Advanced Materials Research Vols. 518-523

Abstract: To investigate the change of cucumber root disease incidence and bacterial community shift in monocultrue soil, we established 4 treatments of greenhouse-pot cucumber, each representing various monoculture times, and monitored the bacterial variation in rhizosphere/bulk soil and root disease index. Results showed that culturable bacteria numbers gradually decreased as monoculture continued, a significant (P<0.05) difference was observed in rhizosphere samples of the fourth cropping (FC) and the third cropping (TC) soil in contrast to that of non-continuous cropping (NC). The Eco-Physiological diversity index also declined with consecutive cucumber cropping. Analysis by denaturing gradient gel electrophoresis (DGGE) showed that a few dominant bacterial species, including Pseudomonas sp. (95% similarity), Bacteriovorax sp. (93% similarity) and 2 uncultured soil bacteria, declined in population, while Sphingomonas sp. (100% similarity) and one uncultured bacterium increased. For all samples analyzed using DGGE or culture dependent approach, the bacterial population shift was more sensitive in the rhizosphere than in bulk soils, less bacterial diversity and higher root disease incidences were both detected in continuous monocultured soils.

Abstract: The acetolactate synthase(ALS) activity, glutathione S-transferase(GST) activity and glutathione(GSH) content in maize was investigated in response to treatments with safener (S)-3-dichloroacetyl-2,2-dimethyl-4-ethyl-1,3-oxazolidine. When induced by the chiral compound, the GSH content in root and shoot of maize increased 91.10% and 71.66%, respectively, the recovery rate of ALS activity reached 77%, and the GST activity increased 103.77%. The activity of maize GST was also assayed towards chlorsulfuron in vitro; the results showed that the induction of GST activity against chlorsulfuron of 14.54% was obtained. The enhancement of GST activity was found to be concomitant with changes in kinetic constants, which was related directly to the enzyme affinity for the CDNB substrate.

Abstract: In this paper, we selected the largest lakes wetlands Wuliangsuhai which in the same latitude of earth as study object. The TM satellite imagery of 2001 and 2010 was the data source. By Sensor calibrating and geometric precision correcting of information preprocessing, I analysis of different bands, spectral values, normalized difference vegetation index NDVI and water index NDWI characteristics on the basis of the establishment of the decision tree, classify information, and extract Wuliangsuhai aquatic vegetation information. This research has got a good extraction aquatic vegetation results of lakes and wetlands; the classification accuracy was 91.92% and 88.31% respectively. The results showed that wetland submerged plants area of 2010 in Wuliangsuhai lakes shrank by 67.81 % compared to 2001, and the water surface area of lake increased by 60.67%. These reflect that the eutrophication get a degree of control in Wuliangsuhai lakes wetland.

Abstract: The objective of this study was to understand the effects of mild, moderate and severe drought stress on zoysiagrass(Zoysia japonica). Superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and malondialdehyde (MDA) content were investigated. Mild drought(60%-70% of field capacity), moderate drought(45%-55% of field capacity), and severe drought (25%-35% of field capacity) were remained for 16 days. A gradual increase was observed in SOD activity of Zoysiagrass from 1 to13 days of drought stress in all treatments. POD and CAT activity, and lipid peroxidation increased in all treatments, and maximum change was happened in severe drought group. Severe drought has more serious damage to Zoysia japonica than mild drought and moderate drough. This suggests that Zoysiagrass has excellent drought tolerance and its ability to survive in the drought environment is very strong.

Abstract: The study was conducted to investigate the effects of commercial composite enzymes (CE) on growth, carcass composition and specific enzyme activities of juvenile flounder Paralichthys lethostigma. Four diets were formulated: one diet contained no CE (the control), the three others provided graded levels of CE (0.5%, 1% and 1.5%). Each diet was fed to pentaplicate of flounder juveniles for 28 days in aquaria (50×40×30 cm, water volume 50 L). The growth parameters (final wet weight, specific growth rate: SGR, feed conversion rate: FCR and apparent digestibility: AD) were significantly affected (P0.05). The CE had significant effects (P<0.05) on the specific activities of neural protease, alkine protease and amylase, but not on acid protease, amimopeptidase and alkine phosphatase. The pattern of the specific activities of neural protease, alkine protease and amylase was similar to that of SGR with fish fed diets containing 1.5% of CE exhibited the significantly higher activities (P<0.05). The results demonstrated that the supplement of CE in diets could significantly improve growth performance and digestive enzyme activities of flounder juveniles.

Abstract: Nostoc flagelliforme cells obtained from liquid culture were cultivated in sand and desert soil to investigate the ecological effects of N. flagelliforme in desert area. The result showed that the N. flagelliforme cells exhibited adaptability to draught similar to the wild N. flagelliforme trichome. The growth rate of N. flagelliforme cells on the sand is much faster than that of the trichome. Determinations of the water permeability and water retention showed that the N. flagelliforme cells can improve the soil quality. The result of soil surface crusting indicated that N. flagelliforme cells can adhere to the surface of the sand particles growing and forming the biological crust.

Abstract: Plant extracts were efficient, safe bio-control stuff. In this paper we used two kinds of plant extracts, Eugenol and Baicalein, to against Colletotrichum gloeosporioides and Agaricodochium camellia by growth rate method. The results show that the inhibition effects of eugenol and baicalein were increasing as the rising concentration form 0 to 200ug/ml. The EC₅₀ of eugenol against Colletotrichum gloeosporioides and Agaricodochium camellia were 30.37ug/ml and 51.55ug/ml respectively, the EC₅₀ of baicalein against Colletotrichum gloeosporioides and Agaricodochium camellia were 61.26ug/ml and 49.83ug/ml respectively. The synergistic interaction values of the compounded agents with different volume ratio against Colletotrichum gloeosporioides and Agaricodochium camellia were between 0.5 and 1.5. When the volume ratio of eugenol and baicalein were 1:1 ,the prevention and treatment effects of compounded agent and carbendazim with were the same, up to 60%.

Abstract: Wheat is the most important foodstuff of the cereals in view of its yield and consumption quantity in the world. However, allergens in wheat become one of the most severe medical problems. Therefore, recent research progresses on allergens of wheat were reviewed in this paper. Some allergens in wheat, for example, wheat lipid transfer protein, ω-5 gliadin, and α-amylase inhibit, have been analysed clearly, whereas others, salt-soluble protein, hydrolysed wheat proteins, wheat-germ agglutinin, and polysaccharide, were an obscure explanation.

Abstract: To investigate the efficacy of the compound preparation of traditional Chinese drug which is named KZY-2) on system fungi reside in faecal specimen of pigeon, the 66 faecal specimen of pigeon were collected from columbary of local park and residents.Each specimen which weigh 2.0g was mixed with 10ml sterile saline and the supernatant which volume was 1ml was incubated with the same volume drug which concentration were 200mɡ/ml,100mɡ/ml and 50mɡ/ml respectively at 37°C.After 24h,48h and 72h, the isolated positive rates of Cryptococcus neoformans and Candida albicans were calculated. Candida albicans was identified by gram staining, budding development, chlamydospore formation, sugar fermented test,sugar assimilated test and Cryptococcus neoformans was identified by gram staining,sugar fermented test,sugar assimilated test,urease tests,caffeic acid test, Hiss capsule staining.Results showed that the isolated positive rates of Cryptococcus neoformans and Candida albicans were 27.3%（18/66） and 16.7%（11/66） without drug action, KZY-2 could reduce the isolated positive rates of Cryptococcus neoformans and Candida albicans(P<0.05 and P<0.05).The drug concentration and action time could significantly affect the isolated positive rate which was negative correlation between them, higher drug concentration and longer incubation time,more lower the positive rate, especially the isolated positive rates of Cryptococcus neoformans are reduced 77.7%（6.1/27.3）which incubated with 200mɡ/ml drug after 72h compared with the control group.These results indicate The KZY-2 have good germicidal efficacy on Cryptococcus neoformans and Candida albicans isolated from faecal specimen of pigeon.

Abstract: The antioxidant capacity of the human body is closely related to its ability of disease resistance and anti-aging. It is a current research focus to find effective anti-oxidants used in medicine, food, health care, beauty make-up from natural plants. In this paper, we studied the content of selenium in selenium polysaccharide and its antioxidant activity in vitro of Thlaspi caerulescens L. produced from Yutangba of Enshi selenium mining area. The double tracts atomic fluorescence spectrometry is used to detect the total selenium content in the sample and that of selenium polysaccharide in the active ingredient of the sample. The salicylic acid method and pyrogallol autoxidation method are used to detect the scavenging activity of selenium polysaccharide on hydroxyl radicals and superoxide anion. Experiments show that the total amount of selenium in Thlaspi caerulescens L. is 708ug.g-1, while the amount of selenium in selenium polysaccharide is 98.1ug.g-1, accounting 13.86% of the total selenium content. Meanwhile, selenium polysaccharide in samples is with significant antioxidant capacity, and it shows a certain dose-effect relationship. Selenium polysaccharide has stronger anti-oxidation ability than pure polysaccharide compared with non-selenium polysaccharide. Therefore, plants rich in selenium are better natural antioxidants. This study will provide the necessary experimental basis for the effective and rational development and utilization of Thlaspi caerulescens L. rich in selenium