干旱胁迫对福建山樱花和日本樱花幼苗内源激素的影响

以1年生福建山樱花和日本樱花实生苗为试材,设置对照(CK)、轻度干旱胁迫(LS)、中度干旱胁迫(MS)、重度干旱胁迫(HS)4种处理,探究干旱胁迫对福建山樱花和日本樱花幼苗内源激素的影响。结果表明:2个树种在LS处理下,GA3(赤霉素)和IAA(生长素)的含量均高于对照,ABA(脱落酸)的含量和对照无显著差异。在MS和HS处理下,GA3和IAA含量呈现明显降低趋势,ABA、ABA/GA3和ABA/IAA的含量呈现明显的增加趋势。随着干旱胁迫处理时间的延长,在LS处理下,GA3、IAA和ABA的含量无显著变化,而MS和HS处理中,GA3和IAA含量呈现出下降趋势,ABA含量、ABA/GA3和ABA/IAA呈增加的趋势。随着干旱胁迫程度的加深,福建山樱花ABA、GA3、IAA、ABA/GA3和ABA/IAA的含量均要低于日本樱花,这表明日本樱花比福建山樱花可能存在着更强的通过调节自身的激素水平来应对外界干旱胁迫的能力,这可能正是日本樱花比福建山樱花更加抗旱的生理机制之一。     

2种樱属植物对水湿胁迫生理响应研究

对2种樱属植物福建山樱花和樱桃幼苗进行人工模拟水湿胁迫,在不同处理时间取其根系和叶片测定相对电导率、叶绿素、可溶性蛋白、脯氨酸、超氧物歧化酶和丙二醛等生理指标。结果显示:樱桃在第6天即表现出萎蔫状态,而福建山樱花在第8天才出现萎蔫;从生理指标测定来看,2种植物根部各生理指标均低于叶片,其中福建山樱花可溶性蛋白降解速度比樱桃慢,而且超氧化物歧化酶(SOD)活性和脯氨酸含量更高;从两者地上部与地下部生理指标变化的同步性来看,福建山樱花也优于樱桃。由此判断,福建山樱花抗水湿能力大于樱桃。     

福建山樱花观赏特征与开花生物学特性的初步研究

研究不同种源福建山樱花的叶、花、果实和种子等观赏特征和开花习性、开花过程、开花节律、开花顺序、开放时间、开花持续时间等开花生物学特性,并讨论温度对福建山樱花开花物候的影响。     

茶园三种间作模式对小贯小绿叶蝉及其天敌功能团群落的影响

为探讨茶园间作对茶园小贯小绿叶蝉（Empoasca onukiiMatsuda）的生态调控作用,本研究开展樱花（Cerasus sp.）、圆叶决明（Chamaecrista rotundifolia）、油菜（Brassica napus L.）间作茶园中小贯小绿叶蝉种群时序动态,及其天敌功能团组成结构、种群数量时序变化调查,分析间作茶园中小贯小绿叶蝉天敌功能团群落多样性和益害比。结果显示：樱花-茶、圆叶决明-茶和油菜-茶中小贯小绿叶蝉的时间动态变化趋势与常规茶园无显著差异,但发生量较同期常规茶园显著下降（P=0.034<0.05）,全年分别下降25%~225%、20%~82.6%和20%~100%;经调查、鉴定得出,同期茶园小贯小绿叶蝉天敌功能团隶属于蜘蛛目、脉翅目和膜翅目,共计9个科、12个种,均为肉食性节肢动物;不同间作茶园中小贯小绿叶蝉天敌功能团种群的优势种、从属种和偶见种存在差异;与常规茶园相比,樱花-茶、圆叶决明-茶可显著提高蜘蛛、捕食性昆虫和寄生性昆虫的种群数量（P<0.05）,油菜-茶可显著提高茶园中捕食性昆虫和寄生性昆虫的发生量,但对蜘蛛的发生量无显著影响;樱花-茶的小贯小绿叶蝉与天敌功能团益害比显著高于油菜-茶和圆叶决明-茶;多样性指数分析显示,樱花-茶、圆叶决明-茶、油菜-茶的小贯小绿叶蝉天敌功能团群落多样性与常规茶园存在显著差异,且通过聚类分析得出,当兰氏距离为4.79时,茶树间作模式分为2类,一类为常规茶园,一类为樱花-茶、油菜-茶和圆叶决明-茶。研究结果表明,间作樱花、圆叶决明、油菜能有效降低茶园中小贯小绿叶蝉的发生量,提高天敌功能团的种群数量和益害比,对小贯小绿叶蝉的发生起到明显的生态控制作用。     

青龙寺茶思

正一虽说错过了观赏春天樱花的烂漫,却在秋末冬初的时节,看到了大片樱花落叶之静美。眼前,冷风劲吹,樱花叶子纷纷坠地,不时还在空中飞舞,把树下铺积成了金黄色的毯子,开始孕育着来年春天的盛景。此时此刻,我在古城西安城外南郊的乐游原上,一个名为青龙寺遗址公园里徜徉,寻觅一种感觉和前所未有的发现。想当年,唐代诗人李商隐来到此地,曾满含深情地吟     

珍稀植物海南粗榧培育技术

海南粗榧为中国二级濒危物种,被认为是最具潜力的天然抗癌药用植物。为促进海南粗榧的研究和发展,简要介绍海南粗榧,结合其资源分布生境特点,总结和分析海南粗榧苗木繁殖与栽培技术。     

福建山樱花及其近缘物种研究现状与开发利用

介绍福建山樱花的形态特征与生态习性及部分近缘物种观赏价值,详细评述了福建山樱花及其近缘物种的国内外研究情况,并提出今后开发利用的几点建议.     

环境因子对海南大叶种茶苗期生长的影响

[目的]探索环境因子与海南大叶种茶扦插苗苗期生长的关系,为海南大叶种茶的种植提供参考。[方法]通过对6个样地的海南大叶种茶苗期生长指标和环境因子的监测,研究环境因子对海南大叶种茶苗期生长的影响。[结果]海南大叶种茶苗期地径和叶面积的变化与土壤总氮和有机碳呈极显著的正相关,株高与海拔呈显著正相关,相对叶绿素与空气湿度呈显著负相关,与海拔呈极显著负相关。五指山市海南大叶种茶苗期生长主要受到空气温度、湿度和土壤水分的影响。[结论]当温度范围为21.14～26.58℃,湿度范围为86.82%～89.99%,土壤水分范围为0.27～0.35时,海南大叶种茶生长状况良好。     

冬樱花扦插生根处理研究

采用不同质量百分数浓度的NAA、国光生根剂(20% NAA)、根旺(NAA、IBA各占1%)溶液浸渍冬樱花插穗15～30 s,进行扦插生根试验。结果表明：NAA＋IBA组合使用明显优于NAA单独使用,500 mg/kg根旺(NAA　250 mg/kg＋IBA　250　mg/kg)时冬樱花扦插生根率最高,达80.3%。此繁殖方法可以在冬樱花推广种植时应用。     

海南生鲜蔬菜冷链物流系统构建及发展对策研究

针对海南蔬菜流通存在的冷链流通比例低、冷链基础设施不足、流通损耗大等问题,分析海南蔬菜冷链物流现状,借鉴国内外冷链物流运营模式,构建4种主要海南蔬菜冷链物流系统模式。依据目前海南冷链存在的关键问题及发展趋势,海南蔬菜冷链物流系统的发展以批发市场为主导的系统模式发展阶段、多种模式共同发展阶段和多模式下资源整合阶段3个阶段。通过4种主要海南冷链物流系统构建以及其适应性特征分析,为海南地区冷链物流系统的发展起指导作用,为政府在此方面的规划提出参考建议。     

几种千斤拔属饲用植物单宁含量动态分析

测定了5种（6份种质）千斤拔属（Flemingia Roxburgh ex WT. Aiton）饲用植物茎、叶在不同月份（2010年6月至2011年5月）的单宁含量，揭示其动态变化趋势。结果表明：6份千斤拔叶片单宁平均含量由低到高依次为大叶千斤拔Ⅰ（种质源自海南，1.82％）＜腺毛千斤拔（1.93％）＜大叶千斤拔Ⅱ（种质源自越南，2.17％）＜海南千斤拔（2.28％）＜球穗千斤拔（2.55％）＜宽叶千斤拔（2.70％）；茎中单宁平均含量由低到高顺序为大叶千斤拔Ⅰ（种质源自海南，1.05％）＜球穗千斤拔（1.08％）＜腺毛千斤拔（1.43％）大叶千斤拔Ⅱ（种质源自越南，1.56％）＜宽叶千斤拔（1.60％）＜海南千斤拔（1.64％）。6份千斤拔叶片的单宁含量均高于相应的茎含量，并随月份的推移而变化。这表明千斤拔单宁的含量受种类、器官及生长时期的影响。     

基于ISSR分子标记的海南凤仙花种群遗传多样性

运用ISSR分子标记技术,分析海南岛石灰岩地区海南凤仙花自然种群的遗传结构,比较3个海拔梯度对种群遗传结构的影响。结果显示,13个ISSR引物的扩增结果显示其多态性位点百分率为97.7%。AMOVA分析表明:海南凤仙花自然种群的变异主要来自种群内(92%),而种群间变异较少(8%);中海拔种群的遗传多样性最为丰富;而高海拔种群的遗传多样性则较低;种群的遗传距离和地理距离表现出显著的高度相关性。说明海拔是影响种群基因流的重要因素,高海拔种群可以向中低海拔种群进行传播花粉和种子等基因流动,而中低海拔种群向高海拔种群进行类似的基因流动则较为困难,海南凤仙花数量较少的主要原因可能来自于其生境的限制。因此在以后的保护工作中要特别注重其生境的保护,避免人为因素的破坏。     

西双版纳橡胶树主要害螨及优势种螨类天敌种类调查

2010~2012年通过对西双版纳州橡胶林的害螨及其天敌进行2年多的调查。结果表明:西双版纳州橡胶树害螨主要有2种,分别为六点始叶螨(Eotetranychus sexmaculatus Riley)和海南小爪螨(Oligonychus hainanensis Ma,Yuan et Lin);并详细记述了2种害螨的形态特征、为害特点及发生数量;初步调查到六点始叶螨的天敌19种,隶属2个纲、7个目、10个科,采用优势度指数评价法得出优势种群为草蛉、食螨瓢虫和捕食螨,三者都具有较好的应用前景;初步摸清六点始叶螨主要天敌发生消长及其自然控制作用。     

海南橡胶园捕食螨种类调查及优势种评价

为摸清海南橡胶园捕食螨种类及其优势种,本研究于2015—2016年,采用五点取样法进行捕食螨种类的调查采集,采用优势度和频度等指标进行优势种评价。结果表明：海南橡胶园的捕食螨有植绥螨科、囊螨科和吸螨科等3个科,其中,植绥螨科的数量最多,占样本总数的85.05%,其次是囊螨科,占样本总数的14.71%,吸螨科捕食螨的数量最少,占样本总数的0.24%。对植绥螨科的4属13种捕食螨进行综合评价表明邻近钱绥螨（Chanteius contiguus）、普通真绥螨（Euseius vulgaris）、海南钝绥螨（Amblyseius hainanensis）是海南南部橡胶园的优势种捕食螨,而卵圆真绥螨（Euseius ovalis）是海南北部橡胶园的优势种捕食螨,南部和北部橡胶园的优势种捕食螨种类及数量存在较大差异。本研究结果可为进一步利用捕食螨防治六点始叶螨（Eotetranychus sexmaculatus）、东方真叶螨（Eutetranychus orientalis）等橡胶叶螨的生物防治提供理论依据。     

海南莎草科植物资源新探

通过野外资源调查,结合现阶段生物多样性发展需求对海南莎草科植物进行系统性、科学性的整理。结果发现,海南现有莎草科植物为24属、157种、9亚种和4变种。调查新增三肋果莎属（Tricostularia Nees）;新增新种长柄薹草（Carex longipetiolata）;新增11个新分布记录种,分别是细秆湖瓜草（Lipocarpha tenera）、类头状花序藨草（Trichophorum subcapitatum）、复序飘拂草（Fimbristylis bisumbellat）、宽叶多脉莎草（Cyperus diffusus var. Latifolius）、密穗莎草（C. eragrostis）、水蜈蚣（Kyllinga polyphylla）、三肋果莎（Tricostularia undulate）、截鳞薹草（Carex truncatigluma）、广东薹草（C. adrienii）、密苞叶薹草（C. phyllocephala）、中华薹草（C. chinensis）;调查统计发现12个海南特有种,分别是海南割鸡芒（Hypolytrum hainanense）、少穗割鸡芒（H. paucistrobiliferum）、节茎藨草（Scirpus chunianus）、澄迈飘拂草（Fimbristylis chingmaiensis）、多花剑叶莎（Machaerina myriantha）、海南高秆莎草（Cyperus exaltatus var. Hainanensis）、海南砖子苗（Mariscus hainanensis）、单子砖子苗（M. Monospermus）、线茎薹草（Carex tsoi）、扁茎薹草（C. planiscapa）、东方薹草（C. tungfangensis）、岩生薹草（C. Saxicola）。     

海南粗榧外植体灭菌与愈伤组织诱导

对海南粗榧茎段外植体灭菌和愈伤组织诱导实验研究表明,以海南粗榧温室扦插苗的嫩茎作为外植体,70％酒精1min,0．1％氯化汞溶液12min表面消毒处理效果最好;最适愈伤组织诱导培养基为MS＋0．5mg／LNAA＋0．5～1．0mg／LBA＋2．5～4．0mg／L2,4～D。     

Seed production in grassland species: Morpho‐biological determinants in a species‐rich semi‐natural grassland

Studying the seed production of herbaceous species can help to conserve grassland habitats and re‐create new high‐value grassland surfaces. Studies on grassland seed production have focused mainly on individual species and traits, without characterizing their relative importance at the plant community level. The aim of this study was to investigate the entire seed production process of the main species in a temperate grassland. Fertile shoots (FS) of twenty‐nine grasses and forbs were collected over 4 years and analysed for sixteen traits that determine inflorescence size, seed production and seed quality. The per cent viability played a predominant role in determining the total production of viable seeds. Forbs showed a range of reproductive strategies, including variable distribution of flowers among growth periods, number of inflorescences per FS and relationship between seed size and FS density in the grassland. The flower production for grasses was concentrated in the first growth period, but this limitation was mitigated by a higher seed dormancy. The number of viable seeds per FS and seed size were important components of the reproductive strategy of forbs, with heavy‐seeded species being characterised by high individual densities in the community, but producing few seeds per FS. Light‐seeded species showed an opposite pattern. The results suggest that when using seeds from semi‐natural grasslands for ecological restoration, special attention should be paid to the seed amount, germinability and viability of forbs, as they seem to depend more on seed reproduction and have a lower ovule to seed transformation efficiency.     

Weed Seed Bank Dynamics

Summary

Weeds continue to have major impacts on crop production in spite of efforts to eliminate them. Most weed species rely on seed for regeneration and persistence. The species composition and density of weed seed in the soil vary greatly and are closely linked to the cropping history of the land. Altering tillage practices changes patterns of soil disturbance and weed seed depth in the soil, which plays a role in weed species shifts. Crop rotation and weed control practices also impact the weed seed bank in the soil. Information on the weed seed bank should be a useful tool for integrated weed management. Decision aid models are being developed that use information on the composition of the weed seed bank to estimate weed populations, crop yield loss, and to recommend weed control tactics. Understanding weed seed bank dynamics can also be used to guide management practices. Improving and applying our understanding of weed seed and seed bank dynamics is essential to developing improved weed management systems.     

Analysis of seed yield components in four Mediterranean annual clovers

Annual leguminous forage crops are well adapted to hay production under the climatic conditions of Mediterranean environments, but their seed yield is often reduced by high temperatures and water stress that occur during the reproductive period. Field experiments using four forage legumes, berseem (Trifolium alexandrinum L.), crimson clover (Trifolium incarnatum L.), Persian clover (Trifolium resupinatum L.) and squarrosum clover (Trifolium squarrosum L.) were conducted in Foggia (southern Italy) during 1993 and 1994 under irrigated and non-irrigated conditions, with the aim to evaluate: (i) the effects of water deficit on traits which influence seed yield and (ii) the associations among seed yield components by means of path-coefficient analysis. Seed yield varied among species: Persian and berseem clovers showed the highest and lowest values (74.0 and 27.0 g m⁻², respectively). Drought stress, in all species, negatively influenced the dry matter proportion partitioned to reproductive growth and strongly reduced seed yield (about 50% on average) and seed yield components in all species. Negative associations between the principal yield components were found in all species except berseem, suggesting the existence of compensatory relationships. Path-coefficient analysis revealed that for crimson and Persian clovers, the early flowering species, a seed yield increase cannot be achieved without a suitable tiller density. For squarrosum clover, the head fertility was the most important component in determining seed yield; whereas for berseem, seeds per head, heads per tiller and seed weight, all had positive direct effects on seed yield. As the yield components that most affected seed yield were species-specific, general conclusions cannot be drawn. Among the species examined, berseem and squarrosum clover, characterized by a longer vegetative cycle, were more damaged by water stress when it occurred during seed formation and filling.