Variability for Salt Tolerance in Sorghum bicolor (L.) Moench. under Hydroponic Conditions

The response of seedlings of 51 Sorghum bicolor accessions to 0, 50, 100, 150, 175, and 200 mM NaCl in solution culture was examined. Plant growth was measured as longest root lengths, maximum shoot lengths, and total plant dry weights after 14 days. Increasing NaCl concentration caused significant reductions in all three characters. Accession response to increasing NaCl also varied. The data suggest that increase in NaCl tolerance in this species through recurrent selection may be possible.     

The Genetic Basis of Variation for Salt Tolerance in Sorghum bicolor (L.) Moench Seedlings

The genetic basis of salt (NaCll tolerance at the seedling stage was examined in eight accessions of Sorghum bicolor (L.) Moench which differed in relative NaCl tolerance. The eight accessions were crossed in all possible combinations. The Nad tolerances of the resulting 56 F: hybrids and their eight parents were assessed after two weeks growth in solution cultures containing 0, 103, and 150mM NaCl. Indices of salt tolerance (relative tolerance) were used for analysis using the diallel method. Both additive and dominance effects appeared to be important for the expression of variation under low and high salinity levels, but the effect of genes with dominance properties was more pronounced. Estimates of narrow sense hentabilities for sail tolerance were appreciable, suggesting that rapid improvement in salinity tolerance is possible in this species using high selection pressures in the F₂ population.     

不同品种甜高粱苗期耐寒性分析研究

低温胁迫是影响甜高粱产量和品质的主要非生物因素之一,为更好地了解低温胁迫下苗期甜高粱耐低温的机制,并服务于甜高粱耐低温品种的选育,本研究以6 个甜高粱品种为材料,对其在低温胁迫及恢复处理后苗期叶片中的各项生理指标进行测定,并以各项指标的抗冻系数作为衡量抗冻性的指标,采用主成分分析法以及聚类分析对抗寒性做出综合评价。研究表明,低温胁迫后,6 个甜高粱品种Pro 含量均不同程度上升;而SOD、POD、CAT活性以及可溶性糖含量却呈现不同的变化趋势,部分品种表现为下降趋势。通过主成分分析以及聚类分析最终将6 个品种分为3 类,‘BJ0603’和‘EN-11’为强抗寒类型,‘EN-12’、‘IMP-2’和‘KFJT-1’为中度抗寒类型,‘BJ0602’为弱抗寒类型。本研究结果为甜高粱抗寒品种的选育提供了一定的理论依据。     

甜高粱叶绿素荧光特性对生物有机液体混合肥的响应

为揭示生物有机液体混合肥对陕北农牧交错区青贮饲草作物光合作用的影响,以甜高粱(Sorghum bicolor L.)为研究对象,通过盆栽控制试验,设置4种浓度的生物活性水(BMW)(B1、B2、B3和B4,分别为稀释600、400、200和100倍的BMW溶液)和3种浓度的Aidoora溶液(A1、A2和A3,分别为稀释1000、500和300倍的Aidoora溶液)的生物有机液体肥处理,测定比较了不同生物有机液体混合肥下甜高粱叶片叶绿素荧光特性。结果表明:在大多数单一液体肥和混合液体肥下,适宜浓度水平的BMW和Aidoora溶液均能显著提高甜高粱幼苗叶片的PSⅡ最大光量子效率(F_v/F_m)、PSⅡ实际光化学量子效率(ΦPSⅡ)、光化学淬灭系数(qP)和表观光合电子传递速率(ETR),并降低了其非光化学淬灭系数(NPQ),且以有机液体混合肥的促进作用更显著,这说明施加生物有机液体肥后均能提高其叶片PSⅡ光化学效率和光合电子传递速率,而降低了非辐射性热能量耗散。综上分析表明,B2A2相对于其他BMW和Aidoora混合液体肥有利于促进甜高粱幼苗叶片PSⅡ光化学活性。     

高粱耐逆基因SbALDH7的克隆与表达分析

旨在研究高粱(Sorghum bicolor)中的醛脱氢酶基因SbALDH7的序列信息和表达分析。通过PCR和RT-PCR方法,从高粱中克隆SbALDH7基因及其cDNA全长序列。通过网络软件,聚类分析SbALDH7的序列特征,利用半定量RT-PCR,研究其在不同组织和胁迫条件下的表达谱。结果表明：SbALDH7基因含13个内含子,共编码509个氨基酸,其编码的氨基酸序列具有典型的ALDH7结构域特征。SbALDH7的表达受到PEG、Nacl、ABA和低温等胁迫环境诱导上调。组织特异性表达分析显示,在PEG渗透胁迫环境下,SbALDH7在茎、叶中的表达量显著高于根中的表达量。抗旱性有显著差异的6个高粱品种的SbALDH7蛋白序列无差异,但高粱品种的苗期抗性与SbALDH7的表达量间存在显著的正相关,表明SbALDH7的表达对高粱的抗旱性可能起着重要的作用。SbALDH7具备醛脱氢酶家族蛋白典型结构特征,在高粱抗逆过程中起重要作用,可作为提高高粱抗旱耐盐的靶基因应用于作物遗传改良。     

高粱微卫星分析中遗传完整性样本量的确定

采用微卫星分析高粱不同样本量对遗传多样性指数的影响,从而确定最佳样本量,为遗传完整性研究奠定基础。试验设置了10个样本量梯度,对群体的等位基因数目、有效等位基因数目、香农指数、观察杂合度、预期杂合度、多态位点百分数和稀有等位基因频率的变化趋势进行了分析。结果表明,10～40个样本量范围内,等位基因数目、有效等位基因数目、香农指数、多态位点百分数随着样本量的增大而增大;在40个样本量时,等位基因数目、有效等位基因数目和香农指数达到较高值,分别代表了100个群体98.5%的等位基因数、99.1%的有效等位基因数和98.5%的香农指数,之后样本量继续增加,各指标变化不显著。稀有等位基因频率在40个样本量以上,随着样本量的增加数值变化很小。以稀有等位基因频率、等位基因数、有效等位基因数和香农指数为多样性指标,在高粱遗传完整性研究中样本量大小的确定上达到一致性。因此,建议在用SSR技术对高粱进行遗传完整性分析时,样本量要选择40个单株以上。     

Floral Traits and Seed Production of Sorghum A-, B- and R-lines under Chilling Field Temperatures

In A-lines of sorghum ( Sorghum bicolor L. Moench), seed production under field conditions with manual pollination is generally lower than that in self-pollinated B-lines. This may be associated with floral differences. Six pairs of A/B-lines and four R-lines were evaluated during 2005 and 2006 at Montecillo, State of México (2240 m altitude). Rachis length, number of primary branches and fertile flowers per panicle, 100-seed weight, seed number, seed yield and seed set per panicle were evaluated. In the A-lines, the pistil characteristics were also measured and in the male-fertile lines, the size of anthers and the amount and size of viable pollen were recorded. Compared with the A- and B-lines, the R-lines exhibited significantly higher (P ≤ 0.05) numbers of flowers, seed set and seed yield per panicle and they also produced more pollen grains of larger size and with greater viability during their longer flowering period (FP). Between A- and B-lines, there were differences (P ≤ 0.05) in most of the yield traits, which also interacted with year. The proportion of viable pollen in B- and R-lines (75 %) was not considered to be a factor that might account for their low seed production. Chilling temperatures (3.5–8.4 °C) during the FP could have affected stigma receptivity in the three different line types and thus may have reduced seed set in the male-fertile lines.     

高粱育种资源耐瘠性鉴定及评价

通过对高粱育种资源进行全生育期瘠薄胁迫,探讨瘠薄胁迫对高粱主要农艺性状及产量的影响,明确不同高粱资源的耐瘠性,为高粱耐瘠材料鉴选和选育提供支持。试验在2016-2018年4月至10月进行,采用随机区组设计,设置正常和瘠薄胁迫处理,运用耐瘠系数和隶属函数相结合的方法对56份高粱材料的耐瘠性进行综合评价。结果显示,与正常处理相比,瘠薄胁迫下高粱材料生育期延长,株高变大,茎粗、穗长、穗宽、穗粒重和千粒重下降。供试高粱材料各农艺性状瘠薄与对照处理的变异系数为0.10~0.46,其中穗粒重变异最大。56份高粱材料平均隶属函数值为0.23~0.79,鉴定筛选出耐瘠材料BTx378、BSX44和A2早BTx623-5B等。     

高粱与苏丹草杂种优势利用的研究

高粱与苏丹草杂种优势明显,F1单株生物产量性状高于双亲平均值,甚至超过或接近高亲。影响高粱-苏丹草杂交种单株茎叶鲜重的主要因素是主茎粗、叶长;决定单位面积鲜草产量的主要是密度、叶长和单株茎叶鲜重。多年随机区组试验结果表明,杂交种单位面积鲜草产量显著超过苏丹草,并以30万株/hm2为最适种植密度。杂交种营养品     

上海市崇明区两种甜芦粟营养品质差异性分析

以上海市崇明区甜芦粟地方品种甘蔗芦穄（绿皮）和糖穄芦穄（红皮）为研究对象,应用色谱等检测技术初步分析了两种甜芦粟营养成分的种类及其含量。结果表明,两个品种甜芦粟富含营养元素Mg、K、Ca、Na,主要风味氨基酸（天冬氨酸、谷氨酸）和类黄酮类物质。绿皮甜芦粟的脆性和甜度优于红皮甜芦粟,口感较好,且果糖（天然甜味剂中甜度最高的糖,比甜度为1.5）含量较高,达到了3.31%,适于直接榨汁食用,并初步发现红皮甜芦粟黄酮类物质含量高于绿皮甜芦粟,在保健类食品药品的开发领域有一定的潜力。     

Towards Enhancement of Early‐Stage Chilling Tolerance and Root Development in Sorghum F1 Hybrids

Sorghum (Sorghum bicolor L. Moench) is regarded a drought‐tolerant alternative to maize as a bioenergy and fodder crop, but its early‐stage chilling sensitivity is obstructing a successful implementation in temperate areas. While several studies have identified quantitative trait loci (QTL) underlying chilling tolerance‐related traits in sorghum lines, little is known about the inheritance of these traits in F₁ hybrids. We have conducted a comprehensive approach to analyse heterosis, combining ability and the relation between line per se and hybrid performance for emergence and early shoot and root development comprising both field trials and controlled environment experiments including chilling tests. To our best knowledge, this is the first study analysing heterosis for sorghum root parameters under chilling. Our results show that most traits are heterotic and that the mid‐parent values are rather poor predictors of hybrid performance. Hybrid breeding programmes should focus on efficient GCA tests and the establishment of genetically diverse pools to maximise heterosis rather than on a too strict selection among lines based on their per se performance. The medium‐to‐high heritabilities estimated for seedling emergence and juvenile biomass suggest that a robust breeding progress for these complex traits is feasible.     

高粱SSA-1无融合生殖特性及其遗传分析

采用去雄杂交鉴定、遗传分析，对高粱ＳＳＡ－１无融合生殖系的结实特性，无融合生殖频率及其遗传行为进行了鉴定分析。研究结果表明ＳＳＡ－１具有自主结实特性，其自主结实为１３．３－３２．７％。绳索产受两对隐性基因控制，无融合生殖频率为２５．５％－５２．２％，为的兼性无融合生殖类型。该系无杂交不孕性，无融合生殖表达不受授粉方式，父类型等因子的影响，是目前无融合生殖研究以及固定杂种优势的良好基因材料。     

Activation of Antioxidant System by KCl Improves the Chilling Tolerance in Hybrid Maize

As maize is a chilling-sensitive crop, low temperatures during the early stages of development can be injurious to crop growth and development. Prime mechanism behind chilling-induced damage is oxidative stress. This study was undertaken to improve the chilling tolerance in hybrid maize by seed priming with KCl. For priming, seeds of the maize hybrid Hycorn 8288 were soaked in 50, 100 and 150 mg l⁻¹ aerated solution of KCl for 24 h and then re-dried close to original weight. Primed and untreated seeds were sown at 27 °C (optimal temperature) and at 15 °C (chilling stress) under controlled conditions. Seed priming improved the performance of maize under both normal and stress conditions. It was found that the chilling tolerance in maize is well associated with the enhanced capacity of the anti-oxidative system. Priming with KCl significantly improved the chilling tolerance mainly by the activation of antioxidants including catalase, superoxide dismutase and ascorbate peroxidase enzymes. KCl treatments also improved the germination rate and time, root and shoot length, and fresh and dry weights of seedlings compared with control. Soluble sugars and α-amylase activity determined as general metabolic indicators of stress were also improved by seed priming with KCl. Other possible bases of chilling tolerance in maize included maintenance of high tissue water contents, reduced electrolyte leakage and carbohydrate metabolism. Seed treatment with 100 mg l⁻¹ KCl was the best treatment to improve the performance of hybrid maize both under normal and chilling stress conditions.     

QTL analysis of salt tolerance in Sorghum bicolor during whole-plant growth stages

To study the salt tolerance genetics of sorghum, 181 recombinant inbred lines (RILs) were used to locate quantitative trait loci (QTLs) underlying salt stress adaptability. Six traits, namely, plant height (PH), stem diameter (SD), total biomass (TB), stem fresh weight (SFW), juice weight (JW) and Brix, were investigated under normal and salt stress conditions in two years. A total of 53 QTLs for the six traits under both conditions and their corresponding salt tolerance index (STI) were detected and phenotypic variation explained (PVE) ranged from 4.16% to 20.42%. Six of the QTLs, qTB6, qSFW9, qJW9, qBrix2, qBrix10 and qSTI-Brix9, were the main effect QTLs controlling salt tolerance and had a PVE more than 10%. qSFW9 and qJW9 colocalized in the same marker interval as SB5069-UGSM18 and had PVEs of 17.70% and 14.20%, respectively, with positive effects from L-Tian. QTL clusters controlling PH, TB, STI-TB, SFW and JW were consistently mapped in the marker interval of Xcup19-SB4177 on chromosome 7. These locations might serve as target sites for marker-assisted selection (MAS) in improving salt tolerance of sorghum.     

贵州省不同年代糯高粱品种（系）农艺性状演变分析

以贵州省不同年代酿酒用糯高粱品种（系）为研究对象,采用随机区组试验设计,对其农艺性状、产量构成以及抗性差异进行分析,结果表明：随着年代更替,贵州省酿酒用糯高粱单产逐步提高。新品种（红缨子、黔高8号）较老品系（黑壳糯、红壳糯）平均单产增幅25%以上;穗粒数、穗粒重增加显著,增幅分别为51.7%、62.7%;主穗一、二级枝梗数增加幅度分别为19.8%、62.7%;株高降低24.9%,茎粗增加9.5%;节间数增加0.9个,节间长缩短13.3cm;单株叶面积和叶面积指数增加显著;倒伏率、发病率下降显著,成穗率明显提升。各指标相关性分析显示,产量与穗粒数、穗粒重,穗粒数与主穗一、二级枝梗数呈极显著正相关;产量与株高、倒伏率极显著负相关,与茎粗正相关,相关系数分别为-0.981、-0.970和0.928,株高、茎粗与倒伏率相关显著,相关系数分别为0.964和-0.910;产量与叶面积指数正相关,与发病率显著负相关。总的结果表明,主穗一、二级枝梗数的增加提高了糯高粱的穗粒数,植株株高的降低、茎粗的增加促进了抗倒性的提升,抗病性的提升保证了后期叶片光合作用的持续进行,最终提高了糯高粱产量。     

Molybdenum Uptake and Nitrate Reductase Activity in Sorghum (Sorghum bicolor L. Moench). Evidence for Heterosis

The absorption of Mo by the roots and. transport to the shoot of intact seedlings of a sorghum hybrid and its parent cultivars were measured for 3 h from 10 to 100 μmol ammonium molybdate. The patterns of absorption revealed hybrid vigour and the hybrid followed the patterns of the male- parent 168. Studies on the effects of different amounts of Mo on the nitrate reductase activity also showed the occurrence of hybrid vigour in the- hybrid CSH-7.     

Stay green trait in grain sorghum: relationship between visual rating and leaf chlorophyll concentration

Post‐flowering drought tolerance is referred to as the stay green trait in sorghum. Plants with stay green resist drought‐induced premature plant senescence. In breeding programmes, stay green is evaluated under limited irrigation, post‐flowering moisture‐stress field conditions and visually scored at or soon after physiological grain maturity. The objective of this study was to investigate the relationship between the stay green rating and total leaf chlorophyll content. The parents B35 and Tx7000, and their 98 F, recombinant inbred lines were evaluated in replicated field trials under limited (post‐flowering stress) and full‐irrigation (non‐stress) conditions. After scoring the stay green trait of stressed plants, total leaf chlorophyll contents were measured with a chlorophyll meter (SPAD values) and a spectrophotometer method. The SPAD value had a significant linear relationship with total leaf chlorophyll (R²= 0.91) and with visual stay green rating (with R²= 0.82). Relative water content in top leaves of the stay green lines was about 81%, much higher than non‐stay green lines (38%), indicating that the stay green lines kept the stalk transporting system functioning under severe drought conditions, The results indicate that visual stay green ratings were a reliable indicator of leaf senescence an should be useful to sorghum breeders in evaluating progeny when breeding for drought tolerance.     

Determination of Differences in Chilling Susceptibility of Two Soybean Varieties by Means of in vivo Chlorophyll Fluorescence Measurements

Chilling susceptibility of two soybean varieties, i.e. cv. Maple Arrow and cv. Evans , in the vegetative state (V 3.0) was determined by measuring in vivo chlorophyll fluorescence of leaves exposed to low positive temperatures. In the more susceptible variety Maple Arrow quite distinct deviations from the reference fluorescence data are seen at temperatures between 6.5 and 4.8°C, but not until 5.5. to 2.5°C in the variety Evans. Fluorescence characteristics, i.e. the fluorescence decrease Rfd, the appearance of low-waves, the photochemical quenching coefficient at steady-state and the initial slope of the non-photochemical quenching coefficient qNP indicate that the two varieties differ in their susceptibility by about 1-2°C at this stage of development. Our results suggest that measurement of in vivo chlorophyll fluorescence might serve as a suitable rapid monitoring method of pre-screening soybean varieties for chilling susceptibility, as required in plant breeding.     

中国高粱地方品种遗传多样性评价及中、外高粱遗传变异水平比较

利用32个高粱(Sorghum bicolor L.)核基因组多态性SSR(simple sequence repeats)位点,以69份国外品种为对照,对12个地区的184份中国高粱地方品种进行了遗传多样性分析。研究结果表明,中国高粱的遗传多样性明显低于国外高粱。中国高粱和国外高粱的等位基因丰度(R_s)和基因多样性(H_e)分别为9.81、0.629和11.52、0.745。中国高粱的遗传多样性明显低于东非(He=0.732)、北美(He=0.707)和南亚(He=0.712)高粱,与南非高粱相当(He=0.609)。不同地区中国高粱地方品种遗传变异水平存在明显差异,12个地区高粱种质等位基因丰度在3.64~4.88之间,基因多样性值在0.517~0.714之间。吉林高粱地方品种遗传变异最为丰富(He=0.714),与北美、南亚高粱相当。中国高粱与国外高粱之间遗传分化明显,而中国高粱地方品种地区间和类型间分化极弱。主成分分析(PCA)能够明显区分中外高粱种质但不能将中国高粱按地区或类型分开。分子方差分析(AMOVA)表明,中外高粱间的遗传变异占全部参试材料遗传变异的20.43%。中国高粱遗传变异主要存在于地区内材料间(占总变异91.94%)或生态区内材料间(占总变异94.97%)。在品种类型方面,中国高粱绝大部分遗传变异存在于穗型内材料间(占总变异97.93%)。本研究支持中国高粱外来说的观点。     

高粱苗期耐盐碱性QTL定位

为定位混合盐碱胁迫下调控高粱苗期性状的QTL位点,发掘耐盐碱基因位点及其紧密连锁标记。以耐盐碱和盐碱敏感组合BJ-299×Tx622B构建的F2群体为材料,采用SSR标记技术和区间作图法对170个F2∶3家系进行高粱苗期相对存活率(RL)、相对干质量(RDW)、相对鲜质量(RFW)和相对苗高(RSH)的QTL分析。结果表明,试验材料耐盐碱性状符合数量遗传的特点,共定位到3个QTL位点(q SAT-A、q SAT-D和q SAT-J)调控高粱苗期耐盐碱性状,分布在A、D和J染色体上,位于标记Sam27281~Sam22486、Sam11433~Sam78379和Sam62346a~Sam38392。q SAT-A和q SAT-D同时调控RL、RDW、RFW和RSH性状,表型贡献率分别为14.3%,9.7%,8.0%,10.6%和8.7%,13.5%,18.8%,13.6%;q SAT-J位点调控RL性状,贡献率为7.3%。q SAT-A和q SAT-D为调控高粱苗期耐盐碱性状的重要位点,有望在高粱耐盐碱性状分子标记辅助育种发挥重要作用。