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101.
[目的]测定菠萝蜜不同种质成熟果实的可溶性总糖和淀粉含量,了解现有种质群体果实中可溶性总糖含量与淀粉含量之间的关系。[方法]以39份菠萝蜜种质为材料,其中4份分别在2次不同的时间取样1次,采用蒽酮比色法测定菠萝蜜果实中可溶性总糖含量和淀粉含量。[结果]当可溶性总糖含量在16.00%~20.00%时,淀粉含量在0.36%~4.46%;当可溶性总糖含量在20.01%~25.00%时,淀粉含量在0.42%~3.61%;当可溶性总糖含量在25.01%~30.00%时,淀粉含量在0.28%~3.10%;当可溶性总糖含量在30.01%~35.05%时,淀粉含量在2.08%~2.78%。在不同时间取样的4份种质中,后取样种质的可溶性总糖和淀粉含量相比先取样种质稍有下降。[结论]菠萝蜜果实中可溶性总糖和淀粉在一定含量范围内呈正相关关系。 相似文献
102.
103.
小麦新品种烟农5158及其亲本旗叶生理特性研究 总被引:1,自引:0,他引:1
在盆栽条件下,以小麦新品种烟农5158及其亲本鲁麦14号、烟农15号和烟航选2号为材料,研究烟农5158旗叶生理特性与亲本之间的差异.结果表明,烟农5158及其亲本旗叶净光合速率均在开花期达到最大,之后逐渐下降,在生育后期差异显著,烟农5158旗叶净光合速率始终高于其亲本.与亲本相比,烟农5158旗叶中抗氧化酶SOD、POD和CAT活性在生育后期下降缓慢且维持较高水平;烟农5158及其亲本旗叶中的SOD、POD和APX活性均随生育进程推进呈先升高后降低的趋势;花后7~28 d,烟农5158旗叶中POD活性显著高于其亲本.烟农5158与其亲本相比具有较高的可溶性蛋白含量,生育后期具有较低的MDA含量.烟农5158在生育后期具有叶片衰老缓慢、净光合速率高、抗逆性强的特点,这可能与它开花后旗叶中抗氧化酶活性较高、可溶性蛋白含量较高和MDA含量较低有关. 相似文献
104.
The effect of particle size of hull-less barley (HLB) bran DF on antioxidant and physicochemical properties was investigated. HLB bran and extracted DF was ground by regular and superfine grinding, their particle sizes were determined using laser diffraction method. The results showed that superfine grinding could significantly pulverize DF particles to micro-scale; the particle size distribution was close to a Gaussian distribution. The soluble DF in HLB bran was increased effectively with superfine grinding. Insoluble DF with submicron scale showed increased total phenolic content (TPC), DPPH radical scavenging activity and ferric reducing antioxidant power (FRAP). With particle size reduction, the water retention capacity (WRC), swelling capacity (SC), oil binding capacity (OBC), and nitrite ion absorption capacity (NIAC) were significantly (p < 0.05) increased and the water holding capacity (WHC) had no significant change. A kind of health beneficial DF with higher soluble DF content, WRC, SC, OBC, NIAC and antioxidant activity was obtained using superfine grinding. 相似文献
105.
Brewer's spent grain (BSG), the most abundant brewing by-product, has hidden and underexploited nutritional potential. In order to valorize BSG, the effects of three commercial xylanases and a peptidase on water unextractable arabinoxylans (WUAX) were studied. Comparing all treatments, higher addition of xylanase resulted in an increase in water extractable arabinoxylans (WEAX). In the most efficient treatment, xylanase alone was able to solubilise 23.7% of WUAX, while the peptidase showed no effect. However, when added together with xylanase, peptidase increased the solubilisation of WUAX up to 1.6 folds. A positive correlation between particle size reduction and solubilisation of WUAX was also proved through milling BSG. These results suggest that access to xylan backbone increases with proteolytic activities, proving a synergistic effect of these specific enzymes. Therefore, if properly treated before being added as ingredient, BSG could add health functionalities to foodstuff while reducing the environmental impact of brewing industries. 相似文献
106.
Soil chemical and biochemical properties of a salt-marsh alluvial Spanish area after long-term reclamation 总被引:2,自引:0,他引:2
Vito Armando Laudicina Maria Dolores Hurtado Luigi Badalucco Antonio Delgado Eristanna Palazzolo Michele Panno 《Biology and Fertility of Soils》2009,45(7):691-700
Marisma, one of the largest salt-marsh alluvial areas in SW Spain, has been reclaimed since 1970 by artificial drainage and
amendment with phosphogypsum (PG) so as to reduce Na+ saturation. Within the reclaimed area, two 250- × 20-m plots were treated as follows: (1) amendment with 25 Mg/ha of PG every
2 to 3 years between 1979 and 2003 (plot PY); (2) like PY but PG treatment stopped after 1997 (plot DR). A contiguous virgin
Marisma salt-marsh plot (MV), neither drained nor amended, was the control. In MV, soil microbial biomass C, most enzyme activities
and total organic C content were much greater than in PY and DR soils, despite the salinity stress. The decrease in soil organic
matter content in PY and DR soils was likely due to cotton-cropping practices, which favoured the organic C mineralisation
and nutrients removal by crops. Microbial activity of MV soil, probably stimulated by the rhizodepositions of the natural
vegetation, did not suffer from the osmotic effect due to the raising of soil solution ionic strength. Microbial quotient
could be ranked as MV > PY > DR, whereas the metabolic quotient had an opposite trend. Thus, both quotients suggested that
the interruption of PG amendment was not favouring microbial activity. Principal component analysis clearly identified the
chemical and biochemical soil properties mostly affected by the reclamation and also indicated the longer PG amendment in
PY plot. Stepwise discriminant analysis identified two physiologically different types of soil microflora, one less active
present in the MV virgin soil and another more active present in the reclaimed PY and DR soils. 相似文献
107.
108.
109.
不同苜蓿品种对豌豆蚜的生化抗性机制 总被引:4,自引:2,他引:2
采用紫外分光光度法和高锰酸钾法测定了不同抗蚜性苜蓿(Medicago sativa L.)品种受豌豆蚜(Acyrthosiphon pisum Harris)为害胁迫后叶片内叶绿素(Chl)、可溶性蛋白、总酚含量及防御性酶多酚氧化酶(PPO)和过氧化氢酶(CAT)活性的动态变化,以期明确各项生理指标与抗虫性之间的关系。结果表明:在蚜虫刺吸诱导过程中,4个品种的PPO均呈先下降后上升的趋势,其中接蚜前抗虫品种甘农5号(G5)PPO活性高于感虫品种猎人河(Hu)和低抗品种甘农3号(G3)、金皇后(JH),接蚜后迅速下降,其活性低于感虫品种;抗虫品种甘农5号CAT活性和总酚含量始终高于低抗品种和感虫品种;感虫品种(Hu)Chl含量高于低抗品种(G3,JH),但低于抗虫品种(G5);感虫品种和抗虫品种的可溶性蛋白含量低于低抗品种(除第3 d高于G3);4个品种的CAT活性、Chl含量、可溶性蛋白含量均呈下降趋势。因此,苜蓿品种的Chl、可溶性蛋白、PPO与其对豌豆蚜抗性的相关性不明确,而总酚、CAT与抗蚜性呈正相关。 相似文献
110.
延安人工林地土壤可溶性有机氮(SON)含量分析 总被引:1,自引:0,他引:1
[目的]为了解SON(可溶性有机氮)在延安燕沟流域土壤中的分布行为提供理论依据。[方法]以刺槐林(15年)、刺槐林(5年)、灌木林(拧条)、苹果林(3年)、侧柏林(15年)等人工林地为研究对象,研究不同林地土壤中SON含量的差异。[结果]不同类型林地土壤SON含量不同,且差异显著。具体为:刺槐林(15年)〉灌木林(拧条)〉侧柏林(15年)〉刺槐林(5年)〉苹果林(3年)。林地土壤提取液中SON的平均含量为19.24 mg/L,高于谷子地(15.85 mg/L)土壤提取液。林地土壤SON含量平均占其总可溶性氮含量的68%以上,不同类型林地比较,林地土壤SON含量平均占其总可溶性氮含量的比例为:刺槐林(15年)〉侧柏林(15年)〉灌木林(拧条)〉刺槐林(5年)〉苹果林(3年)。[结论]人工造林增加了土壤中的SON含量。林地土壤的SON组分不容忽视。 相似文献