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31.
Sherif A. Hassan 《Journal of pest science》1969,42(7):112
Ohne Zusammenfassung
Observations On The Effect Of Insecticides On Coleopterous Predators OfErioischia Brassicae (Diptera: Anthonmyiidae). Beobachtungen über die Wirkung von Insektiziden auf Prädatoren(Coleoptera) vonErioschia brassicae (Diptera: Anthomyiidae)相似文献
32.
The pharmacokinetics of kitasamycin after intravenous and oral administration in a dose of 300 mg/kg b.wt. was studied in 18 healthy and 18 Salmonella gallinarum naturally infected chickens. The tissue residue of the studied antibiotic was estimated in 36 normal chickens when it was given orally for 7 successive days. Therapeutic level of kitasamycin was achieved after 15 minutes and persisted for 20-22 hours after its oral administration. Higher serum kitasamycin concentrations were recorded in Salmonella gallinarum infected chickens. The elimination half-life of kitasamycin calculated after single intravenous injection was 9.03 hours in diseased chickens corresponding to 3.74 hours in healthy birds. The body clearance was significantly reduced in diseased chickens (23.86 ml/kg/min) when compared to that in normal ones (62.03 ml/kg/min). Kitasamycin treated broilers should not be slaughtered before 3 days from the last dose as it was detected only in bile and caecum at that time but not in edible tissues. 相似文献
33.
M. Farooq T. Aziz M. Hussain H. Rehman K. Jabran & M. B. Khan 《Journal of Agronomy and Crop Science》2008,194(2):152-160
Plant growth and development is hampered by various environmental stresses including chilling. We investigated the possibility of improving chilling tolerance in hybrid maize by glycinebetaine (GB) seed treatments. Maize hybrid (Hycorn 8288) seeds were soaked in 50, 100 and 150 mg l?1 (p.p.m.) aerated solution of GB for 24 h and were dried back. Treated and untreated seeds were sown at 27 °C (optimal temperature) and at 15 °C (chilling stress) under controlled conditions. Germination and seedling growth was significantly hindered under chilling stress. Moreover, chilling stress significantly reduced the starch metabolism and relative water contents (RWC), and increased the membrane electrolyte leakage. However, activities of antioxidants (catalase, superoxide dismutase and ascorbate peroxidase) were increased under stress conditions. Seed treatments with GB improved the germination rate, root and shoot length, seedling fresh and dry weights, leaf and root scores, RWC, soluble sugars, α‐amylase activity and antioxidants significantly compared with untreated seeds under optimal and stress conditions. Induction of chilling tolerance was attributed to maintenance of high tissue water contents, reduced membrane electrolyte leakage, and higher antioxidant activities and carbohydrate metabolism. Seed treatment with 100 mg l?1 GB was the best treatment for improving the performance of hybrid maize under normal and stress conditions compared with control and other levels used. 相似文献
34.
Liquefaction of bagasse and cotton stalks was conducted by using polyhydric alcohols (polyethylene glycol PEG#400 and glycerin) in the presence of sulfuric acid (SA) as a catalyst. The effects of different liquefaction conditions, such as ratio raw material/liquefying solvent, effect of PEG#400/glycerin, acid concentration, liquefaction temperature and time on the liquefaction yield have been investigated. The hydroxyl and acid numbers for some liquefied samples were also determined. The results showed that the minimum residue content was obtained at 1/5 raw material to liquefying solvent. PEG#400 alone is not favoured as liquefying solvent as it gives ∼19% residual content for bagasse and ∼22% for cotton stalks at the optimum studied reaction conditions. Replacing 10% of PEG#400 with glycerin as well as increasing the SA concentration, liquefaction temperature or time, decreased the amount of residue for both bagasse and cotton stalks to less than 10%. The hydroxyl number of the produced polyols slowly decreased from 253 to 223 mg KOH/g on extending the reaction time till 120 min and the residual polyols prevented re-condensation of the liquefied components. It seems that this system can be applied on various types of lignocellulosic agricultural residues. 相似文献
35.
36.
Cultivated peanut, the second most economically important legume crop throughout the United States and the third most important
oilseed in the world, is consistently threatened by various diseases and pests. Sclerotinia minor Jagger (S. minor), the causal agent of Sclerotinia blight, is a major threat to peanut production in the Southwestern U.S., Virginia, and
North Carolina and can reduce yield by up to 50% in severely infested fields. Although host plant resistance would provide
the most effective solution to managing Sclerotinia blight, limited sources of resistance to the disease are available for
use in breeding programs. Peanut germplasm collections are available for exploration and identification of new sources of
resistance, but traditionally the process is lengthy, requiring years of field testing before those potential sources can
be identified. Molecular markers associated with phenotypic traits can speed up the screening of germplasm accessions, but
until recently none were available for Sclerotinia blight resistance in peanut. This study objective of this study was to
characterize the US peanut mini-core collection with regards to a recently discovered molecular marker associated with Sclerotinia
blight resistance. Ninety-six accessions from the collection were available and genotyped using the SSR marker and 39 total
accessions from spanish, valencia, runner market types were identified as new potential sources of resistance and targeted
for further evaluation in field tests for Sclerotinia blight resistance. 相似文献
37.
Hassan Amiri Oghan Mohammad Moghaddam Vahed Reza Ataei Majid Gholamhosseini 《Euphytica》2018,214(6):91
Major advancement in canola breeding depends on heterotic hybrids that require high general combining ability (GCA) and specific combining ability (SCA) inbred lines. In order to estimate heritability, gene action type, GCA, SCA and heterosis and to identify superior hybrids with wider adaptation to cold, one hundred canola hybrids were produced by crossing 10 lines and 10 testers in a Line?×?Tester mating design. The F1 and F2 generations were sown in α-lattice design in 2012 and 2013 growing seasons under optimum (early October) and late sowing (early November) conditions to be evaluated for days to flowering, days to physiological maturity, number of pods per plant, number of seeds per pod, thousand seed weight, seed yield and leaf electrical conductivity. The combined analysis indicated sufficient genetic diversity in the population and significant difference between two sowing date. The Line?×?Tester analysis presented significant GCA and SCA effects for all studied traits across optimum and late sowing conditions. The main gene action type was found to be non-additive, especially incomplete dominance and over-dominance in both conditions. Narrow-sense heritability ranged from low to moderate whereas broad-sense heritability was recorded more than 60% for all of the studied traits in both generations and conditions. The average heterosis in F2 population for all studied traits was lower than that in F1 representing this fact that heterosis is generally related to the heterozygosity at the population level and poorly correlated with heterozygosity at the individual level. 相似文献
38.
Maryam Aflaki Jalali Hassan Bahrami Sirmandi Abdullah Hatamzadeh 《Journal of Crop Science and Biotechnology》2017,20(1):29-35
Low efficiency of somatic embryo maturation, germination, and conversion to plantlets is a major problem in many species including J. regia L. Germination efficiency of somatic embryos is very low in walnut. In this study, effects of two carbohydrate sources, sucrose and maltose (each at 3% and 6%), and two kinds of PEG (4000 and 6000) (each at four levels of 1.5%, 3%, 5% and 7.5%) on maturation and germination of walnut embryos were tested. The number of somatic embryos increased conspicuously on medium containing PEG. Furthermore, higher levels of PEG-4000 (7.5%) could remarkably enhance the morphogenesis of somatic embryos and the number of embryos produced. PEG-4000 stimulated somatic embryo maturation of walnut. This stimulatory effect was dependent on the carbohydrate source used. Sucrose in combination with PEG-4000 produced 50% of cotyledonary and normal somatic embryos. Different concentrations of PEG were effective on the number of embryos with a shoot meristem. PEG-4000 7.5% and sucrose 3.0% produced the highest rate (50.0%) of normal shooting embryos. However, PEG (4000, 6000) and maltose caused an unfavorable effect and increased the frequency of abnormal shaped somatic embryos. 相似文献
39.
Genetic progress in wheat yield and associated traits in China since 1945 and future prospects 总被引:2,自引:0,他引:2
Genetic progress has brought about a dramatic increase in yield potential per se for almost all production areas around the world. The present study examines the relationship of wheat yield with year of release, yield components, harvest index (HI), biomass production, and plant height. We used aggregative data from 1945 to 2010 to calculate genetic gain in wheat yield across different zones in China. A deeper understanding of these issues facilitates the identification of specific yield-limiting factors that can be used for future breeding strategies. Absolute yield gain for the different zones was found to range from 20 to 103 kg ha?1 year?1, whereas relative yield gain ranged from 0.33 to 1.42 % per year. When data from all the Chinese wheat production zones was pooled, yield gain at the national level had an absolute value of 66 kg ha?1 year?1 and a relative value of 1 % per year. Grain weight and spike weight, rather than the other yield components, are significantly correlated with year of release for most zones, suggesting that these two were the most promising traits for breeders in the past. These two traits are also responsible for the significant genetic progress in wheat yield in China since 1949. HI and biomass production also showed strong correlation with year of release and grain yield. In China, HI and grain weight have experienced such a substantial increase that both have almost reached their theoretical maxima in the period 1945–2010. Further improvement in the yield potential of wheat will have to involve increase in biomass production and grain number. This paper also reviews cropping systems and technologies as well as improvement in physiological trait from 1945 onwards during the period of genetic gain. 相似文献
40.
Improved planting methods and foliar application of glycinebetaine (GB) and salicylic acid (SA) can improve the water productivity in field crops under limited water supply conditions. A 2‐year field study was conducted to evaluate the possible role of different planting methods and foliar applications of GB and SA in improving the yield, quality and water productivity of hybrid sunflower (Helianthus annuus L.). The crop was planted by flat sowing (75 cm spaced rows) and ridge sowing (75 cm spaced ridges), with GB and SA applied exogenously at 100 and 0.724 mm , respectively, at both budding and flowering stages, while control plots received distilled water. Ridge sowing, rather than flat sowing, improved the biological yield, oil yield, leaf area index (LAI), crop growth rate (CGR), plant height, water‐use efficiency and final achene yield during both the years. Foliar applications of GB and SA at both the stages improved the achene yield, although foliar application of GB at flowering was the most effective. Neither the planting methods nor the foliar application of GB and SA altered the achene oil contents during both the years. Foliar application of GB and SA increased the free proline content of the leaf and GB contents at flowering but reduced the achene protein contents, whereas planting method had no effect on these attributes across the years. Of the foliar applied chemicals, GB was more effective in improving sunflower growth and yield and water productivity than SA. To conclude, ridge sowing coupled with foliar application of GB at flowering stage could be beneficial for achieving maximum yields of hybrid sunflower under relatively water limited conditions in the field. 相似文献