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1.
Prunus cerasoides has poor regeneration in its natural habitat due to its hard seed coat. The information about maturity time of fruit/seed
is scanty and studies on seed germination enhancement lacking. In the present study, the main focus has been given to the
physical fruits/seeds attributes which are reliable indicators of maturity and seed pretreatments which help to enhance germination.
The fruits/seeds were collected from low and high elevational sites covering the altitudinal range of the species during the
period of fruit/seed development (last week of February–mid April) for two consecutive years (2003–2004). The change in fruit
colour from dark green to pale red or red was a useful indicator of seed maturity in P. cerasoides. Fruit moisture content between 46.57 ± 0.45% and 56.81 ± 1.14% and seed moisture content between 29.8 ± 1.35% and 34.13 ± 1.50%
coincided with maximum germination (41.11 ± 13.96% and 59.99 ± 12.05%) across sites. The removal of seed coat (mechanical
treatment) enhanced the germination of seeds to 70 ± 0% at low elevation and 100 ± 0% at high elevation in comparison of control
or untreated seeds (germination range between 5.83 ± 0.83% and 31.68 ± 25.02%). Positive correlation existed between seed
size and germination (r = 0.280; P < 0.01). 相似文献
2.
Myrica esculenta, Buch-Ham. Ex. D.Don is a common under-canopy associate of chir pine and banj oak forests in the Kumaun and Garhwal Himalayas.
The species commonly known as Kaiphal is a small moderate sized evergreen dioecious tree. The species is well known for its
edible fruit and other by products and has emerged as a potential income generating species in the Kumaun and Garhwal region.
The regeneration of Myrica esculenta is poor in natural habitats mainly due to intense anthropogenic pressure on it. To synchronize artificial regeneration of
such species exact knowledge of maturity time is essential to avoid the collection of immature and non-viable seeds. Fruits
of Myrica esculenta were collected from nine sites varying from lower, mid and high range of species distribution (900–2,100 masl) for assessing
seed maturation indicators. Across all the sites the colour change from green to dark red/blackish red appears as one of the
indicator of maturity. In addition to the colour change seed maturity and maximum germination was found in seeds when the
weight of 100 fruits was between 41 and 60 g, fruit moisture content between 62 and 69% and seed moisture content between
30 and 32%. 相似文献
3.
Seed maturity indices of Populus ciliata were investigated in collections from Sukhatal and Bhowali. Across both seed sources, mean capsule size varied from 68.0±1.5 mm2 to 72.0±0.9 mm2, while mean number of capsules/100 grams varied from 268±8 to 295±12. Mean weight of 100 capsules varied from 25.0±1.4 g to 27.0±1.4 g. Weight of 100 capsules among sources and individual trees differed significantly (P < 0.05), while number of capsules/100 grams and weight of 100 capsules was negatively correlated (r2 = 0.69). As capsules matured moisture content decreased from 83.2±1.1% to 54.3±0.3% at Sukhatal and from 77.7±0.4% to 46.4±0.3% at Bhowali. The optimum germination was at 58–60% moisture content. Maturation was related to capsule colour changes as well as moisture content. These parameters were judged to be good indicators of when to collect P. ciliata seeds. 相似文献
4.
自然脱水过程中七叶树种子生理特性的变化 总被引：1，自引：0，他引：1
于 2003 年研究了自然脱水过程中七叶树种子生理特性的变化。结果表明:七叶树种子对脱水高度敏感,为顽拗性种子。种子成熟采收时含水量高达 60.3%,种子在室温下自然干燥 30 天后,含水量下降到 30.2%,此时种子生活力完全丧失。在脱水初期,种子发芽率有所上升,但随后种子发芽率迅速降低。随着含水量的下降,种子浸出液相对电导率上升,但当含水量在 53.7% 到 50.9%之间时,种子浸出液相对电导率出现异常升高。同时种子超氧化物歧化酶(SOD)的活性随脱水时间的延长而下降,只有种子含水量在 53.7% 到 50.9%之间时出现例外。丙二醛(MDA)含量在脱水初期缓慢上升,在含水量下降到低于 50.9%时,丙二醛(MDA)含量快速上升。可溶性糖含量随脱水时间的延长缓慢上升。当种子含水量为 47%–60%时,种子发芽率较高,说明这一含水量区间有利于种子生活力的保持。图 6 参 13。 相似文献
5.
We investigated the effect of provenance variation on cone and seed morphology and germination behaviour under different pre- treatments in Picea smithiana. Three categories of cones were recognized: large (13.18 cm × 3.30 cm 15.42 cm × 4.35 cm), medium (10.85 cm × 3.93 cm 12.18 cm × 3.98 cm) and small (7.69 cm × 3.06 10.98 cm× 3.39 cm). Significant variation was observed for various cone and seed characteristics. Seeds moisture content varied from 44.48% to 56.91%, seed size from 0.64 cm × 0.31 cm (largest seed) to 0.49 cm × 0.10 cm (smallest seed), and the seed weight from 2.45 g per 100 seeds to 1.36 g per 100 seeds on fresh weight basis of P. smithiana. The highest seed germination (72.0±7.53%) at 10°C was observed under chilling treatment in Tapovan provenance, while the minimum (15.0±5.71%) seed germina- tion was recorded at 25°C under control set in Tapovan provenance. Further among all the sources Pandukeshwar consistently had the highest average (38%) percent germination across all treatments. Compared to other temperature regimes and pretreatments, seeds subjected to 10°C and chilling treatment had the highest germination and took the least time for germination irrespective of provenance effects. Altitude (provenance) had little or no relationship with germination following laboratory treat- ments. Seeds from Tapovan provenance subjected at 10°C following chilling treatment may be suggested for further multiplication of this species. 相似文献
6.
《Scandinavian Journal of Forest Research》2012,27(4):273-279
Abstract The response of common alder [Alnus glutinosa (L.) Gaertn.] and downy birch (Betula pubescens Ehrh.) seeds to germination temperature was examined following chilling and priming. Seeds of two seed lots of each species were subjected to combinations of chilling (4±1°C) and priming (20°C) treatments in fully imbibed (FI) state or a lower target seed moisture content (TMC) level (30% and 35% in alder and birch, respectively). After treatment, the seeds were allowed to germinate for 56 days at constant temperatures of 7.5, 10, 15, 20, 25 or 30°C. The response to temperature and pretreatment differed between species, but the effect was consistent in each seed lot within each species. In alder, the TMC seeds germinated well across the full range of temperatures, whereas there was an optimum temperature (22–23°C) for seeds given the FI pretreatment. Priming had no significant effect on the germination response of the TMC seeds in alder, but priming greatly improved germination in the FI seeds, especially at the lower germination temperatures (optimum 18–19°C). In contrast, in birch, the TMC seeds germinated better across the full temperature range, but the optimal germination temperature (15°C) was the same for all seed pretreatments. Priming improved germination in both the FI and TMC seeds in birch. 相似文献
7.
为探究华中樱桃 Cerasus conradinae种子生物学特性,以 湖北省赤壁市的野生华中樱桃的自然成熟未落地的果实为试验 材料,观察其种子形态,并测定种子长度、宽度、厚度、千粒 重、吸水特性和发芽特性。结果表明：华中樱桃种子为卵形,长 7.64±0.73mm,宽5.28±0.55mm,厚4.39±0.47mm,千粒重 62.77±2.91g,属中粒种子;种子浸种0~4 h吸水较快,后渐趋 缓,浸种24 h近饱和,吸水率为33.23%,种子饱和状态时吸水率 为33.30%;用750 mg/L 赤霉素（GA3）溶液浸种处理的种子发芽 效果较清水浸种好,但差异不明显,两者发芽率分别为65.3%和 62.7%;华中樱桃幼苗个体间差异大。 相似文献
8.
Elissavet Konstantinidou Ioannis Takos Theodora Merou 《European Journal of Forest Research》2008,127(2):125-131
The effect of seed moisture content (m.c.) and seed storage conditions of bay laurel (Laurus nobilis L.) was investigated in relation to seed viability. In the first experiment, the effect of drying rate on seed moisture and
seed germination was investigated. Fresh seeds, with their original moisture content displayed a germination percentage of
55.1%. When the seed moisture content was reduced by 2.0% in an oven, the germination percentage rose to 81.0%. When the seed
moisture content was reduced even more by using the same method, the germination percentages decreased dramatically. Reducing
the seed moisture content to 28.7 and 23.5% by drying the seeds in alternating room conditions resulted in an increase of
seed germinability to 84.3 and 90.9%, respectively. The drying of the seeds for 45, 60 and 75 days reduced their seed germination
to 66.8, 49.4 and 48.0%, respectively. Reducing seed moisture content below 15.0% resulted in practically nullifying seed
germinability. The fact that bay laurel seeds cannot retain their germinability at lower moisture contents demonstrates that
it is a species with recalcitrant seeds. In the second experiment, moist and dry storage conditions were tested under different
temperatures and moisture contents. The storage experiment showed that the most effective way of conserving the bay laurel
seeds is moist storage at 0 ± 1°C for 4 months without previous drying of the seeds. 相似文献
9.
Our study on maturity indices of Aesculus indica Colebr.seeds was conducted under temperate Kashmir conditions in 2006.Seed collection was started from 15 July and continued until the maturation of seeds in December.The seeds were harvested fortnightly from identified trees and on each collection date maturity indices,viz.seed color,seed weight,moisture content,seed dimension,specific gravity and germination percentage were recorded.The study revealed that at the time of maturity (Nov.–Dec.) the seed color ... 相似文献
10.
Charles Parkouda Haby Sanou Abasse Tougiani Adama Korbo Dennis S. Nielsen Kwaku Tano-Debrah Anders R?bild Bréhima Diawara Jan S. Jensen 《Agroforestry Systems》2012,85(3):455-463
The present study was carried out to evaluate variability in fruit characteristics and nutritional quality of Baobab fruits with the aim of providing the background to select trees bearing fruit with desirable characteristics for further utilisation. Vitamin C, total sugar and ash contents were assessed in 178 Baobab fruit samples from 11 sites in Burkina Faso, Mali and Niger. Furthermore the following tree and fruit physical characteristics were recorded: tree height, bark colour, fruit size, pulp weight, seed weight, seed size and pulp colour. The content (mean?±?SD) of vitamin C was 4.78?±?1.02?g?kg?1, sugar 514?±?72?g?kg?1 and fruit weight 293?±?96?g. There was a significant correlation between annual precipitation of the tree population site and vitamin C content but not with sugar content. For sugar, there were significant positive correlations with latitude and longitude. Negative correlations were found between fruit size and both longitude and latitude with smaller fruits generally being found to the north/east. No relation was found between pulp or bark colour and the sugar or vitamin C content. The contents of protein, lipid, carbohydrates, ash and moisture in the seeds ranged from 156 to 159, 143 to 150, 641 to 652, 44 to 49 and 50 to 55.7?g?kg?1 respectively. The variation for vitamin C and sugar found within populations is a first indication that valuable gains could be made by selection of superior trees. 相似文献
11.
V. Sivakumar R. Anandalakshmi R. R. Warrier M. Tigabu P. C. Odén S. N. Vijayachandran S. Geetha B. G. Singh 《New Forests》2006,32(2):121-131
Seeds of Strychnos nux-vomica have slow and erratic germination; thus different presowing treatments were applied to enhance the germination of its seeds
collected from Tamaraikulam, Tamil Nadu, India. In addition, the effects of desiccation and different storage conditions on
the germination of S. nux-vomica seeds were investigated. The results show that soaking in 500 ppm gibberellic acid (GA3) for 24 h, incubation of seeds at 40 °C for 3 days and alternate water soaking (16 h) and drying (8 h) for 14 days significantly
increased the percentage germination compared to the control. Desiccation of seeds down to 10% moisture content resulted in
better germination. Germination of S. nux-vomica seeds differed significantly between different storage periods, moisture contents of the seed and for first and second order
interactions (p<0.001). The highest germination (92%) was achieved when seeds with 10% moisture content were stored at ambient temperature
for 30 weeks. Evidence from the present study indicates that S. nux-vomica seeds possess physiological dormancy that can be broken effectively by after-ripening. As seeds of S. nux-vomica are found to be desiccation tolerant, dry seed (10% moisture content) can be hermitically stored at ambient temperature for
30 weeks without losing their viability. 相似文献
12.
Seeds of Celtis australis were collected from 13 different sources, ranging from 550 to 1980 masl, in Central Himalaya, India. Significant (p = 0.05) variations were observed for seed traits among provenances. However, among various characters, seed weight exhibited
maximum variation between seed populations compared to other morphological characters. Between provenances, seed weight ranged
from 47.8 to 83.1 g/1000 seed, with mean value of 66.9 ± 10.7 g/1000 seed. Significant (p = 0.01) positive correlation was found between morphological characters of seeds including seed weight and elevational range
of seed source. For one year old seedlings, average shoot and root growth was 61.1 ± 13.3 and 30.5 ± 5.4 cm, respectively,
irrespective of provenance variation. Inter-comparing biomass yield of the seedlings with altitude, average biomass production
was 8.4 ± 2.5, 9.4 ± 3.3 and 12.7 ± 1.7 g/plant, respectively, for low (550–1000 masl), middle (1050–1250 masl) and high (1350–1980 masl)
altitudinal populations. Significant (p = 0.01) positive correlation between growth performance of seedlings and altitude of the seed source was recorded. Across
the provenances, shoots had the highest proportion of total biomass (42.3%), followed by leaves (32.6%) and roots (24.6%).
Among various provenances, Badiyargaon, Agroda, Guptakashi, Jakholi, Gajeli, Srinagar and Palampur populations produced heavier
seedlings and grew faster compared to seedlings of other sources. 相似文献
13.
Seeds of Juniperus procera collected from five provenances across its geographic range in Ethiopia were subjected to cold-moist stratification at 5°C
or 10°C for 6–12 weeks. The effect of aqueous smoke solution in overcoming the light requirement for germination, and the
potential of visible (VIS) and near infrared reflectance (NIR) spectroscopy for sorting sound and insect-damaged seeds were
also investigated. Highly significant differences in germination were detected among provenances (P < 0.0001) and stratification periods (P < 0.0001), but not between temperature regimes (P=0.111). Seeds from the south and southeast distribution ranges had higher percentage germination after 6 weeks of stratification
than seeds collected from north, northwest and central ranges of distribution. The smoke treatment did not affect germination
regardless of whether the seeds were exposed to light. Exposure to light increased germination capacity three fold. Sound
and damaged seeds were distinguished with 90% accuracy using VIS + NIR spectroscopy. It can be concluded that dormancy in
juniper seeds varies with provenances, and cold stratification for 6 weeks alleviates dormancy in some seed lots. Tentatively,
smoke treatment seems ineffective in overcoming photo-dormancy in juniper seeds. VIS + NIR spectroscopy has demonstrated a
great potential for sorting damaged seeds, thereby upgrading seed lot purity. 相似文献
14.
We performed desiccation and storage trials to better under- stand storage behavior of Knema attenuata seeds. Mature seeds with moisture content (MC) of 31% exhibited 73% germination. During the period of desiccation (open lab condition) seeds with MC 23% showed 40% germination. After further drying to MC 21% germination was reduced to 16%. Complete loss in viability resulted when seed moisture was reduced to 18%. The seeds stored at -10°C, 0°C, 10°C and 28±2°C (open lab condition) lost their viability within 10 days. Seeds stored in sealed polythene bags and moist sand retained viability for more days than did seeds stored under all other storage conditions. Sensitivity of seeds to lower temperature and desiccation suggest that the storage be- havior of K. attenuata seeds is recalcitrant. Seeds stored in moist condi- tions can, at best, be stored for a period of two months. 相似文献
15.
Laurel (Laurus nobilis L.) seeds were collected from the west part of Turkey in the fall of 2002. Seeds with pericarp (+) or without pericarp (−)
were treated with 1000 mg/l, 2000 mg/l and 3000 mg/l GA3 concentrations, cold stratified at +4 ± 1°C for 25 and 50 days, punctured and seed coat removed to overcome and assess the
mechanism of laurel seed dormancy. A period of 50 days cold stratification and removing seed coat significantly increased
germination rate to 55% ± 1.91 (Mean ± SE) and 85% ± 3.00, respectively. None of the seeds with pericarp germinated regardless
of treatment they underwent. Results suggested that seed dormancy was mainly due to pericarp and perhaps inhibitors linked
to seed coat. 相似文献
16.
Effects of stratification, desiccation, radicle pruning, and season of sowing on Quercus vulcanica germination and growth were studied to identify optimum nursery procedures for artificial regeneration of this species. Following stratification (0, 2, 4 and 8 weeks), acorns were germinated, and acorn moisture content and germination performance were also determined at various times during desiccation. In early December unsprouted acorns were planted in containers, and in early April sprouted acorns, which had been stored in polyethylene bags at 4 °C, with radicles left intact or with radicles pruned back to 1.0 cm were planted in containers.Stratification for 2 and 4 weeks did not increase germination percentage but significantly increased germination rate. Germination percentage of the seeds dropped when the moisture content of the seeds was reduced by desiccation, and the critical minimum moisture content of the recalcitrant Q. vulcanica acorns was found to be 11–16%. Spring sowing of sprouted acorns altered the morphology the containerized seedlings and caused the formation of significantly more main roots, but resulted in significantly less shoot height and shoot dry weight. Spring-sown sprouted acorns had also a significant advantage over the fall-sown unsprouted acorns in seedling survival, and thus nursery personnel should not be concerned if acorns sprout before sowing. 相似文献
17.
We investigated the morphology and germination of Tamarindus indica seeds in order to discover the effects of variation in seed sources and pre-sowing treatments on germination. The experiment was carried out in the nursery of the Forestry and Wood Technology Discipline, Khulna University, Bangladesh. Seeds were collected from different but healthy trees from various locations in Bangladesh and subjected to four pre-sowing treatments, i.e., control, immersion in cold water (4°C for 24 h), immersion in hot water (80°C for 10 min) and scarification with sand paper. Seed germination was carried out in poly-bags with a mixture of topsoil and cow dung in the ratio of 3:1. The average length of the fresh seeds was 1.35±0.26 cm, their width 1.07 ±0.20 cm and thickness 0.69±0.11 cm. The results revealed that pre-sowing treatments affected the germination process of seeds, which significantly increased the germination percentage with the cold water (81.67%) and scarification with sand paper (82.33%) treatments, compared with those in the control (58.33%) and hot water treatment (59.00%). In all treatments germination started on average within 5 to 7 days after the start of the treatments and were completed from 13 to 19 days later. The greatest success in germination (82.33%) was found in scarification with sand paper, followed with 81.67% in the cold water treatment. The results of analyses of variance (ANOVA) showed significant differences (p<0.05) in germination closing dates, seed germination periods and germination percentages among the treatments but no significant difference among seed sources. However, the effect of the interaction between seed source variation and pre-treatment differed significantly in seed germination closing dates and germination percentages. We recommend cold water treatment (submersion of seed at a temperature of 4°C for a 24-h period) for seed germination of T. indica in rural Bangladesh. 相似文献
18.
Poor seed germination is a significant problem for propagation of teak and it particularly hampers the deployment of genetically improved material into plantations. Seed dormancy is the putative cause for delayed and sporadic germination of teak seed but specific dormancy mechanisms have not been proven. In this paper we investigate whether physical or mechanical dormancy could affect teak germination. Physical dormancy was disproved when we observed water in every examined locule of fruit which had been immersed for 12–24 h (n = 1,700 fruits from six diverse sources). Mechanical dormancy was found to affect teak seed germination by means of valve structures which must open for the radicle to emerge. All 1,450 germinating seeds in 16 samples emerged from the endocarp via the detachment of a valve. Germination over 16 days was compared between extracted seeds (ex situ) and seeds within their endocarp (in situ) to determine the effect of mechanical dormancy on germination. Significantly greater germination of the ex situ seeds (62 ± 2% SE; n = 486) than of the in situ seeds (32 ± 2% SE; n = 564) indicated that mechanical dormancy is an important factor in the poor germination of teak. 相似文献
19.
Truong Mai-Hong Tran D. Hong Nguyen T. Hien Ho H. Hai Tran D. Tung Vo T. Le-Tam Banh Ngoc-Tam Richard H. Ellis 《New Forests》2006,32(1):9-19
Mass maturity (end of the seed-filling phase) occurred at about 72 days after flowering (DAF) in developing seeds of Mimusops elengi, at which time seed moisture content had declined to about 55%. The onset of ability to germinate was detected at 56 DAF
and seeds showed 98% germination by 84 DAF. Tolerance of desiccation to 10% moisture content was first detected at 70 DAF
and was maximal by 84 DAF. Delaying collection by a further 14 days to 98 DAF, when fruits began to be shed, reduced seed
viability, particularly for seeds first dried to 10% moisture content. Hence the best time for seed collection appears to
be about 14 days before fruits shed. In a separate investigation with six different seed lots, desiccation below about 8–12%
moisture content reduced viability (considerably in some lots). The viability of dry seeds (below about 10% moisture content)
stored hermetically was reduced at cool temperatures (5 °C and below), and none survived storage at sub-zero temperatures.
The results suggest that Mimusops elengi shows intermediate seed storage behaviour and that the optimal hermetic seed storage environment is about 10% moisture content
at 10 °C, while short-term, moist, aerated storage at high (40%) moisture content is also feasible. 相似文献
20.
We explored the temporal effects of fruit consumption on the subsequent seed germination pattern of a fleshy-fruited tree, the Chinese hackberry (Celtis sinensis). Via nursery-based sowing experiments, we investigated (1) how pulp removal affected seed germination patterns at the different stages of fruit maturation, and (2) how the timing of seed dispersal (August, October, and December) affected the germination patterns of seeds from ripe fruits after the removal of pulp. We found that the removal of pulp from around the seeds of ripe fruit had no effect on the percentage and timing of germination. In contrast, the removal of pulp from seeds of unripe fruits largely reduced the germination percentage. The time of sowing did not affect the germination percentage, whereas the timing of germination was delayed for seeds that were sown later or under shaded environments. 相似文献