Estimation of genetic diversity in some Iranian wild Prunus subgenus Cerasus accessions using inter-simple sequence repeat (ISSR) markers

As Iran is one of the main origins of Prunus germplasm. In this study, ISSR markers were used for genetic diversity evaluation of 39 accessions of subgenus Cerasus belonging to six species i.e. Prunus avium L., Prunus cerasus L., Prunus mahaleb L., Prunus incana Pall., Prunus microcarpa Boiss., and Prunus brachypetala Boiss.. With 12 ISSR primers, 151 polymorphic bands were detected with polymorphism ratio range of 81.8%–100%. The lowest similarity (0.04) was found between P. avium and P. microcarpa genotypes and the mean of similarity between all genotypes was 0.28. Cluster analysis separated improved cultivars from wild accessions. Improved cherry cultivars and rootstocks were placed closer to the P. avium than the other species. The principal coordinate analysis (PCoA) supported the cluster analysis results. The wild accessions were separated according to their species and collection sites. ISSR markers are useful techniques for genetic diversity evaluation in Prunus subgenus Cerasus.     

Key processes of the nitrogen cycle in an irrigated and a non-irrigated grazed pasture

The paper presents integrated measurements of N fixation, net mineralisation, pasture yield and change in soil mineral N over a 12 month period for dairy pastures on a sandy loam soil in the South East of South Australia. The two adjacent pastures studied were an irrigated perennial white clover-ryegrass and an annual non-irrigated subterranean clover with mixed annual grasses. This produced the most comprehensive mineral N balance reported for grazed pastures, to the authors' knowledge, allowing calculation of gaseous and leaching losses of N (210 kg ha^–1 in the irrigated and paddock and 81 kg ha^–1 in the non irrigated paddock) primarily from urine patches. In both paddocks these losses were about three times the N yield in milk (61 and 28 kg N ha^–1 respectively) and were replenished by biological N fixation (294 and 100 kg N ha^–1). However, mineralisation of soil organic N, excretal N and pasture residues (687 and 438 kg N ha^–1) was the major source of mineral N for cycling and losses. The results demonstrate the enormous impact of pasture management on N fluxes and reinforce the importance of livestock urine on the magnitude of N fluxes including gaseous and leaching losses.     

Genetic and Phenotypic Diversity among Botrytis cinerea Isolates in Iran

Forty-four Botrytis cinerea isolates from different hosts and geographical regions were studied for colony morphology, mycelial growth rate at different temperatures, pathogenicity and molecular diversity. Botrytis cinerea isolates had temperature optima of 20–25°C and isolates showed variation in growth rate at different temperatures. Two morphological types were identified among tested isolates: mycelial and sclerotial. The pathogenicity of isolates was tested on grapevine leaves, and it was revealed that nine of 44 isolates were non-pathogenic and among them seven were of mycelial type. There was no correlation between mycelium growth rate and pathogenicity. Genetic diversity was investigated using nine arbitrary decaprimers. No relationship was found between molecular clusters and geographical region or sampling time; whereas isolates from the same plant host tended to cluster with each other. Seven of nine non-pathogenic isolates were separated from pathogenic ones.     

A Therapeutic Insight of Niacin and Coenzyme Q10 Against Diabetic Encephalopathy in Rats

Diabetes mellitus (DM) is characterized by hyperglycemia due to insulin inactivity or insufficiency with increasing risk of developing specific complications, including retinopathy, nephropathy, neuropathy, and atherosclerosis. The aim of the present study is to evaluate the efficacy of coenzyme Q10 (CoQ10), niacin, as well as their combination in ameliorating brain disorders associated with streptozotocin (STZ)-induced diabetes in rats. Glibenclamide, a reference diabetic drug, and donepezil, an acetylcholine inhibitor drug, were also evaluated. Diabetes was induced by single intraperitoneal injection of STZ (60 mg/kg body weight (b.wt)). One-month diabetic rats were treated with the selected drugs daily for another two consecutive weeks. The evaluation was done through the estimation of the levels of blood glucose, serum insulin, and oxidative stress markers: malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH); neurotransmitters: acetylcholine (Ach) and dopamine (DA); vasoconstrictor indices: intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1(VCAM-1), and angiotensin II (Ang II); and apoptosis markers: tumor necrosis factor-α (TNF-α) and caspase-3 as well as the histopathological picture of the cerebellum region of the brain. The results revealed that the combination of niacin and CoQ10 improved most of the measured parameters with variable degrees. In conclusion, niacin and CoQ10 are promising dietary supplements in the management of diabetic encephalopathy.     

Evaluation of rhizosphere bacterial antagonists for their potential to bioprotect potato (Solanum tuberosum) against bacterial wilt (Ralstonia solanacearum)

Bacterial wilt (Ralstonia solanacearum) is one of the production constraints of potato (Solanum tuberosum). The intent of the study was to evaluate potential of bacterial antagonists to suppress bacterial wilt disease development and evaluate the role of the strains as plant growth-promoting rhizobacteria (PGPR) in potato. One hundred-twenty rhizosphere bacterial isolates were screened against virulent strain of Ralstonia solanacearum PPRC-Rs. After in vitro screening, six antagonistic strains (PFMRI, BS-DFS, PF9, PF20, BC, and BS-wly) with inhibition diameter >11 mm were selected and studied further in the greenhouse, in vivo. During in vivo study, the strains were evaluated for their effect in suppressing disease development in terms of area under disease progress curve (AUDPC) and increasing biomass (plant height and dry weight) of potato. Accordingly, PFMRI, BS-DFS, and PF9, significantly reduced AUDPC by 78.6, 66, and 64.3%, and wilt incidence by 82.7, 66.2, and 65.7%, respectively, compared to the control. During the sole application, the strains significantly (P < 0.0001) increased plant height by 35.6, 45.9, and 45%, and dry matter by 111, 130.4, and 129%, respectively compared to non-bacterized control. In the presence of the pathogen strain PFMRI, BS-DFS, and PF9 increased plant height by 66, 50, and 48.2%, and dry matter by 153.8, 96.8, and 92.5%, respectively compared to the pathogen treated control. Hence, the study shows that PFMRI, BS-DFS, and PF9 strains have potential use in potato bioprotection, as PGPR or in an integrated bacterial wilt management; whose effectiveness under a variety of field conditions should be investigated.     

New synergistic co-culture of Corylus avellana cells and Epicoccum nigrum for paclitaxel production

Journal of Industrial Microbiology & Biotechnology - Paclitaxel is a main impressive chemotherapeutic agent with unique mode of action and broad-spectrum activity against cancers. Hazel...     

Are Early Somatic Embryos of the Norway Spruce (Picea abies (L.) Karst.) Organised?

Background

Somatic embryogenesis in conifer species has great potential for the forestry industry. Hence, a number of methods have been developed for their efficient and rapid propagation through somatic embryogenesis. Although information is available regarding the previous process-mediated generation of embryogenic cells to form somatic embryos, there is a dearth of information in the literature on the detailed structure of these clusters.

Methodology/Principal Findings

The main aim of this study was to provide a more detailed structure of the embryogenic tissue clusters obtained through the in vitro propagation of the Norway spruce (Picea abies (L.) Karst.). We primarily focused on the growth of early somatic embryos (ESEs). The data on ESE growth suggested that there may be clear distinctions between their inner and outer regions. Therefore, we selected ESEs collected on the 56^th day after sub-cultivation to dissect the homogeneity of the ESE clusters. Two colourimetric assays (acetocarmine and fluorescein diacetate/propidium iodide staining) and one metabolic assay based on the use of 2,3,5-triphenyltetrazolium chloride uncovered large differences in the metabolic activity inside the cluster. Next, we performed nuclear magnetic resonance measurements. The ESE cluster seemed to be compactly aggregated during the first four weeks of cultivation; thereafter, the difference between the ¹H nuclei concentration in the inner and outer clusters was more evident. There were clear differences in the visual appearance of embryos from the outer and inner regions. Finally, a cluster was divided into six parts (three each from the inner and the outer regions of the embryo) to determine their growth and viability. The innermost embryos (centripetally towards the cluster centre) could grow after sub-cultivation but exhibited the slowest rate and required the longest time to reach the common growth rate. To confirm our hypothesis on the organisation of the ESE cluster, we investigated the effect of cluster orientation on the cultivation medium and the influence of the change of the cluster’s three-dimensional orientation on its development. Maintaining the same position when transferring ESEs into new cultivation medium seemed to be necessary because changes in the orientation significantly affected ESE growth.

Conclusions and Significance

This work illustrated the possible inner organisation of ESEs. The outer layer of ESEs is formed by individual somatic embryos with high metabolic activity (and with high demands for nutrients, oxygen and water), while an embryonal group is directed outside of the ESE cluster. Somatic embryos with depressed metabolic activity were localised in the inner regions, where these embryonic tissues probably have a very important transport function.