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Impacts of six ethanolic plant extracts on feeding and developmental time of Tetranychus urticae
No full textDevelopment in chemical pesticides and the problems caused by the indiscriminate use of them, has led to the rise of new ways to control pests. The use of plant-based compounds is a proposed method, because they have far less destructive effects on the environment. Study of all aspects and effects of a botanical insecticide is required, such as feed rate which is assessed on Tetranychus urticae Koch. Individual leaves were sprayed with 6 ethanolic extracts (Aloe vera, Melia azedarach, Calendula officinalis, Syzygium aromaticum, Peganum harmala and Juglans regia) with concentration of 4 mg.mL−1, and then starved mites (larvae) were laid on them. Feeding rate was determined by the color of chlorophyll inside the body. Finally, M. azedarach, A. vera, P. harmala and C. officinalis decreased the feeding rate, specially M. azedarach extract caused almost 50% decrease in the first day, 30% in the second day and 20% in the third day. According to the last experiment, the mean of total developmental time of M. azedarach treatment was significantly longer than control treatment
To study family Eulophidae (Hymenoptera: Chalcidoidea) of northwestern Iran
No full textThis paper deals with the faunistic surveys on Eulophidae (Hymenoptera, Chalcidoidea) of northwestern Iran. In total 17 species from 12 genera and 3 subfamilies (Entedoninae, Eulophinae, Tetrastichinae) were collected and identified. Chrysocharis pubens Delucchi, Pediobius eubius (Walker), Dicladocerus westwoodi Westwood, Miotropis unipuncta (Nees), Sympiesis viridula (Thomson), Aprostocetus pygmaeus (Zetterstedt) and Neotrichoporoides viridimaculatus (Fullaway) are new records for the fauna of Iran
Muscle damage after low-intensity eccentric contractions with blood flow restriction
No full textDiscrepancies exist whether blood flow restriction (BFR) exacerbates exercise-induced muscle damage (EIMD). This study compared low-intensity eccentric contractions of the elbow flexors with and without BFR for changes in indirect markers of muscle damage. Nine untrained young men (18–26 y) performed low-intensity (30% 1RM) eccentric contractions (2-s) of the elbow flexors with one arm assigned to BFR and the other arm without BFR. EIMD markers of maximum voluntary isometric contraction (MVC) torque, range of motion (ROM), upper arm circumference, muscle thickness and muscle soreness were measured before, immediately after, 1, 2, 3, and 4 days after exercise. Electromyography (EMG) amplitude of the biceps brachii and brachioradialis were recorded during exercise. EMG amplitude was not significantly different between arms and did not significantly change from set 1 to set 4 for the biceps brachii but increased for the brachioradialis (p ≤ 0.05, 12.0% to 14.5%) when the conditions were combined. No significant differences in the changes in any variables were found between arms. MVC torque decreased 7% immediately post-exercise (p ≤ 0.05), but no significant changes in ROM, circumference, muscle thickness and muscle soreness were found. These results show that BFR does not affect EIMD by low-intensity eccentric contractions
Role of expectations and pleasantness of essential oils in their acute effects
No full textEffects of inhaled essential oils (EOs) cannot be explained by pharmacological mechanisms alone. The study aimed to investigate the effects of pleasantness of and expectancies evoked by EOs. A double-blind experiment with a within-subject design was carried out with the participation of 33 volunteering adults (15.2% male; mean age 37.7 ± 10.90 years). Participants were exposed to three EOs (rosemary, lavender, and eucalyptus) for three minutes in a quasi-random order, expectations were simply assessed prior to exposure. Subjective (perceived) changes in alertness, heart rate (HR), and blood pressure (BP), and objective changes in HR, BP, and indices of heart rate variability were recorded. Significant group-level differences in changes in alertness and no differences for the cardiovascular variables were found. Participants’ expectations predicted changes in alertness in the case of rosemary and lavender oils but had no impact on cardiovascular variables. EOs’ pleasantness had no effect on any assessed variable. Perceived changes in BP and HR were not related to the respective objective changes but were connected to perceived changes in alertness. Expectancies play an important role in the subjective effects of inhaled EOs. Perceived subjective changes are used to estimate changes in non-conscious (e.g., visceral) states
Age-related site-specific muscle loss in the thigh and zigzag walking performance in older men and women
No full textTo investigate the relationships between site-specific muscle loss in the thigh, muscle quality and zigzag walking performance, 40 men and 41 women aged 65–79 years had muscle thickness (MTH) measured by ultrasound at nine sites on the anterior and posterior aspects of the body. Skeletal muscle mass (SM) was estimated from an ultrasoundderived prediction equation. Site-specific thigh sarcopenia was calculated using ultrasound-measured MTH at the anterior/posterior aspects of the thigh (AP-MTH ratio). Zigzag walking time (ZWT) and maximum isometric knee extension (KE) and flexion (KF) torques were measured. Muscle quality (torque/thigh SM) and knee joint strength index (torque/body mass) were calculated. There were no significant correlations between SM index and ZWT. However, AP-MTH ratio was inversely correlated (P < 0.05) to ZWT in men (r = −0.335) and women (r = −0.309). ZWT was also inversely correlated (P < 0.05) to KE-strength index in both sexes (men, r = −0.328; women, r = −0.372). Similarly, ZWT was correlated to KF-strength index (r = −0.497) and muscle quality (r = −0.322) in women, but not in men. After adjusting for age, height and body mass, AP-MTH ratio was inversely correlated to ZWT in men (r = −0.325) and tended to be correlated to ZWT in women (r = −0.263). Zigzag walking performance may be associated with site-specific thigh sarcopenia in older men and women
Preliminary Study on the Physiological Characteristics of Transgenic Wheat with Maize C<sub>4</sub>-pepc Gene in Field Conditions
No full textTo explore the physiological characteristics of the pepc gene in transgenic wheat (Triticum aestivum) plants, PEPC activities in various organs of T3 plants were analyzed at Feekes 6.0, Feekes 10.3 and Feekes 11.1, and compared to control, untransformed wheat cultivar Zhoumai 19. Net photosynthetic rates (Pn) in leaves were also measured at the same stages. At Feekes 11.1, both transgenic and control plants were treated with DCDP. Yield traits were surveyed after harvest. The results indicated that Pn and PEPC activity in the flag leaf of transgenic wheat were significantly higher than those of the control at different stages. At Feekes 10.3, Pn reached the highest value at 28.2 μmol m−2 s−1 and PEPC activity reached the highest value at 104.6 μmol h−1 mg−1. Both factors significantly increased by 21% compared to the control at Feekes 11.1. PEPC activity in the flag leaf of transgenic plants was significantly higher than that of non-leaf organs. Pn of transgenic plants was greatly reduced after DCDP treatment. In the flag leaf of transgenic wheat, Pn was significantly correlated to PEPC activities at 0.01 probability level with a correlation coefficient of 0.8957**. The yield traits of transgenic line 1-27-3, such as 1000-grain weight, single spike weight and harvest index were higher than those of the control. Additionally, the spike weight of 1-27-3 showed an increase of approximately 9.5% compared to the control. These results indicated that the expression of maize (Zea mays) pepc gene was different across various organs of transgenic wheat and across every growth stage. Therefore, we conclude that introducing maize pepc gene into wheat plants can increase their Pn and improve production
Involvement of Nitric Oxide in the Russian Wheat Aphid Resistance Response of Wheat
No full textThe involvement of nitric oxide (NO) in the Russian wheat aphid (RWA), Diuraphis noxia (Kurdjumov), resistance response of wheat (Triticum aestivum L.) was investigated. Resistant (cv. Tugela DN) and near isogenic susceptible (cv. Tugela) wheat plants grown under green-house conditions were used. Russian wheat aphid infestation induced an early accumulation of NO to a higher level in the resistant than susceptible plants. Nitric oxide accumulation corresponded with increased nitrate reductase (NR, EC 1.6.6.1) and nitrite reductase (NiR, EC 1.7.7.1) activities, suggesting a possible association with NO production. Inhibition studies confirmed the involvement of NR in NO production during the RWA resistance response. The use of a NO donor or NR inhibitor revealed that NO could act as another early signal for induction of the secondary defence enzymes, intercellular β-1,3-glucanase and peroxidase
The abiotic stress response and adaptation of triticale — A review
No full textAfter a decade of genetic manipulation and improvement, triticale stand out as a crop of high biomass and grain yield potential which generally surpass that of wheat. Its high productivity is most likely derived from high rates of carbon assimilation linked to stomatal physiology and probably low respiration rate. Being a derivative of rye, triticale has always been assumed to be relatively resistant to abiotic stress. The last review of triticale adaptation to abiotic stress as published by Jessop (1996) pointed at its general and specific fitness to harsh growing conditions. This review as based on additional data published in the last 20 years indicates that triticale retain good to excellent adaptation to conditions of limited water supply and problem soils which involve salinity, low pH, defined mineral toxicities and deficiencies and waterlogging. Despite the understandable expectations, freezing tolerance of triticale was not found to be up to the level of rye. The freezing tolerance of the rye complement in triticale is inhibited by unknown factors on the wheat parent genome. Any given triticale cultivar or selection cannot be taken a priori as being stress resistant. Research has repeatedly shown that triticale presented large genetic diversity for abiotic stress resistance and most likely this diversity has not yet been fully explored due to the very limited research and the small studied sample of the potential triticale germplasm. Triticale is a valuable stress tolerant cereal on its own accord and a potential genetic resource for breeding winter and spring cereals. Because of its high productivity and resilience it might become as important as wheat or better on a global scale if its grain technological quality will be improved to the level of wheat
Linkage mapping for grain iron and zinc content in F<sub>2</sub> population derived from the cross between PAU201 and Palman 579 in rice (Oryza sativa L.)
No full textMolecular markers provide novel tools for linkage mapping of QTLs of target traits and can greatly enhance the efficacy of breeding programs to improve mineral (iron and zinc) density in rice. A F2 population derived from the cross between high-yielding (PAU201) and iron-rich (Palman 579) indica rice varieties displayed large variation for various physio-morphological traits including grain yield per plant and iron and zinc contents. Transgressive segregation for grain iron and/or zinc contents was noticed in some F2 individuals with one of the F2 plants having exceptionally higher iron (475.4 μg/g) as well as zinc (157.4 μg/g) contents. Grain iron content showed significant positive correlation (r = 0.523) with grain zinc content indicating the feasibility of improving iron and zinc levels simultaneously in rice grain. Two parental rice varieties displayed polymorphism at 76 of the 100 SSR loci, which were used to map the QTLs associated with mineral content in grains. Composite interval mapping (CIM) analysis by Win QTL cartographer 2.5 revealed a total of eleven QTLs for mineral content (eight for Fe and three for Zn) in rice grains on chromosomes 2, 3, 7, 10 and 12
Effect of production factors on maize yield and yield stability
No full textDifferent long-term experiments were carried on chernozem (Debrecen) and loamy (Hajdúböszörmény) soils. They included the most important agrotechnical, biological (hybrid) and agroecological (crop year, soil) factors in maize production. This paper evaluated the results of polyfactorial long-term experiments. For the maize the most favourable crop rotation was winter wheat (in a tri-culture) with an N 60–120, P2O5 60–70, K2O and 90–110 kg ha−1, and a density of 75–90,000 plants ha−1. The different input levels of maize crop management systems can modify an adaptive capacity to ecological conditions and the resilience of agro-ecosystems. The optimalization of agrotechnical elements reduces the harmful climatic effects. The yields of maize varied between 2–11 t ha−1 in extensive and 10–15 t ha−1 in intensive crop management systems, respectively