Variation in timing of bud-burst of Ulmus minor clones from different geographical origins

2006 ◽  
Vol 36 (8) ◽  
pp. 1982-1991 ◽  
Author(s):  
Luisa Ghelardini ◽  
Mauro Falusi ◽  
Alberto Santini
Keyword(s):  
Thermal Time ◽  
Ex Situ ◽  
Bud Burst ◽  
Dormancy Release ◽  
Natural Area ◽  
Ulmus Minor ◽  
Northern Latitudes ◽  
Ex Situ Collections ◽  
Time Requirements ◽  
Vegetative Bud

The vegetative bud-burst phenology of field elm (Ulmus minor Mill.) clones originating from a large geographical range within the species natural area was studied at three European sites over a 5-year period in ex situ collections constituted for the conservation of elm genetic resources. At all the sites and in all the years of study, the date of bud burst and the required thermal time to bud burst were directly related to latitude and altitude of origin of the clones. Nevertheless, the differences among origins were reduced with increasing the chilling duration, suggesting that the clones from more northern latitudes and higher altitudes required longer chilling for dormancy release. Analyses of variance performed on selected groups of clones from different latitudinal origins showed that the order of bud burst was stable among years and that the thermal time requirements decreased in all the groups with increasing chilling, with significant differences among groups; southern clones satisfied their chilling requirements after a shorter chilling duration.

Effects of thermal model and base temperature on estimates of thermal time to bud break in white spruce seedlings

2010 ◽  
Vol 40 (9) ◽  
pp. 1815-1820 ◽  
Author(s):  
Rongzhou Man ◽  
Pengxin Lu
Keyword(s):  
White Spruce ◽  
Climatic Conditions ◽  
Thermal Time ◽  
Growing Degree Days ◽  
Base Temperature ◽  
Bud Break ◽  
Bud Burst ◽  
Degree Days ◽  
Growing Degree Hours ◽  
Time Requirements

To improve the predictability of bud burst and growth of boreal trees under varying climate, the thermal time for bud break in white spruce ( Picea glauca (Moench) Voss) seedlings was evaluated under a range of temperature conditions in controlled environment chambers. Thermal time requirements were calculated as the sum of growing degree days or growing degree hours above base temperatures ranging from –1 to 5 °C. The results indicated that the common modeling approach, which uses a high base temperature of 5 °C and growing degree days, may not be appropriate for future climatic conditions. Estimates of thermal time requirements using a base temperature of 5 °C varied considerably among temperature treatments and thus would reduce the predictability of bud burst under changing climate. In contrast, estimates of thermal time requirements with lower temperatures closer to 1 °C were relatively consistent among treatments. Growing degree hour models were less sensitive to base temperature than degree day models. These results should help in the selection of appropriate base temperatures and thermal time models in quantification of thermal time for bud burst modeling in other boreal trees.

scholarly journals Gap analyses of priority wild relatives of food crop in current ex situ and in situ conservation in Indonesia

2021 ◽  
Author(s):  
Wiguna Rahman ◽  
Joana Magos Brehm ◽  
Nigel Maxted ◽  
Jade Phillips ◽  
Aremi R. Contreras-Toledo ◽  
...  
Keyword(s):  
Protected Areas ◽  
Protected Area ◽  
In Situ Conservation ◽  
Wild Relatives ◽  
Ex Situ ◽  
Area Network ◽  
Complementarity Analysis ◽  
Ex Situ Collections ◽  
Conservation Actions

AbstractConservation programmes are always limited by available resources. Careful planning is therefore required to increase the efficiency of conservation and gap analysis can be used for this purpose. This method was used to assess the representativeness of current ex situ and in situ conservation actions of 234 priority crop wild relatives (CWR) in Indonesia. This analysis also included species distribution modelling, the creation of an ecogeographical land characterization map, and a complementarity analysis to identify priorities area for in situ conservation and for further collecting of ex situ conservation programmes. The results show that both current ex situ and in situ conservation actions are insufficient. Sixty-six percent of priority CWRs have no recorded ex situ collections. Eighty CWRs with ex situ collections are still under-represented in the national genebanks and 65 CWRs have no presence records within the existing protected area network although 60 are predicted to exist in several protected areas according to their potential distribution models. The complementarity analysis shows that a minimum of 61 complementary grid areas (complementary based on grid cells) are required to conserve all priority taxa and 40 complementary protected areas (complementary based on existing protected areas) are required to conserve those with known populations within the existing in situ protected area network. The top ten of complementary protected areas are proposed as the initial areas for the development of CWR genetic reserves network in Indonesia. It is recommended to enhanced coordination between ex situ and in situ conservation stakeholders for sustaining the long term conservation of CWR in Indonesia. Implementation of the research recommendations will provide for the first time an effective conservation planning of Indonesia’s CWR diversity and will significantly enhance the country’s food and nutritional security.

scholarly journals Do living ex situ collections capture the genetic variation of wild populations? A molecular analysis of two relict tree species, Zelkova abelica and Zelkova carpinifolia

2014 ◽  
Vol 23 (12) ◽  
pp. 2945-2959 ◽  
Author(s):  
Camille Christe ◽  
Gregor Kozlowski ◽  
David Frey ◽  
Laurence Fazan ◽  
Sébastien Bétrisey ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Molecular Analysis ◽  
Tree Species ◽  
Ex Situ ◽  
Wild Populations ◽  
Ex Situ Collections

Gibberellin A4/7 enhances seed-cone production in field-grown black spruce

1988 ◽  
Vol 18 (1) ◽  
pp. 139-142 ◽  
Author(s):  
Rong H. Ho
Keyword(s):  
Vitamin E ◽  
Black Spruce ◽  
Seed Orchard ◽  
Shoot Elongation ◽  
Bud Burst ◽  
Lateral Shoot ◽  
Cone Production ◽  
Seed Cone ◽  
Vegetative Bud ◽  
Needle Primordia

Black spruce (Piceamariana (Mill.) B.S.P.) grafts growing in a seed orchard were sprayed with gibberellin A4/7, and grafts and trees in families growing in arboreta were sprayed with gibberellin A4/7 and (or) vitamin E from vegetative bud burst to the end of shoot elongation. Gibberellin A4/7 was very effective in promoting seed cones and 400 mg/L appeared optimal. Vitamin E at 1000 mg/L was not effective. Vegetative bud burst occurred in mid-May and shoot elongation ended in late June. Needle primordia were visible on the apices of newly formed buds at the end of June. Reproductive buds had fewer bud scales than vegetative buds. It appeared that potential reproductive buds terminated their bud scale initiation earlier. Gibberellin A4/7 application to promote seed-cone production should be carried out before bud-type differentiation. This coincides with the end of lateral shoot elongation.

scholarly journals Ex situ conservation of genetic resources of field elm (Ulmus minor Mill) and European white elm (Ulmus laevis Pall)

Genetika ◽  
2004 ◽  
Vol 36 (3) ◽  
pp. 221-227
Author(s):  
Jelena Aleksic ◽  
Sasa Orlovic
Keyword(s):  
Genetic Resources ◽  
Ex Situ Conservation ◽  
Ex Situ ◽  
In Vitro Production ◽  
Ulmus Minor ◽  
Conservation Of Genetic Resources ◽  
Ulmus Laevis ◽  
Vitro Production

Principles of the conservation of genetic resources of elms (Ulmus spp) do not differ fundamentally from the general principles accepted for the conservation of genetic resources of other common Noble Hardwoods. Efficient conservation can best be achieved through appropriate combination of in situ and ex situ methods, which have distinct advantages. Besides that, ex situ conservation is employed when emergency measures are needed for rare endangered populations and when populations are too small to be managed in situ (e.g. risks of genetic drift and inbreeding). The aim of our research is ex situ conservation of genetic resources of field elm {Ulmus minor Mill) and European white elm (Ulmus laevis Pall) through establishment of field genebanks. Sampling was conducted in one population of field elm and one population of white elm. Plant material (buds) from 8 trees of field elm and 10 trees of white elm was used for in vitro production of clones. Obtained clones will be used for establishment of field genebanks on the experimental estate of the Institute of Lowland Forestry and Environment.

Ex situ collections of plants and how they adjust to ABS conditions *

2015 ◽  
pp. 207-225 ◽  
Author(s):  
Susette Biber-Klemm ◽  
Kate Davis ◽  
Laurent Gautier ◽  
Michael Kiehn ◽  
Sylvia I. Martinez
Keyword(s):  
Ex Situ ◽  
Ex Situ Collections

Key issues facing genebanks in preserving crop genetic diversity ex situ: overview of the range of challenges

2021 ◽  
pp. 139-154
Author(s):  
Paula Bramel ◽  
Keyword(s):  
Genetic Diversity ◽  
Genetic Resources ◽  
Plant Genetic Resources ◽  
Cost Effective ◽  
Ex Situ ◽  
Crop Genetic Diversity ◽  
Ex Situ Collections ◽  
Key Issues ◽  
Market Preference ◽  
The Impact

This chapter reviews the key issues and challenges facing genebanks in preserving crop genetic diversity ex situ. Local crop genetic diversity is challenged with changes in land use, urbanization, land degradation, changes in agricultural practises, availability of improved varieties, changes in market preference, and the impact of climate change. Efforts have been made to secure plant genetic resources ex situ for future use but there are significant issues related to cost effective, efficient, secure, rational, and sustainable long-term ex situ conservation. It begins by addressing issues for the composition of ex situ collections and moves on to discuss issues for routine operations for conservation. The chapter also highlights issues for the use of conserved genetic resources, before concluding with a summary of why the development of sustainable genebank systems is so important.

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