透视极端育种:基因组学在农作物改良中的充分应用

在过去的10年中,基因组学的变革使我们大大加深了对植物生物学的理解,尤其是对模型植物,如拟南芥。同基因组学变革相关的技术,如定向诱导基因组局部突变(TILLING)、基因芯片定位及结合映射,在不远的将来也会被广泛应用于农作物的改良。通过此类研究所获得的决定所期望性状的基因可通过标记辅助育种而加速渗入优良种质。     

In field non-invasive sensing of the nitrogen status in hybrid bermudagrass (Cynodon dactylon × C. transvaalensis Burtt Davy) by a fluorescence-based method

The level of N fertilization and the content of leaf N in Cynodon dactylon × C. transvaalensis Burtt Davy cv. ‘Tifway 419’ bermudagrass were evaluated non-destructively with a fluorescence-based method. It was applied directly into the field by using the Multiplex portable fluorimeter during two consecutive seasons (2010 and 2011). In the 2010 experiment, the nitrogen balance index (NBI₁) provided by the sensor was able to discriminate (at P < 0.05) six different N levels applied, up to 250 kg ha⁻¹, with a precision (root mean square error, RMSE) in the rate estimate of 3.29 kg ha⁻¹. In 2011, the index was insensitive to the N treatment between 150 kg ha⁻¹ and 250 kg ha⁻¹ N rates, and its precision was 39.98 kg ha⁻¹. Calibration of the sensor by using the destructive analysis of turf samplings showed a good linear regression between NBI₁ and the leaf N content for both 2010 (R² = 0.81) and 2011 (R² = 0.93) experiments. This allowed mapping of the leaf N spatial distribution acquired by the sensor in the field with a prediction error of 0.21%. Averaging the overall estimates of leaf N content per N treatment provided an upper limit of 200 kg ha⁻¹ for the required fertilization, corresponding to a critical level of leaf N of about 2.3%. Our results confirm the usefulness of the new fluorescence-based method and sensor for a precise management of fertilization in turfgrass.     

浅析甘肃TM遥感影像地图制作

卫星遥感影像数据较大,覆盖我省的TM遥感影像达到了15G以上的量级,给影像地图的制作带来一定困难。本文通过ENVI4.0软件,针对甘肃省TM卫星遥感影像地图的制图方法及相关技术问题进行了探讨。     

一份新的水稻斑点叶突变体spl32的鉴定和基因定位

从F2(粤晶丝苗2号/H4)群体中,鉴定出一份显性斑点叶突变体spl32(spotted leaf 32)。其叶片褐色斑点受自然光诱导,在幼穗分化期从叶尖逐渐扩散至叶鞘,台盼蓝染色表明斑点并非由细胞死亡引起。以从F5杂合个体分离出的正常叶色植株为对照,斑点叶植株的穗粒数、结实率显著降低。斑点出现后,spl32的POD活性和MDA含量均显著高于对照;同时,spl32叶片光合色素含量降低,但荧光动力学参数并无显著变化。抽穗期人工接菌表明,spl32对水稻白叶枯病菌抗性较对照显著提高。遗传分析表明spl32斑点性状由一个显性基因Spl32(t)控制,利用F2(02428/spl32)群体将其定位在第11染色体Ind-c和RM206之间,推测该基因为一个新的水稻斑点叶基因。     

玉米籽粒快脱水研究进展

玉米机械化生产尤其是机收是提高中国玉米综合生产能力、促进农民增收的重要措施,而玉米籽粒含水量是影响玉米机收尤其是粒收的主要因素。本文基于已发表的文献分析了玉米籽粒脱水速率的概念及其快脱水品种培育的重要性,归纳了快脱水玉米种质的挖掘、快脱水性状的遗传与基因定位以及快脱水性状的表型选择方面的研究进展,最后从加强玉米籽粒快脱水等机收性状遗传机制的研究,重视早熟、抗倒、抗病、快脱水等优异种质的挖掘和创制,同时重视育种材料的大田和室内的表型选择等三个方面对快脱水玉米育种进行了展望。     

应用RFLP图谱定位分析籼稻粒形数量性状基因座位

 用二个籼型杂交组合的F#-2群体，构建了二张分别具有89和93个标记位点的RFLP图谱。在此基础上，应用方差分析法和区间作图法对控制籼稻粒形性状的QTLs进行定位。在特三矮2号/CB1128群体中，定位了14个QTLs，其中5个控制粒长，2个主效基因（分别位于第5、第7染色体）和2个微效基因控制粒宽，1个主效基因和4个微效基因控制粒厚。在外引2号/CB1128群体中，共定位了13个QTLs，其中5个影响粒长，2个主效基因（分别位于第2、第5染色体）和3个微效基因控制粒宽，3个微效基因影响粒厚。此外，估算了每个QTL的贡献率、加性效应和显性效应值，分析某些染色体区间的多效现象，比较分析二群体QTLs定位结果的异同。     

Stock evaluation of giant scallop (Placopecten magellanicus) using high-resolution acoustics for seabed mapping

Survey designs in use for the evaluation of sea scallop stocks do not consider the variability of sediment type, despite strong evidence of its importance for the recruitment and survival of scallops on the sea floor. This study examines the distribution of scallops on Browns Bank, Scotian Shelf, at two test sites, in comparison to sea floor sediment distribution, with particular attention to the effects of small-scale sediment variability on the abundance of the commercially exploited scallop. Important links between scallop abundance, sediment type and habitat structure are described. Scallops are strongly associated with gravel lag deposits, which are readily distinguishable from sand-covered terrain through the use of multibeam backscatter data. There exists a highly significant correlation between scallop survey catch rates and backscatter intensity which can be used for the prediction of scallop stock abundance. Developments in underwater acoustics enable for more precise sea floor mapping and contribute to better estimates of scallop abundance.     

红树林遥感成图研究综述

介绍和评述了当前国际上红树林遥感成图的主要方法，地理信息系统、全球定位系统在红树林遥感成图中的应用，对其发展趋势进行了分析。     

DASM系统在云南新松叶峰虫灾航空调查中的应用

介绍了美国林务局广泛使用的航空快速勾绘系统DASM,阐述了其采集模板的数据库结构、工作底图制作与导入、采集界面设置以及数据后处理问题.并以“小松鼠”直升机为搭载平台,在云南省大理巍山县林区进行了不同悬停高度(100,200,400 m)下的祥云新松叶峰虫灾面积勾绘作业,验证了系统主要关键技术在我国西南林区的适应情况,探讨了提高系统精度的几种可能途径.结果表明,该系统可以满足林业病虫害的发生位置、致病面积快速调查的需要;同时,直升机悬停高度控制在200 m以下更易于实现勾绘的精确性.     

Analysis of diversity and distribution of <Emphasis Type="Italic">Jatropha curcas</Emphasis> L. germplasm using Geographic Information System (DIVA-GIS)

Jatropha curcas L., an important biodiesel plant, has been studied for its distribution and diversity in south east coastal zone of India using DIVA-GIS. The Grid maps were generated on the distribution pattern, plant height, number of primary branches, collar length, number of fruits per cluster and oil content. Flowering in the collected accessions were grouped in to very early (35%), early (29%), medium duration (10%), late (20%), and very late (6%) types. Analysis for richness using rarefaction method of DIVA-GIS showed that Ranga Reddy district of Andhra Pradesh is the potential area for germplasm with high oil content. The present study revealed that diverse germplasm accessions of J. curcas are distributed all over the south east coastal zone and enabled us to find out gaps in collection and diversity richness from SEC zone of India for conservation.