Diallel cross analysis of seed germination traits in sugar beet

A diallel cross design, involving six diploid O-type lines and their cytoplasmic male sterile (CMS) equivalents was used to examine the genetic control of characters determining seed viability and vigor of seed and seedling in sugar beet. Six characters including percentage of germination, seedling establishment, weight of 1000 germs, seedling vigor, speed of germination, and monogermity were analyzed. Additive genetic effects were shown to be highly important for all characters and significant dominance effects were found for the percentage of germination and seedling establishment, weight of 1000 germs, and rate of monogerm seeds produced by multigerm plants. There were significant reciprocal variations for most characters, indicating that maternal effects and differences of self-incompatibility mechanisms may influence the expression of some characteristics related to the amount of viable seeds produced in plant. Variance of genotypes for seedling vigor and speed of germination was nonsignificant, indicating that both characters are mainly affected by environmental factors. The relative importance of heritability estimates and the ratio of GCA, SCA, and environmental variances to phenotypic variances were calculated for all the traits examined. It is suggested that seed traits are as important as root quality traits for the development of sugar beet varieties. This revised version was published online in August 2006 with corrections to the Cover Date.     

重茬对甜菜品质的影响研究

为明确甜菜重茬的危害,利用多粒、单粒两种类型供试材料,在田间同时进行重茬和生茬比较试验。研究重茬对甜菜产量、品质质量的影响。结果表明：（1）供试的几个多粒种平均减产22429 kg/hm²,单粒种平均减产18354 kg/hm²。（2）多粒种平均含糖下降2.58度,单粒种下降1.36度。（3）K、Na、α-N,多粒种平均分别增加了0.37 mmol/100g、3.31 mmol/100g、1.04 mmol/100g,单粒种分别为0.15 mmol/100g、2.21 mmol/100g、0.39 mmol/100g。（4）重茬地甜菜有害物质含量增加导致甜菜的品质下降,糖份损失率增加,多粒种平均增加0.69,单粒种平均增加0.47;可提取糖率减少,多粒种平均下降3.27,单粒种平均下降2.17;产糖量减少,多粒种减少4996 kg/hm²,单粒种减少3814 kg/hm²。（5）重茬地褐斑病发病早,比生茬地高1~2级。     

利用SRAP与SSR标记分析不同类型甜菜的遗传多样性

为选育优质甜菜新品种, 指导种质资源引进和利用, 为进行分子标记辅助选择育种提供科学依据, 采用SRAP和SSR两种分子标记方法相结合, 对甜菜单胚雄性不育系及保持系等49份材料进行遗传多样性分析。利用4个表型差异显著的甜菜品系对SRAP的64对引物组合及SSR的11对引物组合进行扩增, 分别筛选出有效引物组合11对和9对。SRAP的11对引物组合共产生199条扩增带, 其中有86条多态性带, 多态性带的比率平均为43.7%。SSR的9对引物共产生35条扩增带, 多态性比率为100%。全部材料的平均遗传距离为0.3860, 平均遗传相似系数为0.6795, 大约30%的材料遗传距离或遗传相似系数具显著或极显著差异。遗传相似系数平均值比较, 多胚四倍体品系0.7264＞单胚杂交组合0.7243＞国外品种0.7060＞多胚二倍体品系0.6908＞单胚品系0.6837。在遗传距离0.20处, 将49个甜菜材料划分为A、B、C、D 4个类群, D类群又分为4个亚类, 较好地显示了甜菜材料丰富的遗传多样性。表明不同甜菜品种具有相当高的异质性, 国外与国内材料的遗传基础存在一定差异, 但生产应用的甜菜品种间存在亲缘关系较近、遗传基础较窄的倾向。     

甜菜下胚轴颜色选择对后代品系及杂交组合的影响

为探讨甜菜幼苗下胚轴颜色与其他诸性状的相关关系,于1988—2003年对若干甜菜四倍体及二倍体多胚品系进行了4~6代幼苗下胚轴颜色的分离纯化选择、品系与原亲本比较、以红绿胚轴品系为亲本配制正反交组合等系列鉴定试验。结果表明,该选择方法对二倍体品系效果不明显,而四倍体后代品系与下胚轴颜色的联应F值达5%显著水平,红绿胚轴品系间的产、质量差异较大、互有高低,根产量相差20%以上,含糖率相差1%以上。绿胚轴品系含糖率大多数高于红胚轴品系,绿胚轴品系K、Na含量低于红胚轴品系,且大多达到1%或5%显著水准,而有害性氮含量则相反;红胚轴品系的株高、叶长、叶宽大于绿胚轴品系。利用四倍体和二倍体的红绿胚轴品系为亲本相互配制的杂交组合其产、质量存在显著差异。甜菜幼苗下胚轴颜色选择可以作为创新甜菜种质与品种选育的新方法,将下胚轴颜色作为品种的标记性状也很适用。     

甲醇老化处理对甜菜种子发芽的影响

为了研究甲醇溶液人工老化处理对甜菜种子发芽指标的影响,探究甜菜种子的耐储性和老化机理,为甜菜种子的人工老化研究提供理论依据。本研究以2020年新收获甜菜种TX2020单粒种为实验材料,设置6个不同时间的老化时间(5、10、15、20、25、30 min),用甲醇老化法处理种子,通过对甜菜种子进行发芽试验,测定它们的发芽势、发芽率、发芽指数、活力指数、胚根胚轴总长以及种子浸出液电导率。结果显示,种子经过老化处理后各发芽指标均有所下降,与对照相比,种子的发芽势、发芽率、发芽指数、活力指数、胚根胚轴总长分别下降了8.8%～31.41%、13.96%～34.23%、2.66%～22.44%、16.63%～36.44%、7.54%～23.06%,而种子的浸出液电导率则出现上升的情况,较对照上升了34.73%～76.19%。研究结果表明,甲醇溶液能够抑制甜菜种子的萌发,随着时间的不同,甲醇溶液处理甜菜种子在发芽指标上的抑制效果也不同。     

不同甜菜单胚细胞质雄性不育系与保持系的遗传多样性分析

利用35对SSR引物分析40对不同的甜菜单胚细胞质雄性不育系与保持系的遗传多样性。结果表明：每对引物扩增得到的条带数在2～12之间,有效等位基因数(Ne)、Shannon’s信息指数(I)、Nei’s基因多样性指数(H)的平均值分别为2.306、0.891和0.519。采用类平均法(UPGMA)进行聚类分析并计算遗传距离。聚类结果显示,除供试材料22与其他材料的遗传距离较大,亲缘关系较远,单独为一类群;其余的供试甜菜品系可分为4个类群;共有14对甜菜单胚细胞质雄性不育系与保持系完全聚合在一起,说明经过回交后,不育系和保持系的细胞核基因组之间几乎达到一致,纯度较高,今后可以直接应用于甜菜育种中;另有26对纯度较低,遗传距离较大,还需要继续进行回交至纯合。80份供试材料的遗传距离最大为0.462,最小为0.120。14对聚合在一起的原配组中的不育系之间遗传距离各不相同,今后可选择14对中遗传距离较大的不育系和其异型保持系配制二元不育系,用于杂交种中的母本。加大培育出甜菜新品种的可能性,同时减少了育种工作中的盲目性,有效的提高了甜菜育种效率。     

不同浓度PEG对甜菜种子萌发的影响

为了研究不同浓度PEG-6000在23℃时对甜菜种子萌发的影响,为甜菜种子引发研究奠定基础,本研究利用甜菜种子TD305为试验材料,分别采用浓度为10%、20%、40%和60%的PEG-6000,时间分别为24 h、48 h和72 h对甜菜种子进行处理,对发芽势、发芽率、发芽指数、活力指数进行测定。结果显示,处理时间为24 h时,40%和60%的PEG-6000对甜菜种子萌发有促进作用;处理时间为48 h时,20%和40%的PEG-6000促进甜菜种子萌发;处理时间为72 h时,10%、20%和40%的PEG-6000可促进甜菜种子萌发。PEG处理比对表明,40%PEG-6000浸泡72 h后的发芽势、发芽率和活力指数最高,60%PEG-6000浸泡24 h后的发芽指数最高。常温时,适宜浓度PEG-6000可提高甜菜种子的活力指标。     

苹果酸对甜菜种子的活力影响研究

为了探究更多有利于甜菜种子萌发的引发剂,并测定苹果酸对甜菜种子的引发效果,为甜菜种子加工技术提供有效实验依据。本试验以TD701,TD703,TD801甜菜种子为试验材料,设置5种苹果酸浓度(1、2、5、10、15 mmol/L),共15种处理。测定引发后甜菜种子的发芽势、发芽率、发芽指数和活力指数。结果显示：1 mmol/L的苹果酸可以显著提高TD701甜菜种子的发芽率为67.67%,发芽势为65%,活力指数为199.84;2 mmol/L的苹果酸可以提升TD701甜菜种子的发芽指数为25.51;1 mmol/L的苹果酸对TD801甜菜种子的引发效果最好,其发芽势为93.67%,发芽率为95.33%,发芽指数为39.53,活力指数为316.88;而TD703甜菜种子被不同浓度的苹果酸浸泡处理后,均没有显著提高种子活力指数的效果。苹果酸作为引发剂的不同浓度对不同种子的提高活力指数的作用是不同的,引发效果适宜的浓度是不一致的。     

甜菜种子活力的测定——基于近红外高光谱技术

为保证田间甜菜种子的出苗率和生产潜力,需要在种植前对种子进行活力检测,挑选出活力高的甜菜种子进行推广种植。利用高温处理法对甜菜种子进行老化处理,再基于标准正态变换(SNV)、去趋势校正(DET)、Savitzky-Golay平滑处理(SG)、一阶差分(1D)和二阶差分(2D)5种近红外高光谱预处理方法,构建种子活力智能检测模型得出预测的种子发芽率,再利用老化处理后的甜菜种子进行发芽实验得出实际的发芽率。研究发现,甜菜种子经过一阶差分预处理建立的智能检测模型预测性能最好,其预测准确率达到91.92%。将未处理的甜菜种子的实际发芽率与一阶差分预处理法建立的智能模型预测结果进行对比,发现模型的预测准确率为88.2%。近红外高光谱技术是一种快速、无损的作物种子活力测定的新方法。     

Root Yield and Quality of Sugar Beet (Beta vulgaris L.) in Relation to Plant Population

Introduction of genetic monogerm seed and the advancement of agricultural techniques raised the possibility of eliminating costly thinning operations in sugar beet farming. However, this requires high and uniform seedling emergence to provide prerequisite plant populations in the field. This work investigated the minimum levels of seedling emergence for non-thinned sugar beet farming. The experiment was carried out in a loamy soil to investigate the effects of three levels of emergence (60, 50 and 35%) and two intra-row spacings (8 and 15cm) with or without thinning using seed source of graded viability of cv Eva in 1992 and 1993 under field conditions in Eastern Anatolia. Plant population throughout the growing period was monitored and data were taken of yield and quality parameters. On average, 60, 50 and 35% emergence levels were achieved using seed source of 90, 72 and 54% viability range, which resulted in different levels of plant stands depending on intra-row spacing and thinning. Plant density at harvest ranged between 49 500 and 124 500 ha⁻¹ on average depending on initial establishment, intra-row spacing and thinning. Root yield and sugar yield were the highest at plant stands between 90 000 and 100 000 ha⁻¹, below or above of which declined. Impurity contents (e.g. Na, K and a-amino N contents) and extractable sugar content decreased but sugar content and clear juice purity enhanced as plant stands at harvest increased.     

水引发对甜菜种子萌发以及生理特性的影响

为更好地利用水引发技术提高甜菜种子的萌发效果,以甜菜种子TD802为研究材料,以蒸馏水为引发剂,通过发芽试验测得甜菜种子的发芽势、发芽率、发芽指数、活力指数和临界阈值等,筛选有利于甜菜种子快速萌发的引发方法,并进行生理指标的测定。结果表明,处理9的发芽率(91%)和发芽势(90.67%)最好,处理5的发芽指数(41.89)和临界阈值(21.39)在所有组合处理中最好,处理6的活力指数(447.4)最好。处理3和处理7的相对电导率高,对种子损伤最小。处理6丙二醛含量最低,对逆境条件反应较强。处理8抗氧化酶活性最强,可消除逆境胁迫所产生的过氧化伤害。不同温度、预浸种时间的水引发都对甜菜种子有促进作用,其中处理1引发效果最稳定,能够更好地增强种子活力、提高种子的抗逆性。     

基于磷酸二氢钾不同引发组合对甜菜种子的影响

[目的]为了研究不同引发剂组合对甜菜种子萌发的影响,为种子引发剂筛选提供依据,[方法]本研究利用甜菜种子TD305为试验材料,采用不同引发剂组合和不同浓度对甜菜种子进行处理,对发芽势、发芽率、发芽指数、活力指数进行测定。[结果]结果显示,处理时间为48h时,0.2%硼酸+0.3%磷酸二氢钾和0.5%硼酸+0.3%磷酸二氢钾有利于甜菜种子的萌发,0.8%硼酸+0.3%磷酸二氢钾对甜菜种子萌发有抑制作用。0.2%硫酸锌+0.3%磷酸二氢钾引发效果最好。0.2%硫酸锰+0.3%磷酸二氢钾和0.5%硫酸锰+0.3%磷酸二氢钾的引发效果较好于0.1%硫酸锰+0.3%磷酸二氢钾。[结论] 通过不同引发组合比对分析表明,发芽势最高的组合为0.5%硫酸锰+0.3%磷酸二氢钾,发芽率、发芽指数和活力指数最高的组合为0.2%硫酸锌+0.3%磷酸二氢钾,而0.8%硼酸+0.3%磷酸二氢钾组合的发芽势、发芽率、发芽指数和活力指数均为最低。     

Estimating genetic effects in maternal and paternal half-sibs from tetraploid-diploid crosses in <Emphasis Type="Italic">Musa</Emphasis> spp.

Ploidy manipulations and interspecific crosses have allowed considerable genetic progress in Musa breeding, but estimation of genetic parameters for parental selection remains a major challenge. This study aimed to determine the components of genetic variance and the relative contribution of genetic effects to phenotypic variation of yield and phenological traits in secondary triploid hybrids from tetraploid–diploid crosses. The hybrids were evaluated in two consecutive growth cycles on a tropical forest site. Non-genetic effects accounted for a large fraction of the variation observed for most traits, except bunch weight. Partitioning of genetic variance into additive and dominance components confirmed the predominant role of additive genetic effects on the expression of bunch weight, fruit filling time, fruit length, plant height, and number of leaves while primarily non-additive effects accounted for suckering behavior and fruit circumference. Maternal general combining ability (GCA) effects accounted for the additive genetic variation in plant height and number of leaves, suggesting that selection for these traits should be carried out in tetraploid clones. Conversely, paternal GCA effects were the primary causes of genetic variation for fruit filling time, bunch weight, and fruit length, suggesting that these characters should be selected for in diploid clones. Specific combining ability (SCA) effects were observed for all traits, except fruit filling time, suggesting that additional genetic gain could be achieved through recombinative heterosis for these traits.     

向日葵高密度遗传连锁图谱构建及两种水分条件下芽期性状的QTL分析

干旱胁迫对向日葵发芽出苗有重要影响。以K55×K58组合衍生的187个F6重组自交系为材料,利用SSR、SRAP、AFLP标记构建向日葵高密度遗传连锁图谱,设置正常水分(CK)和模拟干旱(18%聚乙二醇PEG-6000)两种水分条件,调查9个芽期数量性状,PCR扩增株系,构建一张包含17个连锁群、1105个标记(368个SSR、368个SRAP和369个AFLP)的高密度遗传连锁图谱。该图谱覆盖基因组长度3846.0 c M,平均图距3.48 c M,连锁群长度147.6~295.5 c M,每个连锁群标记数10~165个。两种条件下检测到33个QTL,其中干旱条件下检测到发芽指数、发芽率、胚芽长、胚根长、胚芽鲜重和胚根鲜重6个性状的14个QTL,可解释6.1%~14.0%的表型变异;正常水分(CK)条件下检测到发芽势、胚根长、胚芽鲜重、胚根鲜重、胚根干重和胚芽干重6个性状的19个QTL,可解释6.1%~25.8%的表型变异。两种水分条件下检测到Qefw5-1、Qefw5-2、Qefw5-4、Qrfw5、Qrfw10和Qrl9共6个QTL的遗传贡献率超过10%,此外,还检测到9个影响干旱胁迫与正常水分条件下性状差值的QTL,可能对抗旱性有直接贡献。这些QTL可为向日葵芽期抗旱分子设计育种研究提供重要参考。     

过氧化氢、硼酸、PEG对甜菜种子萌发的影响

为了研究不同引发剂对甜菜种子萌发的影响,为种子引发剂筛选提供依据,本研究利用甜菜种子TD802为试验材料,采用不同浓度不同引发剂组合对甜菜种子进行处理,对发芽势、发芽率、发芽指数、活力指数进行测定。结果显示,处理时间相同时,不同浓度不同组合引发剂的引发效果也有差别。通过不同引发组合比对分析表明,8%过氧化氢和40%PEG组合处理的发芽势最高,5%过氧化氢处理的发芽率最高,3%过氧化氢和0.01%硼酸组合处理的发芽指数最高,8%过氧化氢和0.01%硼酸组合处理的活力指数最高。     

不同遗传体系基因效应对水稻籽粒碳氮代谢的影响

选用6个不同类型的水稻品种（系）,按完全双列杂交设计（6×5）配成一套亲本、F1和F2 3个世代的遗传材料。采用包括种子、细胞质、母体植株三套遗传体系的种子性状遗传模型和统计分析方法,分析了稻米可溶性糖含量、全氮含量、糖氮比3个性状的遗传特点。遗传方差分析结果表明,可溶性糖含量和全氮含量两性状的表现同时受到种子、细胞质、母体植株三套遗传体系的控制,其中可溶性糖含量和主要受制于二倍体母体植株核基因的显性效应;全氮含量、糖氮比主要受制于种子核基因的显性效应。遗传率和选择响应分析结果表明,可溶性糖含量、糖氮比的遗传率较小,对其进行选择不易奏效;全氮含量以直接狭义遗传率为主,采用单粒选择易取得较好效果。     

4种引发剂对不同甜菜种子的引发影响

为了测定不同的引发剂对不同甜菜种子引发的效果,为甜菜种子包衣剂物料筛选提供依据。研究以4种甜菜种子为试验材料,选用4种试剂对种子进行处理,检测其发芽势、发芽率、发芽指数及活力指数。结果显示,处理后4种甜菜种子的发芽势与对照组相比,分别增加了12%~17.67%、0%~23%、7.34%~22.34%、4.34%~10.00%;处理后4种甜菜种子的发芽率与对照组相比,分别增加了-2.33%~9.67%、-5.00%~0.33%、-4.00%~-0.33%、-11.66%~4.00%;处理后4种甜菜种子的发芽指数与对照组相比,分别增加了6.56~13.27、-2.32~18.26、9.12~23.72、4.16~12.37;处理后4种甜菜种子的活力指数与对照组相比,分别增加了95.45~172.92、2.83~223.22、106.93~324.93、53.99~254.08。研究结果表明,4种处理对种子的活力指数有促进作用,同一处理对于不同种子的引发效果有所不同。     

Correlation between polyovules and number of pistil lobes (stigmatic rays) in sugar beet (Beta vulgaris L.)

The polyovules phenomenon in sugar beet has the same importance for breeding as multigermity, because only mono-ovulic monogerm plants can be used for mechanized cultivation. The polyovules trait was investigated in two Japanese lines, mono-ovulic line NK-219-O and polyovulic line NK-183-cms. Plants of the former had three pistil lobes (stigmatic rays) in each flower, a single ovule per ovary, a single seed in the mature fruit and a single seedling germinated in subsequent tests. Plants of the latter had 5–6 pistil lobes in each flower, 2–3 ovules per ovary, double-seeds and double-seedlings. The correlations between a Pistil Lobes Index (PLI) and thenumber of ovules per ovary, percentage of double-seeds inan X-ray test, and percentage of double-seedlings in germination tests were 0.885, 0.838, and 0.749, respectivelyindicating close associations. These results are important both in sugar beet breeding for indirect selection to eliminate the undesirable polyovules trait and for botanicalinvestigations of the relationship among different parts of the gynoecium.     

不同浓度柠檬酸对甜菜种子的引发影响

为了研究柠檬酸作为引发剂对甜菜单粒种引发的影响效果,并为甜菜种子包衣剂物料的选择提供依据。试验以甜菜单粒种1113×NY051为材料,不同浓度柠檬酸为引发剂,用直接测量法得到发芽势、发芽率等数据。结果表明,处理甜菜单粒种时,不同浓度柠檬酸和不同时间梯度的9个处理都能够有效地促进材料1113×NY051的发芽势、发芽率、发芽指数和活力指数,降低电导率。其中,5 mmol/L柠檬酸对甜菜种子1113×NY051在8、12、24 h 3个不同时间情况下的发芽势、发芽率、发芽指数和活力指数指标均高出对照组(CK),电导率低于对照组(CK)。不同浓度的柠檬酸能显著促进种子萌发,随着处理时间的变化和试剂浓度的不同对引发效果均有不同影响。     

Genetic impacts of fiber sugar content on fiber characters in Sea Island cotton, Gossypium barbadense L.

A genetic model with additive effect, dominant effect, additive × additive effect, and their interaction with environment effect (GE) was employed to analyze the 2-year data of F₁ and F₂ hybrids from 5 × 4 diallel cross, whose parents were Sea Island cotton with different fruit branch types. Unconditional and conditional genetic variances were analyzed to demonstrate genetic impacts of fiber sugar content on fiber characters. Results of unconditional genetic variances showed that dominance × environment interaction effect and additive × additive epistatic effects mainly controlled the genetic variation of fiber sugar content, and environment influenced the inheritance of fiber sugar content. Fiber uniformity, fiber elongation, and fiber micronaire were mainly controlled by dominance × environment effects. Fiber strength was mainly controlled by the interaction of additive × additive epistatic effects and the environment. Analysis of correlation coefficients indicated that the varieties or hybrids with high-fiber sugar content had short fiber, low-fiber uniformity, strength, and fineness, which indicated the close co-variation between fiber quality traits and fiber sugar content. Relatively better fiber quality traits could be obtained effectively through selecting parents with low-fiber sugar. Fiber sugar content of different parents had different genetic effect on fiber quality traits.