小油桐籽提取液对作物种子萌发及幼苗生长的影响

研究不同浓度的小油桐籽水提取液及酒精提取液对‘贵杂110号’油菜、‘卓越’黑麦草及‘早麦10号’小麦种子萌发及幼苗生长的影响。结果表明,小油桐籽水提取液对3种作物种子发芽率、幼苗的芽长及根长有抑制作用,且随浓度提高抑制作用增强;酒精提取液对黑麦草与小麦的种子发芽、幼苗芽和根的生长有抑制作用,但特定浓度可促进油菜幼苗芽的生长。     

优质鲜食黄肉猕猴桃新品种‘金圆’的选育及特性分析

‘金圆’是以种间杂交品种‘金艳’（Actinidia chinensis×A.eriantha）为母本、中华猕猴桃（A.chinensis Planch.）为父本,从回交F₁代群体中选育出的中熟黄肉猕猴桃新品种。通过对‘金圆’植物学性状、特异性、营养成分、贮藏性等进行研究,结果显示：‘金圆’果实为短圆形,单果重80~100 g,软熟时果肉橙黄色,质细味浓;‘金圆’的花瓣数和花丝数与母本‘金艳’接近,花冠直径和柱头数较‘金艳’分别增大了9.31%和52%,而花柄长度比‘金艳’短16.75%;萌芽率和果枝率略低于‘金艳’,但比‘海沃德’高出55.26%和43.33%;‘金圆’的可溶性固形物、总糖和可滴定酸含量与‘金艳’相当,但维生素C含量比‘金艳’高4.63%,是‘海沃德’的2.2倍;‘金圆’矿质元素含量丰富,P和K含量分别比‘金艳’高30.86%和22.53%,Mg含量比‘海沃德’高24.86%;‘金圆’的总氨基酸含量丰富（8 mg/g）,E/N和E/T值均高于‘金艳’和‘海沃德’,更接近于理想模式;‘金圆’在低温下（1~2℃,相对湿度90%~95%）贮藏150 d时,好果率在80%以上,200 d后,好果率仍有65%,贮藏性略低于‘金艳’,但显著高于‘海沃德’。利用Geo7-223分子标记扩增‘金圆’基因组得到3个条带,表明其与‘金艳’和‘金桃’在分子水平上具有一定差异。本研究表明‘金圆’具有良好的农艺性状和品质特性。     

多元统计分析方法在万寿菊品种抗旱性评价中的应用

利用主成分分析法、隶属函数法和聚类分析法,对9个万寿菊品种16个生理指标的抗旱性进行综合评价.结果表明： 不同品种万寿菊的16个生理指标变化程度不同,其中脯氨酸(Pro)、H₂O₂和抗坏血酸过氧化物酶(APX)对干旱胁迫的敏感性最大,而且部分抗旱系数之间显著相关;4个主因子代表16个生理指标抗旱性88.6%的数据信息,‘珍妮’和‘金门’、‘鸿运’、‘珍妮’、‘拳王’分别在4个主因子上的抗旱性最强;9个品种的抗旱性综合评价值大小为：‘珍妮’>‘金门’>‘鸿运’>‘拳王’>‘巨人’>‘大英雄’>‘小英雄’>‘迪阿哥’>‘发现’;聚类分析将9个品种分为3类,其中‘金门’、‘珍妮’、‘鸿运’和‘拳王’属于抗旱品种.     

不同定植期和摘心方案下5个品种(系)茶用菊生长和产量性状的变化

为了比较5个茶用菊新品种(系)的产量水平,并筛选出获得高产的定植期和摘心方案,以 ‘苏菊10号’、‘苏菊12号’、‘苏菊13号’、‘CH1-44’、‘CH5-13’ 为试材,采用三因素裂区试验设计,主区为早、中、晚3个定植期,裂区为5个新品种(系),裂裂区为4种摘心方案,比较不同栽培措施下植株生长和产量的差异.结果表明: 5个新品种(系)中,‘CH5-13’和‘苏菊13号’产量相对较高,‘CH1-44’和‘苏菊10号’产量次之,‘苏菊12号’产量最低;5月27日中期定植、二次摘心措施下5个新品种(系)的株高、冠幅、单株花数、花径、单花鲜质量、单株产量和单位面积产量均显著优于其他处理,较5月7日和6月13日定植分别提高16.0%和19.0%、18.0%和22.8%、36.7%和42.2%、11.1%和2.3%、13.0%和4.0%、47.8%和36.6%、48.5%和36.7%.随着摘心时间的推迟,株高显著降低,二次摘心株高较不摘心降低50.2%;二次摘心处理的冠幅、单株花数、单花鲜质量、单株产量和单位面积产量最高,较不摘心依次提高17.0%、29.1%、5.5%、34.0%和34.8%.品种(系)、定植期、摘心方案3个因素对茶用菊生长性状和产量影响作用的大小依次为:定植期>品种>摘心.     

银杏胚乳淀粉体的积累规律和发生特性

以银杏（Ginkgo biloba L.）核用品种‘七星果’、‘马铃’和‘龙眼’不同发育天数的胚乳为材料,采用透射电镜和扫描电镜技术,对其胚乳细胞内淀粉体的积累规律和发生特性进行研究。结果显示：3种银杏胚乳形态差异显著,‘七星果’呈梭形、‘马铃’呈椭圆形、‘龙眼’呈卵圆形;3种银杏胚乳早期均为嫩绿色,后期为黄色;授粉后65~125 d是胚乳体积快速增长时期。淀粉体的积累规律为：在胚乳组织内,淀粉体由糊粉层-外胚乳-内胚乳逐渐积累;在单个胚乳细胞内,淀粉体由细胞壁边缘向内部逐渐充实。银杏淀粉质体起源于类叶绿体质体,淀粉粒最初在类叶绿体质体的内膜上发生。淀粉体通过出芽、缢缩以及出芽和缢缩同时进行的增殖方式产生新淀粉体,成熟淀粉体形态有圆形、椭圆形和不规则形,属于单粒淀粉。研究结果表明银杏淀粉体在胚乳组织内具有由外向内的空间积累规律,淀粉质体起源于类叶绿体质体并通过出芽、缢缩、出芽和缢缩同时存在的方式增殖。     

不同品种油甘子果实营养成分评价

为系统分析评价不同品种油甘子(Phyllanthus emblica)果实的营养品质,以‘赤皮’‘玻璃油甘’‘东坑甜’‘饼甜’‘六月白’和‘马蹄甜’6个品种油甘子果实为材料,测定7项营养成分含量,运用主成分分析法对果实营养成分含量进行分析评价。结果表明,各品种油甘子维生素C和还原糖含量均较高;维生素C与蛋白质呈显著正相关,还原糖与可溶性固形物呈显著正相关。通过主成分分析提取出3个主成分,认为‘赤皮’和‘玻璃油甘’2个品种可作为油甘子丰产林建设的优良栽培品种。     

盐胁迫对不同品种小白菜种子萌发特性的影响

采用5个小白菜(Brassica chinensis)品种(‘七宝青’、‘夏冬青’、‘四月慢’、‘南京中杆’和‘605’),用100 mmol/L NaCl对种子发芽作盐胁迫处理,从发芽势、发芽率、发芽指数、盐害指数、胚长和胚鲜重等指标比较了5个小白菜品种的抗盐性。结果表明,‘七宝青’种子的耐盐性优于其它品种。     

不同微型月季品种扦插生根效果综合评价

为了筛选易生根的优良微型月季品种,采用主成分分析、隶属函数和聚类分析方法,对7个微型月季品种扦插的7个根系形态指标进行综合评价。结果表明,微型月季品种之间的生根能力存在差异,7个根系形态指标用3个相互独立的综合指标代替,即第1主成分、第2主成分和第3主成分,7个微型月季品种扦插生根效果依次为：‘淑女’、 ‘红色恋人’、‘绝恋’、‘女儿红’、‘维纳斯’、‘春色’、‘灵感’,其中‘淑女’在种苗生产上采用常规扦插方法即可保证较高的插穗成活率。     

‘凤丹’生物量分配的季节动态及其受株龄和遮荫的影响

生物量分配动态研究对了解作物产量形成机制具有重要意义。‘凤丹’是以杨山牡丹（Paeonia ostii T.Hong et J.X.Zhang）为原种形成的新型木本油料作物,其产量形成机制尚不明确。本文采取破坏性取样策略,研究不同株龄‘凤丹’生物量分配的季节动态以及遮荫对产量的影响。结果显示,‘凤丹’生物量在果熟期达到最大值,总生物量随株龄增大而增加,但其增长速率趋势则相反。‘凤丹’根和茎的生物量分配在休眠期最大,而叶生物量分配最大值出现在果熟期;繁殖分配仅为3.24%~6.85%,但随株龄增大而增加（4年生果实生物量为（7.74 ±0.31）g/株,8年生果实生物量为（26.81 ±0.44）g/株）。‘凤丹’单株年同化总量为161.21~232.34 g,种子收获指数为2.71%~6.87%,收获指数与株龄呈正相关（R²=0.8178）。‘凤丹’营养生长和总生物量在遮荫条件下有所降低,但繁殖生物量和收获指数在30%遮阳处理中显著增加（种子增产3.66 g/株,产量提高389.36%）。本研究表明‘凤丹’年周期内的源与库结构呈动态变化,株龄对‘凤丹’的生物量分配及产量有明显效应,适度遮荫可提高‘凤丹’的产量。     

遮荫对彩叶植物矾根夏季适应性表型的影响

以彩叶植物矾根(Heuchera micrantha)‘蜜桃’(‘Georgia Peach’)、‘小珍珠’(‘Petite pearl fairy’)、‘花毯’ (‘Tapestry’)为材料,研究不同遮荫处理对矾根观赏特征、高温半致死温度以及成活率的影响。结果表明,在遮荫条件下,三个矾根品种株高增加、叶面积变大、花序变长、开花推迟,‘蜜桃’和‘小珍珠’花期延长,‘花毯’花期缩短。遮荫引起‘蜜桃’和‘小珍珠’叶绿素含量、类胡萝卜素含量显著上升,花色素苷含量明显下降,叶色由红、紫色向灰绿色转变,叶片彩化度下降;‘花毯’的叶绿素、类胡萝卜素和花青素含量均随遮荫度增加显著上升,其叶色由浅绿转为深绿,叶脉紫红色加重,彩化度提高,观赏性增强。随着遮荫度提高,三个矾根品种的高温半致死温度明显升高,成活率显著上升。相关性分析表明,三个矾根品种的成活率与最高气温、最大光强、气温、光强分别存在极显著负相关关系,与相对湿度以及该品种的高温半致死温度分别存在极显著正相关关系。多元逐步回归分析表明,高光强是引起‘蜜桃’成活率下降的关键因素,‘小珍珠’的成活率主要取决于高温半致死温度,‘花毯’的成活率主要受极端高温的影响。     

Effects of traditional Chinese medicine on immune responses in abalone, Haliotis discus hannai Ino

A traditional Chinese medicine (TCM) preparation was formulated from orange peel (Pericarpium Citri Reticulatae), hawthorn (Crataegus pinnatifida), astragalus (Astragalus membranaceus (Fisch.) Bunge), pilose asiabell root (Radix codonopsis), indigowoad root (Radix isatidis), taraxacum (Herba taraxaci) and malt (Fructus Hordei Germinatus) at a weight ratio of 1:1:1.5:1.5:1.5:1.5:2. A feeding experiment was conducted to determine the effects of TCM on innate immunity of abalone, Haliotis discus hannai Ino. Artificial diets containing 1%, 3%, 5% TCM preparation, 1% hawthorn or 1% astragalus, respectively, were fed to juvenile abalone (initial weight 10.38+/-2.51 g; initial shell length 44.15+/-4.15 mm) for 80 days. A TCM-free diet was used as a control. Each diet was fed to three replicate groups of abalone using a randomized design. The results indicated that phagocytic activity was significantly higher in abalone fed 3%, 5% TCM preparation, 1% astragalus or 1% hawthorn (P<0.05). Respiratory burst activity was significantly higher in abalone fed 1%, 3%, 5% TCM preparation, 1% astragalus or 1% hawthorn (P<0.05). Agglutination titre was significantly higher in abalone fed 5% TCM preparation (P<0.05). Weight gain ratio (WGR), daily increment in shell length (DISL), total haemocyte count (THC), plasma protein concentration, and the activity of acid phosphatase (ACP) were not significantly affected by the TCM preparation (P>0.05). These results indicate that TCM preparation can modulate the immunity of H. discus hannai, and it is very possible that TCM might be used as immunostimulants in abalone farming.     

Applied environmental stresses to enhance the levels of polyphenolics in leaves of hawthorn plants

In this investigation, two species of Crataegus (hawthorn) were chosen because their polyphenolic constituents have recently received greater attention for the treatment of patients with severe heart disease. One-year-old plants of hawthorn ( Crataegus laevigata and C. monogyna ) were subjected to water-deficit (continuous water deprivation), cold (4°C), flooding (immersion of roots of plants in water) or herbivory (leaf removal) stress treatments (each of 10 days duration) in order to assess their effects on levels of polyphenolics, namely (-)-epicatechin, catechin, chlorogenic acid, vitexin, vitexin-2'- O -rhamnoside, acetylvitexin-2'- O -rhamnoside, hyperoside, quercetin, and rutin in the leaves. The working hypothesis followed is that one or more of these stress treatment will elicit increases in the levels of these polyphenolics. Cold stress causes increases in levels of vitexin-2'- O -rhamnoside, acetylvitexin-2'- O -rhamnoside, hyperoside, and quercetin in both Crataegus species. Water-deficit stress increased the productivity of chlorogenic acid, catechin, and (-)-epicatechin in both hawthorn species. Flooding and herbivory caused no net increases, and in some cases, decreases in levels of polyphenolics. These studies indicate that either water-deficit stress or cold stress treatments, or a combination of the two, can be used to enhance the levels of desired polyphenolics in the leaves of these two hawthorn species in a photobioreactor system. These results may have significance for hawthorn in adapting to water-deficit or cold stress and are important considerations for the use of hawthorn in the treatment of heart disease in humans.     

Parasitism of the apple maggot,Rhagoletis pomonella,infesting hawthorns in Washington

Five species of larval parasitoids were reared fromRhagoletis pomonella (Walsh) infested fruit of hawthorn,Crataegus, collected from several locations in southwest Washington over a four year period. A braconid,Biosteres melleus (Gahan), parasitized larvae infesting fruits of a native hawthorn species,Crataegus douglasii Lindl. Another braconid,Opius downesi Gahan, emerged exclusively fromR. pomonella pupae reared from fruits of an introduced species of hawthorn,Crataegus monogyna Jacq. A pteromalid,Pteromalus sp., and two eulophids,Tetrastichus spp., attackedR. pomonella larvae infesting fruits of both hawthorn species. No parasitoids emerged from a total of 4385 pupae reared from apple. Percent parasitism ofR. pomonella was higher inC. monogyna compared toC. douglasii fruits. The highest average levels of parasitism ofR. pomonella inC. monogyna andC. douglasii fruits were 90% and 23% respectively. The kinds of parasitoids, their relative abundances and timing of parasitization on the two hawthorns was related to differences in fruit ripening patterns and its effect on the development ofR. pomonella on these two hosts. Parasitization ofR. pomonella byTetrastichus spp. is a new host record. The detection of these species andPteromalus sp. in southwest Washington are the first records of ectoparasitoids attacking this tephritid.     

中国水稻微核心种质不同生育时期耐冷性鉴定及其相关分析

以204份中国水稻微核心种质为试验材料,进行了水稻发芽期、芽期、幼苗期、孕穗期等耐冷性鉴定及其相关性分析。结果表明,水稻各生育时期耐冷性在籼粳亚种间、各种质之间存在明显的差异。粳稻种质的耐冷性明显强于籼稻种质,但籼稻种质中也存在耐冷性较强的种质。高阳淀稻大红芒、肥东塘稻、木樨球、卫国、兴国、山酒谷、中花8号等粳稻种质和包选21号、红米三担白、寸谷糯、红谷等籼稻种质在水稻各生育时期均表现较强的耐冷性,在水稻耐冷性育种及耐冷基因发掘研究中应加以利用。自然低温和冷水胁迫下水稻结实率与低温下发芽率呈显著或极显著正相关,而与死苗率呈显著负相关,即低温下发芽期耐冷性和芽期耐冷性强的水稻种质一般表现为较强的孕穗期耐冷性。认为低温下发芽率和芽期低温处理后的死苗率可以作为孕穗期耐冷性早期鉴定的间接指标。     

Ecological adaptation and reproductive isolation in sympatry: genetic and phenotypic evidence for native host races of Rhagoletis pomonella

Ecological speciation with gene flow may be an important mode of diversification for phytophagous insects. The recent shift of Rhagoletis pomonella from its native host downy hawthorn (Crataegus mollis) to introduced apple (Malus domestica) in the northeastern United States is a classic example of sympatric host race formation. Here, we test whether R. pomonella has similarly formed host races on four native Crataegus species in the southern United States: western mayhaw (C. opaca), blueberry hawthorn (C. brachyacantha), southern red hawthorn (C. mollis var. texana) and green hawthorn (C. viridis). These four southern hosts differ from each other in their fruiting phenology and in the volatile compounds emitted from the surface of their fruits. These two traits form the basis of ecological reproductive isolation between downy hawthorn and apple flies in the north. We report evidence from microsatellite population surveys and eclosion studies supporting the existence of genetically differentiated and partially reproductively isolated host races of southern hawthorn flies. The results provide an example of host shifting and ecological divergence involving native plants and imply that speciation with gene flow may be commonly initiated in Rhagoletis when ecological opportunity presents itself.     

橄榄ISSR和RAPD遗传多样性分析和核心种质构建

为揭示中国橄榄(Canarium album)种质资源的遗传多样性,采用ISSR和RAPD标记对橄榄主要分布区的86份种质资源进行遗传多样性分析并构建核心种质。结果表明,基于UPGMA遗传相似系数,86份种质资源可分为3个大类;基于STRUCTURE模型聚类,可分为4个类群,这基本符合橄榄的地域性分布规律。采用ISSR和RAPD获得的中国橄榄种质资源的整体遗传多样性水平分别为0.284±0.169和0.244±0.163,多态性位点百分率分别为92.56%和100%,总遗传分化系数分别为0.127和0.142,基因流分别为3.423和3.025,群体间遗传相似系数分别为0.930和0.939,个体间遗传相似系数分别为0.736和0.732。因此,中国橄榄种质资源丰富的遗传多样性主要来源于个体间的遗传分化或变异,且这种遗传多样性存在明显的地域性差异。     

BEHAVIORAL EVIDENCE FOR FRUIT ODOR DISCRIMINATION AND SYMPATRIC HOST RACES OF RHAGOLETIS POMONELLA FLIES IN THE WESTERN UNITED STATES

The recent shift of Rhagoletis pomonella (Diptera: Tephritidae) from its native host downy hawthorn, Crataegus mollis, to introduced domesticated apple, Malus domestica, in the eastern United States is a model for sympatric host race formation. However, the fly is also present in the western United States, where it may have been introduced via infested apples within the last 60 years. In addition to apple, R. pomonella also infests two hawthorns in the West, one the native black hawthorn, C. douglasii, and the other the introduced English ornamental hawthorn, C. monogyna. Here, we test for behavioral evidence of host races in the western United States. through flight tunnel assays of western R. pomonella flies to host fruit volatile blends. We report that western apple, black hawthorn, and ornamental hawthorn flies showed significantly increased levels of upwind‐directed flight to their respective natal compared to nonnatal fruit volatile blends, consistent with host race status. We discuss the implications of the behavioral results for the origin(s) of western R. pomonella, including the possibility that western apple flies were not introduced, but may represent a recent shift from local hawthorn fly populations.     

A field test for host fruit odour discrimination and avoidance behaviour for Rhagoletis pomonella flies in the western United States

Prezygotic isolation due to habitat choice is important to many models of speciation-with-gene-flow. Habitat choice is usually thought to occur through positive preferences of organisms for particular environments. However, avoidance of non-natal environments may also play a role in choice and have repercussions for post-zygotic isolation that preference does not. The recent host shift of Rhagoletis pomonella (Diptera: Tephritidae) from downy hawthorn, Crataegus mollis, to introduced apple, Malus domestica, in the eastern United States is a model for speciation-with-gene-flow. However, the fly is also present in the western United States where it was likely introduced via infested apples ≤ 60 years ago. R. pomonella now attacks two additional hawthorns in the west, the native C. douglasii (black hawthorn) and the introduced C. monogyna (English ornamental hawthorn). Flight tunnel tests have shown that western apple-, C. douglasii- and C. monogyna-origin flies all positively orient to fruit volatile blends of their respective natal hosts in flight tunnel assays. Here, we show that these laboratory differences translate to nature through field-trapping studies of flies in the state of Washington. Moreover, western R. pomonella display both positive orientation to their respective natal fruit volatiles and avoidance behaviour (negative orientation) to non-natal volatiles. Our results are consistent with the existence of behaviourally differentiated host races of R. pomonella in the west. In addition, the rapid evolution of avoidance behaviour appears to be a general phenomenon for R. pomonella during host shifts, as the eastern apple and downy hawthorn host races also are antagonized by non-natal fruit volatiles.     

Cultivated hawthorn (Crataegus pinnatifida var. major) genome sheds light on the evolution of Maleae (apple tribe)

Cultivated hawthorn (Crataegus pinnatifida var. major) is an important medicinal and edible plant with a long history of use for health protection in China. Herein, we provide a de novo chromosome-level genome sequence of the hawthorn cultivar “Qiu Jinxing.” We assembled an 823.41 Mb genome encoding 40 571 genes and further anchored the 779.24 Mb sequence into 17 pseudo-chromosomes, which account for 94.64% of the assembled genome. Phylogenomic analyses revealed that cultivated hawthorn diverged from other species within the Maleae (apple tribe) at approximately 35.4 Mya. Notably, genes involved in the flavonoid and triterpenoid biosynthetic pathways have been significantly amplified in the hawthorn genome. In addition, our results indicated that the Maleae share a unique ancient tetraploidization event; however, no recent independent whole-genome duplication event was specifically detected in hawthorn. The amplification of non-specific long terminal repeat retrotransposons contributed the most to the expansion of the hawthorn genome. Furthermore, we identified two paleo-sub-genomes in extant species of Maleae and found that these two sub-genomes showed different rearrangement mechanisms. We also reconstructed the ancestral chromosomes of Rosaceae and discussed two possible paleo-polyploid origin patterns (autopolyploidization or allopolyploidization) of Maleae. Overall, our study provides an improved context for understanding the evolution of Maleae species, and this new high-quality reference genome provides a useful resource for the horticultural improvement of hawthorn.     

中国水稻微核心种质不同生育时期耐冷性鉴定及其相关分析

以204份中国水稻微核心种质为试验材料,进行了水稻发芽期、芽期、幼苗期、孕穗期等耐冷性鉴定及其相关性分析。结果表明,水稻各生育时期耐冷性在籼粳亚种间、各种质之间存在明显的差异。粳稻种质的耐冷性明显强于籼稻种质,但籼稻种质中也存在耐冷性较强的种质。高阳淀稻大红芒、肥东塘稻、木樨球、卫国、兴国、山酒谷、中花8号等粳稻种质和包选21号、红米三担白、寸谷糯、红谷等籼稻种质在水稻各生育时期均表现较强的耐冷性,在水稻耐冷性育种及耐冷基因发掘研究中应加以利用。自然低温和冷水胁迫下水稻结实率与低温下发芽率呈显著或极显著正相关,而与死苗率呈显著负相关,即低温下发芽期耐冷性和芽期耐冷性强的水稻种质一般表现为较强的孕穗期耐冷性。认为低温下发芽率和芽期低温处理后的死苗率可以作为孕穗期耐冷性早期鉴定的间接指标。