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1.
《Scientia Horticulturae》1986,30(3):203-211
Scanning electron micrographs of the cashew are presented, showing the development of the male and hermaphrodite inflorescences. An unusual feature is the three different lengths of stamens and their role in pollination. Although cashew flowers have many features common to flowers pollinated by insects, few were observed except for ants. Nectar was not detected in many flowers and concentrations varied between selections. These results are discussed in the light of conflicting views of whether anemophily or entomophily is the basic mode of pollination.  相似文献   

2.
Summary

IBA-treated cuttings rooted only when prepared fom bark-ringed shoots. The response to ringing declined with increasing age of the tree. However, on marcotting, the ringed shoots of four year old trees showed more and earlier rooting.  相似文献   

3.
The influence of seed maturity, seed storage and germination pre-treatments on seed germination of cleome (Cleome gynandra L.) were investigated. Seed maturation studies showed that capsules harvested at 18 days after anthesis possessed the highest dry weight with 19.2% moisture and 1% germination. Development of fresh-ungerminated seed was observed with increasing maturity of fruit, suggesting that cleome exhibited forms of seed dormancy. Storing mature seed at 15 °C and at room temperature for 5 months showed that seed dormancy was broken after 3 months under both storage regimes. When mature seeds were subjected to different treatments including various levels of GA3, KNO3, leaching, pre-chilling, soaking and pre-heating at different temperatures, it was found that pre-heating at 40 °C for period of 1–5 days was the most effective method in breaking dormancy in cleome.  相似文献   

4.
Self-incompatibility of almond [Prunus dulcis (Mill.) D.A. Webb] is controlled by the S-locus with 30 described allelic variants. In this study, PCR amplification, cloning and DNA sequence analysis revealed a new S-RNase allele in a Hungarian cultivar, ‘Tétényi bőtermő’. This new allele was labelled as S31. Since S31 is characterized by almost identical intron sizes as S9, consensus PCR was not successful in discrimination of the alleles, even if fluorescently labelled fragments were sized on an automated sequencer. Therefore, an allele-specific forward primer (PdS31-F) was designed to anneal selectively within the second intron of the S31-RNase gene and used in combination with the EM-PC3consRD consensus primer. This allowed for the successful discrimination of S31 from S9. The PdS31-F primer and allele-specific PCR in general might be useful in the identification of different alleles with matching intron sizes that might occur during screening for S-alleles in a more diverse population, e.g. local cultivars from Central Europe to Asia.  相似文献   

5.
Self-sterility in cherry (Prunus avium L.) is one of the most important problems in commercial cherry orchards in Iran and many other countries. The main objective of this research was to determine self-fertility rate and blooming phenology of 25 commercial cherry (P. avium L.) cultivars in Iran. This study was conducted during 2006–2007.Results revealed that the stage of bud swell in all cultivars began late second decade of March, which lasts 8–11 days. In all cultivars the duration end bloom to petal fall stage took 5 days. Cherry cultivars were classified into three groups considering their overlapping pollination. The cultivars each group had a great overlapped pollination toward each other. The results also showed that there was a significant difference among cultivars in respect of the fruit set (P < 1%). The fruit set of open pollination treatment among the cultivars varied in range of 7.36–41.58%. However fruit set was not observed in isolated pollination (artificial and natural self-pollination). In open pollination, the cultivars were also classified into four groups, i.e. weak fertility (Moreau and Ferracida), mean fertility (Siah Mashhad, Napelon, Proteva, Haj usefy, Lambert, Roshun, Sefid Ghermeze Baghno, Arak, Belamarka, Siah Shabestar, Ghermeze Rezaeyeh, Abardeh, Soraty Lavisan and Victoria), good fertility (Peshrase Mashhad, Dovoumras Mashhad, Bing, Shesheiy Mashhad, Siah Ghazvin and Sefid Rezaeyeh), very good fertility (Zarde Daneshkadeh, Dirrase Italia and No. 1 karaj). All cultivars were found to need cross-pollination and included in self-sterile group.  相似文献   

6.
The effects of different types of chitosan on seed germination and protocorm development were determined for two orchid species, Dendrobium bigibbum var. compactum and Dendrobium formosum. Six chitosan types derived from polymer or oligomer chitosan each with 70, 80 or 90% levels of deacetylation (P70, P80, P90, O70, O80 and O90, respectively), were evaluated as direct medium supplements at 0, 10, 20, 40 or 80 mg/L in modified VW medium by following seed germination and protocorm growth for 12 weeks. Chitosan of all six tested types and four concentrations were found to significantly enhance the proportion of D. formosum seeds that germinated, when compared to these germinated without chitosan. In contrast, chitosan caused no enhanced germination rate was noted for D. bigibbum var. compactum with all tested chitosans and doses tested. However, almost all types of chitosan at 10 mg/L, except O90, were able to significantly improve the growth of D. bigibbum var. compactum protocorms, whilst 10 or 20 mg/L of P70 chitosan was the best formula to enhance the growth of D. formosum protocorms. It is concluded that chitosan responses in seed germination and protocorm development were somewhat species and developmental stage dependent. Therefore, the appropriate chitosan application for each plant species should be evaluated first before use.  相似文献   

7.
Embryo development followed by seed germination was investigated in seeds of Christmas rose (Helleborus niger) held under different temperature conditions. The seeds had a heart-shaped embryo when dispersed from parent plants. That embryo developed rapidly to the torpedo stage at 25 °C, after which no further development occurred. When seeds with a torpedo-stage embryo were held at 15 °C, the embryos developed to the cotyledon stage, but no further germination occurred. Similar phenomena in the course of embryo development were observed in seeds held in a non-heated polyethylene house, in which the embryos developed to the torpedo stage at 20 °C or more, while further development to the cotyledon stage was attained only at temperatures of 15 °C or less. Seeds with a cotyledon-stage embryo rarely germinated until they were treated at 4 °C for more than 8 weeks. These results suggest that seeds of H. niger have a deep, simple morphophysiological dormancy caused by the combination of rudimentary embryos and a physiological dormancy that can be broken by cycles of warming and chilling.  相似文献   

8.
Dessert quality of guava fruit is considerably reduced by high seed content. Number of seeds in guava is associated with different seed and fruit characters. Influence of different seed characters on number of seeds per fruit (NSPF) was studied by analysing character association and direct and indirect effects on NSPF and seed related traits for 68 genotypes of guava collected from diverse sources and conserved at National Active Germplasm Site, CISH, Lucknow. Seed related characters were studied at the colour break stage of the fruits using image analysis software for counting number of seeds. The data was subjected to path analysis to find out direct and indirect effects of different characters on number of seeds in the fruits. At genotypic and phenotypic levels, NSPF was significantly and positively associated with seed weight per fruit (SWPF), number of seeds 100 g−1 pulp (NSPHP) and fruit weight (FW). The genotypic (0.0029) and phenotypic (0.0563) residual values were fairly very low, which revealed that variables included in this study had significant contribution in determining NSPF. The NSPHP exhibited high positive direct effect on NSPF. The maximum direct response (P = 0.737, G = 1.004) of this component was attributed to the indirect positive effects of the SWPF and fruit:seed weight proportion (FSWP). SWPF also had a very high positive direct effect (P = 0.521, G = 0.694) on the NSPF. Correlation and path coefficient analysis revealed that SWPF, NSPHP and 100-seed weight (100SW) were deciding factors for realizing improvement for NSPF. The importance of small seeded genotypes in selection of less seeded varieties was emphasized.  相似文献   

9.
Polyamines putatively affect tolerance to abiotic stresses and are believed to be important in organogenesis. Present experiments investigate the relationship between polyamines (PAs) and seed quality. Therefore, during seed development, the changes in free putrescine (Put), spermidine (Spd) and spermine (Spm) and physiological and biochemical parameters in F1 seeds of sh2 sweet corn were compared. Concentrations of Put, Spd and Spm increased from 14 to 30 days after pollination (DAP). After 30 DAP Put concentration declined with an opposite trend to that of Spd and Spm. The regression analysis between PAs and seed quality described by physiological and biochemical parameters including germination percentage, germination energy, germination index, seed size, seed fresh and dry weight, total soluble sugar, total soluble protein, Malondialdehyde (MDA) concentration, electrolyte leakage, peroxidase (POD) and catalase (CAT) activity were conducted. Spd was observed to have a closer relation with the comprehensive physiological changes of seeds during their development than that of Put and Spm. Moreover, the Spm concentration might be more suitable to forecast seed germinability during seed maturation period than Spd and Put. It indicated that endogenous Spd and Spm in dissociated form had more effect than Put during seed development progress of sweet corn.  相似文献   

10.
The germination rate of palm seeds can be improved by pre-treatment of the seed. Several methods proved effective for Euterpe edulis seed, but sulphuric acid immersion and hydrogen peroxide leaching treatments both decreased emergence of germinated seedlings and restricted plant growth up to 6 months after germination.The best overall results in germination and subsequent seedling development were from seed leached in water for 72 hours at 30°C. This treatment can be related to the natural conditions encountered by the seed in the highly leached soils of a tropical rain forest.  相似文献   

11.
The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper.  相似文献   

12.
The accumulation of total phenols (TP, Folin-Ciocalteu method) and total flavonoids (TF, colorimetric assay with AlCl3) and the evolution of antioxidant capacity (FRAP assay, DPPH and ABTS radical scavenging assays) have been monitored in juices of Croatian white cabbage (Brassica oleracea var. capitata) cultivars Vara?dinski and Ogulinski, as well as Chinese cabbage (Brassica rapa var. pekinensis), at various developmental stages. Measurements were performed every four weeks, starting from planting to full maturity, throughout the course of eight months. In the first 8–12 weeks, the TP and TF contents as well as antioxidant capacity increased significantly in all analyzed juice samples and in most even doubled. This rapid increase was followed by a gradual decrease in values derived from all assays, over the course of 12–30 weeks, to the final values which were in all cases lower than the values measured at week 4. The results also point to significant variability in TP and TF contents and antioxidant capacity at the fully mature stage between white and Chinese cabbage juices and between juices extracted from cultivars Ogulinski and Vara?dinski.  相似文献   

13.
Since spring 2011 the roof of a building on the Agripolis Campus of the University of Padova (Italy) has been used as a drainage area for two rain gardens with a circular area of about 10% and 20% of the drainage area respectively. To improve soil infiltration, the topsoil was removed up to the depth of 1 m and filled with a mix of 50% sand, 25% compost and 25% of the existing topsoil. Herbaceous perennials were selected and planted to test their adaptability to different soil water conditions in the rain garden. To evaluate the capacity of each rain garden to manage stormwater runoff a simplified water balance was done, estimating actual evapotranspiration using the WUCOLS method. From autumn 2012 runoff volumes were collected just from one pitch of the roof, and directed only into the smaller rain garden that became equal to 15% of the new roof drainage area. We thus had the possibility to test the functionality of rain gardens with three different percentages of roof drainage area: 10, 15 and 20%, even if in different periods. Results are presented relating to a four-year experimental period. Regarding hydrological behaviour, the input water volumes caused a slight overflow only during a few rainfall events. Consequently, the results showed a high capacity to manage stormwater runoff and also in the smaller rain garden almost the total roof runoff volumes infiltrated into the soil. As regards plants, the results indicated that the growth is affected by their position in the rain garden, from the wettest condition in the centre to the driest at the perimeter, except for Hemerocallis hybrida that showed great adaptability in all positions. Aster novi-belgii, Echinacea purpurea, Iris pseudacorus, Molinia caerulea and Rudbeckia fulgida also showed good adaptation, even if not in all rain garden zones, with highly aesthetic results. Lythrum salicaria and Saponaria officinalis plants appeared to be unsuitable for rain gardens. The results of the experiment have shown that, in the Veneto plain environment, rain gardens with a size of 10–15% of the roof drainage area can ensure both the sustainable management of stormwater runoff and a high aesthetic functionality.  相似文献   

14.
Pogonatherum paniceum (Lam.) Hack. is a rock plant with good potential for vegetative recovery on naked lands. A high frequency in vitro regeneration system was developed for P. paniceum. Calli were induced from explants of mature seeds, seedlings, young leaves, and stem segments on Murashige and Skoog (MS) medium supplemented with 1.0 mg L−1 2,4-dichlorophenoxyacetic acid (2,4-D), 2.0 mg L−1 α-naphthalene acetic acid (NAA) and 0.2 mg L−1 6-benzylaminopurine (BAP). High induction rates (59.57%) and regeneration rates (100%) were obtained from mature seed explants; calli were sub-cultured for over 2 years and still retained a high regenerative capacity. One seed explant resulted in 69,997 plants in 1 year. Shoot buds derived from calli were used for encapsulation in liquid MS medium containing 3% sucrose and two different alginate matrices (3% sodium alginate (w/v) + MS medium containing 3% sucrose and 3% sodium alginate + 1% activated carbon (w/v) + MS medium containing 3% sucrose) with a 20-min exposure to 2% CaCl2 and 0.3% bavistin (w/v). The capsule with 3.0% sodium alginate (w/v) and 1% activated carbon (w/v) showed a higher conversion rate (61.58%) and stronger plantlets under non-aseptic conditions. These systems are useful for the rapid clonal propagation and dissemination of artificial seed material of P. paniceum for eco-recovery.  相似文献   

15.
《Scientia Horticulturae》2005,106(3):318-329
Mycorrhizal fungi serve as biofertilizers, reduce plant stress, and can increase plant productivity. Since the potato originated from the highlands of Peru and Bolivia, a goal of this research was to utilize indigenous Peruvian mycorrhizal populations to enhance crop productivity in a subsistence production site. The field study was also conducted to test the effectiveness of the flavonoid, formononetin, to stimulate native mycorrhizal activity and subsequent yield of six Andean potato (Solanum tuberosum L.) cultivars. The subsistence site was located at an altitude of 3900 m (61 kPa) in San Jose de Aymara (Department of Huancavelica), in the central highlands of Peru. This is approaching the highest altitude in the world that potatoes are grown. The site had a sandy–loam soil with pH 3.6, low phosphorus (P) availability and high aluminum (Al). Tubers were planted in November 1999, and grown during the rainy season. Minimal organic fertilizer was applied and the potato crop received no supplementary irrigation. Formononetin was applied as a soil drench when shoots from tubers began to emerge. At the end of the 6.5 month study, formononetin increased either potato tuber dry mass and/or Nos. 1 and 2 grade tubers in three of the six cultivars. Soil sporulation of indigenous mycorrhizae was increased more than three-fold by formononetin. There were differences in total mycorrhizal colonization among the six cultivars. The predominant arbuscular mycorrhiza genera at the site were Gigaspora, Glomus and Scutellosporas.  相似文献   

16.

Context

Eco-environmental effects of urbanization are a focus in landscape ecology.

Objective

The influences of population, economic and spatial development during the urbanization process in Beijing City, China on net primary productivity (NPP) were analyzed. The responding mechanism of NPP in different urbanization stages was also examined to develop advice about eco-environmental sustainability of urban development.

Methods

Using the Carnegie Ames Stanford Approach model, we estimated NPP. Using linear regression and polynomial regression analysis, we analyzed NPP responses to stages of urbanization.

Results

High NPP areas were located in northeast Yanqing, northwest Miyun, northern Huairou and Pinggu. The distribution of NPP generally occurred in the following order from high NPP to low NPP: outer suburbs, inner suburbs, encircled city center, and inner city. Because of the heat island effect in winter, the estimated NPP in the encircled city center and inner city was higher in 2009 than in 2001. There was a negative correlation between NPP and both economic and spatial urbanization, but an increase in population did not necessarily lead to an immediate decrease in NPP. An analysis of NPP dynamics in five kinds of urban development zones showed that urbanization resulted in a lasting and observable loss of NPP over time and space, although there was some promotion of NPP in highly urbanized zones.

Conclusion

There are three stages in the response of NPP to urbanization: damage stage, antagonistic stage, and coordination stage. The stage threshold depends on local eco-environmental management and urban planning interventions.
  相似文献   

17.
Studies were carried out on the oil content, fatty acids, tocopherols and sterols in the seeds of two carobs (Ceratonia siliqua), cultivated and wild, from Turkey. The oil yields of cultivated and wild carob seeds were established as 1.73 and 1.82% on a dry weight basis, respectively. The main fatty acids in cultivated and wild carob seed oils are linoleic (49.1% and 51.0%), oleic (30.4% and 26.5%), palmitic (10.3% and 12.0%) and stearic (3.5% and 4.6%), respectively. Tocopherols and phytosterols are important constituents of the unsaponifiable fraction of several seed oils. The major tocopherol in both seed oils was γ-tocopherol. The composition (mg/100 g) was as follows α-tocopherol (69.06 and 70.39 mg/100 g), P8 (22.29 and 24.78 mg/100 g), δ-tocopherol (8.70 and 10.66 mg/100 g), β-tocopherol (2.30 and 1.85 mg/100 g). The total tocopherol contents had 208.45 and 223.14 mg/100 g, respectively. The total content of sterols of both oils were determined as 16400.94 and 30191.55 mg/kg, with β-sitosterol as the predominant sterol that accounted for more than 70% of the total amount of sterols other sterols, campesterol (5.33–5.32%), stigmasterol (0.58–11.43%) 7-avenasterol (3.45–3.03%), 7-stigmasterol (2.16–2.4%), and chlerosterol (1.33–1.0%) were detected in both carob oils. As a result, the accurate quantification of these analyses has very important applications for the nutrition sciences.  相似文献   

18.
The genetic diversity of 15 carob (Ceratonia siliqua L.) cultivars located in an experimental field from Algarve (Portugal) was evaluated over 7 years using 12 fruit and seed phenotypic characters, in order to characterize carob cultivars. The values of morphological traits obtained by cultivar were compared with those from other countries of the Mediterranean basin. Statistically significant differences were found between cultivars for all characters which were examined, what indicates a high genetic diversity. The relationship among these characters was analyzed by principal component analysis (PCA) resulting in the separation of these cultivars classed in four groups (clusters I–IV) and in four ungrouped cultivars. A three dimension of the model was found to be significant and explained 74.5% of the total variation, in which the first component accounting for 34.6% of the total variation is dominated by fruit characters, while the second component is dominated by seed characters. Cultivars plotted on the left-lower quadrant on the space determined by principal components 1 and 2 are characterized by fruits with high seed yield more appropriated for industrial rentability. The correlation analyses established by cultivar provided a specific understanding about the way how fruit and seed characteristics correlate within each cultivar. This approach can be useful for the development of a breeding programme, aiming to increase the seed yield, seed thickness, individual and total seed weight by fruit, characteristics that are determinant to improve the industrial exploitation of carob.  相似文献   

19.
The sensitivity of developmental stages to high temperature was investigated in chili pepper (Capsicum annuum L. var. Shishito). Plants were subjected to heat stress (38/30 °C day/night) immediately after anthesis for 5 or 10 days, or from 10 to 30 days after anthesis (DAA), from 30 DAA until harvest of the seeds, or immediately after anthesis until harvest of the seeds. Control plants were grown at 30/22 °C (day/night). Exposure to high temperature (heat stress) during different periods of development after anthesis adversely affected fruit growth, seed yield, and seed quality in chili pepper. Heat stress for the whole period after anthesis, and from 30 DAA until harvest reduced the growth period of chili fruits by 15 and 10 days, respectively. Heat stress from 10 to 30 DAA reduced fruit width and fruit weight. The early stage of seed development from anthesis until 10 DAA was sensitive to high temperature, which affected fruit length, fruit weight and seed set. Applying high temperatures to plants for 10 DAA increased the proportion of abnormal seeds per fruit. High temperatures from 10 DAA until 30 DAA inhibited carbohydrate accumulation and adversely affected seed germinability and vigor. These results suggest that the stage of development at which chili peppers are exposed to high temperatures is an important factor in fruit and seed growth and in seed quality.  相似文献   

20.
The application of modern biotechnology for conservation of any endangered species requires an efficient in vitro regeneration protocol. In this study a reliable protocol was developed for in vitro seed germination, protocorm multiplication and subsequent plantlet regeneration of Vanda coerulea, an endangered orchid species. Among the four basal media evaluated for asymbiotic seed germination, Phytamax was found to be the best followed by Murashige and Skoog (MS). Phytamax was also found good for protocorm development. For protocorm like body (PLB) regeneration, protocorms were then further cultured on Phytamax media fortified with different phytohormones either individually or in combinations. The frequency of protocorm like body (PLB) regeneration significantly relied on kinds and concentrations of plant growth regulators used. A combination of 1-naphthaleneacetic acid (NAA) (5.36 μM) and 6-benzyle amino purine (BAP) (3.80 μM) was found to be suitable for maximum PLB regeneration. Healthy plantlets were induced from PLBs when cultured on same basal medium supplemented with activated charcoal (AC – 3.0 g/l). Plantlets with well developed leaves and roots were transplanted to pots filled with a mixture of charcoal, brick pieces and sphagnum moss and transferred to the greenhouse. This protocol will enable mass propagation and conservation of this exquisite orchid.  相似文献   

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