刺木蓼和长枝木蓼种子休眠的解除及萌发条件

刺木蓼（Atraphaxis spinosa）和长枝木蓼（A.virgata）为蓼科木蓼属灌木,是乌鲁木齐周边植被组成的重要种。这两种木蓼种子成熟后不萌发,处于休眠状态,对其种子进行5℃（黑暗）和野外低温层积处理,结果表明：5℃层积处理能明显提高两种木蓼种子在15/6、20/10、25/15和30/20℃（昼12 h/夜12 h）的萌发率。野外层积处理显著提高了种子在15/6℃的萌发率。刺木蓼和长枝木蓼的种子均为非深度生理休眠,分别经8、6周的低温层积处理后种子休眠得以解除。刺木蓼种子的休眠程度比长枝木蓼深,休眠解除后,种子萌发所需的最低温度降低。这两种木蓼种子经过冬天的低温层积,可以在春天较低的生境温度下萌发。     

4种野生植物种子萌发对短期室温干贮藏的响应

了解野生植物种子萌发对短期室温干贮藏的响应,可解释本地野生植物被用于植被恢复中的种子出苗情况,还可以为种子萌发策略及其种群更新研究提供科学依据。本研究以用于飞播的4种野生植物为研究材料,探讨了成熟鲜种子的萌发温度、短期室温干贮藏后种子生活力以及休眠和萌发的变化。结果表明：顶羽菊（Rhaponticum repens）、糙苏（Phlomis umbrosa）和花花柴（Karelinia caspia）成熟鲜种子在25/15℃下萌发率高,分别为27%、98%和100%左右。在三个温度条件下铃铛刺（Halimodendron halodendron）种子萌发率没有明显变化,最高萌发率为46%左右。顶羽菊和铃铛刺绝大部分种子具有休眠现象。经过短期室温干贮藏后,顶羽菊和花花柴种子死亡率极高,分别为72%和88%左右。除糙苏种子萌发率明显降低10%外,铃铛刺、花花柴和顶羽菊种子经短期室温干贮藏后萌发率没有明显变化。基于本研究结果,在飞播中应慎用顶羽菊和花花柴种子,铃铛刺种子播种前需要擦破种皮处理。     

两种野生灌木幼苗对干旱和盐交叉胁迫的生理响应

长枝木蓼(Ateaphaxis viegata)和刺叶锦鸡儿(Caragana acanthophulla)是乌鲁木齐周边植被组成的重要种,在植被恢复中具有潜在价值。该文通过盆栽控水控盐法研究两种野生灌木幼苗在不同程度的干旱和盐交叉胁迫下的生理反应。结果表明,干旱和盐交叉胁迫下,长枝木蓼可溶性糖增幅较刺叶锦鸡儿大;轻度交叉胁迫时,两种灌木的可溶性糖含量高于仅干旱胁迫或盐胁迫下的。中度和重度交叉胁迫下,长枝木蓼叶片丙二醛含量增幅高于刺叶锦鸡儿。交叉胁迫下,两种灌木叶片叶绿素含量下降,且长枝木蓼叶片的叶绿素含量降幅大于刺叶锦鸡儿。因膜系统的过氧化作用,使MDA含量升高。轻度干旱胁迫提高了两种野生灌木对盐胁迫的耐受能力。两种灌木能很好地适应中度交叉胁迫,重度交叉胁迫对两种灌木的伤害很大,但也能生存。综合比较各参数发现,刺叶锦鸡儿更耐早,而长枝木蓼更耐盐;综合比较各生理参数发现,刺叶锦鸡儿对干旱和盐胁迫的耐受能力较长枝木蓼强。     

假酸浆种子发芽特性研究

在不同温度、不同贮藏时间和方法下,对来源于印度尼西亚的假酸浆种子发芽特性进行研究。结果表明:不同温度对假酸浆种子萌发的影响差异极显著,在15/25℃变温条件下种子发芽率最高,为84.3%,发芽快且整齐;假酸浆种子采收后立即播种其发芽率非常低,室温下贮藏6～9个月时在25℃恒温或15/25℃变温条件下均有较高发芽率,说明假酸浆种子有休眠性,通过延长贮藏时间能打破休眠,促进种子发芽;但室温贮藏15个月后,种子活力下降非常明显。低温冷藏在一定条件下能提高假酸浆种子萌发能力,能延长种子寿命。     

冷层积和室温干燥贮藏对河西走廊8种荒漠植物种子萌发的影响

不同贮藏和处理条件对不同植物的种子萌发有不同的影响。该文以河西走廊干旱半干旱区8种荒漠植物为研究对象, 探讨了种子经历不同冷层积(4 ℃、-5 ℃、-26 - 10 ℃)和室温干燥贮藏后的萌发响应。研究结果表明: 1)冷层积可使种子萌发率提高、保持不变或降低, 冷层积的有效温度下界可降至-5 ℃或更低。4 ℃和-5 ℃的冷层积使多裂骆驼蓬(Peganum multisectum)和驼蹄瓣(Zygophyllum fabago)种子的萌发率升高、萌发速度加快, 冬季过低的气温以及较大的温度变幅(-26 - 10 ℃)使部分种子萌发率升高。3种冷层积和室温干燥贮藏使黑果枸杞(Lycium ruthenicum)种子萌发率达到90%-100%。唐古特白刺(Nitraria tangutorum)、甘草(Glycyrrhiza uralensis)、苦马豆(Sphaerophysa salsula)种子经过3种冷层积和室温干燥贮藏后萌发率变化较小。中亚紫菀木(Asterothamnus centrali-asiaticus)种子对各种贮藏条件的响应不明显, 部分种子活性丢失。刺沙蓬(Salsola ruthenica)种子扩散时有较高的萌发率(84%), 经-5 ℃和-26 - 10 ℃冷贮藏后, 种子仍具有较高的萌发率, 经4 ℃冷贮藏后几乎不萌发, 大部分种子活性丢失。2)不同物种的种子经过不同方式的贮藏后, 萌发对温度的响应不同。经冷层积后的多裂骆驼蓬种子萌发响应于恒温, 驼蹄瓣和刺沙蓬种子萌发更加响应于变温条件; 多数植物种子在变温培养下萌发速度慢于恒温下。     

画眉草种子萌发对策及生态适应性

研究了画眉草种子在不同贮藏条件以及光照、温度和降雨等环境因素下的萌发对策.结果表明,画眉草新种子具有较强的内在休眠;4个月的干藏和冷藏处理对解除种子休眠作用不明显,但较长时间的贮藏（干藏1年）则能促进种子成熟.画眉草种子在光照和黑暗条件下都能萌发,但较强的光照更有利于种子萌发.种子萌发适宜温度是28 ℃,温度升高和降低都会导致画眉草种子萌发率下降;变温条件下（16～28 ℃）种子萌发率高于恒温28 ℃条件,但两个处理间的萌发率没有显著差异.种子萌发降雨阈值是10 mm,种子萌发率和萌发持续时间均随降雨量的增加而增加.画眉草种子具有迅速萌发和推迟萌发时间超过1年以上两种萌发对策.根据种子形态特征和萌发策略,推断画眉草具有持久土壤种子库.     

喀什霸王的结实和种子萌发特性

喀什霸王(Zygophyllum kaschgaricum)是生长于中国新疆南部荒漠环境的稀有种及二级保护植物。当前, 该物种在自然种群中呈分散式及片段化分布, 且种群密度低, 种群老龄化较严重。因此, 为了了解该物种种子萌发特性及其对荒漠环境的响应, 该文采用室内控制实验方法, 对该物种的自然坐果率、结籽率、种子吸水特性、种子休眠和萌发特性及对干旱胁迫的响应进行了比较研究。结果表明: 喀什霸王在自然种群中的坐果率及结籽率较低, 且种子的败育率较高。不同干藏时间种子的吸水速率间存在显著差异; 随着干藏时间的延长, 种子的吸水率逐步增强。刚成熟的种子在不同温度及光周期下均可萌发; 其中高温(10/20 ℃, 20/30 ℃)及黑暗条件下的萌发率比低温(10/5 ℃, 5/2 ℃)及光照条件下的萌发率高。不同干藏时间的种子在不同浓度赤霉素(GA₃)下的萌发率均较高; 但低温储藏时间对该物种种子的打破休眠及萌发率没有促进作用。以上结果说明该物种存在非深度生理休眠; 而干藏时间、高温且黑暗及高浓度(50 mmoloL ^-1) GA₃是打破休眠及促进种子萌发的最合适条件。高温条件下的干旱胁迫对喀什霸王种子萌发具有抑制作用; 春季和秋季降水量决定种子的萌发率。总之, 喀什霸王种子在物候上表现出的春秋季萌动及非深度生理休眠以提高幼苗存活力及保障种群稳定性, 是一种对新疆南部干旱及高温胁迫荒漠环境的适应策略。     

贵州毕节喀斯特地区优势植物种子萌发特性初步研究

对采自贵州毕节地区的11种植物的种子萌发特性进行了初步研究,结果表明：①盐肤木、火棘、化香、云贵金丝桃与白栎种子在4周之内能够萌发;除云贵鹅耳枥胚坏死之外（萌发实验前后对种子进行解剖）,其他5种植物的种子都未萌发,处于不同的休眠状态。②盐肤木、化香、云贵金丝桃的种子光照时的萌发率远高于黑暗时的萌发率,具有显著差异,尤其是云贵金丝桃,因此3种植物种子均属于喜光性种子;而火棘与白栎种子有无光照都可以萌发,而且萌发率没显著差异,因此属于光不敏感或光中性种子。③盐肤木、云贵金丝桃的种子在30℃较高温条件下萌发最好;白栎、火棘种子在15℃、20℃低温条件下萌发更好;化香种子萌发温度既不能低于20℃也不能高于25℃。④刺异叶花椒种子吸水率高达85%,胚包埋在胚乳之中非常微小、未分化,因此可以初步判定属于形态休眠或者形态生理休眠;而平枝荀子、西域旌节花、云南旌节花种子吸水率都在20%以上,胚长/种子长都超多1/2,并且胚已发育完全,应属于生理休眠;小果蔷薇种子吸水率约27%,胚长/种子长都达2/3,并且通过对种子的解剖发现胚还未发育,应属于形态生理休眠。     

喀什霸王的结实和种子萌发特性

喀什霸王(Zygophyllum kaschgaricum)是生长于中国新疆南部荒漠环境的稀有种及二级保护植物。当前,该物种在自然种群中呈分散式及片段化分布,且种群密度低,种群老龄化较严重。因此,为了了解该物种种子萌发特性及其对荒漠环境的响应,该文采用室内控制实验方法,对该物种的自然坐果率、结籽率、种子吸水特性、种子休眠和萌发特性及对干旱胁迫的响应进行了比较研究。结果表明:喀什霸王在自然种群中的坐果率及结籽率较低,且种子的败育率较高。不同干藏时间种子的吸水速率间存在显著差异;随着干藏时间的延长,种子的吸水率逐步增强。刚成熟的种子在不同温度及光周期下均可萌发;其中高温(10/20℃, 20/30℃)及黑暗条件下的萌发率比低温(10/5℃, 5/2℃)及光照条件下的萌发率高。不同干藏时间的种子在不同浓度赤霉素(GA3)下的萌发率均较高;但低温储藏时间对该物种种子的打破休眠及萌发率没有促进作用。以上结果说明该物种存在非深度生理休眠;而干藏时间、高温且黑暗及高浓度(50 mmol·L–1) GA3是打破休眠及促进种子萌发的最合适条件。高温条件下的干旱胁迫对喀什霸王种子萌发具有抑制作用;春季和秋季降水量决定种子的萌发率。总之,喀什霸王种子在物候上表现出的春秋季萌动及非深度生理休眠以提高幼苗存活力及保障种群稳定性,是一种对新疆南部干旱及高温胁迫荒漠环境的适应策略。     

泡果沙拐枣种子在原生境休眠状态的变化

研究种子在原生境休眠状态的变化,有助于了解种子萌发时机和休眠解除在自然条件下是如何被控制的。泡果沙拐枣(Calligonum junceum)是蓼科沙拐枣属的超旱生灌木,是达坂城荒漠的优势种,是荒漠地区植被恢复重要的候选植物种。于2015年7月,将鲜种子埋放在达坂城自然群落的地表和土中(3~5 cm),定期取回(第1年每6周取一次,第2年每8周取一次,直至2017年9月),在模拟原生境生长季4个变温(15/5、20/10、25/15、30/15℃)下培养萌发。结果表明:成熟的鲜种子在4个温度下萌发率很低,说明种子具有初生休眠;大部分种子具有非深度和中度两种水平的生理休眠;种子的休眠在晚秋和冬季以及来年春季得以解除;3月取出的种子萌发率较高;在夏季高温时节,大部分种子(70%)再次进入次生休眠;在达坂城原生境,泡果沙拐枣的种子处于休眠/非休眠循环,这与达坂城季节性水、热条件的变化及长期大风有关;埋放于土中种子的萌发率高于地表,冬季降雪时地表种子的萌发率高于土中,这与不同部位土壤温度和湿度的波动幅度不同有关。     

松嫩平原碱化草甸恢复演替系列的群落种子流分析

对松嫩平原碱化草甸恢复演替系列4个群落优势种种子源库、土壤种子库及幼苗库进行了比较,建立了种子流模型.结果表明:演替初期虎尾草群落优势种种子源库密度最大,为(446182±180455)粒.m-2,分别是演替中期星星草群落的7.2倍、演替后期星星草 羊草群落的11.4倍、演替顶极羊草群落的164.8倍.土壤种子库和幼苗库密度均以虎尾草群落最大,分别为(63650±14541)粒.m-2和(39160±15192)株.m-2,羊草群落最小,分别为(14310±7686)粒.m-2和(790±745)株.m-2,大体呈随着恢复演替进程而递减的趋势.全体演替系列群落输出的实生苗均以虎尾草为主,占79.8%～100%.在种子流中,优势种的种子源库向土壤种子库输入率在10%～35%之间,输出率差异则较大,虎尾草群落高达62.3%,但星星草群落和羊草群落均没有优势种的幼苗输出.     

GERMINATION ECOPHYSIOLOGY OF ARENARIA GLABRA,A WINTER ANNUAL OF SANDSTONE AND GRANITE OUTCROPS OF SOUTHEASTERN UNITED STATES

The germination ecophysiology of Arenaria glabra Michx., a characteristic winter annual plant species of granite and sandstone outcrops of southeastern United States, was investigated. Seeds germinate in early autumn, plants overwinter in the rosette stage and then flower, set seeds, and die in late spring; seeds are dispersed soon after maturity. Eighty-five to 90% of freshly-matured seeds were innately dormant, and the other 10–15% germinated only at temperatures lower than those that occur in the habitat at the time of seed dispersal in June. During the summer after-ripening period, seeds stored dry under ambient laboratory conditions exhibited progressive increases in rates and total percentages of germination, a widening of the temperature range for germination, and a loss of the light requirement. At a 14-hr daily photoperiod, seeds kept on continuously moist soil germinated to 83% at simulated July and August temperatures during July and August, and the remainder germinated at September temperatures in September. On the other hand, seeds subjected to alternate wetting and drying during July and August germinated to only 9% during those 2 months, and the remainder germinated after the soil was kept continuously moist, beginning on 1 September, at simulated habitat temperatures during September and October. Thus, the timing of germination of A. glabra in the field is controlled by an interplay of the seeds' physiological state with the dynamics of temperature and soil moisture conditions.     

Seed dispersal and seed banks in Aloe marlothii (Asphodelaceae)

Aloe marlothii flowers during dry winter months (July–September) and produces large numbers of wind dispersed seeds. Fire disturbance in a population of several thousand A. marlothii plants at Suikerbosrand Nature Reserve, Gauteng, permitted a series of seed dispersal experiments to be conducted. Germination trials indicated that seedling emergence decreased with increased distance from a well defined aloe stand and burn area margin, with seeds dispersed up to 25 m. Flowering frequency and total seed production were positively correlated with plant height, with seed production estimated to range from 26,000 to 375,000 seeds/plant. Although a large number of seeds are produced by flowering plants the survival rate of seeds did not extend beyond the following flowering season.     

GERMINATION ECOLOGY OF PHACELIA DUBIA VAR. DUBIA IN TENNESSEE GLADES

The germination characteristics of a population of the winter annual Phacelia dubia (L.) Trel. var. dubia from the middle Tennessee cedar glades were investigated in an attempt to define the factor(s) regulating germination in nature. Factors considered were changes in physiological response of the seeds (after-ripening), temperature, age, light and darkness, and soil moisture. At seed dispersal (late May to early June), approximately 50 % of the seeds were non-dormant but, would germinate only at low temperatures (10–15 C). As the seeds aged from June to September, there was an increase in rate and total percent of germination at 10, 15, and 20 C, and the maximum temperature for germination increased to 25 C. Little or no germination occurred at the June, July, and August temperatures in 0- to 2-month-old seeds, even in seeds on soil that was kept continuously moist during this 3-month period. At the September, October, and November temperatures 3- to 5-month-old seeds germinated to high percentages. In all experiments seeds germinated better at a 14-hr photoperiod than in constant darkness. Inability of 0- to 2-month-old seeds to germinate at high summer temperatures allows P. dubia dubia to pass the dry summer in the seed stage, while increase in optimum and maximum temperatures for germination during the summer permits seeds to germinate in late summer and early fall when conditions are favorable for seedling survival and eventual maturation.     

Seed Dormancy,Seedling Establishment and Dynamics of the Soil Seed Bank of Stipa bungeana (Poaceae) on the Loess Plateau of Northwestern China

Studying seed dormancy and its consequent effect can provide important information for vegetation restoration and management. The present study investigated seed dormancy, seedling emergence and seed survival in the soil seed bank of Stipa bungeana, a grass species used in restoration of degraded land on the Loess Plateau in northwest China. Dormancy of fresh seeds was determined by incubation of seeds over a range of temperatures in both light and dark. Seed germination was evaluated after mechanical removal of palea and lemma (hulls), chemical scarification and dry storage. Fresh and one-year-stored seeds were sown in the field, and seedling emergence was monitored weekly for 8 weeks. Furthermore, seeds were buried at different soil depths, and then retrieved every 1 or 2 months to determine seed dormancy and seed viability in the laboratory. Fresh seeds (caryopses enclosed by palea and lemma) had non-deep physiological dormancy. Removal of palea and lemma, chemical scarification, dry storage (afterripening), gibberellin (GA₃) and potassium nitrate (KNO₃) significantly improved germination. Dormancy was completely released by removal of the hulls, but seeds on which hulls were put back to their original position germinated to only 46%. Pretreatment of seeds with a 30% NaOH solution for 60 min increased germination from 25% to 82%. Speed of seedling emergence from fresh seeds was significantly lower than that of seeds stored for 1 year. However, final percentage of seedling emergence did not differ significantly for seeds sown at depths of 0 and 1 cm. Most fresh seeds of S. bungeana buried in the field in early July either had germinated or lost viability by September. All seeds buried at a depth of 5 cm had lost viability after 5 months, whereas 12% and 4% seeds of those sown on the soil surface were viable after 5 and 12 months, respectively.     

Can forest fragmentation disrupt a conditional mutualism? A case from central Amazon

This is the first study to investigate whether scatter-hoarding behavior, a conditional mutualism, can be disrupted by forest fragmentation. We examined whether acouchies (Myoprocta acouchy, Rodentia) and agoutis (Dasyprocta leporina, Rodentia) changed scatter-hoarding behavior toward seeds of Astrocaryum aculeatum (Arecaceae) as a consequence of a decrease in forest-patch area. Our study was conducted at the 30-year-old Biological Dynamics of Forest Fragments Project, in central Amazon, Brazil. We tested whether forest size affected the number of Astrocaryum seeds removed and scatter-hoarded (and likely dispersed) by acouchies and agoutis, as well as the distance that the seeds were hoarded. The study extended over three seasons: the peak of the rainy season (March–April), the transition between the rainy and the dry season (May–June), and the peak of the dry season (August–September). Our results revealed that the number of seeds removed was larger in smaller fragments, but that the percentage of seeds hoarded was much lower, and seeds eaten much higher, in 1-ha fragments. Moreover, fewer seeds were taken longer distances in fragments than in the continuous forest. Site affected the number of seeds removed and season affected the percentage of seeds hoarded: more seeds were removed from stations in one site than in two others, and hoarding was more important in April and September than in June. Our study reveals that scatter-hoarding behavior is affected by forest fragmentation, with the most important disruption in very small fragments. Fragmentation converts a largely mutualistic relationship between the rodents and this palm in large forest patches into seed predation in small fragments.     

The effects of time of seed production on the germination response of Spergularia marina

Germination studies were carried out with seeds of Spergularia marina L. Griseb produced over an interval of six months (June-November). The response of the seeds to light and dark, various constant and alternating temperature regimes, and salinity were determined. In addition, the effects of soil moisture status at the time of seed production on the subsequent germination response of seeds were also determined. Light was an absolute requirement for germination. While a constant temperature regime did not generally favour germination of seed of any month, alternating temperature greatly enhanced germination with an optimum at 5/15°C in all seeds. When imbibed in solutions of different salinities, seeds collected in July and October behaved like true halophyte seeds whereas those collected in June. August, September and November behaved like glycophyte seeds.
High concentration of gibberellic acid (3 000 μ M ) stimulated dark germination in the June and November seed lots, but in light, low GA3 concentration (300 μ M ) stimulated germination most. The addition of kinetin (30 μ M ) plus gibberellic acid enhanced germination in the dark in contrast to GA3 alone; kinetin alone stimulated a very low percentage germination.
The moisture status of the soil at the time seeds were produced did not affect the germination response of an early seed crop (July) but affected that of the later seeds (August).
Judging from the different germination responses, it appears that the seeds belong to at least two physiological groups, one which appears to need either a dark-wet or cold-wet pretreatmem for high germination to occur; and the other group which does not need pretreatmem. The ecological significance of these varied responses is discussed in relation to the survival of the species in its habitat.     

Psychotria hoffmansegiana (Willd ex Roem. & Schult.) Mull. Arg. and Palicourea marcagravii st. Hil. (Rubiaceae): potential for forming soil seed banks in a brazilian Cerrado.

The germinability of artificially buried Psychotria hoffmansegiana and Palicourea marcagravii seeds in Cerrado soil was tested, with the aim of evaluating whether dispersed seeds may be able to form a soil seed bank. The assays were carried out at a Cerrado Reserve in S?o Paulo State, Brazil. Seed samples were placed in nylon bags and buried at two different depths and in two different sites. Samples were periodically exhumed and germination tests were performed with both exhumed and dry stored seeds. In general, soil storage favoured seed survival and germination when compared to dry stored seeds. The seed germination was little affected by soil depth and by burial environment. Seeds of both species remained viable for at least 13 months, considering the time lapse between the collection and the end of the germination tests. It was suggested that both species can potentially form a persistent soil seed bank in Cerrado.     

Seed set in Guayule (Parthenium argentatum,asteraceae) in relation to insect pollination

Guayule (Tarthenium argentatum, Asteraceae) is one of two major plant species grown for natural rubber. Studies were conducted to determine the effect of honey bee (Apis mellifera) pollination and season on seed set and total seed yield/ha. The experiments involved four pollination treatments: plants caged with bees; plants caged without bees; plants open pollinated (uncovered); and plants individually covered. Seeds were harvested monthly July–September 1984, and May–September 1985. Plots with bees produced at least 150% more seeds than plots without bees, and there were no qualitative differences in the seed weights among treatments. Highest seed yield was in May and September. Results indicate that (1) insect pollination in guayule increases seed yield and (2) fewer seeds are produced in the warmest months.     

Some Morphological and Chemical Characteristics of Developing Fruits of Raphia hookeri

Ndon, B. A. 1985. Some morphological and chemical characteristicsof developing fruits of Raphia hookeri.—J. exp. Bot. 36:1817–1830. Fruits which were at different stages of development were randomlysampled from different inflorescences of Raphia hookeri palms.The morphological characteristics and chemical (the dry matter,lipid and carbohydrate) contents of the exocarp and seeds weredetermined. The results showed that the seed length, circumferenceand volume were optimal at 24 months after pollination whichindicates that Raphia seeds attained maximum size at that period.The seed endosperm was liquid or semi-liquid between 6–18months after pollination but became solid with a prominent embryoat 24 months. The seed dry matter was low at the early stagesof development but there was a rapid increase in seed dry weightat 18–33 months after pollination. The seeds were physiologicallymatured at 30–33 months after pollination, while the exocarpmatured at 24–30 months after pollination. The Raphia seeds were low in lipid (about 2%) compared to theexocarp which had 30–40% lipid at full maturity. Maximumamount of lipid was accumulated within the exocarp at 36–42months after pollination and this period indicates the timefor harvesting Raphia fruits for maximum oil which is probablythe most economic part of the fruit. The total sugar concentration increased in the exocarp withincrease in maturity. Conversely the concentration of sugarsdecreased within the seeds as the fruit matured. Maximum totalsugar concentration (about 309 mg g^–1 dry fat free sample)was found in the exocarp at 36–42 months after pollination.Mature seeds at 48 months after pollination had about 50 mgof total sugars per g of fat free sample. There was insignificantaccumulation of starch in the exocarp. The mature seeds werelow in starch (5–10% of the dry weight). Key words: Raphia hookeri, development, fruit