Seed storage behaviour and germination characteristics of trees and shrubs of Hong Kong

1999 ◽  
Author(s):  
Wing-yee, Vicky Lam
2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Maria João Pereira ◽  
Helena Fagundo ◽  
Tiago Menezes ◽  
João Couto

This work investigates the potential propagation by seed and cuttings of the Azorean nativeCalluna vulgaris(L.) Hull. for landscape conservation. With that purpose we have performed several germination and cuttings trials, using plant material from wild populations of this species. In the germination trials, we tested the effects of photoperiod length (8 and 16 h), temperature (10, 15, 20, and 20–10°C), seed age (6, 108, and 270 days), temperature of seed storage (4°C and room temperature), and seed surface sterilization on the germination characteristics. In the cuttings trials, we tested the effects of stem cutting type, cultural conditions, cuttings’ harvest month, and rooting substrates on the rooting percentages. The best percentages of germination, 93 and 90%, were obtained with fresh seeds and surface sterilized and sown under an 8 h photoperiod and with temperatures of 10°C or 15°C, respectively; germination after seed storage during 270 days is significantly superior (71%) when seeds are stored at 4°C. The best percentages of rooting were achieved for straight (96%) or heel cuttings (90%) harvested in March, planted on soil from natural stands ofC. vulgarisandErica azoricaHochst., outdoors in half shade, and partially covered with transparent polyethylene film.


Author(s):  
C. Booth

Abstract A description is provided for Nectria cinnabarina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Many species including Ribes and Robinia. This species occurs on conifers and on a wide range of broad-leaved trees and shrubs. DISEASE: Coral spot fungus. Evidence supports the view that this species is a facultative parasite of considerable importance on blackcurrants (48, 3063); it occurs as the cause of cankers of Robinia (54, 1020) and may attack many other woody plants (55, 655). GEOGRAPHICAL DISTRIBUTION: It is very common and widespread in Northern Europe and has frequently been reported from temperate parts of the world, USA, Canada, Australia and New Zealand, and also from India and Hong Kong. TRANSMISSION: Because of the slimy nature of the conidia and the fact that they form a hard crust in dry weather, wind is not considered as important as water in their dispersal. Even the ascospores appear to be extruded or discharged only in moist weather (Jorgensen, 1952). Entry is usually through wounds or dead buds (47, 1181; 48, 3063).


Horticulturae ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 42
Author(s):  
Ai-Hua Wang ◽  
Xiao-Ling Yu ◽  
Yan-Yan Liu ◽  
Shu-Gang Chen ◽  
Fa-Guo Wang

Manglietia crassipes, a critically endangered species narrowly distributed on Mount Dayao in Guangxi, China, is also a species of ornamental interest whose variability has not been explored. Key factors leading to its endangerment have also not been studied. Here, two experiments were conducted to test the effects of different plant growth regulators and different storage conditions on germination characteristics of M. crassipes seeds. Fruit morphology was measured, and germination characteristics of fresh mature seeds were tested in order to assess natural seed vigor. Seeds were soaked in distilled water (control), or gibberellic acid (GA3), 6-benzylaminopurine (6-BA) or indoleacetic acid (IAA) solutions of different concentrations, for 48 h to determine their effects on seed germination. In addition, the effects of different seed storage conditions (constant 4 °C, −7 °C, −20 °C, or 25 °C for 100 days, wet stratification at 4 °C for 100 days) on seed germination were investigated. Results showed that the abortive rate of the mature fruits was high (28.9%) and fresh natural seeds had a low germination rate (G) and germination index (GI). Seed germination was inhibited with 6-BA at all concentrations, but only at less than 100 m·L−1 IAA; otherwise, IAA slightly promoted seed germination. GA3 broke seed dormancy and significantly accelerated seed germination by improving G, GI and initial germination time (IGT), especially over 2500 mg·L−1. The viability of seeds declined no matter how they were stored. However, 4 °C wet stratification storage was preferable for seed vigor and germination power. Our results suggest that the high abortive rate of fruits, low germination of the natural seed, seed dormancy and its intolerance to storage, contributed to the endangerment of M. crassipes. GA3 can break M. crassipes seed dormancy, which can be a benefit for future ornamental breeding and further protection or conservation.


2020 ◽  
Vol 28 (3) ◽  
pp. 139-146
Author(s):  
Hyuck Hwan Kwon ◽  
◽  
Min Gil ◽  
Young Hyun Kwon ◽  
Hyuk Joon Kwon ◽  
...  

Oecologia ◽  
2021 ◽  
Author(s):  
Rosemary J. Newton ◽  
Berin D. E. Mackenzie ◽  
Byron B. Lamont ◽  
Pablo Gomez-Barreiro ◽  
Richard M. Cowling ◽  
...  

AbstractA mechanistic understanding of fire-driven seedling recruitment is essential for effective conservation management of fire-prone vegetation, such as South African fynbos, especially with rare and threatened taxa. The genus Leucadendron (Proteaceae) is an ideal candidate for comparative germination studies, comprising 85 species with a mixture of contrasting life-history traits (killed by fire vs able to resprout; serotinous vs geosporous) and seed morphologies (nutlets vs winged achenes). Individual and combined effects of heat and smoke on seed germination of 40 species were quantified in the laboratory, and Bayesian inference applied to distinguish biologically meaningful treatment effects from non-zero, but biologically trivial, effects. Three germination syndromes were identified based on whether germination was dependent on, enhanced by, or independent of direct fire cues (heat and smoke). Seed storage location was the most reliable predictor of germination syndromes, with soil-stored seeds c. 80% more likely to respond to direct fire cues (primarily smoke) than canopy-stored seeds. Notable exceptions were L. linifolium, with an absolute requirement for smoke to germinate (the third serotinous species so reported), and two other serotinous species with smoke-enhanced germination. Nutlet-bearing species, whether serotinous or geosporous, were c. 70% more likely to respond to fire cues than winged seeds, but there was no evidence for an effect of phylogeny or persistence strategy on germination. This comprehensive account of seed germination characteristics and identification of germination syndromes and their predictors, supports propagation, conservation and restoration initiatives in this iconic fynbos genus and other fire-prone shrubs with canopy or soil-stored seeds.


2015 ◽  
Vol 48 (2) ◽  
pp. 61-67 ◽  
Author(s):  
S A. Tabatabaei

Abstract Seed aging is the main problem of seed storage. Changes of enzyme activity and reduction of seedling growth are consequence of seed deterioration. An experiment was conducted to evaluate the effects of accelerated aging on germination indexes and enzyme activity of barley seeds. Seeds were incubated in closed plastic boxes for the accelerated aging treatments at 41°C. Three accelerate aging regimes were performed by placing seeds at 41°C and relative humidity (RH) of 90-100 % for 0, 4 and 8 day periods. Our results showed that increasing aging duration resulted higher reduction in germination percentage, germination index, mean time to germination, normal seedling percentage, catalase and ascorbate peroxidase. The highest germination percentage, germination index, normal seedling percentage and enzyme activity were achieved in control conditions (0 day of aging). Under aging conditions, germination percentage, means time to germination, germination index, normal seedling percentage and enzyme activity decrease significantly. Also, our results indicated that seed aging is related to decrease of enzymes and may contribute to low germination efficiency. The general decreases in enzyme activity in the seed lowers the respiratory capacity, which in turn lowers both the energy (ATP) and assimilates supply of the germinating seed, also decrease in antioxidant enzymes is linked to an increased accelerated ageing and decreased germination characteristics. Subsequently, proposed a positive relationship between antioxidant enzyme capacity and the vigour of the seed


1998 ◽  
Vol 13 (11-s4) ◽  
pp. S289-S293 ◽  
Author(s):  
SSY WONG ◽  
WC YAM ◽  
PHM LEUNG ◽  
PCY WOO ◽  
KY YUEN

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