Gene response in rice plants treated with continuous fog influenced by pH,was similar to that treated with biotic stress

Background

Throughout Asia, including Japan, rice plants are cultivated in a wide range of areas from lowlands to highlands and are frequently exposed to fog, including acid fog. Some physiological studies have shown that acid fog can be a stress factor for plants. We analyzed the gene expression profiles of rice plants treated with artificially prepared simulated acid fog (SiAF) or simulated neutral fog (SiNF) for 1 or 7 days.

Results

Microarray analysis results suggested that both the SiAF and the SiNF treatments induced the expression of genes involved in the defense and stress responses in rice plants. Induction of such genes was detected in plants treated with SiAF for 1 day, and the number of induced genes increased in plants treated with SiAF for 7 days. The genes for defense and stress responses were also induced by SiNF for 7 days, although they were not induced by SiNF for 1 day. The gene expression profiles of the SiAF-treated and the SiNF-treated plants were compared to those of plants treated with other stress factors. The comparison revealed that both SiAF and SiNF treatments have similar effects to biotic stresses and ozone stress. The genes encoding NADPH oxidase and germin, which function in apoplasts, were also induced by SiAF, SiNF and biotic stresses.

Conclusions

These findings suggest that both the SiAF and the SiNF treatments may result in oxidative stress through the apoplastic production of reactive oxygen species.     

酸性磷酸酶在萌发大豆种子中子叶细胞壁上的分布

本文应用光镜，电镜酸性磷酸酶的细胞化学定位法，对大豆种子萌发过程中酸性磷酸酶在子叶细胞壁上的分布进行了详细的观察与分析。大豆种子吸水膨胀１天时，子叶细胞的胞间层首先表现出酸性磷酸酶的活性；播种１－２天后，除胞间层外，胞间隙也表现了酸性磷酸酶的活性；播种４－６天期间，酸性磷酸酶不仅在胞间层，胞间隙处表现出活性，而且在细胞壁及质膜上也表现出较强的活性。根据本文的观察结果我们推测，萌发的大豆子叶细胞壁上     

Nutritional characteristics of the leaves of native plants growing in adverse soils of humid tropical lowlands

Acid sulfate, peat, sandy podzolic, and saline soils are widely distributed inthe lowlands of Thailand and Malaysia. The nutrient concentrations in theleaves of plants grown in these type of soils were studied with the aim ofdeveloping a nutritional strategy for adapting to such problem soils. In sagoand oil palms that were well-adapted to peat soil, the N, P, and Kconcentrations were the same in the mature leaves, while the Ca, Mg, Na,and Fe concentrations were higher in the mature leaves of the oil palm thanof the sago palm. Melastoma malabathricum and Melaleuca cajuputi plantsthat were well-adapted to low pH soils, peat, and acid sulfate soils were alsostudied. It was observed that a high amount of Al accumulated in the M.marabathricum leaves, while Al did not accumulate in M. cajuputi leaves.M. cajuputi plants accumulated large amounts of Na in their leaves or stemsregardless of the exchangeable Na concentration in the soil, while M.malabathricum that was growing in saline-affected soils excluded Na.Positive relationships between macronutrients were recognized between Pand N, between K and N, and between P and K. Al showed antagonisticrelationships with P, K, Ca, Mg, Fe, Zn, Cu, and Na. Na also showedantagonistic relationships with P, K, Zn, Mn, Cu, and Al. Fe showed weakantagonistic relationships with Zn, Mn, Cu, and Al.     

饲粮中添加叶酸对乐平母猪繁殖性能的影响

本研究选用本地猪种乐平花猪以探讨饲粮中添加叶酸对繁殖母猪的作用效应。２７头经产母猪根据年龄、胎次与系祖来源随机分为３个处理组，即在妊娠和哺乳期基础日粮中分别添加叶酸０（作为对照）、２ｍｇ／ｋｇ和６ｍｇ／ｋｇ。结果表明：添加叶酸提高了总窝产仔数、窝产活仔数及４０日龄育成数（Ｐ＜０．１或Ｐ＜０．０５），尤其是添加叶酸６ｍｇ／ｋｇ组的总窝产仔数和窝产活仔数分别提高了１．８９头和１．３４头；３个处理组的仔猪平均初生体重没有明显差异（Ｐ＞０．２５），但是初生窝重及４０日龄断奶窝重随着补充叶酸的增加而明显地增加（Ｐ＜０．１或Ｐ＜０．０１）。虽然各处理组的母猪在繁殖周期各阶段的体重没有变化（Ｐ＞０．２５）。，但添加叶酸组母猪的孕期增重及哺乳期掉膘却趋向于增加，且母猪妊娠期的增重愈多，其哺乳期掉膘亦愈多。本研究结果证明，在母猪妊娠和哺乳期基础饲粮中添加适宜剂量的叶酸，通过增加其窝产活仔数可以进一步发挥乐平母猪较高的生产性能     

喹诺酮类(吡哌酸、诺氟沙星)药物的热分解特性研究

分别采用差示扫描量热法(DSC)、热重法(TG)和微分热重法(DTG),研究了喹诺酮类(吡哌酸、诺氟沙星)抗菌药的热分解动力学过程,计算了其热分解动力学参数——活化能(E),分析了其热分解机理,并剖析了喹诺酮类药物有机结构上的差异。     

粤西砖红壤的镁素状况及其有效性

研究结果表明,粤西砖红壤的全镁含量普遍较低,玄武岩和花岗岩发育的土壤,全镁含量多在0.2％以下,浅海沉积物发育的土壤,全镁不足0.1％,玄武岩发育的土壤,交换性镁较丰,表土含量均在100ppm以上,镁饱和度较高;浅海沉积物和花岗岩发育的土壤,交换性镁贫缺,表土平均含量分别为16.7和14.7ppm,镁饱和度大都极低.土壤供镁能力的强弱依次是:玄武岩发育的砖红壤>浅海沉积物发育的砖红壤>花岗岩发育的砖红壤。交换性镁及镁饱和度与牧草的相对产量、吸镁量以及玉米小苗的含镁量、吸镁量的相关性达显著或极显著水平。据此初步认为可用作土壤镁素诊断指标。酸深性镁的有效性也较高,但因其释放速度较慢,不宜作为诊断指标,可用以评价土壤有效镁的补充能力。     

磷胁迫下蔗糖对水稻苗期根适应性和磷酸转运蛋白基因表达的影响

磷是植物生长和发育中最重要的必须元素之一。尽管土壤中磷资源很丰富,但大部分磷是以植物不能吸收利用的固定态和有机态存在,特别是以酸性土壤为主的南方稻田,水稻缺磷现象非常严重。理解和掌握水稻对低磷的适应机制有助于利用分子手段培育磷高效利用水稻品种。为阐明蔗糖提高水稻耐低磷的机制,本研究对水稻幼苗进行不同磷、糖处理,分析水稻幼苗在不同磷糖配比培养基中的根系结构、无机磷、酸性磷酸酶活性的变化,并利用定量RT-PCR技术分析水稻磷酸转运蛋白基因(OsPT)和酸性磷酸酶基因(OsSAP1)的表达。试验设2个磷浓度:无磷和85 mg·L?1KH2PO4,2个蔗糖浓度:无糖和3%蔗糖,正交设计。结果表明,在低磷胁迫时添加蔗糖,能使水稻幼苗的根总长度、总根数、根冠比显著增加,根分泌的酸性磷酸酶活性降低,但水稻体内的磷酸转运酶活性提高。11个与磷具有高度亲和力的磷酸转运酶的表达发生了改变,其中根优势表达的4个基因OsPT2、OsPT3、OsPT4、OsPT6对磷、糖的影响最为敏感,暗示了蔗糖是通过调节磷转运蛋白维持磷的吸收和平衡。增加根系的蔗糖分配能够提高水稻幼苗对磷胁迫的耐受性。     

Quantitative Measurement of Organic Carbon in Mine Wastes: Methods Comparison for Inorganic Carbon Removal and Organic Carbon Recovery

The present study aims to evaluate carbon recovery and analytical precision of two methods based on dry combustion for organic carbon (OC) quantification in base metal mine tailings: (1) IC subtraction method (inorganic C(IC) measured and subtracted from total C) and (2) direct OC quantification after acid pretreatment. Results showed IC subtraction method effectively hydrolyzed a range of IC minerals [calcium carbonate (CaCO₃), magnesium carbonate (MgCO₃), dolomite, magnesite, calcite] with satisfactory IC (as CO₂ released) recovery (87–103 percent). In the direct OC quantification method, 5 M hydrochloric acid (HCl) pretreatment resulted in a satisfactory recovery (76–92 percent) of most organic compounds [ethylenediaminetetraacetic acid (EDTA), cellulose, plant litter, and charcoal], except for water-soluble OC (sucrose, 40 percent recovery). The precision of both methods declined when C levels were <5 g kg^?1 with RSD (Relative Standard Deviation) > 10 percent. The OC values in test samples of base metal mine tailings were comparable between the two methods. However, IC subtraction method is not applicable for tailings with low OC levels (<5 g kg^?1) until the precision is substantially improved. Moreover, compared to the IC subtraction method, OC values are significantly lower in direct OC quantification method for tailings with high OC levels.     

外源镁对强酸性紫色土壤阳离子交换效应的研究

[目的]为研究外源镁对强酸性紫色土壤阳离子交换效应。[方法]选择重庆地区强酸性紫色土壤为对象,采用1：5的土水比,用10emol（＋）／LMgSO4溶液对土壤进行多次交换处理。[结果]在实验条件下,外源镁能快速取代土壤胶体上吸附的各种盐基离子,但对致酸离子（H＋、A1＋）则难以达到快速、完全取代,经5次交换后,盐基饱和度由46．6％上升至72．4％,土壤pH仅上升0．7个单位;Mg2＋与Ca＋、Na＋的交换分别可以用指数方程Y=14．998e-1．4849x（R2=0．9938）、二次方程Y=0．011 1x2-0．1005x＋0．233（R‘=0．986）进行很好地拟合;Mg“与K’的交换后期明显表现出有部分土壤次生黏土矿物层间固定的K’会被交换出来,导致被交换出的K’总量增加。[结论]在无酸碱中和的条件下,外源钱可以改变土壤胶体盐基离子的构成,但对于改良强酸性土壤并无实际意义,反之,过量的外源镁还可能造成土壤其他盐基离子的损失。     

2007～2013年丹东地区酸雨特征及成因分析

根据丹东2007 ～2013年的酸雨监测资料,对近年来该地区酸雨的时空分布特征进行了总结与分析,研究了不同气象条件对降水酸度的影响,分析了酸雨形成的原因.结果表明,丹东降水酸度呈波动性变化;2007 ～ 2013年降水平均pH年平均范围为4.82～5.51,pH均小于5.60,且自2008年以来,呈现波动下降的趋势;pH有明显的季节变化,以夏季酸度为最强、秋季为最弱;出现频率以秋季最高,为43.3％,春季最低,为30.1％.丹东酸雨的形成是该地区的自然和人为因素共同作用的结果,气象条件的变化对降水酸度影响相当明显,丹东市当地地形、工业布局和外来源也为酸雨形成做出了较大贡献.