盐胁迫对野生稻种子萌发及幼苗生长的影响

以3个野生稻品种(系)和常规稻品种吉粳301(CK)为试验材料,研究了不同NaCl浓度对野生稻种子萌发及幼苗生长的影响。结果表明,盐胁迫对野生稻和常规粳稻种子萌发及幼苗生长的影响不同,NaCl浓度≤0.3%时,盐胁迫对3个野生稻种子发芽及幼苗生长没有影响,但促进吉粳301种子发芽及幼苗生长;NaCl浓度≥0.5%时,随着NaCl浓度的增大,3个野生稻种子发芽率逐渐降低,幼苗的根长、苗长、根冠比逐渐变小;NaCl浓度与3个野生稻种子发芽率有一定的负相关性;NaCl对野生稻幼苗根的抑制作用强于对苗的作用;不同野生稻品种对NaCl溶液的耐受能力不同,从大到小依次为MY-3、延引红、HY-1。     

西农538 LMW-GS基因的克隆、原核表达及功能鉴定

为了探索普通小麦品种西农538的LMW-GS对面粉加工品质的影响,根据NCBI中已公布的LMW-GS基因序列,设计了一对特异性引物,从西农538基因组DNA中克隆出LMW-GS基因后,对其进行原核表达及掺粉试验。序列分析表明,克隆得到的LMW-GS基因序列(GenBank登录号为KX452081)有单一完整的开放阅读框,编码区长915bp,无内含子。同源性比对及进化树分析发现,该基因属于Glu-D3、Type V(Group 10)、m型、C组LMW-GS基因。SDS-PAGE和Western blot分析表明,该基因原核表达成功。微量掺粉试验表明,诱导表达的蛋白对小麦面粉加工品质有负效应。     

小麦旗叶大小及穗部相关性状的QTL定位

为了发掘更多控制小麦旗叶大小及穗部相关性状的QTL,以兰考906和小偃81创制的133个F6~F7重组自交系为试验材料,在6个环境下利用SSR标记对旗叶大小及穗部相关性状进行QTL定位。结果表明,有202对SSR标记被用于构建遗传连锁图谱,图谱覆盖小麦21条染色体,全长1 678.93cM,标记间平均距离8.30cM。采用完备区间作图法共检测到30个QTL,分布在1B、2A、3D、4A、4B、4D、5D、6A、6B、6D和7D染色体上。其中,旗叶宽QTL有7个,穗长QTL有9个,小穗数QTL有5个,穗粒数QTL有5个,小穗着生密度QTL有4个,不同环境下单个QTL可解释的表型变异率为4.94%~23.14%,有14个QTL的表型贡献率大于10%,有8个QTL可在2个或2个以上环境中被检测到。其中,Qflw-4A在3个环境中被检测到,贡献率为10.13%~20.77%,是控制旗叶宽的稳定主效QTL;Qsl-4D.2在4个环境中被检测到,贡献率为12.58%~23.14%,是控制穗长的稳定主效QTL;Qker-5D在2个环境中被检测到,贡献率为11.44%~14.32%,是控制穗粒数的稳定主效QTL。这3个稳定主效QTL可作为改良叶宽和增加穗粒数的功能QTL作进一步研究。     

Explaining urban governance in the midst of political transformation: The city of Macao

This paper takes a close look at the urban governance and political culture of Macao, the world largest casino city. Macao has experienced spectacular economic growth since gaming liberalisation in 2002 and China's Free Individual Travel scheme launched in 2003. However, the booming gaming sector has crowded out other sectors of Macao. It has not only made the city's economy mono‐structured and consequently extremely vulnerable to external shocks and fluctuations but also induced serious social divisions and political controversies within the local community. By tracing the root cause of the ongoing dilemma and crisis in the mode of governance, the dynamic relationships between formal and informal institutions, consensus politics and the social group culture are intensively discussed in a historical context. In fact, the sustainable development of the former Portuguese colony has largely been hindered by its residents' passive attitudes toward political communication, non‐transparent urban governance, the absence of a middle class and the dominance of pro‐establishment social groups.     

粮食污染物残留免疫分析技术研究与示范

随着人们对粮食安全问题的重视,政府部门不断加强对粮食安全的监测工作。针对粮食生产、加工、储运过程中的化学污染物安全性问题,研究粮食污染物快速监测技术,研究污染物免疫分析方法通过利用抗原、抗体的特异性反应来检测农药含量,设计并筛选吡虫啉、多溴联苯醚、功夫菊酯、氰戊菊酯4种半抗原,制备相关高特异性的抗体,分析吡虫啉、多溴联苯醚、功夫菊酯与气相色谱法(GC)相比,稻谷、大米、玉米样品通过相关性分析均高度相关,操作简便、快速。     

花期低温对水稻叶鞘生理及结实率的影响

盆栽条件下,以耐冷性不同的2个水稻（Oryza sativa L.）品种龙稻5（耐冷型）和龙粳11（冷敏型）为材料,于开花期在人工气候室进行低温（15℃,分别持续1,2,3,4,5 d）处理,研究开花期低温对不同耐冷性水稻结实率及叶鞘膜透性、抗氧化酶等生理指标的影响。结果表明：低温处理2 d时,龙稻5和龙粳11的花粉活力分别下降了8.21%和16.10%,差异达极显著水平;低温处理3 d后,龙稻5的结实率下降到99.90%,与CK相比差异达到显著水平;低温处理1 d后,龙粳11的结实率下降到60.04%,与对照相比差异达到极显著水平。低温处理提高了水稻叶鞘相对电导率和脯氨酸、可溶性蛋白含量,处理5 d时各指标达最大值,与CK相比,龙稻15和龙粳11分别提高了38.01%和20.77%、25.06%和84.85%、25.82%和23.63%。同时低温处理也提高了叶鞘超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性,处理3 d时酶活性达最大值,龙稻15和龙粳11分别较CK提高了10.57%和14.90%、86.26%和68.71%、17.73%和28.25%。综上所述,开花期低温引起水稻叶鞘膜脂过氧化程度升高,但也诱导水稻叶鞘抗氧化系统开启、保护酶活性上升以抵御低温伤害;开花期低温导致水稻花粉活力降低并引起结实率降低,耐冷品种较冷敏品种抵御能力强。     

The use of iron (III) ferrocyanide soil amendment for removing salt from the soil surface

Accelerated soil salinization is a worldwide concern. Our study was carried out to determine the effects of different rates (0, 5, 10, and 15?mmol kg^?1) of iron (III) ferrocyanide application to remove salts from the soil. Within two weeks of its application, iron (III) ferrocyanide at 5, 10, and 15?mmol?kg^?1 removed 12.2%, 26.5%, and 42.9% of the total salts from the soil, respectively. Results suggested that iron (III) ferrocyanide application at 15?mmol?kg^?1 is one of the most rapid and effective ways to remove substantial amounts of salts from undrained soil (land) where fresh water is scarce.     

Separating the effects of habitat amount and fragmentation on invertebrate abundance using a multi-scale framework

Context

Herbicide treatments in viticulture can generate highly contrasting mosaics of vegetated and bare vineyards, of which vegetated fields often provide better conditions for biodiversity. In southern Switzerland, where herbicides are applied at large scales, vegetated vineyards are limited in extent and isolated from one another, potentially limiting the distribution and dispersal ability of organisms.

Objectives

We tested the separate and interactive effects of habitat amount and fragmentation on invertebrate abundance using a multi-scale framework, along with additional environmental factors. We identified which variables at which scales were most important in predicting patterns of invertebrate abundance.

Methods

We used a factorial design to sample across a gradient of habitat amount (area of vegetated vineyards, measured as percentage of landscape PLAND) and fragmentation (number of vegetated patches, measured as patch density PD). Using 10 different spatial scales, we identified the factors and scales that most strongly predicted invertebrate abundance and tested potential interactions between habitat amount and fragmentation.

Results

Habitat amount (PLAND index) was most important in predicting invertebrate numbers at a field scale (50 m radius). In contrast, we found a negative effect of fragmentation (PD) at a broad scale of 450 m radius, but no interactive effect between the two.

Conclusions

The spatial scales at which habitat amount and fragmentation affect invertebrates differ, underpinning the importance of spatially explicit study designs in disentangling the effects between habitat amount and configuration. We showed that the amount of vegetated vineyards has more influence on invertebrate abundance, but that fragmentation also contributed substantially. This suggests that efforts for augmenting the area of vegetated vineyards is more beneficial for invertebrate numbers than attempts to connect them.