Functional markers delimiting a <Emphasis Type="Italic">Medicago</Emphasis> orthologue of pea symbiotic gene <Emphasis Type="Italic">NOD3</Emphasis>

Symbiotic gene mutated in the pea (Pisum sativum L.) line RisfixC is a determinant of the number of symbiotic root nodules. In parallel to a sharp increase in nodule number, its mutational inactivation brings about the insensitivity of nodulation to the ambient nitrate level (Nts trait). Using the established localization to the SYM2-NOD3 region of the pea linkage group I, functional PCR markers were developed for the orthologous region on the chromosome 5 of the model species Medicago truncatula. Owing to the conservation of the binding regions of the designed primers, pea orthologues were successfully amplified with 60% of the primer pairs tested. When applied to a mapping pea population from the cross of the line RisfixC x Afghanistan L1268 (sym2), the new markers allowed to localize the supernodulation mutation within 2.5 cM confidence interval in the pea genome. The placement of the functional markers on the M. truncatula chromosome 5 confined the orthologous gene location to eight overlapping BACs spanning approximately 710 kbp (positions 37,755,678–38,467,472). The narrowed list of the annotated Medicago genes in combination with the published data on their symbiotic and nitrate regulation can be used for the candidate gene identification, together with the requirements imposed by the known function in nodule number initiation and nitrate sensing. In addition, the new markers are applicable for tracking the RisfixC allele in breeding programmes aimed at the improvement of symbiotic performance.     

高效液相色谱法测定肥料中3，4-二甲基吡唑磷酸盐的方法研究

3,4-二甲基吡唑磷酸盐(DMPP)是一种国内外研究较多的新型硝化抑制剂。通过高效液相色谱法外标法,对DMPP及其与多种氮肥原料混配制剂进行含量测定研究。样品前处理条件优化实验结果表明,常温振荡30 min为最佳提取方式。方法在0.1～1000 mg/L范围内表现出很好的线性关系,即y=7.21×103 x+8.08×103(R2=0.9999),且具有较高的精密度和准确度,加标回收率均在97.9%～101.4%之间,随机测定某样品相对标准偏差为0.28%。该方法具有前处理简单、分析速度快、干扰因素少、方法稳定且结果准确等特点,适合DMPP及不同肥料中DMPP含量的测定。     

Identification of oyster-derived hypotensive peptide acting as angiotensin-I-converting enzyme inhibitor

Angiotensin-I-converting enzyme (ACE) plays a crucial role in the crisis of hypertension. Some peptides that originate from protease hydrolysates are known to suppress ACE activity in vitro and in vivo. Here, we investigated whether trypsin hydrolysate of oyster Crassostrea gigas showed hypotensive activity and ACE inhibition. The hydrolysate significantly suppressed systolic blood pressure and ACE activity in spontaneously hypertensive rats following a one-shot oral administration and a long-term feeding experiment lasting 9 weeks. Each hydrolysate from oyster tissue showed ACE inhibitory activity, indicating the hypotensive effect was due to synergism. One potent ACE inhibitory peptide, Asp-Leu-Thr-Asp-Tyr, was identified from the hydrolysate of the striate muscle, and the peptide exhibited hypotensive activity in vivo. Protease digestion analysis suggested that Asp-Tyr could be the real effector of this penta-peptide in vivo.     

Addressing the interplay of poverty and the ecology of landscapes: a Grand Challenge Topic for landscape ecologists?

We argue for the landscape ecology community to adopt the study of poverty and the ecology of landscapes as a Grand Challenge Topic. We present five areas of possible research foci that we believe that landscape ecologists can join with other social and environmental scientists to increase scientific understanding of this pressing issue: (1) scale and poverty; (2) landscape structure and human well-being; (3) social and ecological processes linked to spatial patterns in landscapes; (4) conservation and poverty, and (5) applying the landscape ecologist’s toolkit. A brief set of recommendations for landscape ecologists is also presented. These include the need to utilize broad frameworks that integrate social and ecological variables, build capacity to do this kind of work through the development of strong collaborations of researchers in developed and developing countries, create databases in international locations where extreme poverty exists, and create a new generation of researchers capable of addressing this pressing social and environmental issue.     

Determination of Energy Use Efficiency of some Apple (<Emphasis Type="Italic">Malus x domestica</Emphasis>) Production in Turkey: a Case Study of Eğirdir Region

This research aims to make an analysis of energy use efficiency of apple (‘Starkrimson Delicious’ and ‘Golden Delicious’) production in E?irdir region of Turkey, during the production season of 2012. Production data this research was collected in 2013. In order to determine the energy use efficiency of apple, various surveys have been conducted in 71 apple farms, selected through Simple Random Sampling method, located in E?irdir region of Turkey. The data have been collected through face to face questionnaires and first hand observations. The energy input and output values in apple production have been calculated as 34,703.63 MJ ha^?1 and 95,034 MJ ha^?1, respectively. Energy inputs consist of diesel fuel energy by 29.04?%, chemical fertilizers energy by 24.28?%, machinery energy by 15.70?%, chemical energy by 9.84?%, human labor energy by 8.54?%, electricity energy by 5.63?%, irrigation energy by 3.97?%, farmyard manure energy by 2.88?% and lime energy by 0.12?%. Energy use efficiency, energy productivity, specific energy and net energy in apple production have been calculated as 2.74, 1.16 kg MJ^?1, 0.86 MJ kg^?1 and 60,330.36 MJ ha^?1, respectively. The total energy input consumed has been classified as direct, by 47.17?%, indirect, by 52.83?%, renewable, by 15.38?% and non-renewable, by 74.62?%.     

Origin of rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.) domestication genes

A number of genes that contribute to the domestication traits of cultivated rice have been identified. These include Sh4, Rc, PROG1 and LABA1, which are associated with non-shattering rachis, white pericarp, erect growth and barbless awns, respectively. The mutations giving rise to the “domestication alleles” of these genes are either invariable in cultivated rice, or have variability that is strictly associated with the phenotypic trait. This observation forms the basis to those current rice domestication models that envisage a single origin for the domesticated phenotype. Such models assume that the domestication alleles are absent or rare in wild rice, emerged under cultivation and spread across all rice groups by introgressive hybridization. We examined whole-genome sequencing datasets for wild and cultivated rice to test the former two assumptions. We found that the rc and laba1 alleles occur in wild rice with broad geographical distribution, and reach frequencies as high as 13 and 15%, respectively. These results are in agreement with previous observations of the prog1 and sh4 domestication alleles in wild populations. We also show that the diversity of the genomic regions surrounding the rc, laba1, prog1 and sh4 alleles in wild accessions is greater than that in cultivated rice, suggesting that these alleles emerged prior to domestication. Our findings indicate that the possibility that independent rice groups obtained identical domestication alleles directly from the wild population needs to be considered.     

Hybrids of <Emphasis Type="Italic">Passiflora</Emphasis>: <Emphasis Type="Italic">P. gardneri</Emphasis> versus <Emphasis Type="Italic">P. gibertii,</Emphasis> confirmation of paternity,morphological and cytogenetic characterization

Two new varieties of interspecific hybrids of Passiflora have been developed from the cross between P. gardneri versus P. gibertii, both registered under the Passiflora Society International. Twelve putative hybrids were analyzed. Hybridization was confirmed using RAPD and SSR markers. Primer UBC11 (5′-CCGGCCTTAC-3′) generated informative bands. Primer SSR Pe75 has amplified species-specific fragments and a heterozygote status was observed with two parent bands 300 and 350 bp. The molecular markers generated have been analyzed for the presence or absence of specific informative bands. Based on the morphological characterization, we have identified two hybrid varieties: P. ‘Gabriela’ and P. ‘Bella’. P. ‘Gabriela’ produced flowers in bluish tones, bluish petals on the adaxial and abaxial faces, light blue sepals on the adaxial and light green on the abaxial faces, corona with the base of filaments in intense lilac color and white apex. P. ‘Bella’ produced flowers in lilac tones, intense lilac petals on the adaxial and abaxial faces, dark lilac sepals with whitish edges on the adaxial and light green on the abaxial faces, corona with the base of filaments in intense lilac color and white apex. The cytogenetic analysis verified that the hybrids have the same chromosomal number as the parents (2n = 18); the formation of bivalents between the homeologous chromosomes (n = 9) was observad, leading to regular meiosis, which allows the sexual reproduction and use of these hybrids in breeding programs.     

Dynamics of natural bovine herpesvirus-1 (BoHV-1) infection in a dairy herd

In this study, natural cycling of BoHV-1 infection was investigated in two groups of dairy cattle containing 2120 head. Group 1 comprised 127 animals and they were monitored for BoHV-1 infection virologically and serologically in six consecutive sampling periods. It consisted of naive heifers between 6 and 8 months of age, while in group 2, age, sex and the BoHV-1 serostatus of the animals were disregarded. The animals in group 1 were found to have seroconverted at the second sampling. Results of the serological study showed slight antibody response after natural BoHV-1 infection in the herd and neutralizing titres fell below protective levels in the 6–8 months after the peak. During the 2-year study period, one recurrence was detected after primary infection. Virus isolation studies revealed a cytopathic effect indicative of BoHV-1 in two nasal swabs taken during the fifth sampling period from animals with mild upper respiratory tract symptoms. As the study was carried out under natural conditions, it is not known whether the viruses isolated were from recurrences or re-infections. Data from cross-neutralization tests with herd isolates showed higher antibody response than those with the reference virus. The dynamics of BoHV-1 in both groups were found to be statistically similar.     

Canine model of ischemic stroke with permanent middle cerebral artery occlusion: clinical and histopathological findings

The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients.