The extent of genetic diversity among Vanilla species: Comparative results for RAPD and ISSR

Vanilla is a large genus of about 110 species in the orchid family (Orchidaceae), including the species Vanilla planifolia from which commercial vanilla flavoring is derived. Since most species of vanilla are considered rare and endangered there is an urgent need to conserve them through genetic analysis and propagation/conservation studies on this crop.The present study investigated the genetic diversity among nine leafy- and leaf-less Vanilla species employing 30 decamer RAPD primers and 10 ISSR primers. The species under study were diverse and displayed a range of variability (0–66% and 0–81% for RAPD and ISSR, respectively). A total of 154 RAPD polymorphic markers (83.24%, h = 0.378) and 93 ISSR polymorphic markers (86.11%, h = 0.363) were used to generate a genetic similarity matrix followed by the cluster analysis. Specific groupings were revealed by each cluster analysis with slight variation between two different markers. Among the nine species studied, V. planifolia, Vanilla aphylla and Vanilla tahitensis revealed very low level of variation within their collections, thus indicating a narrow genetic base. The large genetic distance of Vanilla andamanica from other species suggests its different origin. A close genetic affinity was observed between the pairs V. planifolia, V. tahitensis and Vanilla albida, V. aphylla. These are the first comparative results for RAPD and ISSR reporting inter-relationship among nine cultivated, wild and hybrid Vanilla species.     

Studies on the chiral isomers of fonofos and fonofos oxon: II. In vitro metabolism

The in vitro metabolism of the chiral isomers of fonofos and fonofos oxon in the presence of mouse liver mixed-function oxidase and serum esterase was investigated. The metabolism of ³⁵S-labeled phenyl-(S)_P-fonofos mediated by mixed-function oxidase took place stereoselectively, resulting predominantly in (R)_P-fonofos oxon. Similarly, (R)_P-fonofos was converted to (S)_P-oxon. In each case, however, a significant amount of racemization occurred. Other products were diphenyl disulfide and diphenyl disulfide oxide. In addition to stereospecificity, the oxidative metabolism of (R)_P-fonofos proceeded at a rate faster than that of (S)_P-fonofos. Stereoselective rate differences also were observed in mouse or rat serum-catalzyed degradation of the fonofos oxon enantiomers, the (S)_P isomer being degraded about twofold faster than its enantiomer. The differences in toxicities of the isomers of fonofos and fonofos oxon were consistent with the in vitro metabolism data.     

Chitosan nanoparticles enhance developmental competence of in vitro-matured porcine oocytes

Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus–oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress.     

Nano-calcium carbonate reinforced polypropylene and propylene-ethylene copolymer nanocomposites: Tensile vs. impact behavior

Improvement of both the tensile and impact strength of the same polymeric material has always been a great challenge for the plastic industry. The study focuses on the effect of incorporation of calcium carbonate nanoparticles (0.3 wt% to 15 wt%) into three polypropylene (PP) based matrices viz. PP homopolymer, propylene-ethylene (PP-PE) copolymer and the blend of PP:PP-PE (30:70) to improve their impact behavior without hampering the tensile strength much. A loss in both the tensile and impact properties was observed in PP based nanocomposite. However, PP-PE based nanocomposites showed a significant improvement in impact strength (47 %) at 10 wt% loading with a loss of tensile strength by 22 %. To minimize this loss a blend of PP:PP-PE (30:70) was explored as a matrix. At 10 wt% loading, this matrix showed an improvement of 30 % in impact strength whereas the tensile loss was minimized to 10 %. Further, silane coupling agent which promoted good interfacial adhesion was used for best compositions. The variation of crystalline morphology of the nanocomposites with various formulations was analyzed using differential scanning calorimetry and X-ray diffraction.     

Alteration in important quality traits and antioxidant activities in Brassica oleracea with Ogura cybrid cytoplasm

In vegetable brassicas, cytoplasmic male sterility (CMS) system is the most preferred mechanism for hybrid seed production and Ogura cybrid cytoplasm is the only source used widely. Effects of the alien cybrid cytoplasm on important quality traits need to be understood for their effective use in breeding programme. In analysing 38 Ogura cybrid cytoplasm‐based cauliflower CMS lines, it was revealed that introgression of Ogura cytoplasm resulted in significant alteration in important quality traits. Cupric reducing antioxidant activity and ferric reducing ability of plasma values were increased up to 5–10 times in different genotypes. Among 38 analysed CMS lines, concentration of plant pigments such as anthocyanin, total chlorophylls and ascorbic acid was reduced in 21, 17 and 32 genotypes, respectively. However, the concentration of total carotenoids and β‐carotene was elevated in most of the CMS lines and total carotenoid was increased up to 20 times in the CMS line, Ogu13‐85‐2A. The results indicate the role of nuclear–cytoplasmic interaction and mitochondrial genome in determining concentration of different quality traits.     

Euthanasia of honey-bee colonies: Proposal of a standard method

Honey bees are most often kept for production purposes. Sanitary, regulatory, or zootechnical circumstances may lead the beekeeper or the veterinarian to dispose of a honey-bee colony. Unfortunately and at present, no standard method of euthanasia exists, leaving the door open to many more or less acceptable practices. Based on a short survey of current practices in 8 countries, we list and rank these methods. Although imperfect, the sulfur dioxide technique appears to be the most efficient. We suggest that it should become the reference method to be taught and incorporated into veterinary and regulatory guidelines.     

Prolonged gestation in two Holstein cows: transabdominal ultrasonographic findings in late pregnancy and pathologic findings in the fetuses

Prolonged pregnancy in cattle is a rare condition that is commonly accompanied with fetal adenohypophyseal hypoplasia. The final diagnosis is often challenging as breeding date error remains possible in virtually all situations. In this report, fetal wellbeing assessment is depicted in two Holstein cows suffered from prolonged pregnancy. Transabdominal ultrasonographic findings were compatible with healthy non-stressed fetuses. The clinical and pathologic findings encountered in both fetuses expelled after corticosteroid induction of parturition consisted of adenohypophyseal aplasia and hydronephrosis. Other nervous system anomalies (hydrocephaly or holocephaly) were observed. Tetralogy of Fallot was also found in one calf.