Breaking seed dormancy and germination in Prunus avium

Wild cherry (Prunus avium) is a native fast growing broadleaved tree in Hyrcanean forests producing valuable wood. Prunus seeds have long dormancy and there is variety of methods for breaking dormancy of its seed. This study was conducted in order to overcoming dormancy and germination of Prunus seed. For this purpose, seeds were collected from Aliabad Katool region in forests of Golestsan province, north of Iran. The seeds with mosocarp, without mesocarp and without endocarp were subjected to warm stratification (4 weeks, 20 ˚C) followed by cold stratification (10 weeks, 5 ˚C). Results showed that mesocarp and endocarp had significant effects on overcoming seed dormancy and germination characteristics. Germination percent, germination speed and germination value in seeds stratified without endocarp were greater than those in seeds stratified with mesocarp and without mesocarp. The results revealed that the seeds without endocarp were the most favorable treatment to break dormancy and to improve germination characteristics in Prunus avium seeds

Effect of moisture regulation method on viability of wild cherry seeds and determination of its threshold drought tolerance

Regulation of seed moisture content is one of the important factors in maintaining and increasing seeds durability and quality which is made by different methods. For this reason, the trial was conducted to regulate moisture content and to determine the threshold drought resistance of wild cherry seeds, using the weight method and oven and desiccator. After calculating weight of the seed samples at the specified moisture content levels, the trend of moisture reduction in oven by temperature change and in desiccator by silica gel was investigated. The results showed that there was high correlation between the calculated moisture content by weight method and the actual one. Thus using this method for prospecting the process of desiccation in wild cherry seeds is appropriate. Also during the process of desiccation, the seed's average viability in desiccator was more than that in oven. Due to stability of the wild cherry seed's viability during the process of moisture reduction, particular threshold for drought tolerance was not defined. Therefore, certain critical moisture content for seeds of this species might not be determined

Investigation on effects of temperature, light and storage treatments on germination of three provenances of Ulmus glabra

This study evaluated the effect of temperature, light and storage treatments on seed germination of three provenances of Ulmus glabra at Mazandaran province of Iran. For this reason, after collecting the seeds from three origins and determining their viability and moisture content, the initial seed germination percentage under temperature and light treatments were studied. Temperature treatments including 20, 25 ºC and 30/20 ºC (8 hours at 30 ºC and 16 hours at 20 ºC) and light treatments including eight hours of light and 24 hours of dark. Also, after seed storage for one year in -4ºC, germination behaviors at the light and temperature treatments were investigated. The results of this study showed that temperature had significant effect on primary germination percentage of Ulmus glabra seeds and in the three provenances. The initial seed germination percentage was the highest at 30/20 ºC in the light and the dark treatments. After one year seed storage, its light demand increased and the highest percentage of seed germination was observed at 30/20 ºC and eight hour light period. There was significant difference between the seed origins in terms of seed germination. Seed germination percentage was the highest in Lajim than the two other provenances

Biological flora of the British isles: Ulmus glabra

1. This account presents information on all aspects of the biology of Ulmus glabra Hudson (wych elm) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation. 2. Ulmus glabra is a large forest tree, and often an important canopy tree in ancient and seminatural woodlands. It is primarily native to the north and west of Britainand much of mainland Europe. It is the only elm native to Ireland. It is the most distinct of the British elms in that it rarely suckers and sets abundant viable seed. Although found on limestone screes and cliffs, and hedgerows, it is primarily awoodland tree, especially on moist, basic soils. In many secondary woodlands, it often cooccurs with Acer pseudoplatanus and has ecological needs that are similar to Fraxinus excelsior. 3. Ulmus glabra has clusters of c. 25 hermaphrodite flowers appearing before the leaves on previous year’s growth. Seeds are wind dispersed, falling in April to July, but remain viable for only a few days. Nevertheless, seedling establishment can be abundant. Hybridisation with other northern European elms is common but hybrids are notoriously difficult to identify and therefore probably under recorded. 4. The health and survival of wych elm in Europe has been seriously compromised since the 1970s due to Dutch elm disease caused by the fungus Ophiostoma novo ulmi, transmitted by elm bark beetles (Scolytus spp.). To the south of its Scottish stronghold, many elms are reduced to small trees regrowing from basal sprouts or seeds. These trees tend to be reinfected once trunk diameter exceeds 10 cm. Fortunately for its long term survival, seed production usually begins a number of years before they are reinfected