The development of a genetic linkage map of blackcurrant (Ribes nigrum L.) and the identification of regions associated with key fruit quality and agronomic traits

The first genetic linkage map of blackcurrant (Ribes nigrum L.) was constructed using AFLP, SSR (genomic and EST-derived) and SNP markers, in a mapping population derived from two diverse breeding clones of blackcurrant from the SCRI breeding programme. Cluster analysis of the population revealed that the individuals within the population formed two distinct sub-populations, with segregation ratios consistent with one sub-population having the two intended parents, and the other being selfed segregants. The latter sub-population improves the map by providing a more informative estimate of recombination frequency than the crossed sub-population for some marker configurations, and also revealed the presence of two unlinked loci affecting viability. Several important phenological, agronomic and fruit quality traits were evaluated in the mapping population, and QTLs affecting these are located on the linkage map. This provides a framework for the development of marker-assisted breeding strategies for blackcurrant, to improve breeding efficiency and time to cultivar.     

Molecular characterization of the recombinant inbred line population derived from a japonica-indica rice cross

Recombinant inbred line (RIL) populations of rice are useful genetic sources for map-based cloning of agronomically important genes. Zhe733 is a high-yielding indica cultivar from China conferring resistance to rice blast (RB), rice water weevil (RWW) and straighthead; whereas Kaybonnet low-phytic acid 1-1 (KBNTlpa) is a mutant of a tropical japonica cultivar from the US containing low-phytic acid with average yield, and is susceptible to some RB races, RWW, and straighthead. A 355 RIL F₁₀₋₁₁ population derived from the cross of KBNTlpa × Zhe733 was recently released. Simple sequence repeat (SSR) markers were used to evaluate 269 RILs of this population. A total of 107 polymorphic markers were mapped on all rice chromosomes representing a total of 1,016.3 cM of genetic distance. Two hundred and thirty-five KBNTlpa × Zhe733 RILs (KZRILs) were clustered into seven groups based on allele frequencies of SSR markers. Twenty-three markers (21.1%) on chromosomes 3, 6, 7, 9, and 11 were found to favor Zhe733 (χ ² = 16.8−189.7 and P < 0.01) and five markers (4.6%) on chromosome 1 and 6 were found to favor KBNTlpa (χ ² = 18.5−46.6 and P < 0.01). Marker segregations were observed to be normal for both parents except 26 (10.2%) KZRILs were found to skew toward Zhe733 (χ ² > 15.7 and P < 0.01). Furthermore, the average frequencies of heterozygosity and non-parental alleles per KZRIL were 1.3% (0.0−38.9%) and 0.4% (0.0−15.0%), respectively. Thirteen heterozygous KZRILs were found at more than five markers loci and nine KZRILs were found with more than five non-parental alleles representing 5.1 and 3.5% of 255 KZRILs. Overall, this KZRIL population is a good population with relatively low frequencies of heterozygosity and non-parental alleles, and with relatively low percentages of skewed markers and skewed KZRILs. The profiles of these SSR markers should facilitate molecular tagging critical genes controlling yield, RB, RWW, and straighthead resistance.     

烤烟几种化学成分的QTL初步分析

以含137个株系的烤烟DH群体(G-28×NC2326)及其亲本为材料, 在以前作图数据的基础上, 新增23个标记。将这些标记数据合并起来构建了包括11个ISSR标记和158个RAPD标记、由27个连锁群组成的烤烟分子标记遗传连锁图, 覆盖长度2 094.6 cM, 相邻标记间的平均图距为15.95 cM。利用4个环境下的试验数据进行了总糖、烟碱、氧化钾3种烟叶化学成分的QTL初步分析, 共检测到7个加性效应QTL和9对加加上位性效应QTL, 其中3个加性QTL和3对上位性QTL存在QTL与环境互作效应(QE)。表明在烤烟总糖、烟碱、氧化钾的遗传控制中除加性效应外, 上位性效应也具有重要作用。对于烟碱、氧化钾检测到加性QTL与环境互作效应, 对于总糖、氧化钾检测到上位性QTL与环境互作效应, 利用这些与环境具有互作效应的QTL进行标记辅助选择时宜考虑特定的环境条件。     

“3S”技术及其在林业的应用现状与展望

本文介绍了"3S"技术的的内涵及特点,从森林资源调查、森林资源动态监测、林业专题图的绘制等方面分析了"3S"技术在林业中的应用现状,并对"3S"技术的发展趋势作了展望。     

应用MapInf0软件制作草地畜牧业各类专题统计地图的初步探讨

以青海省达日县建设乡为例,简要介绍了应用MapInfo软件制作草地畜牧业各类专题统计地图的主要过程和基本方法。     

鸡源和鸭源减蛋综合征病毒DNA酶切图谱分析

采用差速离心法纯化鸡源和鸭源减蛋综合征（ＥＤＳ）病毒,酚－氯仿抽提法提取两种毒株的核酸。选取ＥｃｏＲⅠ、ＢａｍＨⅠ、ＢｇｌⅠ、ＢｇｌⅡ、ＫｐｎⅠ、ＰｓｔⅠ和ＨｉｎｄⅢ７种限制性内切酶,对两种毒株进行酶切图谱比较。结果显示,鸡源株酶切片段数分别为４,４,６,８,５,９,１０,共计４６个片段;鸭源株产生的酶切片段数分别为４,４,５,７,９,１０,８,共计４７个片段。两者的酶切结果除ＥｃｏＲⅠ完全相同外,其余均存在不同程度的差异。由此表明,鸡源和鸭源ＥＤＳ病毒虽然血清型相同,但在基因水平上存在较大的差异,属不同基因型。     

Diversity among Turkish maize landraces based on protein band analyses and kernel biochemical properties

Maize (Zea mays L.) landraces are considered to be important genetic resources for improving maize. To use these sources effectively, the extent of genetic diversity among them needs to be determined. While maize landraces from different countries have been evaluated, there is only limited information available on Turkish maize landraces. Thus, our objective was to investigate the genetic relations among 35 different landraces, along with inbred lines B73 and Mo17, using the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We also measured seven kernel-quality traits, viz., protein content, oil content, zein content, lysine content, tryptophan content, and amylose/amylopectin content. Cluster analysis was performed to classify the Turkish maize landraces relative to protein-band variation. Results of protein-band analyses showed there was significant diversity among maize landraces. There was also considerable variation for the kernel-quality traits of the landraces. Kernel oil varied from 2.83% to 6.27%, protein from 6.67% to 11.34%, zein from 1.87% to 8.88%, tryptophan from 0.017% to 0.053%, lysine from 0.14% to 0.81%, amylose from 5.9% 37.6%, and amylopectin from 62.4% to 94.1% among the landraces. A total of 25 protein subunits, with molecular weight ranging from 10 to 110 kDa, were determined, and all of them, except for three bands, were polymorphic. Polymorphism information content (PIC) of the subunits ranged between 0.00 and 0.50. Maize landraces were classified into two main clusters; the first cluster included 18 landraces and inbred lines B73 and Mo17, whereas the second cluster comprised 17 maize landraces. Overall, results revealed that Turkish maize landraces having similar geographical origins were classified in the same clusters and exhibited a high level of diversity relative to protein subunits.     

基于CiteSpace的农业灌溉水资源价值知识图谱分析

基于2000—2021年WoS数据库收录的3 687条农业灌溉用水价值相关文献,利用CiteSpace软件绘制全球灌溉用水价值研究的知识图谱,分析国内外灌溉用水价值研究的发文量、作者、国家、期刊和机构分布情况、研究热点及发展趋势。研究结果表明：2000—2021年,灌溉用水价值领域发文量整体呈上升趋势;发文核心作者和团队主要来自中国和美国;研究力量主要分布在中国、美国、西班牙等国家;中国科学院、中国农业大学、德黑兰大学等机构贡献突出;灌溉水价和水资源的利用效率始终是研究的热点内容;从发展趋势看,灌溉用水价值的多维度评估以及灌溉用水价值的时空动态变化特征是未来研究关注的热点;多源时空数据源、结合计算机人工智能技术的多种定价方法的融合及优化成为灌溉用水价值研究的新趋势。     

Integration of geospatial and cattle nutrition information to estimate paddock grazing capacity in Northern US prairie

Spatiotemporal variability in forage quantity and quality requires that regular assessment is needed of the capacity for grasslands to support livestock nutritional requirements. Current methods for estimating grazing capacity are typically production-based and lack the forage quality data necessary to match nutrients in forage with livestock requirements in real time. This paper describes a method for estimating short-term grazing capacity for small (1–20 ha) paddocks using cattle nutrition and high spatial resolution forage data in Geographic Information Systems (GIS) for mixed-grass prairie. We define grazing capacity as the number of days a specific paddock will support the nutritional requirements of beef cattle. We integrate previously published methods for estimating cattle nutritional requirements, forage quality (crude protein) and forage quantity (phytomass) to estimate grazing capacity based on current standing-crop. The model utilizes high-resolution (<30-m) satellite imagery or field data to estimate short-term grazing capacity for small paddocks. Three versions of the model were evaluated on one paddock under cattle use in 2007. One version was parameterized using data collected on June 22 from the Landsat Thematic Mapper (TM), one version was parameterized using data collected June 23 from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), and one version was parameterized using data collected June 20 from field clippings. TM and ASTER versions underestimated grazing capacity by four days while the field version overestimated grazing capacity by one day. Results suggest integration of cattle nutrition and forage data in GIS could assist with stocking rate adjustments, but additional trials are needed.     

利用多种分子标记构建龙眼高密度分子遗传图谱

 以龙眼特优质品种‘凤梨朵’为母本, 大果型主栽品种‘大乌圆’为父本, 杂交创建了‘凤梨朵’ ב大乌圆’F₁群体。从该杂种群体中随机选用94个单株作为作图群体, 连同两个亲本品种, 进行了RAPD、ISSR、SRAP和AFLP分子标记分析, 并运用JoinMap3.0进行连锁分析, 分别构建了‘凤梨朵’和‘大乌圆’的分子遗传图谱, 其中, ‘凤梨朵’的遗传图谱为21个连锁群, 包含183个标记位点,覆盖总图距965.1 cM, 位点间平均遗传距离为5.84 cM; ‘大乌圆’的遗传图谱为22个连锁群, 包含251个标记位点, 覆盖总图距1 064.8 cM, 位点间平均遗传距离为4.65 cM。这是龙眼上首次报道的高密度分子遗传图谱, 为后续的基因定位及辅助选择奠定了良好的基础。