Mild winters, early springs: requirements for species and provenances for the next generations

Transcription

1 Mild winters, early springs: requirements for species and provenances for the next generations Tore Skrøppa Norwegian Genetic Resource Centre and NordGen

2 I will present and discuss: - Implications of climate change on the vegetation period - How trees respond; importance of annual growth rhythm - Winter damage - Choice of plant materials

3 The warmer future The length of the growing season (> 5 C)

4 Earlier spring Høgda et al (Cicero1-2003) Satellite photos

5 Changes since 1960 to 1999 assessed on the same clones in 60 European phenological gardens: - 11 days longer growth season - bud flushing 6 days earlier - autumn colours/leaf abscission 5 days later Fruit trees in western and eastern Norway assessed : - Gradually earlier growth start - Greater changes in eastern Norway The pollination occurs earlier and has a longer duration

6 Climatic adaptation phenology

7 Day length - photoperiod Fundamental environmental factor used by plants to control seasons: - Controls the growth cessation for many species - Interacts with temperature for induction of dormancy for some species (ex. Sorbus, Fraxinus, Syringa) - Some species require long day for bud flushing Locale populations are genetically adapted to the natural day length at the origin The photoperiod is not influenced by climate change

8 Temperature - Important for initiation of growth start in spring - A critical factor for growth and yield - Populations are adapted to local temperature conditions and interactions between temperature and photoperiod in the timing of growth processes Temperature conditions will change, and interactions between temperature and photoperiod are broken

9 Large genetic variation in response to climatic factors - Among species - Among provenances within species - Among families and clones within natural populations Spruce seedlings in freezing tests September 20 From 66ºN - 59ºN

10 Differences between species in timing of bud flushing Date for bud flush (Ås) i 1990 og 1991 (Heide 1993) Difference (mild) (normal) (days) Prunus padus Betula pendula Alnus glutinosa Fagus sylvatica

11 Frost damage on provenances and individuals that have an early growth start Photos: Skrøppa / Norwegian forest and landscape institute

12 Norway spruce families with late growth start have less damage and better growth in the field Trær med skader (%) r = Høyde (cm) r = Mai Juni Start av skuddstrekning Mai Juni Start av skuddstrekning

13 Late-flushing families have less lammas growth

14 More lammas growth due to early growth start?

15 Climatic winter damage - High temperatures in winter, followed by frost events, and influences by winds containing salt water - Frost desiccation, a combination of frost and draught, with high temperatures in the air and frozen ground - Early growth start and flowering due to high spring temperatures, followed by frost events

16 Winter damage in Norway spruce > Often a combination of several abiotic factors such as fluctuation temperature, drought, wind > This particular case in Nordland, Norway: Strong salty wind + frost Photo: Skaret / FMLA-Nordland

17 Damage after a warm winter 1988/89 in Eastern Norway - Continental species had damage to the cambium and dying branches - Maritime species were undamaged Håbjørg (2007)

18 Damage by pests and insects - Insect species will increase their distribution towards the north, the development from the young to the adult stage will be faster, with possibilities for two generations - Local fungi species will benefit from a longer and warmer growth season. New species will move north and may establish permanently - Attack on healthy individuals, men also secondary on weakened individuals

19 Ash a threatened tree species? A new fungus, Chalara fraxinea, has invaded the Nordic region and threatens the genetic resources of ash Caused by climate change?

20 Choice of plant materials - Choose species and provenances that can tolerate the critical weather situations - Avoid materials with and early dormancy break and high risk for frost damage, choose materials with a later growth cessation, deeper dormancy and higher basic temperature for growth start - A northern transfer of materials adapted to variable winter temperatures could be beneficial - Local provenances are generally not optimal - Avoid species/provenances transferred from continental areas

21 Local or transferred materials? - Climate change may make locally adapted species and provenances less adapted to the new climatic conditions - National og international (CBD/MCPFE) conventions/strategies are against transfer of species - National Norwegian strategy (2007) says Landbrukssektoren skal arbeide for å bruke nasjonalt frø og plantemateriale i skogbruk, småhagebruk og offentlige anlegg

22 Questions - Can we use present day provenances/ varieties? - Can we move varieties from southern to northern latitudes? - Interactions between temperature and photoperiod? - Should we plant more seedlings per ha and with a larger genetic diversity? - Will species mixtures have a larger stability?

23 Information is needed - Describe the critical environmental conditions at the planting site - Characterise the properties of plant materials and choose the most appropriate ones, with a high phenotypic plasticity Generate new and more adapted varieties - Do breeding in the most important species to produced materials with the desired properties

24 Breeding is necessary - Breeding goals: - climatic adaptation, phenotypic plasticity - longer growth season - resistance - Testing at several localities - International exchange of breeding materials - Nordic cooperation in breeding - Lack of competence, educate breeders

25 Breeding of spruce and pine in Sweden Several synthetic populations Andersson, Nordiske GENressurser 2002, 36-38

26 Choice of plant material in afforestation Norway spruce in Western Norway - Seed production based on parents selected in well-adapted plantations (Harz-provenances) - Late flushing Baltic provenances Use of introduced species -Douglas fir - Sitka and lutz spruce in Northern Norway - Seed production based on tested parents

27 Thank you!