Effects of High Soil Temperature and Water Stresses on Malian Pearl Millet and Sorghum during Seedling Stage

Pearl millet ( Pennisetum americanum [L.] Leeke) and sorghum ( Sorghum bicolor [L.] Moench) can suffer from poor stand establishment under conditions of high soil temperature and water stresses. A line source sprinkler irrigation system and a charcoal pit technique were used to evaluate stand establishment and high correlations existed between the two methods. It may be possible to use the charcoal pit technique as a predictive tool in drought resistance breeding programs.     

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。     

钠盐胁迫对甜高粱种子萌发及幼苗生长的探究

为探讨甜高粱种子在不同钠盐胁迫下的萌发特性,本研究以‘辽甜1号’甜高粱种子为材料,采用不同浓度钠盐(NaCl,Na HCO3,Na2SO4及其复合钠盐)溶液进行处理,分析比较甜高粱种子萌发阶段对不同钠盐胁迫的响应特性。结果表明,随着盐浓度的增加,总体上甜高粱种子的发芽率、发芽势、发芽指数、活力指数等萌发指标呈现逐渐降低趋势,不同浓度的钠盐胁迫均显著抑制甜高粱种子的干物质转移和早期幼苗的生长(p<0.05),对幼根的抑制高于幼芽。主成分分析(PCA)结果表明,PC1主要包含芽干重、根干重、根长、活力指数,代表"生长综合因子"(85.87%),PC2主要包含发芽率、发芽势、发芽速度,代表"速率综合因子"(8.36%)。二者共同解释12个萌发指标的94.23%的信息。运用隶属函数法评价不同浓度钠盐胁迫下甜高粱种子的毒害作用,在Na+浓度相同的条件下,不同组成钠盐对甜高粱种子萌发的抑制程度高低为NaHCO3>复合钠盐>NaCl>Na2SO4。     

Comparative Effects of Salt and Water Stress on Seed Germination and Early Embryo Growth in Two Cultivars of Sweet Sorghum

In semiarid regions of the Mediterranean basin, water and salinity stresses restrict crop establishment. The effects of salt and water stress on seed germination and early embryo growth (radicle and shoot growth) were investigated in laboratory in two cultivars of sweet sorghum [Sorghum bicolor (L.) Moench] – cv. ‘90‐5‐2′ and cv. ‘Keller’ – to verify how these stresses may limit crop growth during the very early stages of growing season. Six water potentials (ψ) of the imbibition solution (from 0 to ?1.0 MPa) in NaCl or polyethylene glycol (PEG) for salt and water stress tests, respectively, were studied. Daily germination was recorded, and radicle and shoot lengths and dry weights (DWs) were measured 2 days after initial germination. Seed germination was reduced (8–30% lower than control) by water stress at ψ 相似文献   

高粱原生质体的制备及转化方法研究

以高粱幼苗为材料,利用1%的纤维素酶Cellulose R10和0.75%的果胶酶Macerozyme R10处理高粱幼茎,对比不同的酶解时间,发现酶解7h原生质体浓度最高、质量最佳。以经过氯化铯密度梯度离心法获得的高纯度质粒对获得的原生质体进行转化,用激光共聚焦进行荧光观察,结果显示,GFP和YFP在全细胞表达。本研究首次建立了高粱以高粱幼茎为材料的原生质体制备及转化体系,其方法简单、高效,可以用于高粱基因功能研究。     

Interaction of Salinity and Temperature on the Germination of Sorghum

Laboratory studies were conducted to investigate the effect of salinity × temperature interactions on the germination of sorghum. Sorghum bicolor (L.) Moench. Sorghum seeds were sown in petri dishes with saline solutions of varying concentrations (electrical conductivities of 0.01, 6.4, 12.2, 17.4, 22.6, 27.2, 32.1, and 37.2 dSm^-1) prepared with NaCl. The germination responses of the seeds were determined over a wide range of temperatures (15, 20, 25, 30, 35 and 40 °C) for a period of 8 days. Salinity × temperature interactions were highly significant at each counting date. Although, increased salinity resulted in decreased germination percentages, the detrimental effect of salinity was generally less severe at higher temperatures. Germination rate index, computed from germination counts taken every 2 days, was influenced by salinity and temperature in a similar pattern as final germination. Seed germination was more tolerant to salinity at germination temperatures of 30–40 °C than at 15–25 °C.     

Moisture Stress Effects on the Yield and Water Use of Sorghum Hybrids and their Parents*

Little is known of the relationship between hybrids and parental material with respect to water use and drought resistance. Responses of sorghum (Sorghum bicolor [L.] Moench) F₁ hybrids to moisture deficits are partially determined by parental material. The yield and water use of six sorghum hybrids and their respective male and female parents were evaluated under stressed and well irrigated conditions during 1980 and 1981 at Tucson, Arizona. The soil was Comoro loamy sand (coarse-loamy, mixed, calcareous, thermic typic Torrifluvent) with an average available soil moisture of 16 % at field capacity. Changes in soil moisture were monitored semi-weekly by neutron modulation. Meteorological data were collected daily. The 1980 season had higher maximum temperatures and pan evaporation than the 1981 season. Differences in cumulative water use among entries were apparent within the same water treatments during 1981. Mean cumulative evapotranspiration (ET) for the stressed treatment was 248 and 281 mm for 1980 and 1981, respectively, and ET under well irrigated conditions was 419 and 528 mm for 1980 and 1981, respectively. Hybrids produced greater grain yield than their parents under both water treatments. This was due to greater seed number for hybrids. Seed numbers were more stable for hybrids over both treatments than for parents. Hybrids four and seven had the greatest grain yield in 1980 and 1981, respectively, under stressed conditions. Water use efficiency (WUE) was significantly different within water treatments but was not so between the irrigated and stressed treatments. Hybrids WUE was generally greater than that of parents except for hybrid five under irrigated conditions in 1981. Hybrids with WUE and stable yields were not necessarily reflective of parental material under stressed and non-stressed environments.     

高粱叶片及其它营养器官细胞形态的初步观察

运用细胞离析法对高粱两个品种各叶位叶片细胞形态的观察表明,随叶位升高,三环以上的多环细胞所占的比例有增加趋势,但中部叶位的略有下降。叶肉细胞随叶位升高逐渐变小,但品种间叶肉细胞高度的变化趋势却有不同。冀杂6号叶片表皮气孔密度随叶位升高而增加,而y2203的却差异不大。高粱叶鞘薄壁细胞的形态与叶片细胞的显著     

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     

Respiration and Growth of Sorghum and Sunflower under Predicted Increased Night Temperatures1

Little information exists concerning how crops will respond to the predicted increased night temperatures. The objective of this work was to determine if respiration and growth of sorghum [Sorghum bicolor (L.) Moench], a C, plant, and sunflower (Helianthus annuus L.), a C₃ plant, are affected when the night temperature is increased by 5°C compared to the long-term (19 year) average night temperature in June in Kansas. Sorghum and sunflower were grown in two walk-in growth chambers with either the ambient night temperature (21C) or a high night temperature (26C). Day temperature was the same for all plants (27C). Both sunflower and sorghum had higher respiration rates under the elevated night temperature than under the ambient temperature. The average respiration rate of sunflower grown under elevated night temperature increased by 19% (0.89 vs. 0.75 μmol m^?2 s^?1) and that of sorghum by 44 % (0.52 vs. 0.36μmol m^?2s^?1). After 74 days, sunflower plants grown under the ambient night temperature were 30.2 cm taller than sunflower plants grown under the elevated night temperature; sorghum plants under the ambient temperature were 24.8 cm taller. Sunflower plants grown under the elevated night temperature formed flowers one week earlier than those grown under the ambient temperature. Sorghum formed no flowers by 74 days. Results suggest that, if climate change does increase night temperature, respiration will be increased more in C₄, than C₃ plants.     

苏丹草高梁及其杂种的细胞遗传学研究

苏丹草(S. sudanense)与高粱(S.bicolor)均为禾本科高梁属植物,两者的杂种优势明显,杂交种品质好,抗逆性强,在水产、畜禽养殖及资源利用与环境保护上有着广阔的开发利用前景,但两者是否属于同一个种至今存在争议.本文采用去壁低渗.火焰干燥法,分析了2份苏丹草、2份高粱及其3个杂种F1有丝分裂核型,观察了3个杂种F1减数分裂染色体行为和2个杂种F2体细胞染色体数目.结果表明,苏丹草、高粱及其杂种F1均为1A核型,但核型公式不完全相同,苏丹草Sa为2n=18m+2sm(sat),高粱3042A和3042A×Sa F1为2n=20m,其余材料均为2n=20m(sat).苏丹草、高粱及其杂种F1 3者在10条染色体的绝对长臂、绝对短臂、绝对全长、臂比和相对全长上差异均不显著(P0.05),说明苏丹草与高粱在染色体长度上的变化不明显.杂种F1花粉母细胞减数分裂,终变期和中期Ⅰ染色体核型和数目清晰可见(2n=2x=20),配对行为规则;棒状和环状二价体的频率因组合不同而异,Tx623A×S722 F1、3042A×Sa F1和Tx623A×Sa F1棒状二价体频率分别为4.887、5.710和5.126,环状二价体频率分别为5.113、4.290和4.874;在后期Ⅰ,配对的染色体能够正常分离.杂种F2体细胞染色体数目为20(2n=20).因此,苏丹草与高粱的亲缘关系非常近.     

高粱受精过程及其经历的时间

应用常规石蜡切片技术, 对高粱花粉管生长途径、双受精过程及其经历的时间进行研究。结果表明, 高粱开花即授粉,花粉随即萌发, 花粉管进入羽状柱头分支结构的细胞间隙,向下生长于花柱至子房顶部引导组织的细胞间隙中;进入子房腔后,在子房壁与外珠被之间的缝隙中向珠孔方向生长;花粉管破坏一个助细胞后, 在卵细胞与中央细胞之间的空隙中释放连续的球状内容物;两个精核分别进入卵细胞和中央细胞分别与卵核和极核融合。受精过程经历的时间为开花后0.5~3 h左右, 花粉管破坏一个助细胞进入胚囊,并释放精子;1~3 h精核与极核融合形成初生胚乳核, 精卵融合形成合子;4 h左右初生胚乳核分裂;14 h左右合子分裂。4~14 h为合子静止期,该期为物理、化学诱变及花粉管通道法转基因技术实施的合适时间。     

高粱幼叶细胞悬浮系的建立

以高粱无菌苗幼叶为试验材料,对颗粒状胚性愈伤组织的获得、细胞悬浮系的建立及影响悬浮细胞生长的主要因素进行了研究。结果表明：幼叶在MS（Murashige and Skoog）+2mg/L 2,4-D培养基上诱导出的愈伤组织,经2~3次继代筛选后获得了浅黄色、颗粒状胚性愈伤组织;胚性愈伤组织接种于液体培养基中,于25±1℃、黑暗条件下,经45~60d的悬浮震荡培养建立了高质量的细胞悬浮系,细胞生长曲线呈“S”型,细胞密度可达6.45×10 ⁵~5.08×10 ⁶个/mL以上,活细胞率可达72.76%,近圆细胞率可达87.50%;培养基的基本成分、激素种类和水平对悬浮细胞生长状态有很大的影响,相比1/2MS培养基,MS培养基为适宜的培养基,2,4-D对保持细胞系的稳定增殖至关重要,适宜的浓度为1mg/L;培养液中加入0.5mg/L KT或6-BA会造成悬浮液褐化,影响悬浮细胞的生长;最适宜的细胞悬浮培养基为L2培养基（MS+1mg/L 2,4-D,30g/L蔗糖,pH5.8）,震荡培养转速为110~120r/min,继代周期为7d,新旧培养基的接种比例为2∶1。     

高粱无融合生殖系2083自主结实特性及胚胎学研究

以2083为试材,SSA-1为无融合生殖系对照,三尺三为有性系对照,采用去雄鉴定其自主结实率;杂交后代测验,鉴定其无融合生殖频率;以及与胚胎学鉴定方法相结合,对高粱兼性无融合生殖系2083进行了研究。结果表明,2083在与其他品种杂交形成真杂种的同时,也能自主结实,具有兼性无融合生殖的性质;其自主结实率为10.48%,比     

水稻与高粱属间远缘杂交花粉管行为观察

水稻和高粱是禾本科的两个异属作物,因其遗传距离较远,杂交表现不亲和,结实率极低,难以获得种子。为初步了解水稻与高粱属间远缘杂交花粉管行为,探索该远缘杂交的发生过程,本实验以籼稻珍汕97A×珍汕97B和Ⅱ-32A×Ⅱ-32B两个组合为对照,对珍汕97A×晋江多枝高粱和Ⅱ-32A×晋江多枝高粱两个属间远缘杂交组合的花粉管行为作初步的观察与研究,结果表明:晋江多枝高粱花粉粒能象水稻花粉粒一样在水稻柱头上正常萌发,花粉管在花柱及子房中生长与伸长,有些能最终到达子房的基部;同时高梁花粉管生长也出现诸如不能进入花柱、胼胝质不规则堆积、花粉管末端钝化等一系列的异常表现,致使不少花粉管停滞生长。     

水稻与高梁属间远缘杂交花粉管行为观察

水稻和高粱是禾本科的两个异属作物,因其遗传距离较远,杂交表现不亲和,结实率极低,难以获得种子.为初步了解水稻与高粱属间远缘杂交花粉管行为,探索该远缘杂交的发生过程,本实验以籼稻珍汕97A×珍汕97B和Ⅱ-32A×Ⅱ-32B两个组合为对照,对珍汕97A×晋江多枝高粱和Ⅱ-32A×晋江多枝高粱两个属间远缘杂交组合的花粉管行为作初步的观察与研究,结果表明晋江多枝高粱花粉粒能象水稻花粉粒一样在水稻柱头上正常萌发,花粉管在花柱及子房中生长与伸长,有些能最终到达子房的基部;同时高梁花粉管生长也出现诸如不能进入花柱、胼胝质不规则堆积、花粉管末端钝化等一系列的异常表现,致使不少花粉管停滞生长.     

EMS诱变对高粱出苗及农艺性状的影响

利用不同浓度的EMS对高粱晋粱5号和V4B种子进行不同时间处理,分析EMS处理对高粱出苗及株高、叶片、穗型、育性和成熟期的影响,确定高粱EMS处理的最适条件,为高粱种质创新以及品种培育和改良提供参考。结果表明,晋粱5号和V4B的出苗率、相对成苗率变化总趋势为随EMS浓度升高和处理时间增长而升高,但是与对照相比,部分EMS处理能提高种子的出苗率。株高变异率、育性变异率及成熟期变异率变化总趋势为随EMS浓度升高而升高,而EMS处理对两个种质的叶形变异率和穗型变异率的影响趋势不同。不同浓度EMS应用于高粱诱变育种时,0.20% EMS浸种12h可作为EMS诱变晋粱5号和V4B构建突变体库的适宜条件;0.20% EMS和0.25% EMS浸种12h可分别作为EMS诱变晋粱5号和V4B筛选矮秆突变体的适宜条件;0.25% EMS浸种12h可作为EMS诱变晋粱5号和V4B筛选穗型突变体的适宜条件,以及晋粱5号筛选叶片突变体的适宜条件;0.35% EMS浸种12h可作为EMS诱变晋粱5号和V4B筛选成熟期突变体的适宜条件。     

高粱光敏色素A基因的克隆、蛋白结构与长短日照诱导表达模式

光敏色素是一类红光/远红光受体,对植物光形态建成、外部形态和生理功能等方面起着重要的调节作用。为明晰光敏色素A在调控高粱光形态建成发育过程中的作用,本研究比较分析光温敏感程度不同的高粱品种Btx623、Rio、Tx430和LH645的PhyA基因序列和PHYA蛋白的保守结构域,利用qRT-PCR明确长短日照条件处理下PhyA基因的表达模式。结果表明,Btx623、Rio和Tx430之间PhyA基因序列存在非同义突变,LH645在PhyA基因的第7个外显子上插入了5 bp碱基序列;高粱PhyA蛋白中含有1个PAS-2结构域、1个GAF结构域、1个Phytochrome结构域、2个PAS结构域、1个组氨酸激酶A结构域和1个类似组氨酸激酶的ATP激酶结构;遗传进化树分析表明,单子叶和双子叶植物PhyA蛋白明显聚为2大类,高粱PhyA、谷子PhyA和玉米PhyA1、PhyA2聚为一个亚类,相互间亲缘关系较近,与水稻PhyA同源性相对较远;在短日照(SD)条件下各时期PhyA基因转录水平变化显著,Rio PhyA基因转录水平较Btx623和Tx430变化明显,LH645 PhyA基因转录变化不显著,在长日照(LD)条件下Rio PhyA基因转录水平低于Btx623和Tx430,LH645 PhyA基因转录水平变化不显著。以上结果表明,PhyA受光周期诱导,推测其在高粱光形态建成中起重要调控作用。本研究为进一步解析PhyA基因功能及其在调控高粱光形态建成发育过程中的作用提供理论基础。     

外源亚精胺对盐胁迫下甜高粱(Sorghum bicolor)幼苗的影响

为探究外源亚精胺(spermidine,Spd)对盐胁迫下甜高粱幼苗生长及生理生化的影响,以‘辽甜1号’甜高粱为试验材料,采用不同浓度(0.5 mmol/L,1.0 mmol/L,1.5 mmol/L)的Spd喷施处理165 mmol/L NaCl胁迫下的甜高粱幼苗,测定处理7 d和15 d后甜高粱幼苗的叶绿素、可溶性糖、可溶性蛋白、脯氨酸(Pro)、丙二醛(MDA)含量和净光合速率(Net photosynthetic rate,Pn)、气孔导度(stomatal conductance,Gs)、胞间CO2浓度(intercellular CO2 concentration,Ci)、蒸腾速率(transpiration rate,Tr)以及超氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)、过氧化氢酶(catalase,CAT)和抗坏血酸过氧化物酶(ascorbate peroxidase,APX)活性等生理生化指标,测定处理15 d后甜高粱幼苗的株高、鲜重、干重及幼苗相对含水量。结果表明,盐胁迫显著抑制了甜高粱幼苗的生长及生理生化指标,喷施不同浓度Spd可提高盐胁迫下甜高粱幼苗叶片叶绿素含量、Pn、Gs、Tr,降低Ci,提高可溶性糖、可溶性蛋白和Pro含量,降低MDA含量,提高SOD、POD、CAT和APX活性。说明在盐胁迫下外源喷施Spd能够增强甜高粱幼苗的光合作用,促进幼苗生长,同时增加渗透调节物质含量,提高抗氧化物酶活性以稳定细胞内环境,从而增强甜高粱幼苗的耐盐性,其中1.0 mmol/L的Spd处理效果最佳。本研究为利用外源Spd缓解植物盐胁迫伤害提供科学依据,为提高甜高粱幼苗的耐盐性提供一种新的手段。     

The Response of Four Sorghum Accessions/Cultivars to Salinity During Plant Development

Whole-plant-response of four sorghum accessions to increasing mM NaCl concentrations of 0, 100, and 150 was assessed at three growth stages (GS-1, GS-2, and GS-3), in a sand-culture experiment. Accession comparisons were made on the basis of absolute and relative salt tolerance values. Increasing salinity significantly reduced plant height at GS-1, whilst shoot and root dry weight were less affected. The effect of NaCl on these characters was greater at GS-2 and GS-3, and accessions differed significantly in their responses to salinity. On the basis of plant height data, Giza 114 had the highest absolute salt tolerance at all three growth stages. However based on shoot and root dry weight data, Double TX and Giza 114 were both significantly more NaCl-tolerant than INRA 133 and INRA 353 at GS-2. Based on relative salt tolerance values of shoot and root dry weight, and plant height, Double TX and Giza 114 were more affected by salinity at GS-3 than INRA 133 and INRA 353. INRA 133 and INRA 353 exhibited progressively higher tolerance at all growth stages, and produced more grains than Double TX and Giza 114 , and consequently had higher grain yield per plant. NaCl salinity had little effect on grain weight. Plant sensitivity to NaCl at three growth stages differs in the four accessions, and is genotype-specific. This suggests that there is considerable variation in salt tolerance in sorghum at the adult stage which may be exploited through selection and breeding of plants to effect further improvement in salinity tolerance in this species.