Abstract:
Acest studiu a investigat impactul stresului termic asupra viabilităţii germenilor de fag (Fagus sylvatica L.) de diferită provenienţă: Codru (Republica Moldova) şi Băiuţ (România). Seminţele stratificate timp de două luni au fost germinate, iar germenii expuşi la 40°C, 45°C şi 48°C timp de 15 minute. Rezultatele au arătat că rata de supravieţuire a germinilor neexpuşi stresului termic a fost de 75%, însă la 40°C a scăzut la 55%, iar la 48°C la 25%. Germenii cu radicole mai lungi (7 cm) au tolerat mai bine stresul decât cele cu radicole scurte (1 cm). Stresul termic a inhibat creşterea radiculară şi adaptarea, iar o creştere de doar 5°C (de la 40°C la 45°C) a afectat semnificativ viabilitatea plantulelor. Aceste constatări subliniază importanţa selecţiei de genotipuri rezistente la temperaturi ridicate pentru reîmpădurire şi conservarea fagului în contextul schimbărilor climatice.
Description:
This study investigated the impact of thermal stress on the viability of beech (Fagus sylvatica L.) seedlings from different origins: Codru (Republic of Moldova) and Băiuţ (Romania). Seeds stratified for two months were germinated, and the seedlings were exposed to 40°C, 45°C, and 48°C for 15 minutes. The results showed that the survival rate of seedlings not exposed to heat stress was 75%, but it decreased to 55% at 40°C and to 25% at 48°C. Seedlings with longer roots (7 cm) tolerated the stress better than those with shorter roots (1 cm). Heat stress inhibited root growth and adaptation, and a mere 5°C increase (from 40°C to 45°C) significantly affected seedling viability. These findings highlight the importance of selecting genotypes resistant to high temperatures for reforestation and the conservation of European beech in the context of climate change.
