Some Agronomic Strategies for Organic Quinoa (Chenopodium quinoa Willd.)

Quinoa is a potential new seed crop for protein feed and human consumption in Europe, with tolerance to a range of abiotic stresses. For this purpose the study was planned to analyse the effect of important agronomic strategies like nitrogen level, N application strategy, row spacing and harvest time on yield and quality of quinoa. The experiments took place in the field of the experimental station of the Faculty of Science, University of Copenhagen. Three levels of organic nitrogen from slurry was used (60, 120 and 180 kg N ha^?1), supplied either all at once at sowing, or split between sowing and beginning of the reproductive phase. The effect of row spacing and harvest time was studied by harvesting seeds at seed maturity, which occurred 2–3 weeks prior to the mechanical harvest by threshing, and a couple of months after. Yield increased significantly (P ≤ 0.05) with an application up to 180 kg N ha^?1, reaching 2200 kg ha^?1. Increasing N also caused a significantly increased seed weight (up to 3.3 mg) and protein content (up to 17 %). N level did not affect number and amount of weeds. Split application with part of the N applied at bud formation did not have a significant effect on yield. Delayed harvest had a negative influence on seed weight, whereas protein content was stable after harvesting even a month after seed maturity. A late harvest significantly reduced seed germination, being reduced by 50 % after a 2‐month delay. A conclusion from this study is that both yield and protein content of seed can be manipulated by N level and application strategy. Harvest time is important for securing a high seed quality measured as seed germination, seed weight and protein content. A fast germination of quinoa is an important characteristic demonstrating that the crop has good possibilities for being well‐established in the field when free from weeds at the time of sowing. The choice of row spacing is important and depends on weed control method. Weed control strategy should be developed based on modern precision tools.     

QTL mapping for capsaicin and dihydrocapsaicin content in a population of Capsicum annuum ‘NB1’ × Capsicum chinense ‘Bhut Jolokia’

Capsaicinoids are pungent compounds used for industrial and medical purposes including food, medicine and cosmetics. The Indian local variety ‘Bhut Jolokia’ (Capsicum chinense Jacq.) is one of the world's hottest chilli peppers. It produces more than one million Scoville heat units (SHUs) in total capsaicinoids. In this study, our goal was to identify quantitative trait loci (QTLs) responsible for the high content of capsaicin and dihydrocapsaicin in ‘Bhut Jolokia’. Capsicum annuum ‘NB1’, a Korean pepper inbred line containing 14 000 SHUs, was used as a maternal line. An F₂ population derived by crossing between ‘NB1’ and ‘Bhut Jolokia’ was generated to map QTLs for capsaicinoids content. A total of 234 markers, including 201 HRM, 21 SSR, 2 CAPS and 10 gene‐based markers of the capsaicinoid synthesis pathway, were mapped. The final map covered a total distance of 1175.2 cM and contained 12 linkage groups corresponding to the basic chromosome number of chilli pepper. Capsaicin and dihydrocapsaicin content were analysed in 175 F₂ pepper fruits using the HPLC method. The maximum total capsaicinoids content was 1389 mg per 100g DW (dry weight), and the minimum content was 11 mg per 100g DW. Two QTLs (qcap3.1 and qcap6.1) for capsaicin content were identified on LG3 and LG6, and two QTLs (qhdc2.1 and qdhc2.2) for dihydrocapsaicin content were located on LG2. We did not detect QTLs for total capsaicinoids content. The QTL positions for capsaicin content were different from those for dihydrocapsaicin content. These results indicate that the complexity of selecting for more pungent chilli peppers must be considered in a chilli pepper breeding programme. The QTL‐linked markers identified here will be helpful to develop more pungent pepper varieties from ‘Bhut Jolokia’, a very hot pepper.     

QTL Mapping of Important Agronomic Traits on Chromosomes Showing Marker Segregation Distortion in Interspecific Backcross Cotton Populations

[Objective] The purpose of this study was to map QTLs for yield, maturity, and fiber quality traits of cotton interspecific hybrid populations and to mine favorable alleles from the cotton genome for QTL fine mapping, gene cloning, and molecular marker-assisted selection. [Method] Four BC₁F₁ populations, E(E3), E(3E), (E3)E, and (3E)E, were developed by crossing sea island cotton 3-79 ("3") and upland cotton 'Emian 22' ("E"), and with "Emian 22" as the recurrent parent. BC1F2 populations derived from BC1F1 populations were phenotyped to allow mapping of QTLs for yield-, maturity-, and fiber quality-related traits on chromosomes showing segregation distortion. [Result] A normal distribution test indicated that six fiber quality-related traits, except for the micronaire value in E (E3) and the short fiber ratio in all populations, followed a normal distribution pattern; in contrast, earliness-related traits were not normally distributed in all populations, which suggests that genotype-environment interactions have strong effects on maturity-related traits. Using composite interval mapping, 47 QTLs were detected on three chromosomes (2, 16, and 18): 15 in (E3)E, 13 in (3E)E, 12 in E(E3), and 7 in E(3E), with the phenotypic variation explained (PVE) ranging from 8.8%–30.9%. A total of 27 fiber-related QTLs were discovered, with the PVE ranging from 9.0%–30.9%. Five yield-related QTLs (PVE = 8.8%–17.4%) and 13 maturity-related QTLs (PVE = 9.4%–19.4%) were also identified. [Conclusion] Comparison analysis showed that most QTLs in our study were consistent with the MetaQTL, including QTLs for boll weight, fiber length, fiber length uniformity, lint percentage, and micronaire value on chromosome 2; QTLs for fiber length, fiber strength, and fiber length uniformity on chromosome 16; and QTLs for boll weight, date of boll opening, fiber length, fiber strength, fiber length uniformity, and micronaire value on chromosome 18. Several detected QTLs in our study were not found in the MetaQTL, such as QTLs for date of boll opening and lint percentage on chromosome 16 and a QTL for the date from seedling to flowering stages on chromosome 18. These newly identified QTLs may provide novel insights for cotton QTL analysis.     

SSCP Marker Development and Analysis of Candidate Restorer Gene Rf1 for Cotton Cytoplasmic Male Sterility

[Objective] Locating the cotton cytoplasmic male sterility (CMS) restorer gene Rf₁ is important for investigating restorer gene mechanisms and improving restorer lines. In our previous study, a gene cluster, with nine Pentatricopeptide repeat(PPR) genes and nine other genes, was found within the 160-kb Rf₁ target region in Scaffold 333. The objective here was to improve the density of Rf1-linked markers in the target region and determine the expression profiles of candidate genes. [Method] Using the sequences of the 18 genes, we designed 155 single-strand conformation polymorphism (SSCP) primers covering all of the gene sequences to identify the polymorphic SSCP markers between the fertile and sterile pools. Additionally, real-time polymerase chain reaction(PCR) was performed to analyze the expression profiles of eight candidate genes in the four developmental stages of buds of sterile, maintainer and restoring lines, respectively. [Result] In total, 15 polymorphic primers were identified. A genotype analysis of the F₂ population was conducted using the 15 primers and 3 other polymorphic simple sequence repeats (SSR) markers. The markers were distributed in a 4.8 cM range. In addition, owing to the influence of sterile cytoplasm or restorer genes, most of the genes showed different expression patterns in the four developmental stages of the three lines' buds. [Conclusion] SSCP markers tightly linked to Rf₁ were identified and the expression profiles of candidate genes were determined. This study provides a basis for the further fine mapping of restorer genes and for candidate gene screening.     

不同基因型燕麦萌发期耐盐碱性分析及其鉴定指标的筛选

为探究不同燕麦品种萌发期的盐碱胁迫耐性,筛选适宜于松嫩平原种植的燕麦品种,用NaHCO₃胁迫模拟松嫩平原盐碱环境,对49份来自国内外不同地区的主栽燕麦品种进行了研究。试验测定了150mmol/LNaHCO₃胁迫下燕麦种子的发芽率（GR）、发芽势（GP）、发芽指数（GI）、活力指数（VI）、胚根鲜重（RFW）、胚芽鲜重（GFW）、胚根干重（RDW）、胚芽干重（GDW）、胚根长（RL）和胚芽长（GL）10个生长指标,运用不同方法对其进行数据分析,进而评定不同燕麦品种的耐盐碱等级。结果表明：通过对各生长指标的耐盐碱系数进行主分量分析,得到GP、RFW、RL相互独立的3个综合指标,涵盖了全部数据92.182%的信息量;通过隶属函数分析和聚类分析将49份燕麦品种分为4类,其中蒙燕1号、SX3、晋燕9号为高度耐盐碱品种,T6、T13等5个品种为耐盐碱品种,坝莜12号、SX2等29个品种为中度耐盐碱品种,HLJ 1、白燕7号等12个品种为盐碱敏感品种;由逐步回归分析方法得到最优回归方程D=-0.09+0.447GP+1.018RFW+0.366RL（R ²=1.000）,可为快速筛选耐盐碱燕麦品种提供科学依据。     

野生大麦的抗旱性及其在大麦遗传改良中的应用

干旱是主要的非生物胁迫性灾害,极大地威胁到全球的粮食供应,是影响农业生产的最重要因素之一。因此,培育抗旱性植物是解决干旱危害和粮食危机的根本途径。野生大麦已经适应广泛的干旱环境并具有丰富的遗传多样性,它们的抗旱基因与抗旱相关数量性状位点(QTLs)已经确定,对改良大麦抗旱性有巨大的潜力。综述了野生大麦的抗旱性及其在大麦改良中的应用,并对大麦抗旱育种中存在的问题以及今后发展方向进行了展望。     

巴西橡胶树幼叶和成熟叶比较蛋白质组学初步研究

为研究不同发育时期橡胶树叶片的功能代谢及揭示天然橡胶胶乳的合成调控机制,本研究以巴西橡胶树古铜期幼嫩叶片（幼叶）和稳定期完全成熟叶片（成熟叶）为实验材料,提取蛋白并进行双向电泳分离,结果发现幼叶与成熟叶相比,蛋白表达图谱差异显著,鉴定出的已知蛋白中多数参与了碳代谢及蛋白的翻译后修饰功能。本研究建立了成熟的巴西橡胶树叶片比较蛋白质组学研究的技术体系,获得了高分辨率的叶片蛋白双向电泳参考图谱,鉴定出来的腈裂解酶A链,核酮糖1,5-二磷酸羧化酶和肌动蛋白等在幼叶和成熟叶片中的表达量不同,这些结果为进一步揭示天然橡胶合成调控机制提供了一定的技术支撑与实验数据,对天然橡胶合成机制的研究以及其它热带植物叶片的蛋白质组学研究具有一定的参考意义。     

大叶女贞抗寒性及冬季叶片丙二醛和可溶性糖含量的变化

为了探索冬季大叶女贞叶片丙二醛、可溶性糖含量的变化规律及其与植株抗寒性的关系,以不同树龄、不同抗寒性植株叶片为材料,于2011年11月上旬-2012年3月中旬的每1个节气内分别采样,测定叶片丙二醛及可溶性糖的含量,并在2012年4月初对每个采样树冬季受冻情况进行调查。结果表明：不同树龄及不同抗寒性的植株冬季叶片丙二醛及可溶性糖具有不同的变化曲线,低温胁迫下叶片丙二醛及可溶性糖含量出现上升趋势越早、上升幅度越大的植株,其抗寒性越差。丙二醛、可溶性糖反映出的抗寒性与植株实际的受冻情况基本一致,两者可作为植物抗寒性测定的生理指标。优树的抗寒性与普通树或受冻树的差异,是由于其在低温胁迫下的生理调节能力不同所致,这种生理调节能力和植株的遗传性有关,且随着树龄的增加有增强的趋势。     

两种低氧条件对赤拟谷盗不同虫态的抑制作用

研究了在28℃、75%RH的温湿度条件下,5%和2%低氧储藏条件对赤拟谷盗高龄幼虫、蛹和成虫的抑制作用。在5%和2%氧气条件下暴露15d后,赤拟谷盗高龄幼虫化蛹率分别为95.0%和3.7%,蛹羽化率分别为98.0%和0%,成虫死亡率分别为12.7%和100%。本研究结果为气调储粮防治害虫提供依据。