The Identification of QTL Associated with Cotton Fruit Branch Length Suitable for Mechanized Harvest Utilizing BSA-seq

[Objective] This study aims to identify quantitative trait loci (QTLs) associated with cotton fruit branch length by using the combination of bulked-segregant analysis (BSA) and next-generation sequencing (NGS) method. [Method] In this study, the cotton F₂ segregating population was developed with the short branch line Sujimian 125 and long-branch variety Sikang 1 as cross parents. According to the average internode length of fruit branches in middle, extreme individuals in F₂ population were divided into two groups to generate the bulked DNA samples. The whole-genome resequencing of two DNA bulks was applied to analyze the single nucleotide polymorphism (SNP) and insertion-deletion (InDel) between two groups, and the fruit branch internode length related QTLs were detected using Euclidean distance (ED). [Result] With SNP data obtained from sequencing, a 0.8 Mbp range associated region on chromosome A3 was identified; with InDel data obtained from sequencing, a 1.09 Mbp range associated region on chromosome A3 was identified. Two regions overlapped, and the overlapped range was 0.77 Mbp. [Conclusion] This result suggested that the difference between I-type fruit branch and zero-type was due to different genetic locus and pattern rather than dosage effect of the same gene.     

旱垂柳转录组测序及赤霉素在垂枝形成中的作用

垂枝作为特殊的林木形态结构,因形态优美在全世界被广泛用于绿化和园林景观而成为研究热点。国内外对垂枝植物的研究表明赤霉素在垂枝形成中起作用,但是垂枝形成的分子背景研究仍比较缺乏。本研究以旱垂柳(Salix matsudana var. pseudo-matsudana)的垂枝为研究对象,通过对旱垂柳在不同生长发育时期的叶片、茎尖和茎基部进行了转录组和数字表达谱测序研究,共获得71 474个Unigenes序列。将Unigenes与COG和KEEG数据库比对,与转录和信号转导机制相关的基因在旱垂柳中高度富集,最终确定8 359个差异表达的基因,其中427个基因与激素相关。进一步分析赤霉素相关基因得出,主要参与2条赤霉素合成途径,具有生物活性的GA4是合成途径中的主要产物,而且GA4在枝条中的含量显著高于GA1和GA3。参与赤霉素信号转导途径中的GID1B在旱垂柳中上调表达,以及在G1和G4生长期的表达量高于其他时期,而DELLA蛋白GAI在G2生长期以后下调表达,GID1B和GAI在旱垂柳的垂枝生长过程中可能起非常重要的作用。这些研究结果将有助于探索赤霉素在旱垂柳垂枝形成中的分子作用,可为林木形态的遗传改良提供基础理论依据。     

桑叶和桑枝综合利用概况

近年来,桑叶和桑枝的综合利用研究取得较大进展。桑树资源的开发利用,具有广泛的生态、经济和社会效益,对促进传统蚕桑产业的转型升级具有重要意义。桑叶富含多种保健和营养成分,桑叶茶和桑叶饲料开发已初具规模;桑枝资源丰富,成本低廉,桑枝食用菌栽培、桑枝地板、桑枝造纸以及桑枝制药原料已初见成效。     

四川桤木嫩枝扦插育苗技术研究

研究表明 :桤木扦插育苗 ,穗条带顶芽或带 1片叶可显著提高穗条生根率 ,扦插时间则以 5月中旬～ 6月中旬和 9月上旬扦插生根率最高 ,GGR生根剂不同浓度处理后的穗条 (采穗母树 2 .5a生 )其生根率没有显著差异     

微红梢斑螟危害枝梢的空间分布型及抽样技术研究初报

本文采用2种回归分析法和6种聚集指标，对微红梢斑螟危害梢在马尾松林中的分布进行了研究。结果为聚集分布，在此基础上，利用Iwao的方法进行了序贯抽样。     

油茶幼林结实与果枝特性研究

通过对油茶自花授粉全同胞子代、无性系间控制授粉全同胞子代、半同胞子代和无性系四种不同群体的结果枝特性和开花结实特点等主要经济性状的研究,揭示了四种群体及其优良林分的结实特性和产量规律,为油茶杂交组合、优良家系和无性系等良种的生产应用和栽培技术、以及进一步开展杂交和选择育种研究积累了必要的技术和理论知识。     

中间锦鸡儿硬枝扦插试验

以中间锦鸡儿为材料进行了硬枝扦插试验,在珍珠岩和粗沙2种不同的基质上进行扦插,分别采用不同浓度的吲哚丁酸(IBA)、奈乙酸(NAA)、ABT1#、ABT2#生根粉进行处理。试验表明:粗沙硬枝扦插较为理想,平均生根率较珍珠岩提高14.1%;不同激素种类对中间锦鸡儿硬枝插穗生根情况影响极显著,珍珠岩基质上扦插,以ABT1#100 ppm和200 ppm生根效果最佳;粗沙基质上扦插,处理浓度以IBA 1000 ppm、ABT1#500 ppm、ABT2#500 ppm对中间锦鸡儿硬枝扦插生根效果最佳。     

Application of the pipe model theory to non-destructive estimation of leaf biomass and leaf area of pruned agroforestry trees

The relationship of branch cross sectional area (CS) to leaf biomass (LM) and leaf area (LA) was studied in three agroforestry tree species,Calliandra calothyrsus Maissn.,Erythrina berteroana Urban andErythrina poeppigiana (Walpers) O.F. Cook, to develop a non-destructive method for the estimation of LM and LA for trees managed with periodic pruning. Variation in these relationships was observed according to the bifurcation level and, in theErythrina spp., by clone. All the relationships were linear except the CS-LM relation in small branches ofE. poeppigiana, where it was initially exponential. At main branch level the relationship of CS to LM and LA was linear in all cases but the regression parameter values varied between species and clones, with determination coefficient (R²) 0.88–0.99. It was concluded that the ratio of main branch CS to LM and LA can be used for non-destructive estimation of the latter variables. The method has the additional benefit that the regression parameter value reflects the allocation of dry matter within a tree and, consequently, may give indications about its possible uses in different agroforestry systems.Work carried out at the Centro Agronómico Tropical de Investigación y Enseñanza (CATIE), Turrialba, Costa Rica.     

几种植物生长调节剂对澳洲坚果幼树的控梢效果比较

用植物生长调节剂多效唑、乙烯利、矮壮素、B9对澳洲坚果幼树进行控梢处理,结果表明:多效唑对澳洲坚果幼树的生长有极显著的抑制作用,其中3和2.5g/L处理的幼树营养生长受到严重抑制;乙烯利对澳洲坚果幼树新梢的抽发、梢长、节间长有显著影响,1.5和2g/L处理后幼树的新梢表现出乙烯的"三重效应"。矮壮素和B9对澳洲坚果幼树新梢抽发抑制作用极显著,矮壮素1.5、2g/L处理的幼树在喷药后2个月没有抽发新梢;B9处理的幼树新梢抽发量很少,对照的新梢数是其它处理新梢数的数十倍。     

小型枝桠削片机的结构分析

小型枝桠削片机主要用于伐区加工直径为60～80 mm的枝桠,要求其体积小、结构简单、移动方便和易于操纵,因此在结构设计上有其特殊性.在分析其结构特点的基础上,找出影响木片加工质量的因素,提出改进建议,以利于产品的设计和改进.