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111.
Hare Krishna R.K. Sairam S.K. Singh V.B. Patel R.R. Sharma Minakshi Grover Lata Nain A. Sachdev 《Scientia Horticulturae》2008
The in vitro performance of mango shoot culture is delimited by several factors, of which explant necrosis and media browning are considered as major constraints for successful exploitation of such an important commercial crop. Our results showed that source of explants had a significant effect on the performance of in vitro cultures of mango. The variations in survival of explants collected from glasshouse grown seedlings and field-grown stock plants indicated towards differences between their physiological/ontogenic age. Though, chronologically, both are young, the glasshouse grown shoots are ontogenetically younger and; therefore, responded better over field-grown shoots. Improved performance of explants harvested from mycorrhizal plants suggests integration of mycorrhizal biotechnology with tissue culture biotechnology in order to achieve better results as mycorrhiza being a well-known stress alleviator may help explants mitigate in vitro stresses. Furthermore, shoot tip explants of field-grown ‘Amrapali’ mango was assayed for their browning propensity at pre- and post-culture stages. Status of different bio-chemicals such as in vivo phenol, in vitro phenol exudation, phenylalanine ammonia lyase, peroxidase and polyphenol oxidase as affected by various pre-treatments were estimated to establish the relationship of these bio-chemicals with necrosis of mango shoot cultures. The different pre-treatments comprised etiolation of newly emerged shoots (5–7 days old) of stock plants using black polythene for 7 days, etiolation treatment + agitation of explants in antioxidant solution (antioxidants: ascorbic acid at 100 mg l−1 + citric acid at 50 mg l−1), etiolation treatment + agitation of explants in polyvinylpyrrolidone solution (PVP) at 0.2% and non-etiolated control. Of these, explants treated with PVP proved to be superior to other treatments with regards to explant necrosis percentage as such explants exhibited least activities of phenols and oxidative enzymes. Correlation studies indicated existence of high positive correlation between explant necrosis and these bio-chemicals. 相似文献
112.
Improvement mechanism of bondability in UF-bonded reed and wheat straw boards by silane coupling agent and extraction treatments 总被引:4,自引:0,他引:4
The effects of silane coupling agents and extractives on the wettability of reed and wheat straws were investigated. The inherent wettability of these materials was low but could be significantly improved by treating with silane coupling agents. The degree of improvement achieved by each silane coupling agent was different: Vinyl silane had almost no effect on wettability, epoxide silane was found to be more effective for reed straw, and amino silane was better for wheat straw. The wettability of these materials could also be improved by ethanol-benzene extraction, which resulted in more improvement in wheat straw than reed straw. The analyses of untreated reed and wheat straws by electron spectroscopy for chemical analysis (ESCA) revealed that there was much silicon on both the outer and inner surfaces of the former but only on the outer surface of the latter. The influence of hot-water extractives and silane coupling agents on the gelation time and pH of urea formaldehyde (UF) resin was also examined. The addition of extractives was found to increase the gelation time. Amino silane greatly retarded the gelation of OF resin, whereas epoxide and vinyl silanes had no influence on resin gelation. This retardation was found to be due to an increase in the pH of the resin. 相似文献
113.
多元羧酸类化合物对木材大压缩量变形的固定作用 总被引:5,自引:0,他引:5
以多元羧酸类化合物为酯化剂、以无机盐类为催化剂的交联体系是一类新型的水溶性、无毒害、无污染、木材交联反应未采用过的非甲醛系试剂交联体系。本文研究了这类非甲醛系试剂对木材大压缩量变形的固定作用,结果表明浓度9%的1,2,3,4丁烷基四羧酸处理大青杨试件,干状态的变形恢复率较低,沸水中变形恢复率接近于2701%。用1,2,3,4丁烷基四羧酸交联处理木材可以固定压缩变形,适宜的树脂浓度为9%。材色由偏红向偏黄方向转变。 相似文献
114.
甲醛处理对豆饼干物质和蛋白质瘤胃降解率及胃蛋白酶消化率的影响 总被引:3,自引:1,他引:2
豆饼用2g/kgDM甲醛处理后,10h瘤胃干物质(DM)降解率从87.19%下降到豆饼含水量为14%和60.93%和含水量18%时的56.29%,粗蛋白降解率从87.69%分别下降到48.36%和43.43%,随着甲醛用量的增加,干物质的粗蛋白的降解率进一步下降,但下降幅度减少。在甲醛用量低于2g/kgDM的情况下,甲醛用量对PH为4.5时的胃蛋白酶4h和8h干物质和粗蛋白消化率没有明显影响,但 相似文献
115.
116.
水产食品中甲醛风险评估研究进展 总被引:1,自引:0,他引:1
甲醛对人的呼吸、致敏和免疫、神经、内分泌系统均有影响,并有生殖毒性和致癌作用.本文主要从水产食品安全角度,根据风险评估理论,从甲醛对人体健康的危害、暴露评估、风险评估结果的不确定性和风险管理措施诸方面,探讨甲醛与人体健康之间的关系,综述水产食品中甲醛危害风险评估的研究进展. 相似文献
117.
微波法制玉米秸秆活性炭工艺条件及性能研究 总被引:2,自引:0,他引:2
以玉米秸秆为原料、ZnCl2为活化剂、微波为能源制备活性炭,通过正交试验,获得制备玉米秸秆活性炭的最佳工艺条件。将产品应用于甲醛气体的去除,并与市售活性炭进行了性能比较。发现在甲醛浓度为1.94-1.97mg/m^3的条件下,试验产品的穿透时间(tB)为12min,比市售活性炭提高20%,且吸附速度更快。 相似文献
118.
Rice sheath blight is an important disease caused by Rhizoctonia solani. The resistant and susceptible rice lines (32R and 29S, respectively) showed different responses to R. solani infection in metabolite levels. The aim of this study was to characterize the metabolite levels in rice lines during R. solani infection using capillary electrophoresis equipped with time of flight mass spectrophotometry (CE/TOF-MS) in positive ion mode. Hundred metabolites were identified and classified into six clusters by hierarchical cluster using Mass Profiler Professional software. Changes in metabolite level at inoculated 32R and 29S were mapped on branches of tricarboxylic acid and glycolysis pathway. Volcano plot successfully filtered the metabolites based on fold change and p-value. The volcano plot result showed that 10 metabolites were up and down regulated in inoculated 32R relative to 29S. One metabolite, chlorogenic acid, showed a positive response in 32R. Meanwhile, pipecolic acid showed as the highest magnitude of fold change and p-value significance level in 29S. In addition, eight amino acids; glutamate, γ-aminobutyric acid, glycine, histidine, phenylalanine, serine, tryptophan, and tyrosine showed increase in 29S after R. solani inoculation. 相似文献
119.
以未褐化的岩黄连愈伤组织为材料,于培养基中添加不同浓度的抗坏血酸,研究抗坏血酸对岩黄连愈伤组织褐化及总酚含量和多酚氧化酶活性的影响。结果表明:在培养第20天,各处理岩黄连愈伤组织的褐化率均低于对照;各处理的多酚氧化酶活性均高于对照,其中抗坏血酸浓度175mg/L的处理多酚氧化酶活性最高,为14.1400U/(g·min),比对照高72.3%;各处理的总酚含量均低于对照,抗坏血酸浓度为175mg/L的处理总酚含量最低,为0.4633μg/mL,比对照低88.3%。相关性分析结果表明,岩黄连愈伤组织褐变率与总酚含量呈正相关,与多酚氧化酶活性呈负相关;而岩黄连愈伤组织多酚氧化酶活性和总酚含量呈极显著负相关。 相似文献
120.