中国青凤蝶3个亚种的遗传变异分析

[目的]探讨中国青凤蝶(Graphium sarpedon Linnaeus)3个亚种的遗传变异。[方法]对青凤蝶3个亚种的COⅠ基因和EF-1α基因部分序列进行测定,并对序列的碱基组成、转换颠换数和遗传距离等进行分析。[结果]在测得的COⅠ基因(709 bp)和EF-1α(1 064 bp)基因中,有44个变异位点,6个简约信息位点,COⅠ基因A+T平均含量为69.3%,存在较强的含量偏向性,亚种间的遗传距离相差甚小。[结论]青凤蝶3个亚种之间没有明显序列差异,仍然适宜采用传统的基于形态学的青凤蝶亚种分类体系。     

晋西黄土区封禁小流域植被群落特征变化

对晋西黄土高原封山育林小流域内植被覆盖度、群落木本植物组成及群落α多样性变化进行研究,为黄土高原地区仿拟自然植被的恢复与构建提供相应的理论依据和技术支撑。于2016年7—8月,以山西吉县蔡家川流域内实施封山育林35年的柳沟小流域为调查对象,采用样线与样方相结合的调查方法,对阳坡、半阳坡、阴坡、半阴坡、梁峁顶、沟底6种不同生境的植被状况进行了调查,并与1996年(封禁15年)、2007年(封禁26年)在柳沟小流域相同生境的调查数据进行对比,研究封山育林小流域随封育时间的延长植被覆盖度、群落木本植物组成、群落α多样性的动态变化规律。结果表明:1)小流域封禁15、26、35年时总体覆盖度分别达到77.5%、89.1%和93.6%,封禁26年时小流域已形成森林植被,到封禁35年时各生境的植被恢复较好,流域已基本郁闭;封禁26年后流域总体覆盖度的年增长率放缓,其中阳坡、梁峁顶覆盖度年均增长率减慢,半阴坡、阴坡的覆盖度增长速率仍在增加。2)封禁35年时半阳坡、半阴坡、梁峁顶由旱中生灌木群落向中生性乔灌群落演替,阳坡由旱中生乔灌群落向中生性乔灌群落演替,阴坡由喜阴的中生乔灌群落向中生性乔灌群落演替,沟底由旱中生乔灌群落向中生性灌木群落、湿中生乔灌群落演替。3)到小流域封禁35年,除阳坡外各生境的物种多样性呈现单峰变化,除阳坡外各生境的均匀度指数逐渐上升,生态优势度、物种丰富度波动变化。目前各生境群落处于中期演替阶段,物种分布更为均匀,结构更加稳定,在晋西黄土区封山育林是形成可持续森林植被的最好方法。      

Hyperglycaemia but not hyperlipidaemia decreases serum amylase and increases neutrophils in the exocrine pancreas of cats

The goal of the study was to determine whether hyperglycaemia or hyperlipidaemia causes pancreatitis in cats and to assess the effect of excess serum glucose and lipids on amylase and lipase activity. Ten-day hyperglycaemic and hyperlipidaemic clamps were carried out in five and six healthy cats, respectively. Ten healthy cats received saline and served as controls. The activity of amylase was below the normal range in 4 of 5 hyperglycaemic cats by day 10. The activity of lipase did not vary in any of the cats. Samples of exocrine pancreas were normal on histological examination, but the number of tissue neutrophils was increased in hyperglycaemic cats (P < 0.05). In a retrospective study 14 of 40 (35%) cats with naturally occurring diabetes mellitus had amylase activities below the reference range at the time of admission. Amylase activities normalised within 1 week of insulin therapy and subsequent glycaemic control. Lipase activity was increased in 26 of 40 (65%) diabetic cats and remained elevated despite glycaemic control. In conclusion, hyperglycaemia, but not hyperlipidaemia, increases pancreatic neutrophils in cats. However, because the histological morphology of the exocrine pancreas was normal, hyperglycaemia may play only a minor role in the pathogenesis of pancreatitis. Low amylase activities in diabetic cats may reflect an imbalance in glucose metabolism rather than pancreatitis.     

灌溉定额分月趋势确定法及其在旱作水稻上的应用

为了探索旱作水稻灌溉定额确定方法,通过对长系列(1992-2014年)单季稻生长季(6-10月份)及旱季(7-9月份)降雨量进行排频,并参考蒸发量确定不同灌溉保证率代表年;通过计算多年日均有效降雨量和水稻需水量,按月绘制成不同保证率的水稻需水量与有效降雨量变化趋势线图;通过积分法计算曲线方程差,即为月灌水额,合计后为灌溉定额,或通过测算曲线间的图形面积快速获得月灌水额。结果表明,当地单季水稻90%、75%和50%的年份能够满足的灌溉定额分别为416.9、338.7和216.1 mm,旱作水稻取其50%~60%的灌溉量值。应用试验表明,干旱年(2013年)按90%、平水年(2014年)按50%的年份能够满足的定额减半灌溉,粳稻旱作产量分别为5 924.3 kg·hm-2和6 511.8kg·hm-2,是淹灌栽培的84.1%和91.2%。该方法不仅能计算灌溉总量,还能体现灌溉量在作物生长过程中的分配趋势,对于提高旱作水稻的水分管理水平具有重要意义。     

Inhibitory action of Cerrado plants against mammalian and insect α-amylases

A total of 185 hexanic, dichloromethanic, ethanolic and hydroethanolic extracts from 24 species of Cerrado plants, were tested against Zabrotes subfasciatus, Acanthoscelides obtectus, and human saliva α-amylases. Twelve crude extracts presented inhibition rates greater than 80% against digestive α-amylases of the insect pest Z. subfasciatus, at a concentration of 1 mg mL⁻¹. These extracts were also tested against A. obtectus and human saliva α-amylases to verify their affinity and specificity of action. The hydroethanolic Kielmeyera coriacea stem bark extract presented a strong inhibitory potential, with IC₅₀ values of 110 μg mL⁻¹ for Z. subfasciatus and 272.12 μg mL⁻¹ for A. obtectus, in addition to a 97.09% reduction in enzyme activity of human saliva α-amylases at 125 μg mL⁻¹. The hexanic Aspidosperma macrocarpon root wood extract totally inhibited the activity of Z. subfasciatus α-amylases, reduced the enzyme activity of A. obtectus by 14.69% at 1 mg mL⁻¹, but did not alter the activity of human saliva α-amylases, thus characterizing greater inhibition affinity and specificity. The results suggest that the application of plant extracts against insect α-amylases represent a promising biotechnological tool for development of new insect pest control strategies, with noticeable affinity and specificity of action against different target enzymes.     

半干旱地区湿地生态系统植物α及β多样性分析

以哈巴湖自然保护区四儿滩湿地生态系统为例,采用样线调查方法研究半干旱地区湿地植物α及β多样性。结果表明:沿湿地-交错带-草原的生境梯度,α多样性变化较为明显。除均匀度指数外,其它多样性指数交错带均高于湿地及草原植被带,体现了群落交错带的边缘效应。不同方向α多样性测度结果表明,受地形、人为活动的影响,6条样线方向α多样性差异较大;β多样性测度结果和α多样性较为吻合,交错带与草原植被带的相似性系数最大,与湿地植被带的相似性系数次之,而草原植被带与湿地植被带的相似性系数最小。     

福州市主要公园乔木树种多样性分析

对福州市4个主要公园的乔木种类和各树种的个体数量进行调查,采用α多样性指数对各个公园乔木树种的调查结果进行分析,并应用二元属性数据的β多样性指数对各个公园乔木树种的多样性进行了初步研究。结果表明:4个公园内有乔木树种共196种,隶属54科97属;Simpson生态优势度指数表现为:闽江公园北园>闽江公园南园>温泉公园>西湖公园;Shannon-Wiener多样性指数表现为:闽江公园北园>温泉公园>闽江公园南园>西湖公园;Pielou均匀度指数表现为:闽江公园南园>闽江公园北园>温泉公园>西湖公园;Whittaker多样性指数表现为:温泉公园>闽江公园北园>西湖公园>闽江公园南园;Sorenson相似度指数表现为:闽江公园南园和温泉公园的Sorenson相似度指数最小,为0.39535,闽江公园北园和闽江公园南园最大,为0.63514。     

人工老化对大麦种子发芽特性及淀粉分解的影响

为探究大麦(Hordeum vulgare L.)老化种子在萌发过程中淀粉代谢的劣变机制,采用高温高湿(40℃、80%相对湿度)的人工老化处理方法,模拟大麦种子自然老化过程,研究老化处理对大麦(甘啤4号、垦啤7号、P12-8和9810)种子发芽特性及其萌发早期(0~72h)籽粒淀粉含量和淀粉酶活性的影响。结果表明:(1)随着老化时间的延长,4个大麦品种的发芽特性指标均呈现逐渐降低的趋势。(2)随着萌发时间的延长,4个大麦品种籽粒内支链淀粉和直链淀粉的含量均逐渐降低,α-淀粉酶和β-淀粉酶活性逐渐升高。相同萌发时间段随着老化程度的加深,籽粒内支链淀粉和直链淀粉的含量均呈现波动式增加;α-淀粉酶和β-淀粉酶活性均呈现降低的趋势;与对照相比,不同老化处理大麦籽粒的淀粉酶活性差异显著。(3)未萌发籽粒中检测不到α-淀粉酶活性,却检测到活性很小的β-淀粉酶。(4)萌发48~72h时,各大麦品种不同活力水平的籽粒内,淀粉含量和种子发芽特性指标均呈极显著负相关,淀粉酶活性和种子发芽特性指标均呈极显著正相关。     

The interaction between starch hydrolysis and acidification kinetic determines the quality of a malted and fermented sorghum beverage

Gowé is a traditional fermented Beninese soft cooked paste made from a blend of malted and non-malted cereals that is diluted with water/ice and sugar just before consumption as a thirst-quenching drink. Major differences in the processes used for the preparation of gowé, which includes natural lactic fermentation, result in variable quality. Acidity and free sugar content have been linked to the process parameters but also to the type of strains that can be used for inoculation. The aim of this study was to investigate the starch degradation mechanism in relation with the activity of degrading enzymes during the preparation of gowé and enzyme impact on the quality (sugar content and viscosity) of the final product. Our results point to a key role for malt α-amylase and its susceptibility to acidic conditions in the sequence of the preparation process and in the final quality of gowé. Pre-cooking and inoculation speeds up and increases acidification of the product thereby favoring its safety, but reduces the final free sugar content and increases the final viscosity of gowé, which are both organoleptic defects of the product.     

Ca2和Cu2+胁迫对小麦种子萌发的影响

[目的]研究不同浓度Ca2+、Cu2+胁迫对冬小麦(Triticum aestivum L.)新品系03132-6种子萌发情况的影响,为小麦抗盐生理研究和应用提供理论依据。[方法]Ca2+、Cu2+浓度均分别为0.05%、0.10%、0.15%、0.20%、0.25%、0.30%。[结果]同一离子条件下不同浓度Ca2+、Cu2+对小麦种子萌发有不同的影响,不同离子条件下同一浓度对小麦种子萌发影响也不同。Cu2+对小麦种子的萌发影响显著,Ca2+对小麦种子萌发的影响明显小于Cu2+。Ca2+浓度≤0.15%时,小麦种子的发芽势和发芽率有所提高,淀粉酶活力也有所提高;当其浓度≥0.20%时,小麦种子的发芽势和发芽率有所下降,淀粉酶活力也随之下降。当Cu2+浓度≥0.05%时,小麦种子发芽势、发芽率、淀粉酶活力都大幅度下降。[结论]0.05%～0.30%Cu2+能抑制小麦种子的萌发;0.05%～0.10%Ca2+对小麦种子的萌发有促进作用,0.15%～0.30%Ca2+对小麦种子的萌发有抑制作用。