatment with a mixture of glycosidases. A radioactive purity close to 100% and specific activities suitable for bioavailability studies were obtained.