海南岛红毛丹栽培品系资源主要果实性状的比较分析

为明确红毛丹栽培品系果实性状的遗传多样性,本研究对海南省保亭县13个代表性品系的单果重、果肉重、果形指数、可溶性糖、可滴定酸含量等17个果实性状进行测量,并进行性状间相关分析及不同种质聚类分析研究。结果表明,不同性状的品系间变异幅度亦不同,其中果核重变异系数最大(28.83%),可溶性糖含量最小(5.62%)。不同性状指标间存在显著或极显著相关性,单果重与果实横径、果肉厚、果皮重、果肉重呈极显著正相关,与果实纵径、果核重呈显著正相关;果核重与种子纵径和横径呈极显著正相关。果肉重与果肉厚、可食率呈极显著正相关。可食率与可滴定酸含量呈极显著负相关。果实性状聚类分析(平均距离为7.013时)可将13份资源分为5类,第Ⅲ类品系果实各性状综合表现优良,单果重最大,果核小,果肉最多,可直接鲜食,第Ⅴ类品系单果重低,果肉少,可食率较低,酸含量高,口感较其它类较差,适合加工开发利用。研究表明海南省红毛丹栽培品系果实性状存在丰富的多样性,为生产开发、遗传育种等提供了信息参考。     

紫花苜蓿叶性状对干旱的阶段性响应

通过盆栽控水试验,研究了不同生育时期陇东苜蓿(Medicago sativa L.cv.Longdong)叶性状对不同程度干旱的响应。结果表明:(1)随干旱加重,叶干物质含量(LDMC)、叶氮含量(LN)、比叶重(LMA)、叶厚(LT)上升,叶面积(LA)减小,叶磷含量(LP)无明显变化,叶绿素含量(Chl)和叶长宽比(L/W)波动较大。(2)随生育时期的延长,LT、LDMC、L/W和LA变化不明显,LN下降,LP呈倒"V"型趋势,LMA和Chl波动较大。(3)L/W与LN、LT显著负相关;LDMC与LT、LMA显著正相关;LMA与LT、LN显著正相关,与L/W、LP显著负相关;LN与LT显著正相关;LA与LP显著正相关,与LDMC、LMA、LN显著负相关;Chl与其他叶性状均不相关。尽管干旱下陇东苜蓿不同生育时期叶性状响应并未表现出一致的变化,叶性状的差异性变化还是部分反映了陇东苜蓿适应干旱而采取的综合策略。从不同生育时期的差异性反应角度出发,探讨干旱下的叶性状响应是阐明优良牧草紫花苜蓿水分适应性的新的尝试。     

速生早实的热带果树—毛叶枣

毛叶枣,又名缅枣、大西西果,为鼠李科枣属植物滇刺枣(Ziziphus mauritiana)的一个栽培群。由于植株的嫩梢和叶背面着生灰白色绒毛,故称毛叶枣。目前,从缅甸引种栽培的有两个品种:一个是长果形品种,其果实和叶片呈长卵圆形;叶片长约5.4厘米,宽约3.2厘米;果实纵径约3.6厘米,横径约2.1厘米,平均单果重22.7克,含可溶性固形物9—10％,果实具     

苹果果实生长的数学模型及各生长指标间的相关性分析

以富士苹果(Malus domestica‘Fuji’)为试材,测定其果实生长发育期间各生长指标的动态变化,选择5种理论生长方程对纵径、横径、单果重、体积、干重进行拟合,并根据拟合结果确定合适的生长方程建立各生长指标的数学模型,采用多项式拟合建立果形指数变化的数学模型,同时对果实各生长指标之间进行相关性分析。结果表明,果实纵径、横径生长适合选择Logistic方程,单果重、体积、干重适合选择Gompertz方程,果形指数的变化适合采用多项式拟合;果实纵径、横径、单果重、体积、干重两两之间均呈显著正相关,果形指数、果实干物质相对含量均与纵径、横径、单果重、体积、干重之间呈显著负相关,果实密度与纵径、横径、单果重、体积、干重之间呈显著负相关,而与果形指数、果实干物质相对含量之间呈显著正相关。     

云南不同栽培区域油梨果实品质差异分析

以云南9个不同栽培区域‘哈斯’(Hass)油梨果实为试材,在同一条件下分别观测油梨果实主要内在与外观品质,分析云南不同栽培区域油梨果实主要品质差异,为探索云南油梨栽培适宜生态区域提供借鉴。结果表明：(1)油梨果实外观品质以单果重、种子重量、可食率变异系数较大,分别达到31.31%、38.09%和8.08%,并以LJ产区的油梨单果重和可食率最大;油梨果肉内在品质中以脂肪、可溶性蛋白、维生素C(Vc)含量变异系数较大,分别为37.57%、22.42%和17.89%,脂肪含量以BS产区最高,可溶性蛋白和Vc含量均以BN产区最高。(2)油梨果实Vc、总黄酮、脂肪含量以及单果果肉重、果实纵径等显著受到树龄和气候因子的综合影响。其中：树龄与脂肪、可溶性固形物、Vc、总黄酮含量呈正相关关系,与单果果肉重呈显著负相关关系;经度与脂肪、可溶性固形物、干物质、可溶性蛋白含量呈正相关关系;纬度与可溶性固形物、果肉密度、种子长度呈正相关关系,与Vc、总黄酮含量呈显著负相关关系;海拔与脂肪、可溶性固形物、Vc、总黄酮含量呈正相关关系;年平均气温与果肉密度、单果重、单果果肉重、果实纵径呈正相关关系;年平均降雨量与...     

人工授粉对火龙果果实发育的影响

于开花期对红皮红肉类型火龙果进行人工授粉与自然授粉处理,并对不同发育阶段的子房或果实进行解剖观察,以研究人工授粉对果实发育的影响.结果表明:人工授粉可提高火龙果的平均单果重和商品果率,平均单果重与果实内种子数呈显著正相关关系;火龙果子房为多胚珠结构,子房内有若干“珠柄-胚珠”单元,胚珠在开花后发育成种子,珠柄则发育成肉...     

烟草不同基因型耐低氮能力差异评价

以单株叶重及其氮素反应指数作为耐低氮能力的评价指标,分析了烟草种质资源的耐低氮能力以及单株叶重及其氮素反应指数与主要农艺性状间的相关关系。结果表明,不同施氮水平下多数农艺性状基因型间差异较大,在低氮水平下表现最大;和其他农艺性状相比,单株叶重在不同氮素水平间平均差异最大。不同施氮水平下,单株叶重均与最大叶叶面积、单株生物量呈显著或极显著正相关;单株叶重的氮素反应指数与单株叶重、生物量呈显著或极显著正相关,且低氮水平下单株叶重的氮素反应指数与上述性状间的相关性比中氮水平下更为密切。在供试的36个烟草品种中,永定400号、金烟6号、红花大金元、G80、Nc82等烟草种质具有较强的耐低氮能力,可以作为氮高效的烟草品种利用。     

红松和水曲柳叶生态化学计量及养分重吸收特征的地理变异

以我国东北地区4个纬度针叶树种红松和阔叶树种水曲柳为对象,研究两树种成熟叶碳(C)、氮(N)、磷(P)化学计量特征和养分重吸收率及其相关性,分析气候和土壤因子对叶化学计量特征及养分重吸收率的影响。结果表明：叶化学计量特征的地理变异存在种间差异,随着纬度的升高,水曲柳叶C、N含量显著增加;水曲柳C∶N、红松N∶P均与纬度呈显著负相关,而水曲柳N∶P与纬度呈显著正相关。红松磷重吸收率与纬度呈显著正相关。相关分析表明,红松和水曲柳叶的生态化学计量特征主要受到气候因子(年均温和降水量)的影响,而养分重吸收率仅受少数土壤因子(pH和全氮)的影响。主成分分析表明,红松和水曲柳磷重吸收率与N∶P均呈显著负相关,与P含量呈显著正相关;氮重吸收率仅在红松中与P含量呈显著正相关,与N∶P呈显著负相关。水曲柳相比红松更倾向于具有快速投资-收益型特征。     

胡杨、灰叶胡杨果实空间分布及其数量特性的研究

胡杨、灰叶胡杨种间比较,果穗、种子在树冠上的垂直分布均表现为树冠上层最多,中层居中,下层最少,树冠南北侧相比较,南侧果穗量多于北侧.单果种子量在树冠各层次上差异不显著.胡杨单果重是灰叶胡杨的2.68倍,千粒重是灰叶胡杨的1.33倍,单果种子量是灰叶胡杨的2.14倍,单株种子量是灰叶胡杨的1.28倍,而单株果实量灰叶胡杨是胡杨的1.59倍.同一个种不同居群间比较,胡杨、灰叶胡杨均是单株果穗数和果穗果实数各居群间都存在差异,胡杨各居群间单果重、单果种子量差异不显著,而灰叶胡杨各居群间单果重及单果种子量差异极显著.表明胡杨在物质和能量上对后代的投资能力强于灰叶胡杨,生殖策略是通过较高的单果种子量来保证一定数量的单株种子量;而灰叶胡杨单果种子量较低,却是通过较高的单株果量来保证单株种子量,并且较小的种子占据空间生态位的潜能较胡杨占优势.     

中亚热带樟科3种植物幼苗叶结构型性状的种间差异及其相关性

为了揭示植物叶功能性状对全球气候变化的响应和适应规律,以樟科3种植物幼苗为研究对象,将其人工采集的种子经低温沙藏并于温室培育,然后将幼苗移栽到野外同质园中自然生长,研究中亚热带樟科植物刨花楠(Machilus pauhoi)、香樟(Cinnamomum camphora)和闽楠(Phoebe bournei)两年生幼苗生长季节9种叶结构型性状的种间差异及其相关性。结果显示,(1)在3种植物幼苗中,香樟叶面积、叶厚度、叶体积、叶氮磷比最大,叶氮浓度最高,叶组织密度最小;闽楠叶组织密度、叶干物质含量最大,叶磷浓度最高,叶面积、叶体积、比叶面积、叶氮磷比最小,叶氮浓度最低;刨花楠比叶面积最大,叶厚度、叶干物质含量最小,叶磷浓度最低;3种植物幼苗的叶厚度之间均无显著差异。(2)Pearson相关分析和线性回归分析结果表明,樟科3种植物幼苗的叶面积与叶体积间呈极显著正相关(P0.01)、与叶干物质含量间呈极显著负相关(P0.01)、与叶磷浓度间呈极显著负相关(P0.01)、与叶组织密度间呈显著负相关(P0.05)、与叶氮浓度间呈显著正相关(P0.05);叶厚度与比叶面积间呈显著负相关(P0.05)、与叶干物质含量间呈显著正相关(P0.05);叶体积与叶组织密度间呈极显著负相关(P0.01)、与叶氮浓度间呈极显著正相关(P0.01)、与叶磷浓度间呈显著负相关(P0.05);叶组织密度与叶磷浓度间呈显著正相关(P0.05);比叶面积与叶干物质含量间呈极显著负相关(P0.01)、与叶磷浓度间呈极显著负相关(P0.01);叶干物质含量与叶磷浓度间呈极显著正相关(P0.01)。这表明在同质园中生长的刨花楠、香樟和闽楠幼苗的9种叶结构型性状表现出一定的种间差异,不同物种同一叶结构型性状指标的大小顺序、种间差异及其显著性不同;3种植物幼苗不同叶结构型性状之间的相关性及其显著程度也不同。本研究结果为揭示樟科3种植物幼苗叶功能性状对全球气候变化的响应和适应规律提供了基础数据。     

Relative growth rate of leaf biomass and leaf nitrogen content in several mediterranean woody species

In many plant species, herbivory is a major determinant of leaf mortality and it can cause a strong reduction in productive potential. Most predation occurs on young, expanding leaves. Thus, a rapid growth of the leaves can reduce the impact of predation. Furthermore, in cold Mediterranean climates the length of the growing season is constrained to a short period in spring and early summer owing both to low winter temperatures and drought stress in early summer. Therefore, a rapid deployment of leaf area and a high photosynthetic capacity during the spring and early summer might have important positive effects on the final carbon balance of the leaf population. Relative growth rates (RGR) of leaf biomass were measured in 19 woody species typical of Central Western Spain with deciduous and evergreen habits. Highly significant differences were detected in the leaf growth rate of the different species. The differences between species, however, did not correlate either with the mean leaf life-span of each of the species or with other leaf traits such as photosynthetic capacity, specific leaf area or nitrogen content. Leaf growth rate was positively correlated with time elapsed between leaf initiation and fruit maturation, so that species with fruit dispersal in spring and early summer in general had lower leaf growth rates than species with autumn fruit shedding. This relationship shows the effects of the concurrence between vegetative and reproductive organs for nutrients and other resources. Nitrogen concentration in the leaves was very high at the time of bud break, and declined during leaf expansion owing to the dilution associated with the increase in structural components. The rate of nitrogen dilution was, thus, positively related to the leaf growth rate. Relative growth rates calculated for nitrogen mass in leaves were very low compared to the growth in total mass. This suggests that most leaf nitrogen is translocated from the plant stores to the leaf biomass before the start of leaf expansion and that the contribution of root uptake during leaf expansion is comparatively low.     

Seasonal Changes in the Photosynthetic Rate in Apple Trees : A Comparison between Fruiting and Nonfruiting Trees

Seasonal changes in photosynthesis of apple trees (Malus domestica Borkh.) were monitored to examine the effect of source-sink interactions on photosynthesis and photorespiration. Elevated photosynthetic rates were observed during two periods of the growing season and correlated with the fruiting process. The first period of increased photosynthetic rates was during the bloom period, when spur leaves on flowering shoots exhibited up to 25% higher photosynthetic rates than vegetative spur leaves on a leaf area basis. CO₂ assimilation rates were also higher in fruiting trees than nonfruiting trees during the period of rapid fruit growth from July to September. Photorespiration, dark respiration, leaf resistance, and transpiration exhibited no seasonal changes which correlated to the presence or absence of fruit. These data represent the first comprehensive examination of the effects of flowering/fruit formation on photosynthesis and photorespiration in perennial plants.     

黄花倒水莲生长与内源激素水平动态变化关系研究北大核心CSCD

为探索黄花倒水莲春梢生理生化特性的差异以及不同内源激素的变化规律,该文对黄花倒水莲春梢的生长动态进行监测,采用间接酶联免疫吸附法(ELISA)测定脱落酸(ABA)、生长素(IAA)、赤霉素(GA)、乙烯(ETH)和玉米素核苷(ZR)五种内源激素含量的动态变化,并对两者间的相关性进行分析。结果表明:(1)黄花倒水莲春梢生长发育过程可分为快速增长期(0~12 d)、生长转折期(16~20 d)和缓慢增长期(24~32 d)三个阶段。(2)内源激素ABA、GA、ETH和ZR含量在缓慢增长期显著高于快速增长期和生长转折期,IAA含量各时期差异较小。(3)春梢长、底部叶长和叶宽在快速增长期与ABA、GA、ETH和ZR含量呈负相关,且与ZR含量具有一定显著性,与IAA含量呈正相关;生长转折期,各指标与GA、ETH和ZR含量呈正相关,与GA含量具有一定显著性,与ABA含量呈负相关;缓慢增长期,各指标与五种内源激素含量均呈正相关,与IAA和ZR含量具有一定显著性。该研究结果为生产上利用外源激素调控黄花倒水莲春梢抽出以及生长提供了理论基础。     

Seasonal variations of leaf water potential and growth in fertigated carob-trees (Ceratonia siliqua L.)

Variations of predawn and midday leaf water potential and relative growth rates were studied in mature carob trees (Ceratonia siliqua L. cv Mulata) submitted to a fertigation experiment. Three levels of irrigation were tested: 0%, 50% and 100%, based on daily standard evaporation values. For each irrigation level two nitrogen amounts were applied –21 and 63 kg N ha^-1 year^-1 as ammonium nitrate. The experiment was run between July 91 and August 1993. Measurements of leaf water potential and absolute branch length increments were made at monthly intervals, during the entire experimental period or during seasonal growth, respectively. Leaf water potential was related to soil volumetric water content, maximum and minimum air temperature and daily evaporation. Predawn leaf water potentials were always higher than –1.1 MPa. Midday leaf water potential values presented very large seasonal variations and very low values independent of treatments. The low leaf water potentials observed for the fertigated trees during summer, suggest that this parameter may be related not only to the evaporative demand but also to growth investment. The amount of fertigation was positively correlated with vegetative growth increment and fruit production. Practical implications for irrigation schedules of leaf water potential patterns together with drought adaptation mechanisms of carob tree are discussed.     

Vegetative phenology of alpine plants at Tateyama Murodo-daira in central Japan

The vegetative phenology of 29 alpine species, including herbaceous and woody summergreens and evergreens, was investigated. Summergreen species initiated and completed leaf growth earlier than evergreen species. The green period of leaves in summergreen plants was determined largely by the time of growth initiation. Early initiation of growth in summergreen plants contributes to the increase in photosynthetic carbon gain. Early cessation of growth in summergreens is advantageous for the growth in the following year because it leads to an increase in stored photosynthates. The growth period of leaves and stems in alpine plants correlated with the time of growth initiation more strongly than with the time of growth cessation, indicating the importance of early growth initiation for the increase in plant growth. The growth period of leaves was positively correlated with the sum of leaf lengths and the number of leaves. Herbs with a long growth period of more than 50 days had perennial shoot axes not terminated by inflorescences, suggesting a relationship between the growth period and shoot habit. Two summergreen species were completely dead by mid-September, before the air temperature decreased below 0°C. The remaining summergreen species died immediately after the air temperature decreased to −1.4°C in late September.     

宁夏枸杞果实内源激素的变化及其与细胞壁成分和相关酶的关系

采用高效液相色谱技术, 研究了不同发育时期宁杞1号和宁杞5号枸杞(Lycium barbarum)果皮和种子内源激素(玉米素(ZT)、赤霉素(GA₃)、生长素(IAA)和脱落酶(ABA))含量与果实生长发育的关系。结果表明, 宁杞5号果实横纵径和单粒重均大于宁杞1号, 果实发育前期, 尤其是缓慢生长期, 是宁杞5号果实大小和重量积累的关键时期。宁杞1号种子中的生长素含量与果实横径和果实单粒重均呈极显著正相关, 与果实纵径呈显著正相关。宁杞5号果皮中玉米素含量与果实横径和单粒重均呈显著正相关, 种子中生长素含量与果实横径和单粒重均呈显著正相关。玉米素促进细胞的分裂, 而细胞数目比细胞体积对决定果实大小的作用更大; 在缓慢生长期(开花后8–25天), 宁杞5号果皮和种子中的脱落酸含量均显著小于宁杞1号。以上两点可能是宁杞5号的横纵径和单粒重均大于宁杞1号的主要原因。宁杞1号果皮中的GA₃与半纤维素酶(Cx)活性的变化相反, 说明宁杞1号果实发育前期和中期果皮中高含量的GA₃对细胞壁中Cx活性有一定的抑制作用, 从而表现出果实膨大。宁杞5号果皮中的IAA与多聚半乳糖醛酸酶(PG)和果胶酯酶(PE), ZT与PE, ABA与Cx, 种子中的ZT与PE的变化均相反, 说明宁杞5号果实发育前期和中期果皮中高含量的IAA、ZT、ABA及种子中的ZT可促进果实的膨大。推测这可能是宁杞5号果实单粒重大于宁杞1号的主要原因之一。宁杞5号果皮中的ZT和种子中的IAA可以增强Cx的活性; 宁杞1号果皮中的ABA可以增强PE的活性, 进而促进果实的成熟。     

REPRODUCTIVE BIOLOGY OF ASCLEPIAS EXALTATA

An analysis of the relationships between plant size and survivorship and reproductive success was carried out by sampling four populations of the herbaceous perennial milkweed Asclepias exaltata in Virginia from 1980 to 1982. The annual survivorship rate (about 65%) is the lowest measured for any species of Asclepias. Survivorship was strongly size-dependent but showed no clear relationship with previous history of fruit production. Non-flowering plants were significantly smaller than flowering plants and showed very strong (r > 0.87) correlations between root dry weight and stem or leaf dry weight. Flowering plants were similar to nonflowering plants in root: shoot ratio (approximately 1:1) but differed in that root dry weight was not strongly correlated with stem or leaf dry weight. Components of inflorescence size were strongly correlated within a given level of comparison (e.g., stems per plant with flowers per plant) but less strongly correlated between levels (e.g., stems per plant with flowers per stem). Number of fruits per plant and percentage fruit-set were positively correlated with every component of inflorescence size. Although overall fruit-set was low (about 2%), fruits that were initiated had a high probability of surviving to maturity. There was no evidence of an early period of high fruit abortion: a relatively constant proportion of fruits aborted between each age class.     

GROWTH AND DEVELOPMENT OF LITCHI CHINENSIS AS AFFECTED BY SOIL-MOISTURE STRESS

The effects of soil-moisture tension on growth and floral development of field-grown Litchi chinensis, a woody subtropical fruit tree, were investigated. Floral initiation and fruit set were promoted by a high soil-moisture tension for 6 months, beginning with June, 1967, or for 4 months, beginning with October, 1967. The normal floral-initiation period in Hawaii is during the period November to January. The apical meristematic tissue, judged from the number of branches flowering, was apparently not adversely affected by a soil-moisture stress, provided adequate water was available during the floral-bud development period. Low soil-moisture tension (0.3 bar) throughout the experimental period was inhibitory for floral bud initiation. High soil-moisture tension inhibited growth of the trunk and the emergence of flush-growths. Flowering was correlated significantly, and negatively, with growth. Leaf nitrogen and potassium levels were unaffected by water stress, but the phosphorus levels in leaf and stem were lowered by high-moisture tension. Hydrolysis of starch under moisture stress, reported for some species, was not evident in the Litchi. No correlation between trophic constituents and flowering was observed.     

Partitioning of (13)C-photosynthate from spur leaves during fruit growth of three Japanese pear (Pyrus pyrifolia) cultivars differing in maturation date

BACKGROUND AND AIMS: In fruit crops, fruit size at harvest is an important aspect of quality. With Japanese pears (Pyrus pyrifolia), later maturing cultivars usually have larger fruits than earlier maturing cultivars. It is considered that the supply of photosynthate during fruit development is a critical determinant of size. To assess the interaction of assimilate supply and early/late maturity of cultivars and its effect on final fruit size, the pattern of carbon assimilate partitioning from spur leaves (source) to fruit and other organs (sinks) during fruit growth was investigated using three genotypes differing in maturation date. METHODS: Partitioning of photosynthate from spur leaves during fruit growth was investigated by exposure of spurs to (13)CO(2) and measurement of the change in (13)C abundance in dry matter with time. Leaf number and leaf area per spur, fresh fruit weight, cell number and cell size of the mesocarp were measured and used to model the development of the spur leaf and fruit. KEY RESULTS: Compared with the earlier-maturing cultivars 'Shinsui' and 'Kousui', the larger-fruited, later-maturing cultivar 'Shinsetsu' had a greater total leaf area per spur, greater source strength (source weight x source specific activity), with more (13)C assimilated per spur and allocated to fruit, smaller loss of (13)C in respiration and export over the season, and longer duration of cell division and enlargement. Histology shows that cultivar differences in final fruit size were mainly attributable to the number of cells in the mesocarp. CONCLUSIONS: Assimilate availability during the period of cell division was crucial for early fruit growth and closely correlated with final fruit size. Early fruit growth of the earlier-maturing cultivars, but not the later-maturing ones, was severely restrained by assimilate supply rather than by sink limitation.     

Effects of converting natural forests to coniferous plantations on fruit and seed production and mating patterns in wild cherry trees

Landscape disturbances can affect reproductive performance of animal-pollinated trees. We verified the effects of the loss and fragmentation of natural forests caused by the creation of coniferous plantations on fruit and seed production as well as mating patterns of animal-pollinated trees. We investigated 146 and 134 individual flowering trees of Prunus verecunda (Koidz.) Koehne in 2012 and 2013, respectively, at 12 sites. These sites were at least 1.2 km apart from each other in an 8 × 15-km forestry region, and the composition and configuration of natural forests varied in the study area. The mean outcrossing rate was >0.99 across the sites. Among trees within the sites, the number of fruits per inflorescence was positively correlated with the basal stem area and leaf chlorophyll density of the trees. Among the sites, the mean number of fruits per inflorescence was positively correlated with the site elevation, and the correlated paternity was positively correlated with the mean distance between trees. The sound-seed rate was positively correlated with the natural-forest area among the sites. These results suggest that environments and resources of trees influence their fruit production, that a loss of natural forests increases in embryo mortality, and that a reduction in tree density decreases pollen donor diversity in P. verecunda. Thus, a landscape disturbance may decrease seed production, whereas outbreeding is maintained, and fruit production is not likely to be dependent on the landscape disturbance in this species.