花生种子芽期耐低温相关基因克隆

利用GeneFishing技术获得耐低温花生品种花育44号种子在常温与低温诱导下的差异表达基因(differentially expressed genes,DEGs)ACP20和ACP2。BLAST比对后发现ACP20基因与花生油质蛋白基因同源性达99%,ACP2基因与花生nifU-like(铁硫簇蛋白)蛋白mRNA同源性达99%,说明油质蛋白和nifU-like蛋白可能与花生对低温逆境胁迫的抗性有关。通过RACE技术从该品系获得相关基因的完整编码区,对其进行生物学功能预测,为探讨花生耐低温分子机制乃至培育耐低温花生新品种奠定了基础。     

高油酸花生萌发期耐冷性综合评价及种质筛选

为筛选高油酸花生萌发期耐冷鉴定指标,构建高油酸花生萌发期耐冷性综合评价体系,挖掘高油酸花生耐冷种质资源。本研究利用隶属函数法、主成分因子分析法、相关性分析及聚类分析法对56份高油酸花生种质资源进行耐冷性综合评价及耐冷种质筛选。结果表明,11个耐冷鉴定指标按贡献率大小依次为露白萌发因子、发芽时间因子及子叶鲜重因子,发芽指数及萌发耐冷指数可以作为高油酸花生萌发期耐冷性的最优鉴定指标,高油酸花生种质资源萌发期耐冷性强弱受多指标影响。高油酸花生萌发期耐冷性状综合评价D值范围为0.080~0.754,均值为0.497,不同高油酸花生品种萌发期耐冷性存在较大差异。56份高油酸花生种质资源分为5个耐冷级别,筛选到萌发期耐冷较强材料1份、中等耐冷材料20份、耐冷较差材料29份、耐冷差材料5份及冷敏感型材料1份。本试验筛选到的耐冷种质可以作为高油酸花生耐冷育种和耐冷机理的研究材料。本研究为探明高油酸花生种质资源耐冷性提供了理论参考。     

24份山西花生资源芽期和苗期耐寒性鉴定

为评价不同山西花生资源芽期和苗期的耐寒性差异,本研究以24份山西花生资源为试验材料,在常温(25℃)和低温(2℃处理花生种子、10℃处理花生幼苗)胁迫下分别测定种子的发芽率和发芽指数以及苗期的逆境生理指标,并以低温与常温测定值的比值作为耐寒性的评价指标,最终将各性状比值进行聚类分析。结果表明,芽期相对发芽率0.90,相对发芽指数0.80的花生资源有4份;耐寒性强的花生资源的脯氨酸含量,SOD、POD活性的增幅均大于耐寒性弱的资源;通过聚类分析将24份花生资源分为3类,第一类为耐寒性,包括4份,第二类为中间型,包括8份,第三类为敏感性,包括12份,芽期结果与聚类分析结果综合比较筛选出3份耐寒性品种,分别为汾西小粒、文水花生、临县多粒。本研究为进一步探究不同花生资源在不同时间段低温逆境下的苗期生理变化提供了理论参考依据。     

低温对甜玉米种子氧化酶活性的影响及相关基因表达分析

为了探究低温对甜玉米种子萌发的影响以及不同品种抗寒性的差异机制,本研究以1组甜玉米自交系的种子为材料,通过低温胁迫下的萌发试验,筛选出耐寒性较强的1132和对低温敏感的国区T12,分别研究了其在10℃和26℃条件下萌发过程中超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)等3种抗氧化酶活性及其相关基因表达水平的变化。结果表明,耐寒自交系1132的抗氧化酶活性整体高于敏感系国区T12。随着低温胁迫时间的延长,1132吸胀萌发的种子中SOD、POD和CAT活性总体呈增加趋势,中间有波动,在胁迫后24h,3种酶的活性均高于常温对照;而国区T12在低温胁迫后SOD和POD大体为增加趋势,CAT则持续降低,在胁迫后24h只有SOD的活性高于常温对照。1132的SOD3、SOD9、CAT1相对表达量较国区T12高,虽未表现出与其酶活变化趋势严格一致,但低温胁迫使其整体表达呈先降低后增加趋势。2个品种的相对表达量均低,可能是POD3并非表达POD的关键基因,因此在酶活性和基因表达方面可能造成了两者抗寒性和发芽率的差异。综上,玉米种子萌发期的耐寒性与抗氧化酶活性密切相关,而抗氧化酶活性的变化则可能是一个非常复杂的表达调控过程。本研究结果不仅为鉴定和筛选耐低温种质资源、培育高发芽势种子提供理论和技术支持,同时为防御玉米低温引起的冷害提供参考。     

苗期低温胁迫对番茄生长及果实畸形发生的影响

为探讨低温对番茄生殖生长的影响,为耐低温番茄品种选育及栽培措施提供理论依据。对9个不同基因型番茄材料分别进行了低温下的种子发芽试验、苗期耐寒性鉴定、苗期自然低温处理对后期番茄生长及坐果率和畸形果发生的影响试验。结果表明,低温使部分基因型番茄种子的发芽率降低,延长了发芽时间;不同基因型番茄材料苗期对低温反应不同,表现出较大差异;田间自然低温对番茄植株生长速度、开花、结果均造成不同程度的影响。综合分析试验结果认为,番茄材料LA3969耐低温综合能力最强,德奥特7845综合表现较好,其次是JX-701和华美168,其余材料耐低温综合能力表现一般,对照7363表现最差。     

玉米种子的活力鉴定

玉米早春播种常遇低温。玉米种子在低温下吸水时易发生吸胀冷害,轻者影响种子出苗的整齐度,减少成苗,重者使种子完全丧失发芽能力。在低温情况下,种子的生理及生化活动也减慢,细胞内含物外渗现象都变得严重;若温度高,真菌类生长速度快,种子便易受到感染,出苗率下降。不同玉米品种在低温下的发能力差异显著,在很大程度上决定着种子发芽过程的耐冷性。     

二十一份重庆花生种质资源的农艺性状评价

为了给本地花生种质资源的利用提供理论依据,"第三次全国农作物种质资源普查与收集行动"重庆项目组于2015—2017年,从重庆市12个区县收集了地方花生种质资源21份,对这批花生资源的9个农艺性状进行调查统计,并用SPSS20.0软件进行相关性分析。结果:21份花生种质资源在重庆地区的结果枝数、单株饱果数、主茎高、单株产量、侧枝长等性状变异程度高,表现出明显的遗传差异,在育种上有较大利用空间;影响单株产量的主要农艺性状是结果枝数和单株饱果数。     

辣椒不同品种种子萌芽期耐低温性及评价方法研究

以108个辣椒品种为试材, 测定了低温(18 ℃)下种子的相对发芽势、相对发芽率、相对胚根长、相对发芽指数和相对活力指数, 并采用极点排序法对辣椒不同品种的耐低温性进行综合评价。结果表明: 辣椒 不同品种种子萌芽期的耐低温性不同, 相对发芽率、相对发芽指数、相对胚根长和相对活力指数4项指标在不同品种间差异达显著水平(P<0.05)。选用上述4个指标, 采用极点排序法计算得到各品种的综合评价得分, 根据综合评价得分将108个辣椒品种分为10个耐低温品种, 9个低温敏感品种, 其余为中度耐低温品种。辣椒种子相对发芽势、相对胚根长与综合评价得分的相关性达到显著水平; 相对发芽率、相对发芽指数、相对活力指数与综合评价得分的相关性达极显著水平, 且相对活力指数与综合评价得分的相关性最高(r=0.899 9)。通过测定低温下辣椒品种萌芽期相关性状指标, 采用极点排序法可对辣椒种子萌芽期耐低温性进行快速、准确的评价。     

不同来源马棘种子和苗期性状的变异研究

为了揭示马棘种子和苗期性状的变异规律,筛选马棘新品种选育的优异种质,对巫山地区19个马棘种质种子和苗期共10个性状进行调查分析。结果表明,马棘不同种质间的种子和苗期性状有显著差异(P0.05),种子平均变异系数7.73%～12.88%。相关性分析表明,种子长、种子宽、发芽率与种子千粒重呈极显著正相关,苗高与地上生物量和地下生物量呈极显著正相关;采用主成分综合得分法筛选出12号、25号、16号3个得分较高的资源;应用聚类分析将19个种质聚为3类,其中第Ⅱ类综合表现较好,包含较大苗高、种子宽、地上及地下生物量。     

TTC染色指数配合Logistic方程鉴定山葡萄种质抗寒性

为了能简便、准确地鉴定山葡萄种质抗寒性,该研究以40份山葡萄种质1 a生休眠期枝条为试材,利用连有图像分析软件的扫描仪对各低温处理下枝段染色图像进行可视化评估,配合Logistic方程建立回归方程,确定其低温半致死温度。结果表明,枝段染色指数随温度降低而下降,染色指数变化规律符合Logistic方程;40份山葡萄种质低温半致死温度在-39.41～-29.75℃范围内,拟合度在0.956 4～0.999 3范围内,种质抗寒性差异明显;各种质低温半致死温度与其平均隶属度及田间萌芽率均呈极显著负相关,相关系数分别为-0.883 03和-0.876 70。研究结果证明TTC染色图像可视化评估配合Logistic方程鉴定山葡萄种质抗寒性可行,同时为山葡萄种质抗寒性评价及抗寒亲本选择提供了简单、可靠的鉴定方法。     

Variation in the seed and oil yields and oil quality in the Indian germplasm of opium poppy Papaver somniferum

The variation in the seed shape, colour and yield, and content, yield and fatty acid composition of seed oil of 109 accessions of opium poppy Papaver somniferum, (majority of them Indian land races), was investigated. The seeds were white, pale yellow or light brown in colour, reniform or round in shape and varied in size up to three fold. The oil content, seed and the oil yield varied between 26 to 52%, 1.0 to 7.4 g/plant and 0.4 to 2.7 g/plant, respectively. The % content of palmitic, oleic and linoleic acid in the seed oil ranged between 9.3 to 40.0%, 7.5 to 58.4% and 0.7 to 72.7%, respectively. On average basis, the levels of major fatty acids in the seed oil were: oleic (37.1%) > palmitic (27.3%) > linoleic acid (17.2%). The palmitoleic, stearic and linolenic acids were present in the oils of only some of the accessions. Two of the accessions yielded linoleic acid rich seed oil of about the same quality as soybean and maize oils, and in four accessions, the proportion of palmitic, oleic and linoleic acids was roughly equal. The palmitic acid was relatively less and linoleic acid more in the seed oil from accessions rich in oil content. The oil that contained higher amount of oleic acid also contained higher amount of palmitic acid and relatively lower amount of linoleic acid. The correlation analyses revealed a strong positive relationship between seed yield and oil yield (r = +0.81), oil yield and oil content (r = +0.54) and oleic acid and palmitic acid content in the seed oil (r = +0.49), and a weak positive relationship between oil content and linoleic acid content of oil (r = +0.24), and a negative correlation was observed between oil content and palmitic acid content (r = –0.32), palmitic acid and linoleic acid (r = –0.55) and oleic acid and linoleic acid contents of oil (r = –0.68). The observations have permitted selection of accessions that are high seed and oil yielding and/or rich in linoleic, palmitic and oleic acids or containing palmitic, oleic and linoleic acids in about equal amounts.     

Variability of fat content and fatty acids profiles in seeds of a Polish white lupin (<Emphasis Type="Italic">Lupinus albus</Emphasis> L.) collection

The paper assess the variability of fat content and fatty acids profiles in seeds of a white lupin (Lupinus albus L.) domestic collection. The initial material comprised 371 accessions originated from 30 countries of Europe, Asia, Africa, North- and South America and Australia. According to data given by accession donors the material is divided into four classes of origin: wild lines, landraces, lines created by man and cultivars. Variability of fat content and fatty acids composition were estimated in seeds of each accession. The average fat content for analyzed collection is 9.81%. The broadest range of fat content was noticed for landraces and cultivars as compared to narrowest represented by lines created by man. Fat content ranged from 6.9% (induced mutant Wt 95497) to 14.1% (Polish cultivar Wt 95420 and the landrace Wt 95212 from Jordan). From a dietetic point of view, oil quality is more important than oil quantity in lupin seeds. On average the fatty acid (FA) in examined accessions ranked in following order of abundance: oleic acid (C_18:1) > linoleic acid (C_18:2) > linolenic acid (C_18:3) > palmitic acid (C_16:0) > eicosenoic acid (C_20:1) > stearic acid (C_18:0) ≈ erucic acid (C_22:1). In respect to unsaturated fatty acid (UFA), monounsaturated oleic acid in each of estimated classes of accessions was predominant and most abundant (55.7%) in broad range of minimum–maximum values from 41.2 to 66.2%. The second examined monounsaturated fatty acid was erucic acid (1.74%) found in seeds of almost all studied accessions. An exception were four accessions defined similarly to rapeseeds as “zero erucic” forms. In seeds of few accessions a content of erucic acid exceeded 3%. Among polyunsaturated fatty acids linoleic FA (ω?6) dominated followed by linolenic FA (ω?3). Both FA were in the range 13.7–33.2% and 5.6–12.8% with mean values on the level 19.6 and 10.1%, respectively. As a consequence, the examined white lupin seeds showed a very favourable ω?3/ω?6 FA ratio (0.51), ranging from 0.21 to 0.87, much higher than that of most vegetable oils. Fat content was positively correlated with stearic and oleic fatty acids and negatively with palmitic, linoleic, linolenic and erucic acid.     

花生种子自然老化对品质及发芽的影响

为解析花生种子自然老化过程中品质及发芽特性的变化特征,本研究以6个花生品种(系)为试材,通过测定种子发芽率、发芽势、氯化三苯基四氮唑(TTC)还原量、电导率等指标对老化花生种子的品质和发芽活力进行综合评价。结果表明,随着种子老化程度加深,不同品种(系)花生种子的5个发芽指标(发芽率、发芽势、发芽指数、活力指数和生长量)均表现为显著下降趋势(P<0.05);花生种子的活力指数与TTC还原量呈相同的下降趋势,而电导率则呈上升趋势;除了亚油酸以外,其余4个花生品质指标,包括油酸、油亚比(O/L)含油量和粗蛋白,总体呈下降趋势,自然老化对花生品质及发芽特性均产生负向影响。本研究通过对自然老化种子中多个指标进行评价,为确定和探究不同花生品种的存储条件及代谢途径奠定一定的理论基础。     

EMS诱变花生珍珠红1号创制优良新种质

为创制花生优良新种质,以花生品种珍珠红1号的干种子为材料,采用浸泡法开展甲基磺酸乙酯(EMS)诱变研究。结果表明,以半致死剂量为选择标准,适宜诱变条件为0.8% EMS处理10 h;筛选获得9个优良M₅突变系,其中4个表现出产量高、品质优、综合性状优良等特点。上述4个M₅突变系干荚果产量较对照(珍珠红1号)增加10.93% ~ 26.78%,出仁率均高于对照;在品质方面,诱珍珠红1号2Ⅱ/19油酸含量为56.68%、油酸/亚油酸比值(O/L)为1.92,分别较对照提高8.44个百分点和0.57;诱珍珠红1号2Ⅲ/8亚油酸含量为39.05%,较对照提高3.28个百分点;诱珍珠红1号2Ⅲ/10粗脂肪含量为54.52%,较对照提高1.50个百分点;诱珍珠红1号3Ⅰ/8油酸含量为53.70%、O/L为1.71,分别较对照提高5.46个百分点和0.36。ISSR分子标记结果表明,9个优良M₄突变系与珍珠红1号在分子水平上均存在明显差异,突变系之间在分子水平上也存在明显差异。本研究结果为花生遗传改良和功能基因研究提供了优良的新种质,为花生EMS诱变育种研究提供了参考。     

花生根和荚果对外源钙的吸收特性研究

为了明确花生根和荚果对外源钙的吸收特性,本研究选取对钙敏感性不同的豫花37和豫花23为试材,利用自主研发的花生根果分区培养装置开展试验,设置不施钙(CK)、根区施0.20 g·kg^-1CaO(RL)、根区施0.80 g·kg^-1 CaO(RH)、荚果区施0.20 g·kg^-1CaO(PL)、荚果区施0.80 g·kg^-1 CaO(PH)共5个处理,探究根区和荚果区不同外源钙处理对土壤钙含量、花生生长发育及产质量、钙吸收积累分配特征的影响。结果表明,饱果成熟期,同一基因型花生根区施钙土壤钙含量低于荚果区相同施钙量处理,且以酸溶态钙为主,占土壤全钙的37.97%~64.52%;与根区施钙相比,荚果区施相同量的外源钙提高了花生的饱果数、出仁率和荚果产量,降低了籽仁可溶性糖含量,增加了油酸/亚油酸比值(O/L)和粗蛋白、粗脂肪、蛋氨酸、赖氨酸的含量;根区施钙花生根茎叶的吸钙量占花生植株总吸钙量的87.39%~91.11%,果壳和籽仁占8.89%~12.61%,荚果区施钙花生根茎叶占74.10%~84.85%,果壳和籽仁占15.15%~25.90%;与根区施钙相比,荚果区施钙显著提高了钙利用效率,豫花37荚果和籽仁钙利用效率分别提高了42.35%~49.28%和37.73%~43.89%,豫花23分别提高了32.43%~46.17%和21.05%~47.09%。总体来看,荚果区施钙较根区施钙显著提高了花生产质量和钙的利用效率。本研究结果为指导花生钙肥施用提供了理论依据。     

Assessment of oil content and fatty acid composition variability in two economically important Hibiscus species

The Hibiscus genus encompasses more than 300 species, but kenaf (Hibiscus cannabinus L.) and roselle (Hibiscus sabdariffa L.) are the two most economically important species within the genus. Seeds from these two Hibiscus species contain a relatively high amount of oil with two unusual fatty acids: dihydrosterculic and vernolic acids. The fatty acid composition in the oil can directly affect oil quality and its utilization. However, the variability in oil content and fatty acid composition for these two species is unclear. For these two species, 329 available accessions were acquired from the USDA germplasm collection. Their oil content and fatty acid composition were determined by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Using NMR and GC analyses, we found that Hibiscus seeds on average contained 18% oil and seed oil was composed of six major fatty acids (each >1%) and seven minor fatty acids (each <1%). Hibiscus cannabinus seeds contained significantly higher amounts of oil (18.14%), palmitic (20.75%), oleic (28.91%), vernolic acids (VA, 4.16%), and significantly lower amounts of stearic (3.96%), linoleic (39.49%), and dihydrosterculic acids (DHSA, 1.08%) than H. sabdariffa seeds (17.35%, 18.52%, 25.16%, 3.52%, 4.31%, 44.72%, and 1.57%, respectively). For edible oils, a higher oleic/linoleic (O/L) ratio and lower level of DHSA are preferred, and for industrial oils a high level of VA is preferred. Our results indicate that seeds from H. cannabinus may be of higher quality than H. sabdariffa seeds for these reasons. Significant variability in oil content and major fatty acids was also detected within both species. The variability in oil content and fatty acid composition revealed from this study will be useful for exploring seed utilization and developing new cultivars in these Hibiscus species.     

不同生育期水分亏缺耦合施氮量对花生光合特性和品质的影响

为探究不同生育期水分亏缺和施氮量对花生光合特性、产量及品质的影响，于2020和2021年设置测坑裂区试验，研究充分灌溉（IF，灌水下限为田间持水率的70%～75%）和调亏灌溉（IRD，花针期和饱果期控水下限均为田间持水量的55%～60%）下，施氮量（0（N0）、50（N50）、100（N100））kg/hm2）对花生光合速率、蒸腾速率、产量及品质的影响。研究结果表明，与充分灌溉相比，花针期调亏灌溉降低了花生叶片光合速率和蒸腾速率；结荚期复水后，由于补偿效应，调亏灌溉处理的光合速率和蒸腾速率均高于充分灌溉。调亏灌溉耦合100 kg/hm2氮肥处理（IRDN100）显著提高了花针期和结荚期的光合速率和蒸腾速率（P?0.05），且花生产量最高，较传统水氮处理（IFN100）2 a平均提高了13.4%（P?0.05）。与传统水氮处理相比，IRDN100处理生产的花生具有相对较高的蛋白质、油脂、油酸、亚油酸含量及油亚比，即出油量和储存品质均较好。因此，IRDN100处理不仅能节水增产，还能改善花生品质，可为干旱半干旱地区实现花生节水提质增效生产目标提供理论参考。     

EMS诱发大豆脂肪酸组成优良突变的研究

本文采用0.2％甲烷磺酸乙酯(EMS)溶液(pH7)处理大豆稳定系LF81-9903和F_1(合交77-153×哈80-3249)种子,研究大豆油主要脂肪酸的变异,以探求改善大豆油品质的有效技术方法。试验表明,经EMS处理后,大豆油中脂肪酸含量发生遗传改变,其方差明显提高,较未处理对照提高1.2～6倍。广义遗传力、遗传进度发生一定程度的变化。出现一些亚麻酸含量明显下降、亚油酸含量降低较少甚至增加的优良突变体,如518-1,643-3等。现正进行抗病性、丰产性的培育。0.2％EMS对诱发大豆脂肪酸有益突变是有效的。     

Screening of the entire USDA castor germplasm collection for oil content and fatty acid composition for optimum biodiesel production

Castor has tremendous potential as a feedstock for biodiesel production. The oil content and fatty acid composition in castor seed are important factors determining the price for production and affecting the key fuel properties of biodiesel. There are 1033 available castor accessions collected or donated from 48 countries worldwide in the USDA germplasm collection. The entire castor collection was screened for oil content and fatty acid composition by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Castor seeds on the average contain 48.2% oil with significant variability ranging from 37.2 to 60.6%. Methyl esters were prepared from castor seed by alkaline transmethylation. GC analysis of methyl esters confirmed that castor oil was composed primarily of eight fatty acids: 1.48% palmitic (C16:0), 1.58% stearic (C18:0), 4.41% oleic (C18:1), 6.42% linoleic (C18:2), 0.68% linolenic (C18:3), 0.45% gadoleic (C20:1), 84.51% ricinoleic (C18:1-1OH), and 0.47% dihydroxystearic (C18:0-2OH) acids. Significant variability in fatty acid composition was detected among castor accessions. Ricinoleic acid (RA) was positively correlated with dihydroxystearic acid (DHSA) but highly negatively correlated with the five other fatty acids except linolenic acid. The results for oil content and fatty acid composition obtained from this study will be useful for end-users to explore castor germplasm for biodiesel production.     

Variation in seed oil composition of species from the genera Barbarea and Lepidium

The seed oil composition and content in a number of accessions from species of the genera Barbarea and Lepidium were analysed. The oil from most accessions of B. verna contained more than 50% erucic acid, while the oil from B. vulgaris contained ～ 30% erucic acid, and 22% each of oleic and linoleic acid. The oil from B. intermedia resembled that of B. verna. The oil content was ～ 30% in all three species. The oil composition of L. campestre and L. heterophyllum is ～ 35% linolenic acid and 23% erucic acid. Other Lepidium species had up to 47% linolenic acid in the oil. The oil content of L. campestre and L. heterophylhim was just below 20%, but other species had more than 30% oil in their seeds. The variation in oil composition found within and between species is considered sufficient for the breeding of valuable oil qualities in both genera.