Interspecific Crosses Research Articles

Novel Alleles from Cicer reticulatum L. for Genetic Improvement of Cultivated Chickpeas Identified through Genome Wide Association Analysis.

The availability of wild chickpea (Cicer reticulatum L.) accessions has the potential to be used for the improvement of important traits in cultivated chickpeas. The main objectives of this study were to evaluate the phenotypic and genetic variations of chickpea progeny derived from interspecific crosses between C. arietinum and C. reticulatum, and to establish the association between single nucleotide polymorphism (SNP) markers and a series of important agronomic traits in chickpea. A total of 486 lines derived from interspecific crosses between C. arietinum (CDC Leader) and 20 accessions of C. reticulatum were evaluated at different locations in Saskatchewan, Canada in 2017 and 2018. Significant variations were observed for seed weight per plant, number of seeds per plant, thousand seed weight, and plant biomass. Path coefficient analysis showed significant positive direct effects of the number of seeds per plant, thousand seed weight, and biomass on the total seed weight. Cluster analysis based on the agronomic traits generated six groups that allowed the identification of potential heterotic groups within the interspecific lines for yield improvement and resistance to ascochyta blight disease. Genotyping of the 381 interspecific lines using a modified genotyping by sequencing (tGBS) generated a total of 14,591 SNPs. Neighbour-joining cluster analysis using the SNP data grouped the lines into 20 clusters. The genome wide association analysis identified 51 SNPs that had significant associations with different traits. Several candidate genes associated with early flowering and yield components were identified. The candidate genes and the significant SNP markers associated with different traits have a potential to aid the trait introgression in the breeding program.

Synthetic Tetraploid of Oncidium crispum Lodd. (Orchidaceae).

In ornamental plants, artificial polyploidization has enabled the creation of new cultivars. Due to their high commercial value in the international flower market and their ornamental characteristics, such as the shape, size, color, and durability of their flower, orchids have received great attention in studies of artificial polyploidization. Here we described the protocol used for polyploid induction in Oncidium crispum, an epiphyte species native of southeastern Brazil, of great ornamental interest and widely sold in flower shops. The species stands out for having inflorescence with large flowers, brown in color with yellow spots. In addition, O. crispum has great potential for use in genetic improvement programs since the species is widely used in interspecific crosses. Closed capsules containing mature O. crispum seeds were subjected to running sterilized water for 10min and then to a 1.5% sodium hypochlorite solution for 10min. Small portions of seeds were introduced into 50mL of water-soluble fertilizer with macro- and micronutrients (B&GTM) plus 0.7% agar. Explants originating from seeds previously in vitro germinated were submitted to 0.05% and 0.1% of colchicine for 4days and 8days. Flow cytometry and chromosome counts confirmed that the protocol successfully produced synthetic polyploid plants.

Embryo Rescue Technique in Buckwheat Fagopyrum esculentum Moench.

Culture of immature buckwheat embryos is an excellent explant for tissue culture and regeneration in vitro, as well as a method of embryo rescue in case of fruit abortion especially in interspecific crosses. Here, we describe the method of immature embryo rescue using a differentiated approach to different age groups. The method involves the development of embryos along the path of direct embryogenesis bypassing the callus stage.

Identification of Novel Quantitative Trait Loci Associated with Table Grape Fruit Quality Characteristics in a Segregating Population and Transferability of Existing Quality Markers

Grape (Vitis) production and fruit quality traits such as cluster size, berry shape, and timing of fruit development are key aspects when selecting cultivars for commercial production. Molecular markers for some, but not all, of these traits have been identified using biparental or association mapping populations. Previously identified markers were tested for transferability using a small (24 individual) test panel of commercially available grape cultivars. Markers had little to no ability to differentiate grape phenotypes based on the expected characteristics, except the marker for seedlessness. Using a biparental interspecific cross, 43 quantitative trait loci (QTLs) (previously identified and new genomic regions) associated with berry shape, number, size, cluster weight, cluster length, time to flower, veraison, and full color were detected. Kompetitive allele-specific polymerase chain reaction markers designed on newly identified QTLs were tested for transferability using the same panel. Transferability was low when use types were combined, but they were varied when use types were evaluated separately. A comparison of a 4-Mb region at the end of chromosome 18 revealed structural differences among grape species and use types. Table grape cultivars had the highest similarity in structure for this region (>75%) compared with other grape species and commodity types.

Interspecific crosses of linseed species

Interspecific crosses of linseed species

Development of regenerated plants of interspecific wheat hybrids using immature embryos as explants

Nowadays particular attention in winter wheat breeding is paid to the introduction of biotechnological methods. The culture of immature embryos in vitro is an alternative way to produce hybrids that often do not develop fully in vivo. The purpose of the current study was to estimate the ability of immature embryos of interspecific winter wheat hybrids for callus induction, morphogenesis, and plant regeneration on artificial nutrient media, as well as to select optimal conditions for obtaining full-fledged plants with all the botanical characteristics of the species. The research material included 5 hybrid combinations of interspecific crosses between durum (Triticum durum DESF.) and common (Triticum aestivum L.) winter wheat. The material was collected during one field season (2022). Immature embryos were used as explants. Culture media were according to Murashige-Skoog (MS), and they differed in the content of hormones and organic substances. There has been found that the hybrid combinations were characterized by a variety of morphogenic responses. The manifestation of callusogenesis was not high enough and averaged 22–32 % depending on the nutrient medium. Rhizogenesis averaged from 1–6.7 %, and ended with the formation of roots. The process of formation of embryoid- and hemmorizogenesis was best demonstrated by the hybrid combination No.1, and on two media. All processes of morphogenesis excepting ‘rhizogenesis’ varied greatly among hybrid combinations. The largest number of regenerated plants was obtained from hybrid combination No.1 (61 pcs., 54.5 %). After vernalization and acclimatization, 38 % of the plants survived from the number of planted embryos. The largest number of heads (79 pcs.) was formed according to hybrid combination No.1, on average 1.46 heads per plant. However, not all heads were fertile. The results of the correlation analysis made it possible to identify indicators that closely correlated with the amount of plant regeneration, namely, the high yield of embryoid- and hemmorizogenic structures ensured a high frequency of plant regeneration (r = 0.769).

Phenotypic traits of reciprocal tetraploid hybrids derived from tetraploid Crassostrea gigas and tetraploid Crassostrea angulata

Allotetraploid has the potential to become an important germplasm resource for genetic breeding of organisms. Previously, autotetraploid oysters have played a great role in the worldwide triploid oyster industry by mating with diploids to produce triploid seeds. However, whether allotetraploid oysters can be produced and their performance is unknown. Here, we carried out an artificial interspecific cross between tetraploid Crassostrea gigas and teraploid C. angulata, forming 4 experimental groups, two autotetraploid groups (GGGG: tetraploid C. gigas♀ × C. gigas♂, AAAA: C. angulata♀ × C. anguata♂) and two allotetraploid groups (GGAA: C. gigas♀ × C. anguata♂, AAGG: C. angulata♀ × C. gigas♂). These two pure tetraploid species hybridized without barrier to gamete reproductive isolation, resulting in high fertilization rate (>93%) and acceptable hatching rate (>78%). Reciprocal tetraploid hybrid survival rates were higher than that of pure tetraploids. Some degree of growth heterosis was observed, especially for yearlings. Mid-parent heterosis of wet weight and shell height at day 360 was 31.58% and 16.11%, respectively, which were primarily influenced by egg origin and mating strategy. Overall, the order of performance of the four groups in the warm water area was as following: AAGG>GGAA>AAAA>GGGG. Our results demonstrate that artificial interspecific hybridization between two tetraploid oysters can produce heterosis and that teraploid hybrids have the potential to become new genetic resources for the improvement of polyploid oysters.

Heterosis and combining ability in intraspecific (G. hirsutum L.) and interspecific (G. hirsutum L. × G. barbadense L.) cotton hybrids

The inheritance of most important economic characters, heterosis and combining ability were studied in six interspecific (G. hirsutum L. × G. barbadnese L.) and three intraspecific hybrid combinations. There were found different types of inheritance of productivity, boll weight and lint percentage and fiber length in the individual crosses. The genetic variance for productivity and fiber length was mainly non-additive, while for lint percentage it was additive. Although non-additive genetic variance prevailed for productivity and fiber length, only individual crosses showed positive heterosis, outperforming the better parent. Of the female forms, the cultivar Helius was identified as a very good general combiner for productivity. From the male forms the cultivar Ashkabat emerged as a very good general combiner for productivity, boll weight and lint percentage. The cultivars Mytra (female), Karshinski-2 and C-6037 (male) were determined as very good general combiners for fiber length. All these cultivars, with the exception of C-6037, had low SCA variances, their high GCA was mainly due to additive gene effects, and they were very suitable for synthetic selection. The cross Helius × Ashkabat was found to be most valuable for the selection of productivity because of the highest mean performance and the highest level of heterosis with high SCA effects. All intraspecific hybrids were found to be most promising for improving lint percentage. The interspecific cross combinations Mytra × C-6037, Helius × C-6037 and Mytra × Karshinski-2, having the longest fibers, the first two with high SCA effects were most valuable for fiber length improvement.

Interspecific hybridization in niger (Guizotia abyssinica l.f. cass)

The study presents the results of successful establishment and interspecific hybridization of cultivated Niger (Guizotia abyssinica) with one of its wild allies, G. scabra. Out of four accessions of wild species collected from Kenya, two accessions (P3: EC1077609 and P4: EC1077610) could be successfully established that were used in interspecific crosses. Direct and reciprocal crosses were made (JNS-28 x P3; JNS-28 x P4) and adequate quantity of F1 seed was obtained in crosses of wild x cultivated. Morphological analysis of the F1 hybrids showed the vigorous nature of the interspecific hybrids and the results are presented.

Prebreeding and genetic enhancement of cultivated sunflower (Helianthus annuusL.) using diploid wild Helianthus species in India

Pre-breeding activities using promising diploid wild Helianthus like Helianthus annuus (wild), H. argophyllus, H. praecox, H. debilis and H. petiolaris and popular cultivar (ARM-243B) have been initiated at ICAR Indian Institute of Oilseeds Research, Rajendranagar, Hyderabad to increase the frequency of desirable genes, wider adaptability and a broad genetic base. Wider variability was observed for yield and yield contributing traits besides disease reactions within and between species. Evaluation of a few populations for biotic stresses and yield related traits resulted in the identification of desirable introgression lines. The highest seed yield (42.5 g/plant) was reported in combinations with H. annuus (wild), H. petiolaris (40.2 g/plant) and H. debilis (39.8 g/plant). Interspecificderivatives derived from H. praecox were found resistant to powdery mildew. Interspecific derivatives of H. argophyllus, namely PB-1001, PB-1003, PB-1005, PB-1007, PB-1008, PB-1014, and PB-1019 were resistant to leafhoppers, while PB-1003, PB-1005, and PB-1007 exhibited resistant reactions to downy mildew under sick plot conditions. H. debilis derivatives viz., PB-120, PB-127, PB-128, PB-129 and PB-130 recorded >40% oil content. The pre-breeding lines derived from these interspecific cross combinations serve as an invaluable reservoir of genes for carrying out basic studies on the key traits as well as the exploitation of agronomically desirable traits in the AICRP sunflower breeding programmes.

Investigation of the medium for barley (Hordeum vulgare L.) immature embryo culture

Germination of immature embryos of interspecific crosses in vitro is the most important problem in barley breeding programs. The effect of four media types (MS, ½ MS, B-5, ½ B-5 on immature embryo culture of nine barley varieties (Sameer, Buraq, Aksad, Shuaa, Arevat, Alwarkaa, Alhadher, Amel, and Rihan) was studied by using completely randomized design (C.R.D.) with six replicates. Analysis of variance showed highly significant effects due to varieties, media, and interaction for all studied characteristics, indicated high variation among varieties and media. Aksad variety was significantly superior to all varieties for all studied traits except root number (RN). Medium of ½ B-5 was significantly superior to all media for all studied traits. Aksad interactions with media except B-5 media gave full germination with highly significant superiority over all interactions. Aksad x ½ B-5 interaction showed a highly significant superiority for shoot length (SL) and RL. As a result, ½ B-5 medium was the efficient medium for germination of immature embryos of most varieties. These varieties could be used in breeding program of interspecific crosses with wild species by using ½ B-5 medium.

Genotype by environment model predictive ability in Miscanthus

AbstractMiscanthus is a genus of perennial grasses native to East Asia that shows promise as a biofuel energy source. Breeding efforts for increasing biofuel capability in this genus have focused on two species, namely M. sinensis (Msi) and M. sacchariflorus (Msa). For these efforts to succeed, it is critical that both Msi and Msa, as well as their interspecific crosses, can be grown at a wide range of latitudes. Therefore, the purpose of this study was to investigate how well existing data from Msi and Msa trials grown at locations throughout the northern hemisphere can train state‐of‐the‐art genomic selection (GS) models to predict genomic estimated breeding values (GEBVs) of dry yield for untested Msi and Msa accessions in untested environments. We found that accounting for genotype by environment interaction in the GS model did not notably improve predictive ability. Additionally, we observed that locations at lower latitudes showed higher predictive ability relative to locations at higher latitudes. These results suggest that it is crucial to increase the number of trial locations at higher latitude locations to investigate the source of this correlation. This will make it possible to train GS models using data from environments that are similar to growing conditions at the locations targeted by Msi and Msa breeders. Such an increase of trial locations in target environments could pave the way toward advancing breeding efforts for overwintering ability in Msi and Msa, and ultimately support the potential of Miscanthus as a biofuel crop.

Selection for drought tolerance in backcross populations derived from interspecific crosses of Solanum lycopersicum × Solanum pennellii

AbstractDrought strongly limits tomato yield, and the introgression of genes from wild tomatoes is a powerful tool to obtain drought‐tolerant progenies. The aim of this study was to select drought‐tolerant transgressive progeny obtained from interspecific crosses between drought‐susceptible tomatoes (Solanum lycopersicum) × drought‐tolerant wild species (Solanum pennellii) under in vitro and greenhouse conditions. BC1F2 populations were advanced from backcrosses between F1 × Jumbo AG‐592 (cultivar for fresh consumption) and F1 × BRS Tospodoro (cultivar for industrial processing). For this, BC1F2 seeds were germinated in vitro and evaluated for tolerance to drought. Then, eight genotypes from each BC1F2 were selected and submitted to 14 days of drought (0% of water supply) or well‐watered (100% of water supply) in greenhouse conditions and evaluated for growth, water balance and gas exchanges. Using in vitro assays with mannitol‐induced drought proved to be effective for the initial screening of drought‐tolerant BC1F2 plants, while greenhouse experiments showed that drought decreased photosynthesis in all genotypes, but almost all the BC1F2 progenies had greater photosynthetic capacity, water balance and growth than their commercial parents. As a result, we selected six progenies for fresh consumption and six progenies for industrial processing with increased drought tolerance.

Characterisation and Identification of Vines from Fuerteventura (Canary Volcanic Archipelago (Spain)) Using Simple Sequence Repeat Markers

A prospection was carried out on Fuerteventura Island in order to explore the existing biodiversity of Vitis vinifera ssp. vinifera in almost desert conditions (<120 mm per year). For this purpose, 40 individuals were collected and genotyped with 20 SSRs. Nine known varieties and one unknown variety, named Majorera on the island, were identified. In addition, four new mutations were found in the varieties Listan negro and Listan prieto, respectively. Thirteen unknown individuals and five erratic accessions were identified. Seven new names are proposed for inclusion in the world databank (one main name (Majorera), one new synonym for Listan negro (Hoja moral), four new mutation names (Listan prieto de Antigua, Listan prieto de Vega, Hoja moral de El Rosario and Hoja moral de Betancuria) and a new synonymy for Muscat Hamburg (Moscatel), which is very widespread on the island). Finally, the possibility is raised that the new Majorera variety is not a pure vinifera but the product of an interspecific cross, as has happened with the variety found on the island of La Palma, Bienmesabe tinto. Once again, the Canary Archipelago shows itself to be a possible centre for the creation of biodiversity for the cultivated vine.

Discovery of male sterility from an interspecific cross between Jatropha curcas and J. integerrima

AbstractJatropha (Jatropha curcas L.) is a shrub that produces non-food oil and can potentially be used for biodiesel production. An interspecific cross was made between J. curcas and peregrina (J. integerrima) to increase genetic diversity. Interestingly, male sterility was observed in the F2 population. Out of the 445 F2 plants, five, namely, ms-1 to ms-5, exhibited male sterility, characterized by unopened and distorted stamens without pollen. The parental jatropha, peregrina, F1 and F2 had fertile pollen grain rates of 90.61%, 96.39%, 81.46% and 75.39%, respectively. To verify the fertility of the pistils in the male sterile plants, they were pollinated through selfing, opening and hand crossing with fertile pollen. All of the ms lines experienced seed abortion with or without fruit, except for ‘ms-5’, which produced seed.

Diversity of Fruit Flies on Three Varieties of Mango in Kuningan Regency, West Java, Indonesia

Fruit flies (Bactrocera spp.) are the major pests on mangoes that constrain the efforts to increase the production and quality of mangoes, causing yield losses of up to 100%. Kuningan Regency is one of the largest mango-producing areas in West Java. However, there is no study about the species of fruit fly in the mango plantation at Kuningan Regency, West Java. This study aimed to fruit fly inventory on Gedong Gincu, Arumanis, and Cengkir mangoes. The research used a survey method and was analyzed using descriptive analysis. Purposive sampling was used to determine mango samples by randomly selecting fruits that were attacked by fruit flies from mango fields owned by farmers, wholesalers, and markets in Sukadana Village, Ciawigebang District, Kuningan Regency, West Java. The samples were taken to the Plant Pest Laboratory at Universitas Padjadjaran for incubation till the appearance of imago. The findings showed that the Bactrocera dorsalis complex consisted of B. dorsalis, B. carambolae, and interspecific crosses. The fruit fly diversity index was considerably low (0.21<H‘<0.53). B. dorsalis was determined to be the predominant species in all mango variety and locations, with a value of 95.12%.

Resistance of 10 Genotypes of Grapevines to Downy Mildew Disease (Plasmopara viticola Berk. et Curt.) on Batu High Land

Downy mildew (Plasmopara viticola Berk. et Curt.) is a major disease of grapevines (Vitis spp.) in Indonesia, especially during the rainy season. The use of downy mildew-resistant grape varieties is an effective solution to increase yields, but it is not always easy because grapes are plants that come from subtropical regions that are adaptive to growing in the lowlands of Indonesia. This study was aimed to test the resistance of 10 grape genotypes and species to downy mildew. Field trials in the Batu highlands of East Java used the natural inoculation method against 10 genotypes of productive grapevines with 1 resistant and 1 susceptible control genotypes using a randomized block design with 3 replications. The results showed that the P. viticola fungus found at the study site had the best performance on all resistance characters such as latency, number of spore spots, number of non-spore spots, resistance score, and intensity of disease attack on jestro AG5, Jestro AG45, Jestro AG86. Jestro AG5 is the most resistant genotype based on disease severity index. Vitis labrusca was the most disease resistant species, Vitis vinifera was the most sensitive, and Vitis interspecific crosses had moderate resistance. The resistant genotypes Jestro AG 45 (V. interspecific cross) and Jestro AG 86 (V.vinifera) need to be investigated further for their resistance mechanisms and their potential as parents in breeding programs.

РЕЗУЛЬТАТЫ СЕЛЕКЦИОННОЙ РАБОТЫ ПО СОЗДАНИЮ БЕССЕМЯННЫХ СОРТОВ ВИНОГРАДА ВО ВНИИВиВ ИМЕНИ Я.И. ПОТАПЕНКО

In the grape assortment of the industrial viticul-ture zone of Russia, there are few seedless varie-ties suitable for growing in an uncovered crop and obtaining marketable fresh and dried grapes, high-quality wine. Biologically and technologi-cally plastic seedless grape varieties that produce high-quality products are in great demand by production and consumers. The article discusses the agrobiological characteristics of seedless grape varieties bred in All-Russian Research Ya.I. Potapenko Institute for Viticulture and Winemaking, obtained as a result of interspecific crosses: Zolotse, Kivin, Cocktail, Pamyati Smir-nova, Shayan, Elf and Yarushka. Among these varieties according to the results of the study, the most winter-hardy ones were identified − Yarushka and Elf. Varieties of Pamyati Smirno-va, Cocktail, Zolotse are identified as sources of resistance to fungal diseases. High rates of seed-lessness (II and III categories) had the varieties: Kivin, Yarushka and Cocktail. The conducted studies allow us to recommend varieties for fresh consumption: Zolotse, Kivin, Pamyati Smirnova, Yarushka; for production of dried products: Zolotse, Kivin, Cocktail, Elf and Yarushka; for wine production all except of Pamyati Smirno-va. They all are recommended for cultivation in the 6th region (North Caucasus) without winter covering.

Genetic relatedness among interspecific hybrids in the genus Capsicum and their implications in breeding King chilli

The present study explores the potentiality of interspecific crosses using three different Capsicum species, comprising of two C. annuum (Krishna and Capsicum), five C. chinense (King chilli A1, A5, A18, A19, A20) and one C. frutescens (Mem) genotypes, with the objective to identify the incompatibility barriers, accomplish the morpho-molecular characterization of parents and hybrids and assess the genetic relatedness between the genotypes.Amongst the three species used for the crossing programme, 'Krishna' (C. annuum) and 'Mem' (C. frutescens) are local cultivars of Assam (India) and possess excellent adaptability. Guinness World Records certified King chilli, or 'Bhut Jolokia' (C. chinense), as the world's hottest chilli (10,001,304 SHU) in September 2007. King chilli has tremendous export potential but is prone to viral diseases, thereby necessitating the transfer of desirable disease resistance from local cultivars.It was observed from the study that the reciprocal crosses involving C. chinense and C. frutescens were compatible, but C. frutescens (Mem) was crossable with only accession A5, suggesting genotype specificity in the interspecific crosses. The usual Euclidean distance between Mem and A5 was 716.605Similarly reciprocal crosses involving C. annuum and C. chinense were partially incompatible. Both the C. annuum (Krishna, Capsicum) genotypes successfully crossed with King chilli accession A18 thereby exhibiting genotype specificity. It was observed that in the cross A18 x Krishna the F1 seeds failed to germinate and in the cross A18 x Capsicum the F1 plants exhibited dwarfism. Hence, unilateral incompatibility was observed when King chilli accession A18 was used as the female parent. In the reciprocal crosses, germination and plant development was normal.The pollen viability ranged from 72.64 to 94.92 % for parents and 23.55 to 81.02 % for the hybrids. Thus, hybrids exhibited lower pollen viability compared to their parents. Significant morphological differences were visible between the parents and their combinations; some features were similar to the male or female parent, and others were either intermediate or novel.Parental polymorphism was detected using thirty random SSR primers, and the markers showing polymorphic bands were used to confirm the hybridity of F1s. Therefore, an attempt was made in this study to assess the possibility of interspecific crosses to transfer disease resistance from the related species to enhance the quality of King chilli, thus improving its commercial valve.

RAIZ’s eucalypt genetic improvement program: The path taken and new challenges

RAIZ is a forest and paper research institute, part of The Navigator Company, a Portuguese pulp and paper company. Its eucalypt genetic improvement program started in the mid-1980s, focused mainly on E. globulus, which is well suited to the local soil and climate conditions and has outstanding wood qualities for pulp and paper production. Initially, main selection criteria were growth, survival to drought conditions, wood density and pulp yield. Cloning was the main form to transfer results into operational plantations and, as a result, rooting ability was also a key trait for successful large-scale nursery plant production. These requirements were maintained for several decades during which the program has achieved substantial gains and the E. globulus clonal forest was a reality. Meanwhile, interspecific hybridization has been tested mainly to achieve higher drought and pest resistance. As a result, the clonal program includes several hybrids. Currently, 11 clones, including three hybrids, are in nursery large-scale production, with operational gains of 30-50% over unimproved stocks, in terms of pulp produced per hectare. In the last decade, more than 250 controlled-crosses were carried out, including 70 interspecific crosses. More than 400 new clones, including 50 hybrids, and approximately 400 seed lots, including 100 hybrids and other species lots, have been tested across over 140 sites. Advanced BLUP analysis techniques are used since mid-1990’s to support strategic planning decisions, including more than 125,000 records for survival, 85,000 records for height and diameter, 57,000 pilodyn and 6,000 NIR records, collected from 219 trials, and covering about 45,000 individual genotypes. Nevertheless, efforts to face climate changes must be intensified, especially to mitigate the effects of drought and pests that currently affect a substantial portion of the forest estate. In the last 3 years, more than 100 new genotypes were selected from hybrids progeny trials involving species such as E. grandis, E. viminalis, E. saligna, E. rudis, E. urophylla, and E. tereticornis. Their multiplication and testing are undergoing, and results are expected within 5 years. In addition, an expanded approach to further diversify and strengthen of eucalypt genetic pool is being implemented, introducing species like E. cladocalyx, E. gomphocephala, E. benthamii, E. melliodora, E. punctata, or E. dunnii, aiming to enhance resilience to environmental challenges and ensuring the sustainability of Portugal's eucalyptus forests.