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1.
Paddy and Water Environment - Japan has many concrete irrigation channels with total length of about 400,000 km. Most of these channels are now too old for continued use. It would be too...  相似文献   

2.
The brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), is a long-distance migratory insect pest in temperate eastern Asia and a typical recurrent pest induced by pesticides. We investigated the effect of sublethal concentrations of insecticides on the flight capacity on this species. An automated flight-mill system was used to assess the flight capacity of adults reared on untreated and insecticide-treated plants. In most instances, the flight duration of adult females exposed to high concentrations of imidacloprid, triazophos or deltamethrin was significantly greater than that of untreated controls. Compared to the controls, the flight duration of females increased by 140% (from 103 to 245.9 min), 119% (from 103 to 226 min) and 78% (from 103 to 183.3 min) with 10 ppm imidacloprid, 40 ppm triazophos and 3 ppm deltamethrin, respectively, yet no significant difference in the flight duration of males was found between the insecticide treatments and the controls. The high concentrations of the three insecticides significantly enhanced the flight speed and the flight distance of both males and females, with the exception of the flight speed of adult males treated with deltamethrin. For example, the flight speed of adult females and males treated with 10 ppm imidacloprid, 40 ppm triazophos and 6 ppm deltamethrin increased by 75% (from 0.39 to 0.68 km/h), 154% (from 0.39 to 0.98 km/h) and 124% (from 0.39 to 0.87 km/h) for females and by 141% (from 0.32 to 0.77 km/h), 73% (from 0.32 to 0.55 km/h) and 48% (from 0.32 to 0.47 km/h) for males, respectively, compared to the controls. In addition, the percentages of individuals treated with imidacloprid and triazophos flying for over 60 min doubled compared to the control. These findings are relevant for understanding the migration and outbreak patterns of N. lugens.  相似文献   

3.
Paddy and Water Environment - Hyperthermophilic pretreatment (80 °C, 24 h) is a technology that promotes methane yield in the anaerobic digestion of sewage sludge. However,...  相似文献   

4.
Paddy and Water Environment - This research focused on two large-scale paddy irrigation schemes of Doho (1000 ha) and Lwoba (700 ha) in Uganda for a comparative analysis of major...  相似文献   

5.
The Indian gypsy moth (Lymantria obfuscata) is a pest of national significance, which attacks a wide range of forest and fruit crops in India. The outbreaks of this pest over the past few years spurred interest towards sustainable biointensive approaches for quality fruit production of apple and walnut for agricultural export in Jammu & Kashmir (J & K). The exploratory survey's were conducted for the isolation of native strains of L. obfuscata multiple nucleopolyhedrovirus (LyobMNPV) and field evaluation was conducted to determine the most promising strain as a potential biological control agent of this pest. The virus was recovered from different locations of J&K with its natural incidence varying from 0.77 to 7.43 percent. This is the first report from the Indian sub-continent and worldwide of the occurrence of NPVs in natural larval populations of L. obfuscata. The in vivo mass production was optimised by inoculating per os late 3rd instar L. obfuscata larvae with an inoculum dose of 1.44 × 105 OBs/larva and followed by a 10 day incubation period. To prevent the disintegration of larval cuticle and microbial contamination, moribund larvae were harvested with an average yield of 1.42 × 108 OBs/larva. The field application of LyobMNPV against the host populations on apple and willow with the pre-standardised dosage of 2.5 × 1012 OBs/ha reduced the larval population density by 25–63%. In the year following application, the larval population density in the treated blocks was 19–28% lower as compared to controls on both apple and willow. This suggests that the virus has considerable potential as a biocontrol agent and the timely application with LyobMNPV on non-fruit trees such as willow which are the preferred hosts for egg laying may help to initiate viral epizootics to keep population outbreaks under check.  相似文献   

6.
Paddy and Water Environment - This paper proposes a new approach to predicting dry season periods by using annual cumulative rainfall for the past 35 years to determine dry season...  相似文献   

7.
Paddy and Water Environment - In this study, two types of superabsorbent polymers, Luquasorb (Luqua) and Stockosorb (Stock), at 180 kg ha−1 were applied by scattering and...  相似文献   

8.
Paddy and Water Environment - Radiocesium released from Fukushima Daiichi nuclear power plant in March 2011 was accumulated in paddy fields within 5 cm of the surface soil layer. In order...  相似文献   

9.
Plant Foods for Human Nutrition - The flash vacuum-expansion process (FVE) consists of two stages. In the first, the raw material is heated by a steam flow in a chamber at 101.325 kPa; in...  相似文献   

10.
Plant Foods for Human Nutrition - Corn kernels were soaked with different selenium (Se) solutions (0, 12 or 24 mg Na2SeO3/L), sprouted for different times and then lime-cooked for the...  相似文献   

11.
Spotted stemborer, Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae), is the most important pest of sorghum in Asia and south and eastern Africa. Host plant resistance is an important control tactic for controlling this pest. Two breeding lines 27B × PB 15881-3 and 463B × PB 15881-3 with their parents, resistant and susceptible genotypes were evaluated in the field, glasshouse and laboratory for different resistance parameters. Breeding lines and genotypes varied significantly in foliar damage ratings, percentage of stem length tunneled, percentage of plants with deadhearts, larval survival, larval and pupal weights, larval and pupal duration, and percentage pupation and adult emergence in diets amended with leaf powder of different sorghum genotypes. The breeding lines 27B × PB 15881-3 and 463B × PB 15881-3 showed antixenosis and antibiosis to C. partellus in terms of reduced eggs per plant, larval survival and development. The levels of antixenosis and antibiosis of both breeding lines were similar to their resistant parents. Results indicate that transmission of characteristics responsible for resistance to the progeny from the resistant parent occurred.  相似文献   

12.
Anthracnose, caused by fungal pathogen Colletotrichum lindemuthianum (Sacc. & Magnus) Briosi Cav. is one of the main production constraints of the dry bean (Phaseolus vulgaris L.) industry in Ontario. A field study was carried out in 2007 and 2008 to investigate the effect of two seed treatments (DCT (diazinon + captan + thiophanate-methyl) and MFA (metalaxyl-M + fludioxonil + azoxystrobin)) and two foliar fungicides (pyraclostrobin and azoxystrobin) applied with and without a surfactant under low and high disease pressure conditions at Exeter ON. Eighteen treatment combinations were tested in a randomized complete block design with four replicates. The treatment effects were examined by measuring disease development on leaf and pod tissue, pod destruction index, pick (discolored and misshaped seed), yield and return on investment (ROI). The seed treatment MFA performed similarly to DCT, and should be considered a suitable replacement to DCT for dry bean growers. However, utilizing a strobilurin fungicide in both seed and foliar treatments raises concern, as this practice increases the risk of disease resistance. The addition of a surfactant to azoxystrobin increased seed yield and ROI under high disease pressure, but had no effect when added to pyraclostrobin. Pyraclostrobin outperformed azoxystrobin for some disease indices as well as for yield under high disease pressure and for ROI under low and high disease pressure conditions.  相似文献   

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Five experiments with in vitro-grown plantlets of potato cvs ‘Superior,’ ‘Early Valley,’ ‘Golden Valley,’ and ‘Winter Valley’ were carried out to investigate in a stepwise approach the potential for enhancing microtuber production of (1) adding supplementary nutrients (SN) including KNO3, NH4H2PO4, Ca(NO3)2.4H2O, and MgSO4 in full- or half-strength Murashige and Skoog (MS) medium, (2) adding a pretested combination of plant growth regulators (PGRs), i.e., 10 mg l−1 6-benzyl aminopurine plus 200 mg l−1 succinic acid 2,2-dimethylhydrazide, (3) varying the timing of the supplemental applications, and (4) varying the replenishment of the medium. Plantlets of ‘Superior’ for microtuberization were grown from two-node explants for 75 days under environmental conditions consisting of 22 ± 2 °C and a 16-h photoperiod on a solid basal medium consisting of half-strength MS (1/2 MS) medium containing 6 % sucrose and a moderate concentration of supplementary nutrients, SN-2 (KNO3, 1.22 g l−1; NH4H2PO4, 1.41 g l−1; Ca(NO3)24H2O, 0.23 g l−1; and MgSO4, 0.74 g l−1). Thereafter, plantlets were grown for 60 days under dark conditions. Liquid media containing different combinations of MS, SN, and PGR levels plus 8 % sucrose were added as a supplement and were evaluated for their ability to increase tuberization compared to the control composition of the supplement (MS with 8 % sucrose). In the first experiment, addition of 1/2 MS liquid medium containing 8 % sucrose and SN-2 before dark incubation induced the highest total number of microtubers (on average 1.4 per plantlet), a significantly higher weight and size than the control, and the highest percentage (50 %) of large-sized (>500 mg) microtubers. In the second experiment, addition of 1/2 MS liquid medium containing 8 % sucrose, SN-2, and PGRs produced the highest number (on average 1.5 per plantlet) and total yield (on average 971 mg per plantlet) of microtubers, and significantly the highest percentage (66 %) of large-sized (>500 mg) microtubers. The size of the microtubers was higher than for the treatment without growth regulators. The optimum time for addition of supplemental medium containing 8 % sucrose, SN-2, and PGRs was shown in experiment 3 to be latest 1 week before dark incubation. This timing resulted in both the highest microtuber number (on average 1.6 per plantlet) and yield (on average 1208 mg per plantlet), and the highest percentage (64 %) of large-sized microtubers. Finally, it was found that a second supplemental treatment consisting of 50 % replacement of the liquid medium (by volume) 2 weeks after transfer to dark conditions gave rise to the highest number (on average 1.9 per plantlet), yield (on average 1346 mg per plant), and also significantly the highest percentage (25 %) of large-sized microtubers (>1000 mg) as compared to replacement of a greater or smaller proportion of the medium. Four potato cultivars, ‘Superior,’ ‘Early Valley,’ ‘Golden Valley,’ and ‘Winter Valley’ produced acceptable numbers and yield of microtubers of relatively large-sized tubers using a process that included supplemental liquid medium with 1/2 MS, 8 % sucrose, moderate concentration (SN-2) of SNs and PGRs, followed by a 50 % replacement of the same medium.  相似文献   

17.
Plant Foods for Human Nutrition - This study aims at understanding the relation among sprouting time (from 12 up to 72 h), changes in protein and starch components, and flour functionality...  相似文献   

18.
A light commercial road vehicle fitted with a heated fuel line and tank was run on cold pressed and filtered camelina sativa seed oil and unheated mineral diesel fuel. It was found that the seed oil produced a maximum power at the road wheels of 43.25 kW and returned 12.57 km/l compared to 38.50 kW and 14.03 km/l for the mineral fuel. At an engine speed >2000 rpm and high loading, both smoke opacity and CO emitted from the exhaust was found to be approximately 50% lower with the seed oil than with the mineral fuel, however, NO was higher for the seed oil by almost 6% at engine speeds >3500 rpm, but similar <3500 rpm. The CO2 and O2 emissions were similar and NO2 emitted was negligible for both fuels. The effect of heating at 170 °C on the camelina sativa seed oil was investigated and a significant increase in viscosity was observed which coincided with a reduction in the iodine value of the oil.  相似文献   

19.
Paddy and Water Environment - In South Florida, approximately 11,000&nbsp;ha of rice is grown every summer on highly organic histosols. With no added fertilizer inputs of phosphorus (P) or...  相似文献   

20.
The essential trace mineral, selenium (Se), is of fundamental importance to human health. Tartary buckwheat is a pseudocereal variety rich in functional flavonoids. To investigate the characters of Se-enriched Tartary buckwheat in Shaanxi province, we studied effect of different processing methods on its nutrients and selenium distribution in Se-enriched buckwheat groat (Se-BG), milled flour (Se-BMF), extruded flake (Se-BEF) and roasted groat (Se-BRG). The highest total selenium content in Se-BG was 118.04 μg/kg. Se-BMF (110.55 μg/kg) and Se-BEF (98.55 μg/kg) showed less selenium loss while the most selenium loss was recorded in Se-BRG (66.63 μg/kg). Selenium and selenomethionine (SeMet) were mainly present in glutelin, followed by albumin. SeMet content followed the trends of Se-BG (76.21 μg/kg groat) > Se-BMF (75.24 μg/kg groat) > Se-BEF (64.76 μg/kg groat) > Se-BRG (21.21 μg/kg groat).This shows that processing also has a great influence on the distribution of selenium forms.  相似文献   

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