Back to the Origins: Background and Perspectives of Grapevine Domestication

Domestication is a process of selection driven by humans, transforming wild progenitors into domesticated crops. The grapevine (Vitis vinifera L.), besides being one of the most extensively cultivated fruit trees in the world, is also a fascinating subject for evolutionary studies. The domestication process started in the Near East and the varieties obtained were successively spread and cultivated in different areas. Whether the domestication occurred only once, or whether successive domestication events occurred independently, is a highly debated mystery. Moreover, introgression events, breeding and intense trade in the Mediterranean basin have followed, in the last thousands of years, obfuscating the genetic relationships. Although a succession of studies has been carried out to explore grapevine origin and different evolution models are proposed, an overview of the topic remains pending. We review here the findings obtained in the main phylogenetic and genomic studies proposed in the last two decades, to clarify the fundamental questions regarding where, when and how many times grapevine domestication took place. Finally, we argue that the realization of the pan-genome of grapes could be a useful resource to discover and track the changes which have occurred in the genomes and to improve our understanding about the domestication.     

磷肥厂氟化物对周边农作物的危害与防治

对云南三环化工有限公司厂界周边农作物中氟化物含量进行常年的跟踪监测,分析氟化物排放对厂界周边农作物的危害。结果表明,氟化物污染危害程度与烟囱排放高度、气象条件、排放浓度及农作物本身抗性等因素有关,提出了氟化物污染的防治对策和建议。     

基于改进的SEBS模型的作物需水量研究--测试文章

为了探讨以蒸散发为基础的作物需水量情况，便于为农业生产提供数据支持，利用风云三号、风云二号气象卫星数据，结合自动站气象数据，基于改进的SEBS模型对山西省进行作物需水量研究。结果表明：通过与实测数据对比验证发现模型结果精度较高。山西省2012年3—9月全省日均作物需水量最大值出现在春季的5月份，为1.27 mm，其中，以单季作物为代表的晋东北和中西部日均作物需水量最大值均出现在5月，分别为1.05 mm和1.38 mm；以双季作物为代表的晋东南日均作物需水量最大值出现在5月和7月，分别为1.28 mm和1.23 mm。可见山西省作物需水量普遍以春季最大，其中尤以中西部突出，晋东北则相对最低。     

A rapid loop-mediated isothermal amplification method for detection of the modified GM cry1A gene in transgenic insect-resistant cotton and rice

Among the commercial genetically modified (GM) crops, the insect-resistant GM crops are the major cultivars that cry gene is introduced into. A cry1Ab/1Ac GM fusion gene (GFM cry1A) and a GM truncated cry1Ac gene (cry1Ac-Mon) is the key foreign gene employed for construction of GM crops by China researchers and Monsanto Technology LLC respectively. Here these two genes are entitled “GM cry1A” gene and a rapid visual loop-mediated isothermal amplification (LAMP) assay method for detection of GM cry1A in transgenic insect-resistant crops was established. The LAMP assay was performed at an optimal temperature of 65 °C for 60 min in the presence of a set of four specific primers recognized six distinct sequences of the GM cry1A gene. The rough detection limit to the GM cry1A in samples is as low as 0.01% (a weight ratio of transgenic insect-resistant rice/cotton to non-transgenic rice/cotton). Comparatively, the sensitivity of this LAMP method is 10 times over that of the conventional PCR method. Fifteen cultivars/events and five Bt strains with or without cry1A gene were analyzed using the LAMP method as well as PCR method. The results demonstrate that this LAMP method shows a distinct specificity to the GM cry1A gene comparing with PCR analysis. Therefore, this LAMP method will be a potential effective tool for screening the GM cry1A gene in GM crops which are widely plant in China and other developing countries.     

热轧带钢结疤缺陷产生原因及控制

针对某热轧带钢厂带钢表面结疤缺陷的外形特征及分布规律,分析了该缺陷产生的原因。通过对精轧侧导板开度余量及短行程数值设置固化、优化电气控制程序确保剪前导板线性化、精轧侧导板上安装压力传感器等措施,有效降低了结疤缺陷发生率。     

基于系统平衡的成都市耕地保有量预测

随着城市化进程的加大,耕地减少不可避免,耕地保有量预测为耕地保护提供依据。尝试以成都市2009年为基期,建立了3种人口预测模型,预测出成都市2015年和2020年人口规模。在综合分析四川省人口、粮食单产、复种指数、粮作比等因素的基础上,运用耕地需求量预测模型,预测出成都市基于粮食安全的耕地保有量水平。预测结果表明,人口的迁移增长已成为成都市人口增长的主要方式,2020年人口数量将达到13 069万人,耕地保有量为323 458 hm2,和2020年耕地面积的预测结果相差33 019 hm2。如果按现在的耕地占有速度,2020年将达不到预测的耕地保有面积。根据分析,应该进一步控制人口增长及加大耕地保护力度,提高粮食单产量。     

定向麦秸板制造工艺概述

阐述了生产定向麦秸板的意义,按生产工艺流程对每个工段进行了简要叙述,并对定向麦秸板生产的关键技术进行了讨论。