Population genetic analyses of Phytophthora cinnamomi reveals three lineages and movement between natural vegetation and avocado orchards in South Africa

Phytophthora cinnamomi is the causal agent of root rot, canker and dieback of thousands of plant species around the globe. This oomycete not only causes severe economic losses to forestry and agricultural industries, but also threatens the health of various plants in natural ecosystems. In this study, 380 isolates of P. cinnamomi from four avocado production areas and two regions of natural vegetation in South Africa were investigated using 15 microsatellite markers. These populations were found to have a low level of genetic diversity and consisted of isolates from three lineages. Shared genotypes were detected between isolates from avocado orchards and natural vegetation, indicating the movement of isolates between these areas. The population from the Western Cape natural vegetation had the highest genotypic diversity and unique alleles, indicating this could be the point of introduction of P. cinnamomi to South Africa. Index of association analysis suggested that five out of six populations were under linkage disequilibrium suggesting a clonal mode of reproduction whereas genotypes sampled from a recently established avocado orchard in the Western Cape were derived from a randomly recombined population. This study provided novel insights on the genetic diversity and spread of P. cinnamomi in South Africa. It also reported on the predominance of triploidy in natural occurring populations and provided evidence for recombination of P. cinnamomi for the first time. The presence of two dominant genotypes in all avocado production areas in South Africa highlight the importance of considering them in disease management and resistance breeding programmes.

Sebaran Dan Nilai Indeks Jasa Ekosistem Pengaturan Kualitas Udara, Iklim Dan Air Di Kabupaten Konawe

Ecosystem services to regulate air quality, climate, water system and water purification are important ecosystem services for human life and other living things. The objective of the research was to analyze the distribution and value of ecosystem services index of air quality, climate, water system and water purification of Konawe Regency. This research was conducted through the study of ecoregion characteristics, covering landforms, natural vegetation types and land cover. Data analysis includes the calculation of ecosystem services index and spatial distribution of ecosystem services index. The results showed that the dominant type of landform in Konawe Regency was the structural hills of metamorphic rock material with natural vegetation in the form of forests and the dominant land cover was primary dry land forests.The average value of the Ecosystem Services Index (ESI) of air quality regulation were 2.88 (medium), climate regulation and water system arrangements were 3.18 (medium) and 3.12 (medium) and water purification settings was 2.12 (low). The average value of the ecosystem services index of the four types of regulatory services was 2.83 with a moderate category. The average ESI value of Sub District of Latoma, Asinua, Routa, Abuki and Meluhu were 3.92, 3.65, 3.62, 3.51 and 3.49 with high categories, respectively. The performance of environmental services of air quality regulation is dominated by a high category of 221,489.56 hectares or 41.99 percent, while climate regulation was dominated by a very high category of 243,516.50 hectares or 46.17 percent. The performance of ecosystem services of water system and water purification arrangements reached an area of 235,459.44 hectares or 44.64 percent and 32,723.16 hectares or 43.04 percent respectively.Keywords: ecoregion, ecosystem services index, regulating ecosystem services,spatial distributionJasa ekosistem pengaturan kualitas udara, iklim, tata air dan pemurnian air merupakan jasa ekosistem penting terhadap kehidupan manusia dan mahluk hidup lain. Penelitian ini bertujuan untuk menganalisis sebaran dan nilai indeks jasa ekosistem pengaturan kualitas udara, iklim, tata air dan pemurnian air Kabupaten Konawe. Penelitian ini dilakukan melalui kajian karakteristik ekoregion, mencakup bentang lahan, tipe vegetasi alami dan tutupan lahan. Analisis data meliputi perhitunganindeksjasaekosistem dan sebaranspasialindeksjasaekosistem. Hasil penelitian menunjukkan bahwa tipe bentang lahan yang dominan di Kabupaten Konawe adalah perbukitan structural lipatan bermaterial batuan metamorfik dengan vegetasi alami berupa hutanpamah (non dipterokarpa) dan tutupan lahan dominan adalah hutan lahan kering primer. Rata-rata nilai Indeks Jasa Ekosistem pengaturan kualitas udara adalah 2,88 (sedang), pengaturan iklim dan pengaturan tata air masing-masing sebesar 3,18 (sedang) dan 3,12 (sedang) dan pengaturan pemurnian air adalah 2,12 (rendah). Nilai rata-rata indeks jasa ekosistem dari empat jenis jasa pengaturan tersebut adalah 2,83 dengan kategori sedang. Nilai IJE rata-rata Kecamatan Latoma yakni 3,92, Kecamatan Asinua sebesar 3,65, KecamatanRouta sebesar 3,62, serta KecamatanAbuki dan KecamatanMeluhu masing-masing 3,51 dan 3,49 dengan kategori tinggi. Kinerja jasa lingkungan pengaturan kualitas udara didominasi oleh kategori tinggi seluas 221.489,56 hektaratau 41,99%, sementara itu pengaturan iklim didominasi oleh kategori sangat tinggiseluas 243.516,50 hektaratau 46,17%. Kinerja jasa ekosistem pengaturan tata air dan pengaturan pemurnian air mencapai luas masing-masing 235.459,44 hektaratau 44,64% dan 32.723,16 hektaratau 43,04%.Kata Kunci:ekoregion, jasa ekosistem pengaturan, indeks jasa ekosistem, sebaran spasial

ОЦЕНКА УРОВНЯ ОЗЕЛЕНЕНИЯ ГОРОДА БИРОБИДЖАНА С ПРИМЕНЕНИЕМ МУЛЬТИСПЕКТРАЛЬНЫХ ДАННЫХ

The urban greenness distribution between functional areas of a medium-size city Birobidzhan was assessed. To this end, normalized difference vegetation index (NDVI) values were calculated based on Sentinel 2 multispectral imaging. Birobidzhan is characterized by a large scatter of NDVI values (from –0.5 to +1). Areas with high levels of greenery are prevalent. They are found in different types of functional zones, but are specific mainly to natural recreational, agricultural, and individual build-up zones as well as to special areas. The spatial distribution of green infrastructure is highly contrast. The downtown part as well as the industrial and storage zones feature a combination of built-up areas with dense woody vegetation, which is often represented by fragments of preserved natural vegetation. In addition, a feature of the contrast is that low level of tree greenness is characteristic for the built-up districts of the city. Thus, in the city of Birobidzhan, ecological functions are largely performed by the natural vegetation present in the natural recreational zones on 70% of the city's area.

Species ethnobotanical values rather than regional species pool determine plant diversity in agroforestry systems

The conversion of natural systems into farms and agroecosystems is the main cause of biodiversity loss. In human-dominated landscapes, understanding the interactions between agroforestry systems and adjacent natural vegetation is fundamental to developing sustainable agricultural systems. Species can move between these two systems with natural systems providing the regional pool of species that shape the agricultural values and conservation value of the agroforestry systems. We investigated the influence of neighboring natural habitats on traditional agroforestry systems in the buffer zone of Pendjari Biosphere Reserve in Benin to understand the contribution of regional processes on the quality of agroforestry systems. We expected that agroforestry parklands adjacent to natural vegetation with high species diversity will also have higher plant species diversity. We found no similarity in plant species composition between agroforestry systems and adjacent natural habitats. A small proportion of species in adjacent natural habitats were found in agroforestry systems. The proportion of shared species was not significantly influenced by plant diversity in adjacent natural habitats or the distance from the agroforestry systems to the natural adjacent habitat. However, plant diversity in agroforestry systems was strongly associated with site ethnobotanical values indicating that farmers act as a supplemental but severe environmental filter of the regional species pool. Our study suggests that promoting the plantation of plants with high ethnobotanical use-value is a potentially viable strategy for sustainable agriculture and ecological restoration in Biosphere reserves.

Non-Native Herbivores Promote Plant Invasions Away From Mountain Roads in the Andes

While the role of environmental filters, usually described by elevation as proxy, and anthropogenic disturbance as drivers of non-native plant diversity and abundance in mountains have been extensively studied, the impact of herbivores are less explored. Livestock grazing can facilitate the introduction of non-native species by seed dispersal and reduce biotic resistance due to consumption and trampling of native plants, even in the highest protected areas in the Andes. We here explored the effects of elevation, livestock and distance to the road on non-native and native plant distributions. Our results confirm the largely negative relationship of non-native plant richness and cover with elevation, with a peak in richness and cover at low to intermediate elevations. Similarly, we show a strong decline in non-native richness with increasing distance to the road, especially at low elevations, accompanied by a strong negative effect of roads on native species richness. Most importantly, however, we show that the presence of non-native herbivores greatly increases the cover of non-native species away from the roadside, identifying herbivore disturbance as a potential catalyst of non-native plant invasion into natural vegetation of high-Andean protected areas. Our results confirm the often-shown role of disturbance as driver of plant invasions in mountains, yet highlight the interactive effects of disturbance by roads and herbivory: roads funnel non-native species towards higher elevations, while non-native herbivores can promote non-native plant success away from the roadside and into the natural vegetation. Hence, regulating soil and non-native herbivory disturbance is important for minimizing plant invasions at high elevation in the Arid Andes.