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191.
Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is an exotic species native to the USA, damaging cotton and other plant families. The feeding potential of different development stages of Cryptolaemus montrouzieri Mulsant, a biological control agent against mealybugs, was investigated on different development stages of P. solenopsis. Fourth instar grubs and adults of C. montrouzieri were the most voracious feeders on different instars of mealybug. The number of 1st instar nymphs of mealybug consumed by 1st, 2nd, 3rd and 4th instar larvae and adult beetles of C. montrouzieri was 15.56, 41.01, 125.38, 162.69 and 1613.81, respectively. The respective numbers of 2nd and 3rd instar nymphs of mealybug consumed were 11.15 and 1.80, 26.35 and 6.36, 73.66 and 13.32, 76.04 and 21.16, 787.95 and 114.66. The corresponding figures for adult female mealybugs were 0.94, 3.23, 8.47, 12.71 and 73.40, respectively. The results indicate that C. montrouzieri has the potential to be exploited as a biocontrol agent in North India; inoculative releases of 4th instar larvae and adults may provide instant control of P. solenopsis. Field experiments should be conducted to determine the efficiency of the ladybird on this mealybug.  相似文献   
192.
This study characterised the airborne mycobiota of a rice plantation in Bauta (Havana, Cuba), with a view to improving crop quality. Culturable airborne fungi were sampled between March 2007 and February 2008 using a volumetric method (SAS Super 100) with potato dextrose agar as culture medium. The total fungal count was 51,425 cfu/m3. The 39 filamentous genera identified included several major rice pathogens (Bipolaris, Curvularia, Alternaria, Pyricularia, Cercospora and Fusarium) as well as potentially mycotoxigenic species of Fusarium, Penicillium and Aspergillus. Analysis of the influence of weather-related factors on spore counts revealed that total counts and Penicillium counts correlated positively with daily relative humidity, mean temperature and dew point.  相似文献   
193.
Three kinds of plant growth regulators, gibberellinA 4/7 (GA 4/7 ), 6-benzylaminopurine (BA), and chlormequat chloride (CCC), were evaluated for their ability to promote strobilus and cone production in a Chinese pine (Pinus tabuliformis Carr.) clonal seed orchard. Treatments (0, 250, 500, or 1000 mg L -1 ) were applied during three periods (June- July, July-August and August-September) in 2005. Of the three plant growth regulators, GA 4/7 was the best for promoting flower and cone production. Trees sprayed...  相似文献   
194.
In recent decades, tremendous research has focused on the production of nanoscale fibers using synthetic polymers, with the goal of fabricating nanofibrous scaffolds for wound healing. However, the hydrophobicity of such polymers typically hinders attachment and proliferation of the cells. In this study, we combined poly-d,l-lactide-co-glycolide (PLGA) and small intestine submucosa (SIS) to fabricate blended nanofibers for wound healing by electrospinning. PLGA and SIS were dissolved in 1,1,1,3,3,3-hexafluoro isopropanol to produce different weight ratios of PLGA/SIS-blended nanofibrous membranes (NFM). Physicochemical characterization of the electrospun NFM was performed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, water contact angle analysis, degradation test and tensile testing. The PLGA/SIS-blended NFM showed improved hydrophilicity and tensile strength. Better infiltration, attachment and proliferation of rat granulation fibroblasts of PLGA/SIS-blended NFMs compared to PLGA NFMs were identified by morphological differences determined by SEM and a water-soluble tetrazolium salt assay kit. Based on our results, the PLGA/SIS blended NFMs were found to be suitable for use as a potential material for wound dressing.  相似文献   
195.
The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust (Fraxinus mandschurica Rupr.) and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290°C during 8 min (the conditions were similar to those employed on an industrial scale). The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry (GC-MS). The analytical r...  相似文献   
196.
Echinochloa crus-galli (L.) P. Beauv. (barnyardgrass) is an annual weed that is native to Asia and found throughout the world. The broad ecological tolerance and competitive ability of E. crus-galli makes it the most important weed species in rice. Genetic studies of plants are becoming increasingly common because reliable information is necessary to better understand population dynamics, occurrence of herbicide resistance, and demographic data. Echinochloa crus-galli populations from 34 different locations in Turkey were compared with respect to morphological differences and genetic variation. For morphological variation, five seeds of each population were sown in pots and grown in a screenhouse using a randomized block design. Morphological parameters such as germination speed, flowering time, leaf area, plant height, spikelet length, above-ground biomass, root dry weight and number of seeds were measured. Distinct differences among populations with respect to hierarchical cluster analysis were observed. Genetic variations among populations were performed using random amplified polymorphic DNA (RAPD) markers. The seven RAPD primers amplified 55 bands whose molecular weight varied between 200 and 4000 bp. The percentage of polymorphic bands was 74.54%. Results showed high morphological and genetic variability among individual genotypes within geographic locations. Phenotypic and genetic variability among E. crus-galli populations would be influenced by agricultural practices, crop characteristics, geographic location and herbicide pressure. Differences between weed populations may affect response to chemical or biological control.  相似文献   
197.
The PTM3 (MADS-box) gene characterized from flower of Aspen was ectopically expressed in cotton and was found to result in desirable agronomic traits. Among several transgenic lines, the PTM3 cotton event-10 was found to flower significantly earlier than the control and yield better [Ramachandran et al. (2011)]. We report our findings on performance based on greenhouse evaluation and inheritance of PTM3 cotton event-10. The T1 progeny of event-10 were grown in pots under RBD design. The progeny were confirmed by kanamycin imbibition test, PCR, and GUS assay which showed the segregation of transgene at about 3:1 ratio. GUS assay was performed with pollen from all transgenic plants; plants that expressed gus in all pollen versus those that showed segregation for expression were found to be at a ratio of 1:2. Similar to observations made in the T0 generation of event-10, the agronomic evaluation of T1 progeny exhibited, on an average, earliness of 13 days in flowering, 13.5 days in crop maturity, and 22% of yield enhancement. The T2 progeny of homozygous lines were grown on field soil in the greenhouse under strip trial design to see the effect as observed from potted plants of T1 progeny. Inheritance of transgene cassette to T2 progeny was confirmed by the same tests used to analyze T1 progeny. As exhibited by T0 and T1 progenies, the T2 progeny also showed earliness of 8 days in flowering, 12 days in crop maturity, and 17% of yield enhancement. The data generated from the progeny over two generations confirms that the PTM3 cotton event-10 is superior in agronomic characters as compared to non-transgenic cotton and is of interest for breeding shorter duration varieties with improved yield.  相似文献   
198.
AGPT and HA tests were employed for rapid diagnosis of PPRV infection in sheep and goats in Sudan. Forty lymph nodes and spleen samples from suspected cases of PPR in both sheep and goats were examined by AGPT and HA tests for detection of PPRV antigen. Viral antigen was detected from (77.5%) of the samples tested by AGPT and (92.5%) tested by HA test. The results of both tests revealed that HA test was more sensitive than AGPT for detection of PPRV antigen (Kappa statistics 0.4366). Another advantage of the HA test over AGPT was that it can differentiate PPRV from RPV. Thus the HA test represents a quick, easy, simple, cheap and reliable confirmatory test for the diagnosis of PPR and differential diagnosis of PPRV and RPV. The HA test was carried out using chicken, goat and pig RBCs. Chicken RBCs were found to be the most sensitive for detection of PPRV antigen, followed by goat then pig RBCs. The HA time when using chicken RBCs was 20–25 minutes, using goat RBCs was 25–30 minutes and using pig RBCs was 40–45 minutes. The distribution of PPR infection in four different regions of Sudan was investigated.  相似文献   
199.
Improvement of both the tensile and impact strength of the same polymeric material has always been a great challenge for the plastic industry. The study focuses on the effect of incorporation of calcium carbonate nanoparticles (0.3 wt% to 15 wt%) into three polypropylene (PP) based matrices viz. PP homopolymer, propylene-ethylene (PP-PE) copolymer and the blend of PP:PP-PE (30:70) to improve their impact behavior without hampering the tensile strength much. A loss in both the tensile and impact properties was observed in PP based nanocomposite. However, PP-PE based nanocomposites showed a significant improvement in impact strength (47 %) at 10 wt% loading with a loss of tensile strength by 22 %. To minimize this loss a blend of PP:PP-PE (30:70) was explored as a matrix. At 10 wt% loading, this matrix showed an improvement of 30 % in impact strength whereas the tensile loss was minimized to 10 %. Further, silane coupling agent which promoted good interfacial adhesion was used for best compositions. The variation of crystalline morphology of the nanocomposites with various formulations was analyzed using differential scanning calorimetry and X-ray diffraction.  相似文献   
200.
A durable aroma finishing for PET fabric was carried out by adopting poly(vinyl acetate) (PVAc) nanoparticles containing lavender oil (LO) in core. Relatively small size of PVAc nanoparticles (ca. 244 nm of mean particle diameter) was expected to resist the frictional destruction of the particles, which is frequently observed in cases of microcapsules. PVAc nanoparticles containing LO in core were prepared by emulsification-diffusion method and their application as an aroma releasing agent for PET fabrics was assessed through the observation of releasing profiles of LO in ethanol for experimental acceleration. Melamine-formaldehyde (MF) microcapsules containing LO were also prepared and treated on fabrics for comparison. PVAc nanoparticles treated on PET fabric showed higher initial releasing amount, which was ascribed to the enhanced surface area. After 2 days of releasing, PET fabric treated with PVAc nanoparticles showed slower and more stable releasing profile and reached about 12 ppm of cumulative release after 16 days, which was under two thirds of that with MF microcapsules. PVAc nanoparticles can be used as an agent for durable aroma finishing of PET fabrics.  相似文献   
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