Hirschmanniella pomponiensis n. sp. (Nemata: Pratylenchidae), Parasitic on Bulrush,Scirpus robustus Pursh

A new species of Hirschmanniella was found in bulrush roots; LM and SEM morphological studies revealed that it is distinct from other species in the genus. Therefore, it is designated Hirschmanniella pomponiensis n. sp. Six lips are fused to form a hexagonal labial plate, six inner sensilla encircle the stoma opening, and four cephalic sensilla open in the corners of subdorsal and subventral lips. Cephalic lip region consists of six or seven annuli. The female has incomplete areolation in the lateral field, the intestine overlaps the rectum, the tail tip is pointed and without annulation.     

Meloidogyne californiensis n. sp. (Nemata: Meloidogyninae), Parasitic On Bulrush,Scirpus robustus Pursh

Meloidogyne californiensis n. sp. is described and illustrated from bulrush Scirpus robustus in California. LM and SEM studies revealed that this species differs from other known species in the genus Meloidogyne especially by the prominent posterior cuticular protuberances in the female, the distinct shape of the perineal pattern which is marked by one prominent stria in the perineum, indistinct lateral lines, many broken discontinuous striae on both sides of the arch, and the excretory pore being located posterior to stylet base. Second-stage juveniles 448-628 μm long, stylet length 11-13 μm, styler delicate, with small knobs sloping posteriorly, cephalic region with 2 or 3 annuli, and inflated rectum. Males vary greatly in size (712-1,952 μm), stylet length 18-28 μm (mean 22 μm), cephalic region slightly set off the body with two or three annuli, spear heavy with massive rounded knobs, lateral field marked by four areolated incisures as seen by SEM.     

Effects of salinity and gibberellin on water content,growth and mineral composition of cowpea,calabrese and red radish plants

Salinity had generally little influence on the water content of different parts of cowpea(Vigna sinensis L.), calabrese(Brassica oleracea L. var.botrylis) and red radish(Raphanus salivus L.) plants. Salinity showed a promotive effect on the growth of cowpea, while in calabrese the effect was either promotive or depressive depending upon the concentration of the NaCl, and in red radish plants salinity progressively suppressed growth. Total nitrogen, phosphorus, potassium and sodium contents of cowpea leaves were not affected by salinity treatments, while in calabrese and red radish leaves the contents of N, P and K were generally decreased as the salinity level increased. Gibberellin (GA₃) applied to salt-treated plants had either a stimulatory or inhibitory effect on the growth, water content and contents of N, P, K and Na in the leaves depending upon the plant type, the concentration of GA₃ and level of salinity.     

Ethanol exhibits alpha receptor blocking-like properties in anesthetized rats

The ability of ethanol to reduce alpha-adrenergic receptor-mediated pressor responsiveness in vivo was investigated in chloralose-anesthetized male Sprague-Dawley rats. Catheters were inserted in the jugular vein and the femoral artery of rats for the injection of drugs and the measurement of blood pressure, respectively. Dose-response curves for phenylephrine and norepinephrine were constructed by plotting the change in mean arterial pressure following a bolus dose of the agent against the dose of the pressor agent used. Following construction of an initial dose-response curve, animals were challenged with either a 1 g/kg dose of ethanol or an equivalent volume of saline (iv) and the dose-response curves were repeated. Using a similar protocol, pressor responsiveness was evaluated in animals pretreated with either yohimbine (1 mg/kg) or prazosin (3.9 micrograms/kg), a dose sufficient to produce partial blockade of alpha receptor-mediated pressor responsiveness, and then treated with ethanol. Ethanol produced a partial blockade of alpha receptors when the animals were challenged with either phenylephrine or norepinephrine. This blockade produced by ethanol was shown to be similar to that produced by the receptor blocking agents used in this study. To rule out any nonspecific effects of ethanol in reducing vascular reactivity, some animals were challenged with angiotensin II both before and after treatment with ethanol, yohimbine, or prazosin and after both drugs were administered together. Ethanol, as well as the alpha 1- and alpha 2-adrenergic blocking agents tested failed to have any significant effect on angiotensin II-pressor responsiveness, ruling out any nonspecific effect of ethanol on the vasculature. It is concluded, therefore, that ethanol has alpha receptor blocking-like activity in vivo.     

Suitability of different mite prey for the development of the predatory mite,Phytoseiulus persimilis

Development of the phytoseiid mitePhytoseiulus persimilis Athias-Henriot was studied when fed on three mite species as prey. The tenuipalpid mite,Brevipalpus pulcher (Canestrini & Fanzago), is an unsuitable prey forP. persimilis as predatory larvae reared on any stages developed to the protonymphal stage only. WhenP. persimilis larvae were reared on the eriophyid mite,Eriophyes dioscoridis Soliman & Abou-Awad, only a few developed to adulthood, but failed to oviposit. On the contrary, predatory larvae fed on the tetranychid mite,Tetranychus urticae Koch, matured in a significantly shorter period and resulting females exhibited a high rate of reproduction.     

Possibilities to reduce adverse effects of salinity by indole-3-acetic acid

Salinity caused a consistent reduction in the growth of cowpea plants and water content in their leaves. The total as well as the pigment fractions, except carotenoids, exhibited lower values than those of control plants at almost all salinity levels. With the rise of salinization, the total nitrogen and potassium contents in the leaves were decreased but the sodium content was increased and phosphorus content was not significantly affected as compared with the controls. The application of IAA to salt-treated plants increased the water content in the leaves but it had no effect on the number of leaves and the stem length. The pigment contents in the leaves were either promoted or inhibited with the application of IAA, depending upon the level of salinization. The application of IAA to plants irrigated with water of the highest salinity level was effective in increasing the potassium content in the leaves as compared with the control, but it had no effect on the other mineral elements.     

Response of seeds ofLupinus termis andVicia faba to the interactive effect of salinity and ascorbic acid or pyridoxine

The interactive effect of salinity and presoaking in ascorbic acid or phyridoxine on germination, seedling growth, and some relevant metabolic changes ofLupinus termis andVicia faba seeds were studied. Germination studies indicated that broad bean tolerated NaCl salinity up to 240mM NaCl and lupin to 200mM NaCl. The lengths of roots and shoots and their water content, as well as dry matter yield, remained more or less unchanged up to the level of 80mM NaCl. Salinity induced marked progressive increases of carbohydrates and proline in broad bean and soluble protein in lupin seedlings, irrespective of the salinity level used. The other organic solutes (soluble protein in broad bean and carbohydrates in lupin seedlings) remained more or less unchanged at low and moderate levels of NaCl. However, under the higher salinity levels, in lupin the losses in carbohydrates were accompanied by increases in soluble protein, whereas in broad bean an opposite effect was obtained. The level of 40mM NaCl had a pronounced stimulatory effect on the all the variables studied. Presoaking seeds in either ascorbic acid or pyridoxine counteracted the adverse effects of salinity on germination and seedling growth as well as on some metabolic mechanisms of lupin and broad bean plants. The importance of these processes to the salinity tolerance of broad bean and lupin have been discussed.     

Effects of non-lethal attacks by three phytoseiid species on subsequent development,fecundity and mortality of the two-spotted spider mite

The effects of attack by the three predaceous mite speciesPhytoseiulus persimilis Athias-Henriot,Phytoseius finitimus Ribaga andAmblyseius gossipi Elbadry on the development, reproduction and mortality of the two-spotted spider miteTetranyschus urticae Koch were evaluated after the prey larvae being exposed to attack by these predators for limited periods. Development of the surviving prey immatures was significantly prolonged; this influence was more distinctive when prey larvae were exposed to the predators for a longer period. The number of prey adults which died early was positively correlated with the length of the feeding period allowed to the predators. A substantial reduction in the number of eggs deposited by the prey females was noted, although the oviposition by the prey females was noted, although the oviposition period and adult longivity were not significantly affected.     

Big flies, small repeats: the "Thr-Gly" region of the period gene in Diptera

The region of the clock gene period (per) that encodes a repetitive tract of threonine-glycine (Thr-Gly) pairs has been compared between Dipteran species both within and outside the Drosophilidae. All the non- Drosophilidae sequences in this region are short and present a remarkably stable picture compared to the Drosophilidae, in which the region is much larger and extremely variable, both in size and composition. The accelerated evolution in the repetitive region of the Drosophilidae appears to be mainly due to an expansion of two ancestral repeats, one encoding a Thr-Gly dipeptide and the other a pentapeptide rich in serine, glycine, and asparagine or threonine. In some drosophilids the expansion involves a duplication of the pentapeptide sequence, but in Drosophila pseudoobscura both the dipeptide and the pentapeptide repeats are present in larger numbers. In the nondrosophilids, however, the pentapeptide sequence is represented by one copy and the dipeptide by two copies. These observations fulfill some of the predictions of recent theoretical models that have simulated the evolution of repetitive sequences.      

The Potential Efficacy of Glycyrrhizic Acid and Its Nanostructure Against Brown Rot of Peach fruits

Production of peaches (Prunus persica (L.) Batsch) for both local market and export is increasing each year in Egypt. Brown rot disease, caused by Monilinia laxa and Monilinia fructigena, is considered one of the most important postharvest rots affecting peaches in Egypt and economic losses are increasing. Antifungal activity of glycyrrhizic acid nanoparticles (GA-NPs) and glycyrrhizic acid (GA) at 0.2 and 0.4 mmol/L was investigated as a control for both these brown rot pathogens on peach fruits in both in vitro and in vivo studies. In the in vitro studies, GA-NPs were the most effective as shown by the ability to decrease linear growth of both brown rot pathogens in potato dextrose agar (PDA) amended with 0.4 mmol/L GA-NPs. Micrographs of M. fructigena exposed to 0.4 mmol/LGA showed mycelial deformations, nodule formation, detachment of the cell wall, shrinkage and inhomogeneous cytoplasmic materials with large vacuoles. Mycelium of M. laxa exposed to 0.4 mmol/ LGA-NPs resulted in thinner and distorted hyphae, nodule formation, cell wall thinning, and swellings. The GANPs and GA treatments improved fruit quality by maintaining firmness and total soluble solids (TSS). GA-NPs were more effective in decreasing decay incidence than their bulk material. The 0.4 mmol/L GA-NPs completely inhibited the disease on naturally infected peach fruits for both seasons of 2018 and 2019. Furthermore, 0.4 mmol/L GA-NPs reduced the disease incidence in inoculated fruits by 95 (M. laxa) and 88% (M. fructigena) in 2018 season and 96 (M. laxa) and 85% (M. fructigena) in 2019 season. In conclusion, GA-NPs could enhance the resistance of peaches against brown rot caused by M. laxa and M. fructigena.