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31.
Journal of Pest Science - Conflicting views regarding synthetic pesticides include the successful use as pest management tools for agriculture and forestry on one hand and the threats to components...  相似文献   
32.
A study was carried out to determine the influence of different types of sludges (municipal, industrial and residential) on field germination, growth and nodulation of L. leucocephala seedlings in the nursery. Before sowing of seeds, different combinations of sludges were incorporated with the nutrient deficient natural forest soils. Field germination, nodulation status and physical growth parameters of seedlings (shoot and root length, vigor index, collar diameter, leaf number, fresh and dry weight of shoot and root and total dry biomass increment) were recorded after three and six months of seed sowing. Field germination, nodulation status and growth parameters were varied significantly in the soil amended with sludges in comparison to control. The highest number of nodule was recorded from soil amended with residential sludge ( 1:1 ) and highest fresh and dry nodule weight was also found from the same combination in both three and six month old seedlings. In case of growth parameters, the highest growth was recorded from soil and residential sludge ( 1:1 ) combination compared to control. From the study, it can be recommended that soil amended with residential sludge ( 1:1 ) provide better field germination, growth and nodule formation of L. leucocephala in degraded soil.  相似文献   
33.
We report the effects of shifting cultivation on water quality in 16 creeks investigated once in 2007 and twice in 2008 in 16 apparently similar small neighboring watersheds,each of 3 to 5 ha,at four locations around Barkal sub-district under Rangamati District of Chittagong Hill Tracts in Bangladesh.Concentrations of SO 4 2and K +,and pH in creek water were lower,and NO 3-N and Na + concentrations were higher in shifting-cultivation land compared to land with either plantation or natural forest or a combination of these cover types.Shifting cultivation effects on some water quality parameters were not significant due to change in land cover of the watershed between two sampling periods either through introduction of planted tree species or naturally regenerated vegetation.Conductivity and concentrations of HCO 3,PO 4 3,Ca 2+ and Mg 2+ in creek water showed no definite trend between shifting cultivation and the other land cover types.At one area near the Forest Range Office of Barkal,creek water pH was 5.8 under land cover with a combination of shifting cultivation and plantation.At this area Na + concentration in shifting-cultivation land ranged from 32.33 to 33.00 mg L-1 and in vegetated area from 25.00 to 30.50 mg L-1 in 2007.At another area,Chaliatali Chara,SO 4 2concentration in a shifting-cultivation watershed ranged from 4.46 to 10.51 mg L-1,lower than in a vegetated watershed that ranged from 11.69 to 19.98 mg L-1 in 2007.SO 4 2concentration in this shifting-cultivation area ranged from 1.28 to 1.37 mg L-1 and in the vegetated area from 1.37 to 3.50 mg L-1 in 2008.  相似文献   
34.
播种前对雨豆树(Albizia saman (Jacq.) F. Muell.)的种子进行了5 种预先处理,研究种子预先处理对种子发芽和苗圃种苗发育的影响。实验是在孟加拉吉大港大学林业与环境研究所的苗圃进行。研究结果表明,在种子末端修剪(处理4)提高种子发芽率50%,在冷水中浸泡24 小时(处理1)提高种子发芽率42%,在开水中浸30 秒后再在冷水中浸泡24 小时(处理2),种子发芽完全被抑制。处理4 和处理1 的种子发芽率、种苗初期形态生长和生物量都明显高于对照组。因此,这2 种播种前的种子预处理方法,可用于提高雨豆树种子发芽率和促进早期壮苗生长。图2 表3 参30。  相似文献   
35.
The effects of high temperature stress and supplemental irrigation on seed yield and water use efficiency (WUE) of canola (Brassica napus L.) were studied in a field experiment conducted for 2 years. The experiment was a randomized complete block design arranged in split plot, conducted at Agricultural Research Station of Gonbad, Iran. It was arranged in two conditions, i.e. supplemental irrigation and rainfed. Two cultivars of canola (Hyola401 and RGS003) as subplots were grown at five sowing dates as main plots. The sowing dates were 9 November, 6 December, 5 January, 4 February and 6 March in 2005-2006 and 6 November, 6 December, 5 January, 4 February and 6 March in 2006-2007, to have a wide range of environmental conditions around flowering and seed filling periods, and to coincide reproductive stages of the crop with high temperature stress. Seed yield was improved due to field management practices, such as supplemental irrigation and optimum sowing date. Supplemental irrigation was an efficient practice to mitigate water stress, and to increase aboveground dry matter and seed yield. There was a strongly negative relationship between seed yield and air temperature during reproductive stages. Delay in sowing led to more rapid developmental of canola, decreased aboveground dry matter, leaf area index (LAI), harvest index (HI), WUE, and seed yield. Achieving a high aboveground dry matter was an essential prerequisite for high reproductive growth and a high seed yield. Greater seed yield and WUE at first sowing date were associated with greater LAI and aboveground dry matter, and lower temperatures during reproductive stages. The results support the view that WUE can be used as an indirect selection criterion for seed yield in genotypic selection.  相似文献   
36.
Wet detention ponds are a preferable alternative in treating stormwater runoff. Literature suggests that a detention pond’s efficiency in removing principal pollutants of concern, TSS and metals, is highly variable and is affected by a complex array of factors including its geographic location. The objective of this paper was to investigate the TSS and metal removal efficiency of a highway stormwater detention pond in Spokane, Washington along with its flow regime. Pond influent and effluent data for TSS and metal were collected for approximately two years. TSS removal by the pond was found to be 68.1–99.4% with an average of 83.9%. Average metal removal efficiency was 54.7–64.6% which is 72.5–86.9% of the TSS removal. The pond’s flow regime was found to vary with its changing surface topography, a result of sedimentation of suspended solids.  相似文献   
37.
Low erucic acid (LEA) rapeseed, which has accumulated mutant fatty acid elongase genes at the BnFAE1.1 and BnFAE1.2 loci of the A- and C-genome, respectively, is an important oilseed crop. Short growing turnip rape (B. rapa) is also important as a catch crop in the continuous cropping of rice in Asia but there is no LEA B. rapa cultivar for cultivation in South Asia. In order to develop LEA turnip rape cultivars, high erucic acid turnip rape cultivars were interspecifically crossed as recurrent parents to a canola quality rapeseed. In the meantime, we monitored incorporation of the mutant bnfae1.1 (e1) gene into A-genome of turnip rape, using a dCAPS primer pair, which can amplify PCR fragment only for the mutant e1 gene from A-genome. The early backcross progenies showed poor seed set, but which was improved in advanced progenies. Finally, homozygous e1e1 genotypes were established in the selfed progenies of BC2–BC3, and their LEA content was confirmed by gas-chromatography analysis. Our results and promising lines will contribute to LEA-trait selection in turnip rape and rapeseed breeding.  相似文献   
38.
Journal of Crop Science and Biotechnology - Salinity is one of the most brutal abiotic stressors, commencing a great stumbling block in the way of attaining food security in Bangladesh. Cultivation...  相似文献   
39.
Vitamin A deficiency in humans is a widespread health problem. Quality protein maize (QPM) is a popular food rich in lysine and tryptophan, but poor in provitamin A (proA). Here, we report the improvement of an elite QPM inbred, HKI1128Q for proA using marker‐assisted introgression of crtRB1‐favourable allele. HKI1128 was one of the parental lines of three popular hybrids in India and was converted to QPM in our earlier programme. Severe segregation distortion for crtRB1 was observed in BC1F1, BC2F1 and BC2F2. Background selection by 100 SSRs revealed mean recovery of 91.07% recurrent parent genome varying from 88.78% to 93.88%. Across years, introgressed progenies possessed higher mean β‐carotene (BC: 9.22 µg/g), β‐cryptoxanthin (BCX: 3.05 µg/g) and provitamin A (proA: 10.75 µg/g) compared to HKI1128Q (BC: 2.26 µg/g, BCX: 2.26 µg/g and proA: 3.38 µg/g). High concentration of essential amino acids, viz. lysine (mean: 0.303%) and tryptophan (0.080%) in endosperm, was also retained. Multi‐year evaluation showed that introgressed progenies possessed similar grain yield (1,759–1,879 kg/ha) with HKI1128Q (1,778 kg/ha). Introgressed progenies with higher lysine, tryptophan and proA hold immense potential as donors and parents in developing biofortified hybrids.  相似文献   
40.
The effects of both coffee components and coffee extract on the electrical responses of GABA(A) receptors expressed in Xenopus oocytes were studied by injecting cRNAs of the alpha(1) and beta(1) subunits of the bovine receptors. The aqueous extract of coffee dose-dependently inhibited the GABA-elicited responses, whereas the lipophilic extract of coffee by diethyl ether slightly potentiated it at low doses (0.1-0.4 microL/mL) but showed inhibition at high doses (0.5-0.8 microL/mL). Theophylline inhibited the response in a noncompetitive mechanism (K(i) = 0.55 mM), whereas theobromine and trigonelline hydrochloride inhibited it in a competitive manner, K(i) = 3.8 and 13 mM, respectively. Benzothiazole, catechol, 2,4-dimethylstyrene, guaiacol, 1-octen-3-ol, sotolone, and 2,3,5-trimethylphenol potentiated the responses significantly. Potentiation elicited by guaiacol and sotolone was independent of GABA concentrations, whereas that by 1-octen-3-ol was dependent. When 1-octen-3-ol (100 mg/kg) was orally administered to mice prior to intraperitoneal administration of pentobarbital, the sleeping time of mice induced by pentobarbital increased significantly.  相似文献   
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