新疆自育陆地棉品种SSR遗传多样性分析

利用SSR标记对94份新疆自育陆地棉品种的基因组进行分析,研究新疆陆地棉品种的遗传多样性。结果: 从分布于棉花全基因组的206对SSR标记中筛选出54对具有稳定多态性的引物, 共检测出153个多态性位点, 每对引物的等位变异为2~6个,平均为2.93个;基因型多样性(H′)变幅为0.0439–0.7149,平均为0.4491;引物多态信息含量(PIC)为0.0430–0.6640,平均为0.3831。表明SSR标记在品种间可以反映较丰富的遗传多样性信息。94份品种间成对遗传相似系数变幅为0.3846~0.9835, 71.9%的品种相似系数在0.601~0.800内,反映出新疆陆地棉品种间的遗传相似性相对较高。根据UPGMA 聚类分析,在阈值为0.63时,将94份品种划分为2个类群,说明新疆陆地棉品种间遗传关系相对简单,品种的遗传基础相对狭窄,品种遗传组分差异较小,总体上遗传多样性不够丰富;分子聚类结果与品种本身遗传系谱背景和演变趋势吻合度较高,符合品种的真实特性。研究证明,自育品种在分子水平上差异不大,需要努力拓宽品种选育的遗传基础。     

Estimation of Heat Tolerance Improvement in Recent American Pima Cotton Cultivars

Improving cotton ( Gossypium spp.) heat tolerance (ability to set bolls in high temperature environments) has been an important aspect of the American Pima (Pima) cotton ( G. barbadense L.) breeding program for over 25 years. However, heat tolerance is difficult to quantify. This report estimates change in heat tolerance of Pima cotton through yield response over 30 years in six Arizona counties that differ in elevation and mean summer temperatures. Pima cotton/upland cotton ( G. hirsutum L.) lint yield percentages were compared for each county by regression with year of production. County mean yield percentages were also compared with elevations. Pima cotton yields as percentages of upland cotton yields increased in five of the six counties over the 30-year period. Pima lint yield increased from 57 % of upland yield in 1956 to 75 % in 1985 when averaged over the six counties. This increase represents an estimated 206 kg lint ha-1 in addition to any upland yield increase. Comparison of regression coefficients suggest that nearly 50 % of the 30-year lint yield increase of Pima cotton at lower elevations was the result of increased tolerance to high temperature in improved cultivars. County 30-year mean Pima cotton lint yields as percentage of upland cotton yield increased significantly (P < 0.001) from 52.2% to 82.1 % as county elevations increased from 37 m to 1273 m (cooler summer temperatures). These results support reports of greater heat tolerance for upland cotton than Pima cotton, but also show that the difference between species has been reduced substantially by breeding in the last 30 years.     

Creation of a New Resistant Germplasm to Verticillium Wilt by Distant Hybridization in Upland Cotton

To create new germplasm lines resistant to Verticillium wilt in upland cotton, 65 distant hybridization germplasm lines (DHGLs) in upland cotton genetic background were cultivated by interspecific hybridization between Gossypium hirsutum and wild species including G. anomalum, G. armourianum, G. aridum, G. raimondii, G. mustelinum, interspecific F₁ backcrossing with G. hirsutum for four generations, and selfing for four generations, followed by a conventional breeding program. The results of agronomic trait identification during 2011-2012 indicated that average plant heights of DHGLs were closely similar to commercial cultivars of upland cotton, while average fruit branches, fruit nodes, bolls of DHGLs individual plant were lower than those in commercial cultivars of upland cotton. Average single boll weight and lint percentage of DHGLs were lower than commercial cultivars of upland cotton. Fiber length, strength, fineness and maturity of DHGLs were reasonably collocated. Fiber of most lines was suitable for spinning extra high count yarn, but the main fiber quality indices of commercial cultivars of upland cotton were not well coordinated. Identification of resistance to Verticillium wilt in defoliation disease nursery during 2012-2013 indicated that five DHGLs resistant to Verticillium wilt . Suyuan 040, Suyuan 045 and Suyuan 061 were highly resistant to Verticillium wilt with a disease index of 8.33, 4.35 and 7.79, respectively. Suyuan 030 and Suyuan 034 were resistant to Verticillium wilt with a disease index of 12.35 and 13.70, respectively. The genetic relationship of new germplasm lines resistant to Verticillium wilt were traced and showed that Suyuan 040 and Suyuan 045 were DHGLs of G. raimondii, Suyuan 061 was DHGL of G.mustelinum, Suyuan 030 and Suyuan 034 were DHGLs of G. aridum.     

Genetic variation and selection within glandless cotton germplasm

There is a renewed interest in research and use of glandless (free of gossypol) Upland cotton (Gossypium hirsutum L.) that can produce edible seeds for human food and animal feed. However, there was a lack of information on yield potential of existing glandless germplasm since intermittent breeding activities for glandless cotton were stopped in the U.S. before 2000. The objectives of the present study were to test obsolete and exotic glandless germplasm for possible production and evaluate progress in direct pedigree selection within the existing glandless germplasm in eight field tests. In multiple tests, the glandless cotton Acala GLS yielded only 65–80 % lint of the glanded control Acala 1517-08 and 46–75 % lint of commercial transgenic cultivars. Most of obsolete glandless germplasm and their selections yielded <70 % of Acala 1517-08 and only three selections yielded 82–89 % of the control. Genetic variation in yield and fiber quality traits was seen from significant differences between selections within the same glandless germplasm, indicating the existence of residual genetic variation. Most importantly, three selections from exotic glandless germplasm out-yielded Acala 1517-08 by 4–9 %, one of which had desirable fiber quality traits. These promising glandless lines with comparable yields to commercial cotton make it possible to revitalize the glandless cotton industry. More field tests will be needed to evaluate their yield potential and adaptability in the U.S. Cotton Belt.     

陆地棉×瑟伯氏棉杂种后代主要经济性状的遗传分析

用G.hirsutum作母本,G.thurberi作父本进行种间杂交,经染色体加倍获得可育杂种.对杂种后代8个经济性状的遗传变异规律进行了分析,绒长、籽指的变异系数较小,遗传力较高,分别为62.39%和51.02%,早期世代即可进行单株选择,遗传力较低的其它性状,早期时代以混合选择为宜,单株选择在后期世代才有效.在开放授粉的条件下,除单纤维强度外,各有益性状值均随世代数的递增而有不同程度的增加,用陆地棉连续回交,各种经济性状在后代中恢复得更快.连续自交不利于各种有益特征特性的累积和加强.     

利用多种质资源选育多抗型棉花品种的育种学启示

用选自陆海杂交后代的抗蚜选系抗７７为母本与具中棉亲缘的丰产品种江苏棉１号杂交，后代与父本江苏棉１号回交２次，经２０代综合鉴定和多性状定向选育的川棉１０９。该品种抗棉蚜，抗枯萎病和立枯病，耐黄萎病，耐旱，抗倒，耐瘠薄；并克服了陆地棉密茸毛与短纤维的连锁，将抗虫与抗病、丰产与优质有机组合；综合性状鉴定为国内领先和国际先进水平．目前己累积推广２７万ｈｍ２，是利用多质资源培育多抗型丰产品种的实例。多质资源是前提，多抗性、强生长势、强补偿力等构成了川棉１０９丰产稳产的综合遣传优势。启示育种目标日趋综合的现代棉花育种应选择宽广的质源，培育多抗性取代单抗性，并以胁迫和非胁迫双重条件下的产量比较为核心，实现抗性与丰产性的统一。     

棉花抗黄萎病品种选育的轮回选择研究——基础群体的构建

利用我国发现并鉴定的陆地棉核雄性不育系—洞Ａ为工具,将国内外现有的十多个抗（耐）棉花黄萎病的品种（系）和种质系导入到二个轮回群体中,拓建了棉花抗黄萎病轮回选择基础群体。从而为同步提高棉花的产量、品质和抗病性打下基础。     

转基因抗虫陆地棉与优质品系杂交铃重、衣分的遗传及其F_1杂种优势分析

利用7个陆地棉抗虫常规品种(品系)为母本,5个优质不抗虫品系为父本,按NCII设计配制了35个组合,采用"加性-显性遗传模型"("A-D模型")对亲本及F1两年的铃重、衣分数据进行了分析。结果表明,铃重的遗传主要受到显性效应的控制,衣分主要受到加性效应的控制,显性效应对衣分也有重要影响。F1的铃重具有极显著的正向群体平均优势和正向超亲优势,而衣分则具有极显著的正向群体平均优势和负向群体超亲优势。铃重狭义遗传率为0,进行杂交育种时不宜在早代进行选择,但因其具有较高的杂种优势,可通过杂种优势利用途径提高棉花的铃重;衣分具有较高的狭义遗传率,适宜在早中世代选择。     

Combining ability estimates for yield and fibre quality traits in 4 × 13 line × tester crosses of Gossypium hirsutum

The aim of this study was to estimate the general combining ability of the parents and specific combining ability of hybrids considered for the development of high yielding and better quality cultivars. Seventeen genotypes and 52 F₁ hybrids obtained by crossing 4 lines and 13 testers in line × tester mating system during 2003 were sown in randomized complete block design in 2004. Line × Tester analysis revealed significant GCA and SCA effects for all the traits except fibre elongation. Preponderance of non-additive gene action was obtained for seed cotton yield per␣plant and majority of its component traits including fibre traits. Among the parents: PIL-8 for days to 50% flowering, CCH-526612 for boll weight, CITH-77 for number of open bolls per plant and CNH-36 for seed cotton yield per plant were detected with higher general combining ability. Parent, CCH-526612 for 2.5% span length, fibre strength and fibre elongation and AKH-9618 for micronaire value, fibre strength and fibre elongation were good combiners for fibre quality traits. The F₁s achieved high seed cotton yield by producing more number of open bolls. The high yielding hybrids with acceptable fibre quality traits were: CISV-24 × LH-1995, H-1242 × PIL-8 and RS-2283 × SGNR-2 deducted with significant SCA effects for seed cotton yield and fibre characteristics; 2.5% span length and fibre strength. These cross combinations involved at least one parent with high or average GCA effect for a particular trait.     

棉花抗红铃虫性对产量性状的影响研究

以不同抗性类型的陆地棉抗虫品种(系)和常规棉品种(系)作亲本配制杂交组合,将亲本和F1代杂交种共20个材料在网室、田间进行抗红铃虫鉴定和棉花抗红铃虫性对棉花产量的影响研究,试验表明,具有外源抗虫基因的抗虫棉皮棉产量高,稳产性好,尤其是抗虫杂交棉具有明显的杂种优势。相关分析结果,棉花种子虫害率与皮棉产量、子棉产量、单株成铃数和霜前花率呈极显著负相关;与衣分和僵瓣黄花率成极显著正相关;与单铃重相关性较低。结果表明,利用外源抗虫基因转导的棉花新材料作为杂交亲本,可以培育出丰产高抗棉花害虫的棉花新品种,尤其适合培育抗红铃虫的杂交棉品种。     

棉花抗草甘膦突变体筛选及其在杂种优势利用中的应用

采用体细胞连续定向筛选技术,结合体细胞诱变技术,获得非转基因抗草甘膦的棉花突变体—R1098。R1098植株抗除草剂性状稳定;霜前皮棉产量与苏棉12号相当,纤维品质优良,抗枯萎病、耐黄萎病,是一优异的棉花种质资源。遗传试验结果表明,R1098的抗草甘膦性由一对显性基因控制,无细胞质效应。用R1098作父本与一般陆地棉杂交,其F_1仍具有抗草甘膦特性,可以用于棉花杂交种的纯度鉴定和假杂种自动清除,有利于棉花杂种优势利用的进一步推广。     

陆地棉品种间杂种的霜前皮棉产量及其杂种优势研究

利用 2 0世纪八、九十年代我国棉花生产上推广的主要品种 (系 )做亲本 ,组配 15个组合的正反交杂种 ,对其 F1 、F2 代杂种的霜前皮棉产量及其竞争、中亲和超高亲优势进行了研究。结果表明 ,陆地棉品种间杂交 ,F1 、F2 代正交与反交组合间的霜前皮棉产量及其竞争、中亲和超高亲优势均无明显差异。 3 0个正反交 F1 杂交种具竞争、中亲和超高亲优势 (以下简称三优势 )组合率分别为73 %、10 0 %和 83 %。其中竞争优势在 15 %以上的组合率为 46.7% ,最大竞争优势值为 40 .6%。 3 0个正反交 F2 杂交种三优势组合率分别为 60 .0 %、90 .0 %和 66.8% ,其中竞争优势在 10 %以上的组合率达 3 3 .3 % ,最大竞争优势值仍达 3 1.3 % ,F2仍具有较高的生产利用潜能。亲本鲁 11、石远 3 2 1等品种 (系 )表现遗传配合力高 ,是目前棉花杂交制种选用的优良高产亲本。     

陆地棉品种与陆地棉族系种质系间杂种优势及其组成分析

采用ＮＣⅡ遗传交配设计,选用３个陆地棉常规品种和５个陆地棉族系种质系材料杂交,杂种Ｆ１代产量和纤维品质优势表现明显。通径分析结果表明,提高铃重,单株铃数的中亲优势,适当降低单铃种子数和株高的优势。在其它性状适宜的情况下,可以显著地提高皮棉产量的中亲优势。各个优势组合在产量优势来源上有差异。种质系材料在杂种优势利用上具有很大潜力。     

Dissection of genetic effects of quantitative trait loci (QTL) in transgenic cotton

When alien DNA inserts into the cotton genome in a multicopy manner, several quantitative trait loci (QTLs) in the cotton genome are disrupted; these are called dQTL in this study. A transgenic mutant line is near-isogenic to its recipient, which is divergent for the dQTL from the remaining QTLs. Therefore, a set of data from a transgenic QTL line mutated by Agrobacterium-mediated transformation (30074), its recipient and their F1 hybrids, and three elite lines were analyzed under a modified additive-dominance model with genotype × environment interactions in three different environments to separate the genetic effects due to dQTL from whole-genome effects. Our result showed that dQTL had significant additive effects on lint percentage, boll weight, and boll number per square meter, while it had little genetic association with fiber traits, seed cotton yield, and lint yield. The dQTL in 30074 significantly increased lint percentage and boll number, while significantly decreasing boll weight, having little effect on fibre traits, while those from the recipient and three elite lines showed significant genetic effects on lint percentage. In addition, the remaining QTL other than dQTL had significant additive effects on seed cotton yield, fruiting branch number, uniformity index, micronaire, and short fibre index, and significant dominance effects on seed cotton yield, lint yield, and boll number per square meter. The additive and dominance effects under homozygous and heterozygous conditions for each line are also predicted in this study.     

我国陆地棉品种的遗传多样性研究初报

选用１８个随机引物，对２１个陆地棉品种作ＲＡＰＤ分析，并对各品种的指纹图谱进行了聚类和相似性分析。结果表明大部分品种与其系谱吻合。研究结果充分展示了ＲＡＰＤ技术可以作为棉花品种分类和遗传多样性研究的可行方法。     

陆地棉核不育系杂交组合F1经济性状杂种优势及遗传分析

为探究利用陆地棉核不育系配制杂交种在经济性状方面的优势及遗传特点,采用3个陆地棉核不育亲本与4个陆地棉可育亲本不完全双列杂交设计,对12个F1杂交组合及对照经济性状进行表型方差分析,利用加性-显性（AD）模型,对其亲本及12个F1组合进行配合力分析,同时对经济性状进行遗传方差及相关性分析。结果表明,经济性状方面,F1组合竞争优势不明显。不育系2、可育亲本48784特殊配合力和一般配合力均较高,可选作优良杂交亲本;经济性状的加性方差占表型方差比值较大,单铃重、衣分的狭义遗传率在70%以上,早代选择有效;籽棉产量、皮棉产量、霜前皮棉产量的狭义遗传率在25%以上、显性方差占表现总方差的比值达到极显著水平,这3个性状宜在偏晚世代选择,并且有较好的杂种优势利用潜力;除衣分与籽棉产量加性遗传相关不显著、单铃重与衣分加性遗传负向极显著相关外,其他成对性状加性遗传相关均达到了正向显著水平以上;籽棉产量、皮棉产量、霜前皮棉产量之间及单铃重与衣分的显性相关都达到了极显著水平。不育系在棉花杂种优势利用方面具有较大的利用前景。     

陆地棉抗病虫性和一些重要经济性状之间的相互影响

1996～1998年,分别在自然病圃、人工病圃、网室和温室对19份陆地棉品系的抗病虫性和经济性状进行了全面鉴定。结果表明,这些陆地棉品系对不同病虫害的抗性相互之间存在高度正相关。其抗性、产量和品质主要指标之间也存在密切的正向或负向相关关系。在育种中如能协调好这些重要性状的相互关系,就能培育出高产、优质和兼抗病虫的棉花新品种。     

河北省棉花产量灰色理论分析与预测

为了解河北省棉花产量变化的规律,明确今后育种工作的目标和前景,利用灰色系统理论的GM (1,1)模型,依据1980~2003年河北省审定的棉花品种的区域试验产量,建立预测模型为: ^X(1)(k+1) ＝38965.718385e 0.024221－37990.718385。并在生产因素保持相对稳定的条件下,据此模型对河北省棉花生产进行规划性预测,为生产的规划与决策提供科学信息。明确棉花育种的总体目标是优化品种和品质结构,保持适纺中支纱品种选育的优势,重视发展目前市场短缺的长绒和中短绒陆地棉新品种选育。     

Cassava (Manihot esculenta Crantz) Growth Indices, Root Yield and its Components in Upland and Inland Valley Ecologies of Sierra Leone

Cassava is predominantly an upland crop that is also cultivated in inland valley swamps (IVS). Identifying physiological traits that can withstand excess moisture stress can aid in the selection and use of stable cassava cultivars in IVS. Three cassava cultivars were evaluated for growth and yield in the upland and IVS ecologies in the 1993–94 crop seasons using a randomized complete block design. In the upland, 80/40 outyielded 87/29 and 'coco', while in the IVS, 87/29 had the highest yield. Highest yielding cultivars in each ecology also had the highest tuberous root bulking rate (TBR), dry matter (DM) production, crop growth rate (CGR), relative growth rate, net assimilation rate (NAR), leaf area index, leaf production rate and leaf life. Positive correlations between these parameters and tuberous root yield were noted. High yield of 87/29 in IVS was partly due to its low tuberous root rotting. High root rotting in 80/40 was partly as a result of the greater depth of tuberous roots in the soil (0.3–0.6 m) as compared to the other cultivars (0.15–0.3 m) where roots were in contact with stressful water levels earlier than others. The yield and yield components, growth and leaf characters were all drastically reduced when the cultivars were grown in IVS as compared to upland. For example, root yields of 'coco', 87/29 and 80/40 were reduced by 53 %, 60 % and 92 %, respectively, in IVS. Selection of cassava cultivars with longer leaf life and leaf area maintenance leading to high CGR, TBR, NAR and harvest index (in IVS and upland), coupled with a shallow tuberous root formation zone (in IVS) can give higher root and leaf yields in the two ecologies.     

陆地棉种质资源抗旱性状的关联分析

干旱是导致全世界棉花严重减产、纤维品质下降的重要因素,因此获得高产、优质、耐旱的棉花新品种一直是棉花的育种目标。本研究选取217份陆地棉栽培种组成的自然群体为研究对象,采用全生育期处理组灌水量为对照组50%的干旱胁迫处理,并在处理后期对217份材料的株高、衣分、单铃重等18个性状进行2年2点的表型鉴定,干旱胁迫后,群体间响应差异明显,多个表型性状在对照和处理间表现显著差异。通过BLUP分析表型数据并计算各性状的抗旱系数;全基因组范围选取的214对多态性SSR分子标记扫描群体,共检测到393个多态性位点,基因多样性系数平均值为0.402,范围为0.072~0.631,PIC值平均为0.329,范围为0.070~0.560;群体结构分析表明,该群体可分为2个亚群。用上述SSR标记分别对18个性状的抗旱系数进行关联分析,共关联到76个极显著位点(P<0.01),表型变异解释率为2.930%~7.218%,其中共有14个标记位点能同时被2种或以上性状检测到。研究结果可为后期棉花杂交育种亲本选择及抗旱分子标记辅助育种提供理论基础及参考依据。