Advanced Materials Research Vols. 610-613

Abstract: Tomato late blight disease that infected by Phytophthora infestans (Mont.) de Bary has already become one of the main obstacles that influence the tomato production. To resolve tomato late blight disease, cultivating the disease-resistant breed is importance. Based on the previous study, different introduced varieties were used as materials in this test for the identification and varieties selection of tomato resistant to late blight, by measuring the DIS of inoculated seedlings and detached leaves. It indicated that Jingle 502 and O-33-1 are possible to become resistant varieties to late blight or the parents for cultivating new disease resistant varieties.

Abstract: Conidia of Beauveria bassiana Bb-202, which have the potential for the control of the coleopteran pests, were produced on rice by solid-state fermentation (SSF) using tray bioreactor. As the solid substrate thickness increased, the production of conidia decreased. By cutting substrate into many small uniform pieces, metabolic heat and gas transfer in center of substrate could be improved. We concluded that the highest yield of 3.94×1012 conidia kg-1 rice was obtained as the substrate of 2cm thickness was cut into many small pieces (6cm×4cm×2cm). And the average yield of conidia increases by 45%. It indicated that cut solid substrate into many pieces would increasing the surface area of substrate. So the conidia yields were significantly increased.

Abstract: Field survey and laboratory experiment were conducted to study the characteristics of soil seed banks (SSBs) in typical Saline-alkali wetlands in Tianjin Binhai New Area. The composition, diversity and temporal and spatial distribution of SSBs in three sampling plots were analyzed. The results show that there are 26 species in the SSBs, with species density 6809~30644 grains/m2 and ecological dominance at 0.51~0.81. The diversity index show a relatively low value - the highest Shannon-Wener value is 1.78. The similarity coefficients between SSB and aboveground vegetation are low as well, the lowest value is 0.21. Vertical distribution demonstrates significantly obvious condition with 0-5cm layer having the most species.

Abstract: This review emphasizes on discussing the diversity and ecoadaptability of the environment on botanical features, nitrogen fixation and biochemical components of Leguminosae, especially legumes in the Papilionoideae. Though these features such as hard seeds, nitrogen fixation and anti-nutritional compounds (ANCs) are disadvantageous in the aspects of agronomy, photosytherate accumulation and the processing and consuming of seed respectively, but these may have very important functions in germplasm existence, multiplying and survive to the different circumstances, that had kept to the abundant and distribute ecosystem adaptability of these species extensively. It is important and realistic to discover and utilize of tolerance and resistance to the stress circumstances of Leguminosae, study and inquiry into its adaptability mechanism, for keeping biodiversity and tolerance breeding of these plants.

Abstract: Caragana microphylla is a pioneer leguminous shrub species, and plays an important role in sand fixing and desertification control in the Horqin Sandy Land of Northern China. In this study, seedlings were buried by sand to depths of 0 (control), 1/3, 2/3, 1 and 4/3 of their mean height, and the effects of sand burial depth on seedling growth of Caragana microphylla were tested. Results show that with increasing burial depth, biomass allocation to leaves decrease, while stem biomass allocation increase, and both shoot and root growth of C. microphylla are stimulated and seedling biomass is the highest when burial depth is 2/3 of seedling height. Therefore, moderate burial could facilitate seedlings growth of C. microphylla

Abstract: Fast-growing Poplar cooked by Soda-AQ process was studied, by determining the lignin contents including Klason lignin and acid soluble lignin, the yield of pulping, the rate of carbohydtare degradation and the rate of delignification.Results indicated that the delignificaton of Fast-growing Poplar in Soda-AQ pulping can be divided into three distinguishable stages. (a)The initial delignification stage before 140°C,the rate of delignification reaches to 30.87%;(b)The bulk delignification stage, the rate of delignification reaches to 86.97%，in the period from 140°C to 170°C and for 30 min;(c)The residual delignification stage,the rate of delignification exceeds 91.60%. The defibration point was reached when cooking temperature raised to 170°C and for 30 min with 57.50% pulping yield ,24.94 kappa nomber.

Abstract: The effects of pretreatment by xylanase on properties of salix psammophila KP were researched in this paper.The effects of different dosage of enzyme on fibre morphology and paper properties were studied. The results showed that pulp properties can be improved by pretreatment with xylanase.The fibre average length increases after pretreatment, fines content decreased and brightness and physcial properties improved. Brightness and physcial properties improved and scattering coefficient,absorption coefficient and opacity decreased with dosage of enzyme increasing. But brightness and physcial properties decrease and scattering coefficient,absorption coefficient and opacity increases slightly when the dosage of enzyme beyond 10IUg-1.X-ray diffractometer analysis indicated that the degree of crystallinity of fibre increased after xylanase pretreatment.

Abstract: Cylindrocarpon root rot, caused by Cylindrocarpon destructans, is a severe disease on ginseng (Panax ginseng C.A. Meyer) in northeast China. Methyl jasmonate (MeJA) has been studied for its ability to induce plant defenses against pathogens. The effects of MeJA on the colony diameter of C. destructans and seedling growth were examined in vitro. Two-year-old ginseng roots were drenched with MeJA (200 mg/L) and then inoculated with conidia suspension of C. destructans (1×106 conidia/ml). Disease severity was assessed on inoculated roots, and the activation of defense responses was also measured. Results showed that MeJA had no effect on the growth of C. destructans and seedlings at low concentrations. The incidence rate and disease severity on MeJA-treated ginseng roots was significantly reduced compared with untreated roots. The proline content was increased but the malondialdehyde (MDA) content decreased in MeJA- treated roots. The activities of phenylalanine amino-lyase (PAL), catalase (CAT), peroxidase (POD) and polyphenoloxidase (PPO) were significantly enhanced in treated roots. It was concluded that low concentrations of MeJA had no effect on C. destructans, but it stimulated the activities of defense enzymes in treated ginseng roots and alleviated the damage of roots from C. destructans. Therefore, the control of Cylindrocarpon root rot by MeJA may involve the activation of the disease-related defense system.

Abstract: The quality attributes and storage life of ‘Irwin’ mango fruit can be effectively maintained with 1-methylcyclopropene (1-MCP) application and/or chitosan coating. Mango was treated with 5 µl l^-1 1-MCP for 12 h, dipped with 0.5 % chitosan, 5 µl l^-1 1-MCP combine with 0.5 % chitosan and untreated (control) then stored at 10°C. Application of chitosan coating delayed electrolyte leakage (EL) while1-MCP maintained firmness, EL and extended storage life at 32 days after storage. Therefore, using application of 1-MCP in mango at 10°C is a feasible technology for maintains quality and prolongs storage life in order to expand marketability and export options.

Abstract: This paper studied the effects of different fermentation media containing different kinds of agricultural products on Hypsizygus marmoreus polysaccharides production under the liquid culture condition, and the antitumor and antioxidant activity of the polysaccharides. The results indicate that when cultured in No. 45 fermentation medium, the intrapolysaccharide (IPS) production obtained from mycelia is the highest production 2.045 g/l, and the exopolysaccharide (EPS) production is the second highest with 1.960 g/l. The antitumor activities of EPS and IPS obtained from No.45 fermentation medium are the highest with inhibition rate of 39.89% and 56.25% against human gastric cancer cell line SGC-7901 respectively, which are higher than the positive control 5-Fu. The capacity of total antioxidant of EPS obtained from No. 39 fermentation medium is the highest with 0.813U/mg. The capacity of anti-superoxide anion radical of EPS obtained from No. 40 fermentation medium is the highest with 22.554U/g.