Chromosomes responsible for sensitivity of embryo to abscisic acid and dormancy in wheat

The sensitivity of the embryo to abscisic acid (ABA) has been reported toplay an important role in seed dormancy. Using ditelocentric lines of wheatcv. Chinese Spring (CS, nondormant and ABA insensitive), F₂ seedsbetween monosomic lines of CS and a wheat line Kitakei-1354 (dormant,ABA sensitive) and deletion lines of CS chromosome 4A, germinability ofseeds and embryo-half seeds incubated in water and ABA were examined. The results indicated that the long arm of chromosome 4A carried majorgene(s) for the embryo sensitivity to ABA and dormancy. Chromosome2D might be also involved in the sensitivity to ABA.     

近51年呼伦贝尔市暴雨日数的时空分布特征

为了研究呼伦贝尔市暴雨日数的时空分布特征,防范暴雨引发的洪涝灾害对农业产生的影响,利用呼伦贝尔市地区16个气象站1960—2010年逐日降水资料,采用线性趋势分析和Mann-Kendall突变检验方法,分析呼伦贝尔市近51年暴雨日数的时空分布。结果表明：该地区暴雨日数具有明显的年代际变化,总体方向呈减少趋势;暴雨的发生具有明显的季节分布特征,暴雨开始于春季5月,结束于秋季9月,且主要出现在夏季,并且集中在7月末和8月初;暴雨空间分布具有明显的地域性,各站暴雨日数和暴雨雨量极值均出现在松嫩平原与大兴安岭山脉东南过渡的山坡上,说明呼伦贝尔市暴雨受地形影响明显;暴雨日数突变减少时刻发生在1997年,突变后暴雨日数减少趋势显著。     

Soybean plant height QTL mapping and meta‐analysis for mining candidate genes

Plant height is closely related to seed yield of soybean. The goal of this study was to identify important loci affecting soybean plant height using meta‐analysis based on a reference physical map. Plant height related to QTLs was mapped across eight years with a RIL population by WinQTLCart v2.5. 182 QTLs related to plant height of soybean from database and our research were collected, and each QTL was projected onto the soybean physical map by software BioMercator v2.1. The confidence interval of meta‐QTL ranged from 0.09 to 5.07 Mb, and the mean phenotypic variance ranged from 4.9% to 73.0%. Furthermore, 4,259 candidate genes were located in these consensus QTLs, and 40 of them were involved in the plant growth and stem elongation and annotated as plant hormone signal transduction (pathway ID ko04075) in KEGG pathway. These results would lay a foundation for fine mapping of QTLs/genes related to plant height and marker‐assisted selection for breeding in soybean.     

河南农村生态环境保护与建设研究

农村的生态环境问题不容忽视。长期以来,由于工农业污染,经济发展的压力和自然环境的恶化等原因,使农村生态环境问题十分突出,已成为社会经济可持续发展的严重制约因素。为了创造一个有利于实现农村经济社会可持续发展的良好生态环境,笔者就人口大省河南为例,对农村生态环境保护与建设提出一些新的看法。     

濒危东乡野生稻遗传多样性及其生态保护学研究进展

东乡野生稻蕴含大量优异性状和有利基因,是栽培稻遗传改良重要的种质资源。然而“东野”正面临着急剧减少甚至是灭绝的威胁,为此评价并保护现存“东野”的遗传多样性刻不容缓。同时“东野”的多样性研究对解析其遗传进化机理以及在水稻育种上的利用有着重要意义。为此,综述了近年来不同保存方式、不同年份、不同世代以及与其他生态类型野生稻和栽培稻等多个角度有关“东野”遗传多样性及其保护研究成果。通过对存在的相关问题分析,笔者认为应该建立科学统一的遗传多样性评价体系,并提出了“东野”遗传多样性研究前景和生态保护建议。     

不同茶树良种加工祁红香螺的品质比较研究

本试验以祁门槠叶种为对照,选取安徽1号、安徽3号和凫早2号三个国家级无性良种为试验对象,按照相同采制标准制成祁红香螺茶样,通过对主要生化成分测定结果和感官审评的比较,研究不同茶树品种对祁红香螺品质的影响。结果表明：三个无性良种茶样的内含物质丰富,生化成分比例协调;形美质优,感观审评五项因子的综合评分皆高于对照,得分从高到低依次为凫早2号、安徽3号、安徽1号、祁门槠叶种,说明三个国家级无性茶树良种均可作为生产祁红香螺的选用品种,尤其以凫早2号、安徽3号为宜。     

论中国种业准入门槛的提高

由农业部牵头起草的<关于加快推进种业改革发展的指导意见>已处于征求意见阶段,并将于近期对外发布经过重新修订的<农作物种子生产经营许可证管理办法>,虽然这两个文件还未正式发布,但部分省份的种子总站已经在执行这些文件的部分条文,受其影响,部分企业的生产许可证年审无法过关,影响了企业的生产经营.这两个文件是在什么情况下提出的?和旧的政策有什么不同?新政出台后种子企业如何应对?这些都是业内人士不得不思考的问题.     

不同种植方式对超级稻籽粒灌浆特性的影响

为探明不同种植方式下高产水稻的籽粒灌浆特性,以超级稻品种淮稻9号和III优98为材料,应用Richards方程W=A/(1+Be^–Kt)^1/N对旱育中苗壮秧精量手栽、小苗机插、直播3种种植方式水稻强、弱势粒的灌浆过程进行了比较研究。结果表明,(1)不同种植方式下,超级稻产量差异极显著,手栽最高,机插次之,直播最低。与手栽和机插相比,直播的千粒重和结实率显著降低,而手栽和机插之间千粒重和结实率的变化因品种类型而异。(2)不同种植方式下超级稻强、弱势粒灌浆特征为明显的异步灌浆型。强势粒达到最大灌浆速率的时间(T_max)早,最大灌浆速率(GR_max)、平均灌浆速率(GR_mean)以及终极生长量(A)和起始生长势(R₀)均明显大于弱势粒,而活跃灌浆期(D)和有效灌浆时间(T₉₉)明显小于弱势粒。(3)与手栽和机插相比,直播强势粒的GR_max和GR_mean显著降低,T_max明显延迟,D、T₉₉显著增加。弱势粒的GR_max和GR_mean机插最大,手栽略小于直播,T_max直播最早,机插次之,手栽最迟,D、T₉₉手栽、机插、直播依次减少。(4)籽粒灌浆阶段特征方面,平均灌浆速率和贡献率均以中期最大,中期的贡献率强势粒和弱势粒分别达到60.53%和50.78%,不同种植方式间前、中、后各期在灌浆持续天数、平均灌浆速率和贡献率上的差异因粒位不同而异。(5)千粒重与强、弱势粒的GR_max、GR_mean和D呈正相关,且与弱势粒的灌浆速率(GR_max和GR_mean)显著相关,结实率与强、弱势粒的灌浆参数除强势粒的D外,均不显著相关。说明不同种植方式对超级稻的籽粒灌浆特性有明显影响,虽均为异步灌浆型,但其强、弱势粒的最大灌浆速率及到达最大灌浆速率的时间等灌浆特征参数均差异较大,在保持籽粒最终生长量和结实率稳定的条件下,提高籽粒的灌浆速率,特别是弱势粒的灌浆速率,对提高千粒重有重要的作用。     

起垄覆膜与土壤脱盐剂对江苏沿海中重度盐碱地棉花成苗和产量的影响

以中棉所79为材料,于2012和2013年在江苏大丰稻麦原种场盐碱地设计高垄覆膜、高垄不覆膜、土壤脱盐剂+覆膜、土壤脱盐剂+高垄覆膜、土壤脱盐剂+高垄不覆膜和平作覆膜6个处理对棉花出苗、产量及与抗盐相关的生理指标影响。结果表明:与平作覆膜相比(CK),高垄覆膜+土壤脱盐剂能显著提高籽棉产量和促进出苗,产量比对照提高32.00%~113.78%;土表20 cm土壤盐分降低最多,下降42.07%,出苗率提高148.8%。同时高垄覆膜+土壤脱盐剂处理能有效地减少棉苗叶片丙二醛和脯氨酸的积累,降低叶片超氧化物歧化酶(SOD)活力。因此,高垄覆膜与土壤脱盐剂的应用,由于能有效降低中重度盐碱地的盐分,从而有利于棉花发芽出苗,降低盐分逆境对棉苗的胁迫效应,最终促进产量提高。     

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.