Variations in seed size and seed mass related to tree growth over 5 years for 23 provenances of Quercus acutissima from across China

The origin of a seed strongly impacts its traits, and both origin and seed traits influence seed germination and seedling development. However, in many instances, this effect on the seedling does not persist into adulthood, and little is known about how seed traits and original environment affect seedling/tree growth over time. In this study, seed size, seed mass, seedling/tree growth and origins were collected and determined for 23 provenances of Quercus acutissima from across China. Origin variables correlated well with seed size and seed mass. In stepwise multiple regressions, a longitudinal aridity index explained 49.2-68.7% of the total variation in seed size and mass, while only seed width was correlated with seedling/tree height (H) and diameter at the ground (D) from seed traits and origins. The total variance in H and D explained by the models decreased over time, for example, the R 2 value of the models for H declined from 0.477 in the first year to 0.224 in the fourth year; no models was significant in the fifth year. These results indicate that seed size, regulated by the longitudinal aridity index strongly impacted seedling and tree growth, but the strength of the influence decreased over time, and disappeared after 4 years.

Plant life form determines spatiotemporal variability and climate response of plant seed rain in subtropical forests

Spatiotemporal variation of seed rain reflects the response of plants in terms of their reproductive strategy to environmental gradients.In this study,we collected seeds from four sites in the Dalaoling Nature Reserve,Hubei Province,China,between 2011 and 2014,measured seed output and seed mass as seed rain traits,and compared their interannual and elevational variation.Then,we ran phylogenetic generalized mixed linear models(PGLMMs) to explore the effects of temperature and precipitation as well as interspecific differences on seed rain,and fitted the best regression models for seed rain vs.weather of canopy and understory species.The results showed no correlation between values of seed output and seed mass.However,the variation of the two traits showed significantly positive correlation.Seed output of canopy species generally decreased with increasing elevation,and showed significant interannual difference;however,seed output of understory species and seed mass for both canopy and understory species did not show consistency tends along elevational or in interannual variation.Seed output was significantly affected by temperature and precipitation,while seed mass mainly varied due to interspecific differences.Weather explained more the variation of the seed output of canopy species than that of understory species,with R^(2) values of 43.0%and 29.9%,respectively.These results suggested that canopy plants contributed more to the reproductive dynamics of the whole communities,and the canopy's buffer effect on the underground weakened the response of understory plants to weather variation in terms of their reproductive strategy.

论新疆三种药用甘草种子油化学成分GS-MASS 分析结果及其异同点

本文采用溶剂提取法提取并甲酯化,然后用气相色谱-质谱对新疆三种药用甘草种子油化学成分及组成进行定性定量分析。结果表明,它们的主要成分以不饱和脂肪酸为主,其中含量最多的是亚油酸,含量顺序为:光果甘草(GGL)=46.25%>乌拉尔甘草(GUF)=30.18%>胀果甘草(GIB)=24.2%;亚麻酸含量顺序为:GUF=43.2%>GIB=42.14%>GGL=34.40%;花生三烯酸的含量顺序为:GGL=33.58%>GUF=24.65%>GIB=24.26%。气相色谱共检测出65个峰,共分离出64种化合物,鉴定了63种化合物,其中脂肪酸是20种,其他都是挥发性成分,但是脂肪酸的成分占总峰面积的95%~96%。三种药用甘草种子油的总化合物中含量不相似24种,在两种甘草之间相似的化合物达32种。通过气相色谱-质谱法定性和定量分析,采用面积归一化法确定各组分的相对含量,为新疆甘草的进一步开发利用提供一定的理论基础。

Seeds as a Source of Carbon, Nitrogen, and Phosphorus for Seedling Establishment in Temperate Regions: A Synthesis

Seeds are a source of organic (carbon, C) and mineral (nitrogen, N and phosphorus, P) nutrients for the growing seedling. There is much information on seed mass and N and P contents, and the relationship between these and seedling mass. Within the world’s temperate regions, these collectively show that N and P concentrations remain constant or rise with increase in seed mass and that seeds are larger and more nutrient-enriched in poorer soils. Seed N and P were more important than seed C in accounting for seedling mass in 85% of studies we assessed. In nutrient- and water-limited environments that are not light-limited, large seeds routinely provision the seedling with N and P that enhance C-fixation and thus general growth in the first wet season. This system is so efficient that growth response to soil nutrients may be negligible in first-year seedlings arising from seeds > 15 mg mass, N content > 5 mg and P content > 1.6 mg. The elongating taproot system absorbs nutrients and maintains water uptake as soil water retreats, enhancing the chances of survival in the first dry season. We outline an interpretative scenario for the special role of large seeds (>15 mg) in nutrient- and water-limited environments that recognizes the critical role of N and P for photosynthesis in ensuring sufficient C-supply to the rapidly descending roots for effective drought-avoidance by the young plant.

Response Surface Optimization of Nigella glandulifera Freyn Seed Oil Yield by Supercritical Carbon Dioxide Extraction

Supercritical carbon dioxide （SC-CO2） extraction was employed to extract oil from Nigella glandulifera Freyn seed in this study. Response surface methodology （RSM） was applied to evaluate the effects of the process parameters （pressure, temperature, and CO2 flow rate） on oil yield of N. glandulifera seed. A Box-Behnken design was used to optimize the extraction parameters. The analysis of variance indicated that the linear coefficients of pressure and CO2 flow rate, the quadratic term coefficients of pressure and temperature and the interactions between pressure and temperature, as well as temperature and CO2 flow rate, had significant effects on the oil yield （P〈0.05）. The optimal conditions to obtain the maximum oil yield from N. glandulifera seed were pressure 30.84 MPa, temperature 40.57°C, and CO2 flow rate 22.00 L h-1. Under these optimal conditions, the yield of oil was predicted to be 38.19%. The validation experiment results agreed with the predicted values. The fatty acid composition of N. glandulifera seed oil extracted using SC-CO2 was compared with that of oil obtained by Soxhlet method. The results showed that the fatty acid compositions of oil extracted by the two methods were similar. Identification of oil compounds with gas chromatography-mass spectrometry （GC-MS） showed that the contents of unsaturated fatty acids linoleic acid （48.30%）, oleic acid （22.28%） and saturated fatty acids palmitic acid （16.65%）, stearic acid （4.17%） were the most abundant fatty acids in seed oil from N. glandulifera.

Comparison of Five Selection Procedures for Seed Coat and Hilum Color in Interspecific Crossing of Soybeans

Five selection procedures for seed coat and hilum color were studied with F4 progenies in two interspecific crossing of soybeans. The seed coat and hilum color indicated that pedigree, 5% and 10% mass selection method were equally successful, and were better than picking-pod and 25% mass selection in cross S17. However, no significant differences in seed coat and hilum color were found in cross G18.

不同采收期及后熟期对野生西瓜种子质量的影响

为解决野生西瓜制种时间较长的问题,以野生西瓜砧木‘野壮101’为材料,通过研究果实不同发育时间及种子后熟时间的发芽率等种子质量相关性状,分析采收期及后熟期对野生西瓜砧木种子质量的影响。结果表明,果实采收期及后熟时间均影响种子质量及外观。当果实发育60 d、果实采收后种子后熟10 d时,野生西瓜砧木种子发芽率、发芽势、千粒质量均最高,分别为92%、90%、252 g。

气候变化对暴马丁香种子质量的影响研究

在山西省暴马丁香的主要分布区内,选择13个种源的67棵单株,进行种子质量测定,并通过遥感数据和已有数据库获取与气候变化密切相关的环境因子数值,运用线性混合效应模型研究了环境因子对暴马丁香种子质量的影响。结果表明,暴马丁香种子质量为13.6 mg±2.7 mg,其变异系数CV为34.3±9.0。暴马丁香种子质量随着近地面CO_(2)浓度和土壤N含量增加而增加,随着年平均降水量增加和土壤P含量减少而增加,随着土壤N含量增加和土壤P含量减少而增加。暴马丁香种子质量CV随着近地面CO_(2)浓度提高而增加,随着近地面CO_(2)浓度增加和年平均降水量减少而增加。从影响程度来看,N和P的交互效应对种子质量影响最大,其次是CO_(2)和N的交互效应以及AP和P的交互效应。CO_(2)以及CO_(2)和AP的交互效应对种子质量CV的影响相似。

顶空固相微萃取-气相色谱质谱联用测定辣木籽中挥发性成分

该文建立顶空固相微萃取-气相色谱质谱联用(headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)对辣木籽中挥发性成分的萃取检测方法。试验优化萃取条件和GC-MS检测条件,分析3个品种(印度、非洲和中国云南)10个不同地区辣木籽中挥发性成分。结果表明,在最佳萃取条件为采用100μm PDMS萃取头、萃取温度66℃、萃取时间30 min、转速320 r/min,GC-MS共检出10种辣木籽中58种主要挥发性成分,以醇、酮、醛、酯、酸类化合物为主,印度品种辣木籽特有成分为月桂醛,非洲品种辣木籽特有成分为丁香酚,中国云南改良品种辣木籽特有成分为2-甲基异茨醇和乙酸己酯。

辣木籽凝乳酶在水牛乳干酪制备中应用及产血管紧张素转化酶抑制肽分析

本实验以辣木籽凝乳酶和水牛乳为原料,以干酪感官评分和蛋白水解度为指标优化干酪加工工艺,解析其水溶性肽组成,进一步挖掘具有血管紧张素转化酶(angiotensin converting enzyme,ACE)抑制活性的功能性肽及其潜在分子作用机制。结果表明,干酪最佳工艺参数为凝乳pH 5.56、凝乳酶添加量0.14%、凝乳时间32 min、热烫温度80℃,此条件下干酪水解度为12.56%,所得干酪质地均匀有弹性、口感柔软细腻、色泽均匀有光泽且香味浓郁;基于液相色谱-串联质谱在干酪中检出1600种分子质量小于3 k Da的蛋白肽段,活性预测表明613条肽段具有较好的生物活性,主要来源于β-酪蛋白和α_(S1)-酪蛋白,其中具有ACE抑制活性的肽段占比达到37.29%;通过活性肽数据库比对结合生物信息学手段筛选出兼具多重活性的已知ACE抑制肽和新型ACE抑制肽各4条,分子对接分析进一步表明4条新型肽段均可以与ACE有效结合,其中2条肽段FGGL、FSPL分别与S2活性口袋结合紧密而显示较强的ACE抑制活性。本研究可为新型植物凝乳酶资源及特色水牛乳干酪的开发利用提供科学依据。

施氮量和收获时间对羊草种子产量的影响

羊草(Leymus chinensis)种植过程中常见发芽率低、分蘖低,甚至颗粒无收的现象,增施氮肥能在一定程度上改善这种情况,收获时间是影响种子产量的关键因素。为此,研究施氮量[不施氮、150、300 kg·(hm^(2)·a)^(-1)]和收获时间(盛花期后25、30、35、40、45 d)对羊草种子产量的影响,以明确新疆地区羊草的施氮量和最佳收获时间。结果表明:1)施氮量和收获时间对羊草种子发芽率、产量及其构成因素产生显著影响。盛花期后35 d收获与40、45 d收获相比,羊草种子发芽率、产量及产量构成因素没有显著差异。盛花期后25 d收获,150 kg·(hm^(2)·a)^(-1)处理的种子发芽率比不施氮和300 kg·(hm^(2)·a)^(-1)处理分别增加了31.25%和12.51%。2)施氮量显著提高了羊草各部位的全氮含量,收获时间对羊草各部位全氮含量并没有显著影响,羊草各部位全磷含量随着施氮量的增加呈现先增加后降低的趋势。研究结果显示,在新疆羊草种子生产时,适宜的施氮量是150 kg·(hm^(2)·a)^(-1),最佳收获时间为盛花期后35 d。

气相色谱-质谱法测定牡丹籽油中的总甾醇含量

采用气相色谱-质谱法测定牡丹籽油中β-谷甾醇、麦角甾醇、菜油甾醇、菜籽甾醇的含量,结果显示麦角甾醇、菜籽甾醇、菜油甾醇、β-谷甾醇在1~50μg·m L^(-1)线性良好,相关系数≥0.99744,回收率为75.6%~96.1%,RSD为0.39%~3.87%。牡丹籽油中总甾醇含量从高到低依次为β-谷甾醇、麦角甾醇、菜油甾醇,其中β-谷甾醇的平均含量为27.44 g·kg^(-1)。通过对牡丹籽油中甾醇含量进行测定和分析,可为相关企业挖掘牡丹籽油特色功能、发现特色指标提供数据支撑。

油茶籽功能性成分的提取、鉴定及其活性评价

油茶籽广泛种植于我国南方地区,是食用植物油的重要原料。为了探明其有效成分,文章首先通过气相色谱-质谱法对其挥发性成分进行分析。其中,顺-十八碳烯酸、n-十六酸、7-丁基苯并[a]蒽等成分的含量较高,并发现生育酚、角鲨烯等活性成分。随后采用超声强化溶剂提取法对油茶籽中的功能性因子进行提取,并探究了超声温度、pH、乙醇浓度、料液比对活性成分提取率的影响。4个因素对酚类物质提取率的影响次序为pH>超声温度>乙醇浓度>料液比,且超声温度和乙醇浓度的交互作用最强。通过响应面优化后,得到总酚的最佳提取工艺条件为超声温度45℃、乙醇浓度40%、料液比1∶10、pH 4。抗氧化活性实验结果表明,其半抑制浓度IC_(50)为39.72 mg/mL,其在抗炎、抗肿瘤领域的功效值得进一步研究。

微波处理对不同产地葵花籽品质的影响

比较微波处理对不同产地葵花籽品质的影响,探究烘烤后葵花籽的品质差异。以新疆、甘肃、巴彦淖尔、乌蒙四个产地的葵花籽为原料,分析微波处理后其营养成分和挥发性有机化合物变化。结果表明,乌蒙产地葵花籽样品的蛋白质含量最高;巴彦淖尔产地样品的脂肪酸组成接近1∶1∶1。含油率方面,新疆产地葵花籽样品中含量最高。基于顶空固相微萃取-气相色谱-质谱技术,样品共检测到66种挥发性风味物质,包括醛类、吡嗪类、醛类、酯类等。通过主成分分析,新疆和巴彦淖尔产地的葵花籽挥发性风味物质组成相似,与其他产地的葵花籽差别较大。不同产地的烘烤葵花籽香气成分存在明显差异,其中吡嗪类化合物更为丰富含有8种,赋予葵花籽浓郁的坚果味。本研究为葵花籽加工的质量控制及产地溯源提供一定的理论依据。

青藏高原东部4科植物种子大小和比叶面积随海拔和生境的变异

种子大小和比叶面积分别是种子植物的繁殖性状和营养性状之一,也是衡量植物功能的2个重要参考。本研究测量4个青藏高原东部常见科(虎耳草科Saxifragaceae;龙胆科Gentianaceae;毛茛科Ranunculaceae;石竹科Caryophyllaceae)的63种植物的种子大小和比叶面积,分析2种性状之间的相关性,并研究海拔和生境因子对其的影响。结果表明,1)种子大小和比叶面积有边际明显的负相关关系(P=0.066);2)无论整体上还是在科内,青藏高原东部植物种子大小与海拔和生境均不相关(P>0.05);3)区域内植物比叶面积随海拔的升高而显著减小;在科内,海拔对毛茛科、龙胆科植物的比叶面积影响显著,而石竹科、虎耳草科植物的比叶面积与海拔不相关;4)草地中植物比叶面积最小,林下最大;在草地中比叶面积随海拔的升高而显著减小,其他生境下海拔对比叶面积没有影响。研究结果反映了青藏高原东部植物对高寒环境不同的响应和适应。

古尔班通古特沙漠植物种子大小变异的空间格局

在古尔班通古特沙漠70个固定样地中采集了87种植物种子,通过测量种子百粒重,分析了种子大小在不同分类群中的变异规律,并调查了样地中不同类型种子总数目的空间格局。结果发现:1)古尔班通古特沙漠植物种子大小可分为:A(0.1—1 mg)、B(1—10 mg)、C(10—100 mg)、D(100—1000 mg)、E(1000—5000 mg)5种类型。拥有不同类型物种数量差异较大,其中D型种子物种最多,含41种占总物种数目的 47.1%,其次C型种子30种占总物种数目的 34.5%,E型种子占总物种数的13.8%,B型种子总物种数的3.5%,A型种子占总物种数的1.1%。沙漠植物中中等种子大小物种占多数,与以色列特拉维夫以北的Poleg自然保护区地中海沿岸沙漠地区相似。由于本地属、种为地中海区、西亚至中亚分布,所以认为本沙漠种子大小主要受系统演化影响。2)科间种子大小存在极显著差异,百粒重最大科是蓼科(29315 mg)、最小的是列当科(0.3 mg)。藜科,菊科,紫草科的属间种子大小差异显著。3)生活型间种子大小差异显著,种子大小从大到小排序为:灌木>类短命植物>多年生草本>短命植物>半灌木>1年生草本。4)种子大小与物种相对分布频度相关性不显著,但将相对分布频度小于1.4%的环境特化物种去除后,种子大小与物种相对分布频度呈指数型极显著负相关。5)B型、C型、D型三类种子在样地中的总数目随海拔、经度和降水的增加而极显著增加,随纬度的增加而极显著降低,E型种子则与之相反。表明古尔班通古特沙漠未来随着降水的增加,B型、C型、D型种子的植物优势性逐渐增加,而E型种子的灌木类等物种优势性逐渐减少,注意加以保护。

科尔沁沙地124种天然植物粘液繁殖体的甄别

用粘沙法对科尔沁沙地西部124种天然植物进行了粘液繁殖体甄别。结果表明:(1)在124种植物中,有13种植物包括冷蒿(Artemisiafrigida)、万年蒿(A.gmelinii)、差不嘎蒿(A.halodendron)、野艾蒿(A.lavan-dulaefolia)、大籽蒿(A.sieversiana)、黄蒿(A.scoparia)、乌丹蒿(A.wudanica)、画眉(Eragrostispilosa)、小画眉(E.poaeoides)、百里香(Thymusmongolicus)、平车前(Plantagodepressa)、盐生车前(Plantagomaritima)、野亚麻(Linumstelleroides)的种子分泌粘液,占所有被测植物的10.5%;(2)综合浇水2mm和水浸20min两种处理结果发现,盐生车前、平车前、乌丹蒿、冷蒿、百里香粘液(粘沙)繁殖体比例很高,万年蒿、黄蒿、野艾蒿粘液繁殖体比例相对低;(3)综合浇水2mm和水浸20min处理结果发现,分泌粘液粘沙后重量变化较大的植物包括画眉、小画眉、盐生车前、乌丹蒿、万年蒿;(4)将水浸20min与浇水20mm处理的结果进行平均,得到的粘沙种子总粘沙量由小到大的顺序是:黄蒿<野艾蒿<万年蒿<小画眉<画眉<冷蒿<差不嘎蒿<大籽蒿<百里香<野亚麻<平车前<乌丹蒿<盐生车前;(5)全部13种有粘液繁殖体植物的种子均小,单粒重小于1mg;(6)无论对水浸20min,还是浇水20mm处理,粘沙种子粘沙量与未粘沙种子重量正相关,即种子越大,粘沙量越大;(7)蒿属植物占具有粘液繁殖体植物的比例较大,供试的7种植物均有种子分泌粘液,但在粘沙种子重量增加量、粘沙种子对未粘沙种子的重量倍数、粘沙种子百分数等方面表现物种间差异;(8)蒿属植物分泌粘液是其适应流沙的属性之一。

小型啮齿动物对小兴安岭5种林木种子扩散的影响

在小兴安岭地区研究了林鼠对胡桃楸(Juglans mandshurica)、毛榛(Corylus mandshurica)、平榛(Corylus heterophylla)、红松(Pinus koraiensis)、樱桃(Cerasus pseudocerasus)5种具有不同特征的林木种子扩散的影响。结果表明:大林姬鼠(Apodemus speciosus)、棕背鼠平(Clethrionomys rufocanus)和花鼠(Eutamias sibiricus)是3种主要的种子捕食者和扩散者。5种种子的扩散速度显著不同,体积最大且种皮较厚的胡桃楸种子原地剩余的比例最大(65%),体积最小且种皮最薄的樱桃原地剩余的比例较高(39%)。种子被原地取食的比例与种子收益(种仁质量)间呈现显著负相关。红松种子被分散贮藏的比例最大(23%),而樱桃种子很少被分散贮藏(1%),胡桃楸以及2种榛子的埋藏率明显低于红松。5种种子的平均扩散距离差异显著,且与单粒种子收益间呈显著正相关关系。研究表明,任何单一种子性状都不能完全解释种子的扩散模式,但单粒种子的收益是影响种子命运和扩散距离的关键因素。

干热河谷植物叶片,树高和种子功能性状比较

植物功能性状(plant functional trait)是近年来生态学研究的热点。以云南怒江和澜沧江干热河谷36种木本植物为研究对象,选取比叶面积(SLA)、植株高(H)和种子干重(SM)3个功能性状,研究它们的相互关系,比较其在河谷间、河谷内的差异。结果表明:1)两个河谷内36种木本植物的以上3种功能性状间没有显著的相关性(P值分别为0.8739,0.5763,0.5517);2)河谷间的比叶面积存在显著差异(P=0.02944),植株高和种子干重无显著差异(P分别为0.4070,0.8867);3)两个河谷内木本植物功能性状中,种子干重差异最大,植株高次之,比叶面积最小。

南北样带温带区栎属树种幼苗功能性状的变异研究

植物功能性状由生境条件和遗传因素共同决定,田间控制实验能够揭示植物功能性状在种内和种间的变异程度。采集南北样带温带区8个地点6种栎属树种的种子,通过田间栽培试验,以均一环境下1年生幼苗为对象,研究比较种内及种间比叶重、单位叶面积光合速率、单位叶重量光合速率、总干物质含量和根冠比5种功能性状的变化差异,并且分析幼苗功能性状与种子性状的关系。结果发现:栎属树种种间幼苗的功能性状变异系数高于种内,并且种内功能性状的差异较小,种间差异性较大,而比叶重和叶片光合速率无论在种间还是种内,其变异率都较小;总干物质量和根冠比与种子质量显著相关,随种子质量增加幼苗的总干物质量和根冠比呈现增加的趋势,比叶重和叶片光合速率与种子质量的相关性较小。