Cork oak (Quercus suber L.) has a high ecological and social value and supplies raw materials for the cork industry, a relevant contributor to the economies of Mediterranean countries. Understanding the adaptation potential of cork oak populations to cope with different environmental conditions is a key issue of forest management, particularly for selecting the most adapted genetic material for (re)forestation and assuring the long-term sustainability of the cork industry. Intraspecific variation in fitness surrogate traits (survival, height and stem diameter) was investigated in thirty-five cork oak populations sampled from the entire range of the natural distribution of the species. The study was conducted in two provenance field trials, established in Portugal under different edaphoclimatic conditions. Each trial was surveyed at four tree ages (two ages, 11 and 14 years, were sampled simultaneously in both trials). The trial located at a lower altitude, which had higher mean winter and annual temperatures, exhibited higher growth and survival rates. In both trials, significant genetic variation among cork oak populations was observed for the analyzed traits and evaluated ages. Moroccan populations displayed a higher probability of survival and higher growth rates, while local populations exhibited an intermediate performance. Low to moderate correlations were found between the analyzed traits and the environmental variables of seed origin, suggesting that factors other than climate are likely to be relevant for cork oak adaptation. Moderate to high values of population mean-basis broad-sense heritability (H 2 ≥ 0.44) and high genetic correlations between traits (0.88-0.95) were found for growth traits. This information is crucial for the establishment of a breeding program for the species. With this study, we have improved the knowledge regarding how cork oak performs for fitness surrogate traits in different environments.

African citrus psyllid (Trioza erytreae (Del Guercio)) is a vector insect of the bacterium Candidatus Liberibacter africanus, the putative causal agent of Huanglongbing, the most devastating citrus disease in the world. The insect was found on the island of Madeira in 1994 and in mainland Portugal in 2015. Present in the north and center of the country, it is a threat to Algarve, the main citrus-producing region. Trioza erytreae eggs and first instar nymphs are sensitive to the combination of high temperatures and low relative humidity. Daily maximum air temperature and minimum relative humidity data from 18 weather stations were used to calculate the water vapor pressure deficit (vpd) from 2004 to 2018 at various locations. Based on the mean vpd and the number of unfavorable days (vpd < 34.5 and vpd < 56 mbar) of two time periods (February to May and June to September), less favorable zones for T. erytreae were identified. The zones with thermal and water conditions like those observed in the Castelo Branco and Portalegre (Center), Beja (Alentejo), Alte, and Norinha (Algarve) stations showed climatic restrictions to the development of eggs and first instar nymphs of African citrus psyllid. Effective control measures, such as the introduction and mass release of Tamarixia dryi (Waterson), a specific parasitoid, and chemical control are necessary in favorable periods for T. erytreae development, such as in spring and in areas with limited or no climate restrictions.

Due to the lack of a general drought definition, water users and managers have developed and used different indices. Many studies using drought indices have been made so as to detect drought events or just to compare their results and assess their advantages and disadvantages. In Portugal, these studies have been done for common drought indices; however, an integrated evaluation and comparison using recent data is needed. Therefore, this study is intended to give an updated overview of the behaviour of the proposed indices. This study proposes the usage of PDSI, scPDSI, SPI and SPEI. With the exception of the PDSI, all indices have been calculated through R packages. The results for the studied regions in mainland Portugal suggest that the drought situations are, in general, most significant and frequent than the wet periods. From our results, we can conclude that the SPI model is more sensitive to extreme drought events and can detect them earlier. The PDSI, scPDSI and SPEI are more reliable for drought monitorization at medium and long spells, which might represent the environmental interactions more closely to the reality. Also, the scPDSI tends to reduce the importance of short period recovering. It is then advisable that impact and scientifical studies consider all of these indices or at least some of them to have a broader and complete understanding of the drought situations to be studied.

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