Abstract Phytophthora palmivora-induced root and basal stem rot pose a significant threat to the survival of Soe mandarin plants in East Nusa Tenggara Province, Indonesia. We isolated four Trichoderma species, five Bacillus, and 13 Pseudomonas isolates from the rhizosphere of healthy Soe mandarin. This study pursued two main objectives: (a) assessing the inhibitory capabilities of indigenous Trichoderma spp., Bacillus, and Pseudomonas towards P. palmivora in vitro, and (b) investigating the combined efficacy of Trichoderma spp., Bacillus, and Pseudomonas in controlling P. palmivora in a pot trial. Results revealed that four Trichoderma species (T. asperellum, T. hamatum, T. harzianum, and T. viride) significantly inhibited the growth of P. palmivora. Notably, T. asperellum exhibited the highest inhibition, at 84.31%, followed closely by T. harzianum (84.11%), T. viride (83.67%), and T. hamatum (80.28%). Bacillus and Pseudomonas exhibited varying levels of inhibition to P. palmivora growth in vitro, with the most substantial inhibition observed in Bacillus 1, followed by Pseudomonas 6. In the subsequent pot trial, the application of Trichoderma, Bacillus, or Pseudomonas, either individually or in combination, significantly increased the height increment and reduced the disease incidence caused by P. palmivora in Soe mandarin seedlings.

Abstract. Simamora AV, Hahuly MV, Nenotek PS, Kana YR, Kasim M, Pollo R, Ola AR, Pramatana F. 2024. In vitro screening of fungal endophytes from sandalwood (Santalum album) as antagonists to phytopathogens. Biodiversitas 25: 361-371. Endophytic fungi possess bioactive compounds and generate secondary metabolites like their host plants. The phytochemical compounds found in sandalwood plants (Santalum album L.) are recognized for their anti-pathogenic properties, suggesting the potential of sandalwood endophytic fungi as effective anti-phytopathogens. Alternaria solani and Fusarium oxysporum threaten tomato plants, whereas Phytophthora palmivora is particularly detrimental to cocoa plants. The aims of this study were: (i) to obtain isolates of endophytic fungi from roots, stems, and leaves of sandalwood plants and (ii) to assess the ability of endophytic fungi as anti-phytopathogens in vitro. Endophytic fungi were isolated through a direct plating method and next by purification and identification. All obtained endophytic fungi underwent testing for their antagonistic potential against A. solani, F. oxysporum, and P. palmivora in vitro through the dual culture method. The inhibition percentage was analyzed using variance analysis and further examined with the 5% HSD test. The study successfully isolated 104 endophytic fungal isolates from the sandalwood; 29 isolates were from the roots, 33 from the stems, and 42 from the leaves. All endophytic isolates demonstrated the ability to inhibit the growth of A. solani, F. oxysporum, and P. palmivora in vitro, with various inhibition percentages ranging from 26.7 to 83.3%. Further research will concentrate on secondary metabolites from selected isolates showing inhibition levels exceeding 70%.

Kegiatan Program Kemitraan Masyarakat ini bertujuan untuk meningkatkan pengetahuan dan keterampilan anggota Kelompok Tani Sion dalam budidaya tanaman Jeruk dan sayuran. Kelompok tani “Sion” berada di Dusun Upan, Desa Oelbubuk, Kecamatan Mollo Tengah, Kabupaten Timor Tengah Selatan. Kondisi budidaya tanaman jeruk pada umumnya sudah cukup baik, misalnya sudah dipasang perangkap lalat buah. Namun demikian, habitus pohon jeruk cukup rimbun karena tidak dipangkas. Petani masih belum menyadari pentingnya pemangkasan pembentukan kanopi. Kondisi budidaya sayuran masih perlu dioptimalkan, antara lain dengan membuat tempat rambatan dalam budidaya labu siam. Petani juga belum memanfaatkan mulsa plastik dalam budidaya sayuran semusim guna efisiensi sumber daya air dan tenaga kerja dalam pengendalian gulma. Berdasarkan kondisi di kelompok tani Sion tersebut, maka melalui kegiatan PKM ini dilakukan kegiatan pelatihan dan pendampingan pemangkasan tanaman jeruk, memperbaiki budidaya labu siam melalui pembuatan tempat merambatnya tanaman tersebut, penyuluhan tentang peranan mulsa dalam budidaya sayuran, dan pengaplikasiannya. Pada akhir kegiatan, para anggota kelompok tani telah mendapat pengetahuan dan keterampilan dalam hal pemangkasan dan perawatan tanaman jeruk, perbaikan budidaya labu siam melalui pembuatan tempat merambat tanaman dari bambu, serta penyadaran petani tentang manfaat mulsa plastik serta aplikasinya dalam budidaya sayuran. Secara keseluruhan, petani sangat antusias dan menerima introduksi teknologi yang disampaikan

Citrus is an important commercial crop in Timor Tengah Selatan, East Nusa Tenggara, Indonesia, but many trees are suffering a decline in health. As citrus is heavily dependent on arbuscular mycorrhizal fungi (AMF), this study investigated the abundance of AMF in the rhizosphere of healthy and declining trees in citrus orchards at 12 geographical locations. In each orchard, 6 soil and 6 root samples representing 3 healthy and 3 declining trees were collected. The soil was analyzed for AMF spore abundance as well as physical (texture) and chemical properties (organic carbon, nitrogen, phosphorus, potassium, pH, and soil exchangeable capacity), while the fine roots of citrus were assessed for colonization. The data were analyzed using analysis of variance (ANOVA) where the health condition of the trees was under the geographical location/site factor. The results showed that the abundance of AMF spores was significantly affected by the geographical location from where the soils were collected, but the health condition of the trees had no effect. However, AMF colonization was significantly affected by both site and tree health. The number of AMF morphotypes tended to be higher under healthy trees than under declining trees. Soil analysis indicated that soil fertility (N and organic C) may be important for tree health. These results provided a new perspective on the possible involvement of AMF and soil nutrients in citrus decline. Further studies are required to define the interactions between AMF, soil fertility, and disease incidence to identify strategies for managing citrus decline in the region.

Penelitian dilaksanakan untuk menentukan patogenisitas Botryodiplodia theobromae dalam menginfeksi batang cendana dan menguji kemampuan 10 isolat Trichoderma spp. dalam menghambat pertumbuhan dua isolat B. theobromae secara in vitro. Uji patogenisitas dilakukan dengan menginokulasi potongan isolat B. theobromae pada batang cendana. Uji antagonis dilakukan menggunakan metode kultur ganda dengan 10 isolat Trichoderma spp. dan dua isolat B. Theobromae sebagai kombinasi perlakuan. Hasil uji patogenisitas membuktikan bahwa B. theobromae menyebabkan gejala penyakit dimulai pada hari ke 30 setelah inokulasi. Hasil uji antagonis menunjukkan bahwa isolat-isolat Trichoderma spp. mampu menghambat pertumbuhan dua isolat B. theobromae melalui antibiosis dan kompetisi. Penghambatan terbaik terhadap B. theobromae Bt01 dicapai oleh T. viride TVJKS (53.20%), sedangkan penghambatan terbaik terhadap B. theobromae Bt02 dicapai oleh T. hamatum THAK (53.26%).

Sub-districts Kie and Fatumnasi are two sub-districts in mainland West Timor that cultivate local potatoes from Soe. This germplasm needs to be preserved and developed to diversify non-rice alternative food. One of the main obstacles in cultivating potatoes is the presence of pests, but so far there have been no reports of pests on local potato plants from Soe from the two sub-districts, so this research needs to be done. This study aimed at an inventory of important pests on local potato plants from Soe as a database for early detection to prevent the occurrence of explosive pests. This research was conducted on potato plantations in Fatuulan Village, Ayofanu Village, Nunleu Village, and Nenas Village. The method used is a purpose survey at a specified sample point. A sampling of insect pests is done by direct observation and insect nets. The pests found were put in a killing bottle or 70% alcohol, collected, and identified. Observation variables include the type of pest, symptoms of pest attack, and morphological characteristics of the stadia found. The data obtained were analyzed descriptively. The results showed that five species of pests damaged local potatoes from Soe. The five pests were Spodoptera litura, Henosepilachna vigintioctomaculata, Liriomyza sp, Phthorimaea operculella, and Nezara viridula. The identification results showed that in Kie District there were three pest species, namely S. litura, H. vigintioctomaculata, and Liriomyza sp. Meanwhile, in Fatumnasi District, there were four types of pests, namely H. vigintioctomaculata, Liriomyza sp, P. operculella, and N. viridula

Kelompok Tani Sion terletak di Desa Oelbubuk Kecamatan Mollo Tengah. Tanaman yang dibudidayakan adalah jeruk, cabai, tomat, bawang merah, bawang putih, kubis, sawi, dan petsai. Kelompok Tani ini mempunyai 20 anggota aktif dan diketuai oleh Ibu Demsi Talak. Berdasarkan survei yang dilakukan pada awal Maret 2022, diketahui bahwa tanaman petani umumnya tanpa pemupukan dan perawatan maksimal. Kalaupun ada pemupukan, biasanya menggunakan pupuk kimia. Para petani/anggota kelompok tani juga belum memahami manfaat trichokompos/pupuk organik bagi tanaman, lingkungan, dan kesehatan manusia. Untuk menjawab permasalahan mitra maka solusi yang akan dilakukan dalam program PKM ini adalah memberikan pencerahan kepada kelompok sasaran tentang teknik budidaya sayuran dan pembuatan pupuk organik trichokompos. Solusi tersebut dapat dijawab dengan dua pendekatan yaitu 1) penyuluhan dan demplot penanaman sayuran, 2) pembuatan pupuk organik trichokompos. Tim pelaksana melakukan pendampingan sampai kelompok mitra dapat mencapai tujuan pelaksanaan program. Evaluasi dilakukan secara bersama- sama untuk memperbaiki teknologi yang mengalami hambatan. Hasil kegiatan, diskusi, dan evaluasi menunjukkan sebanyak 82% kelompok sasaran memahami manfaat negatif dari input bahan kimia (pupuk dan pestisida) pada tanaman. Selanjutnya, sebanyak 75% angota kelompok berkomitmen untuk membuat dan mengaplikasikan trichokompos pada tanaman mereka. Harapan kelompok masyarakat sasaran adalah dapat mengkomersilkan trichokompos yang dihasilkannya ke masyarakat di sekitarnya.

Abstrak Kegiatan Program Kemitraan Masyarakat ini bertujuan untuk memberikan solusi terhadap permasalahan yang selama ini dihadapi kelompok tani Iklas di Desa Tubuhue Kecamatan Amanuban Barat, Kabupaten Timor Tengah Selatan. Permasalahan yang dihadapi antara lain berupa keterbatasan dalam cara pemeliharaan tanaman apel dan sayuran, serta dalam hal pengendalian hama penyakit tanaman. Kegiatan PKM ini bertujuan untuk: (1) memperkenalkan metode budidaya tanaman secara sehat berkelanjutan; (2) membuat Trichokompos menggunakan isolat Trichoderma sp. koleksi Laboratorium Penyakit Tumbuhan Faperta Undana; (3) membuat dan mengaplikasikan pupuk organik cair dari limbah pertanaman dan peternakan yang diperkaya dengan EM4; (4) membuat perangkap lalat buah; dan (5) membuat dan mengaplikasikan pestisida nabati. Metode pelaksanaan adalah penyuluhan, diskusi, praktek, dan pembuatan demplot.Target kegiatan PKM ini telah tercapai. Petani telah menguasai pengetahuan tentang budidaya tanaman secara sehat serta dapat membuat Trichokompos dan pupuk organik cair dan telah mengaplikasikannya.Sayuran yang diberi perlakuan Trichokompos dan pupuk organik cair tumbuh lebih subur dibandingkan dengan yang tidak diberi perlakuan. Petani antusias dan bersemangat untuk melanjutkan praktek budidaya tanaman secara sehat tersebut. Kata kunci:Trichokompos, pupuk organik cair, metode budidaya tanaman sehat Abstract This Community Partnership Program was aimed to provide solutions to the problems in Iklas farmer group in Tubuhue Village, West Amanuban District, Timor Tengah Selatan Regency. The problems include limitations in methods for cultivating apple and vegetable crops, as well as for controlling plant pests and diseases. This Community Partnership Program activity was carried out to introduce sustainable plant cultivation method, to produce trichoderma biofertilizers using Trichoderma sp. collection of the Plant Disease Laboratory of Agriculture Faculty Universitas Nusa Cendana, to produce liquid organic fertilizer from crop and livestock waste enriched with EM4, as well as to make fruit fly traps and botanical pesticides. This program was done through counseling, discussion, practice, and making demonstration plots. The target of this Community Partnership Program has been achieved. Farmers have received knowledge about healthy and sustainable crop cultivation. Farmers have been able to make Tichompost and liquid organic fertilizer and have applied it to apples and various vegetables. Vegetables that were treated with Trichompost and liquid organic fertilizer grew more fertile than those that were not treated. Farmers were enthusiastic and willing to continue the practice of the healthy and sustainable crop cultivation. Keywords:trichocompost,liquid organic fertilizer, healthy crop cultivation method

This paper’s working hypothesis is that the indigenous farming practices of Timorese farmers are those most suitable and adaptable with regard to these farmers’ circumstances. Intensive farming and the acceleration of land conversion in Java lead to a reduction in favorable cropland and the degradation of soil biology. To meet the demand for food production, unfavorable areas outside Java, including marginal semi-arid areas on Timor Island, East Nusa Tenggara province, have become an important option. Unfortunately, the national crop production policy has paid less attention to the specific biophysical characteristics of the region and how local people have adapted to the diverse marginal environment. We review the literature in the areas of soil nutrition retention and soil biology, vegetation/crop diversity, and farming practices/management, including local wisdom on soil management. This paper highlights that the values of the chemical parameters of the soils in question are varied, but generally range from low to high. The existence of beneficial micro-organisms is important both for improving soil fertility and due to their association with local vegetation/crops. Traditional farming practices, such as the local agroforestry of Mamar, have effectively preserved the existence of micro-organisms that promote conservation practices, crop/vegetation diversity, and sustainable agriculture. We recommend that the expansion of croplands and crop production into marginal semi-arid areas needs to be considered and adapted while taking into consideration sustainability and environmentally sound traditional practices.

Abstrak Penduduk Desa Fatulan umumnya bermata pencarian sebagai petani tanaman pangan dan hortikultura. Hasil pertaniannya adalah kentang, bawang putih , bawang merah, kacang merah, wortel, jeruk keprok Soe dan aneka sayuran seperti sawi dan kacang panjang. Potensi alam tersebut sangat mendukung perkembangan sektor pertanian dan industri wisata dalam meningkatkan pendapatan masyarakat. Hasil pertanian dijual ke pasar-pasar tradisional di sekitar Kabupaten Timor Tengah Selatan (TTS). Fatuulan adalah pemasok utama komoditi hortikutura terutama kentang lokal, bawang merah dan kacang merah. Tetapi, produksi pertanian tersebut masih tergolongi rendah karena umumnya pengetahuan dan keterampilan petani dalam kegiatan budidaya tanaman masih rendah seperti rendahnya pengetahuan petani tentang pupuk dan pemupukan, serta pengendalian hama dan patogen tanaman. Masalah-masalah utama yang dihadapi mitra adalah: (a) belum mengetahui dan memanfaatkan pupuk organik serta mengandalkan penggunaan pupuk sintetis, (b) belum mengetahui tentang hama dan patogen yang menyerang tanaman, dampak negatifnya, dan teknik pengendalian hama dan patogen. Tujuan pelaksanaan Program Kemitraan Masyarakat (PKM) ini adalah untuk memberikan edukasi dan alih teknologi metode budidaya tanaman sehat dengan aplikasi pupuk organik trikokompos, pemanfaatan metil eugenol sebagai pemerangkap lalat buah, dan aplikasi pestisida nabati dalam pengelolaan hama dan penyakit tanaman. Melalui kegiatan ini diharapkan pengetahuan dan keterampilan petani dalam budidaya tanaman sehat dapat meningkat. Kata Kunci: Desa Fatuulan, PKM, pupuk trichokompos. ABSTRACT The residents of Fatulan Village generally make a living as farmers of food crops and horticulture. Fatuulan's agricultural products are local potatoes, local garlic, shallots, red beans, carrots, Soe tangerines, and various vegetables such as mustard greens and long beans. This natural potential dramatically supports the development of the agricultural sector and the tourism industry, increasing village income and the community's economy. Agricultural products obtained are sold to traditional markets around Timor Tengah Selatan Regency (TTS), and Fatuulan is the leading supplier of horticultural commodities, especially local potatoes, shallots, and red beans. However, agricultural production is still relatively low. In general, the knowledge and skills of farmers in plant cultivation activities are still low, such as the insufficient knowledge of farmers about fertilizers and fertilization and the absence of pest and pathogen control. The main problems faced by partners are: (a) not knowing and utilizing organic fertilizers and relying on synthetic fertilizers, (b) not knowing about pests and pathogens that attack plants, their negative impacts, and pest and pathogen control techniques. This PKM activity aims to provide education and transfer technology to healthy plant cultivation methods using trichocompost organic fertilizer application, utilization of methyl eugenol as a fruit fly trap, and application of botanical pesticides to manage pests and plant diseases. This activity is expected to increase the knowledge and skills of farmers in plant cultivation and pest control on their farms. Keywords: Fatuulan Village, PKM, trichocompost fertilizer.

Abstract. Mukkun L, Kleden YL, Simamora AV. 2021. Detection of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in maize field in East Flores District, East Nusa Tenggara Province, Indonesia. Intl J Trop Drylands 5: 20-26. Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is a pest originating from America and rapidly spread to various parts of the world, including Indonesia. In January 2020, armyworm attacks appeared on maize plantations in several districts in East Nusa Tenggara Province, Indonesia one of which is in East Flores District. This study aimed to identify S. frugiperda occurrence in East Flores District and to determine the damage intensity of S. frugiperda and the population of larvae on the maize plant. The maize fields were surveyed, and purposive sampling technique was used to assess the maize plants damaged by armyworm. Observations were made on the symptoms of the damage, identification of armyworm species, percentage of attacked corn plants, the intensity of the infestation, and maize cultivars planted by farmers. The results showed that S. frugiperda caused severe damage of 85 to 100% of the cultivated maize plants with damage intensity on a scale of 6 to 9. The larval population was relatively high, ranging from 1 to 28 per plant with an average of 6.65 in West Solor Subdistrict, while in Ile Mandiri Subdistrict, it ranged from 1 to 7 larvae per plant with an average of 2.55 per plant on heads.

Abstract. Simamora AV, Hahuly MV, Henuk JBD. 2021. Endophytic fungi as potential biocontrol agents of Phytophthora palmivora in the cocoa plant. Biodiversitas 22: 2601-2609. In Indonesia, the cocoa tree is one of the essential cultivation crops for farmers. Despite the importance of cocoa cultivation in Indonesia's economy, the productivity of this crop has declined. Cocoa black pod disease caused by Phytophthora palmivora (Butl.) is one of the most severe diseases affecting this crop worldwide, with average annual losses above 40%. Instead of using manufactured chemicals, biological control is an effective and eco-friendly alternative control measure against plant pathogens. This work aimed to assess the potential of endophytic fungi isolated from healthy cocoa pods to control Phytophthora palmivora in vitro and in vivo. Endophytic fungal isolates were classified based on the morphological characteristics of their cultures and reproductive structures. All isolates found were tested to inhibit P. palmivora in the dual culture method, and the best 10 isolates were continued for detached pod assay. Then, the best five isolates (Aspergillus4, Aspergillus5, Aspergillus6, Fusarium6, Ramichloridium sp.) were evaluated for their capability to reduce P. palmivora in cocoa seedlings and in the field plants. Aspergillus, Fusarium, and Ramichloridium showed maximum activity against P. palmivora in dual culture, pod, and seedling assays. Nevertheless, when all these five isolates were applied in the field, they did not suppress the disease development.

Abstrak Kelompok Tani Sion merupakan salah satu kelompok yang membudidayakan empat jenis tanam jeruk yaitu jeruk keprok SoE (JKS), jeruk hikson, jeruk siam, dan jeruk nipis. Berbagai jenis OPT yang memengaruhi pertumbuhan dan perkembangan jeruk diantaranya Phtytopthora sp., Diplodia sp, virus triteza, Scirtotfrips citri, Diaprina citri, lalat buah. Masalah lain yang dihadapi oleh mitra adalah tidak memberikan pupuk bagi tanaman. PKM ini bertujuan untuk membimbing, membina, dan memberdayakan petani mengelola hama penyakit jeruk ramah lingkungan dengan menggunakan pupuk hayati dan biopestisida. Menjawab permasalahan petani metode yang digunakan adalah yaitu penyuluhan dan pelatihan, adobsi dan introduksi teknologi (demplot dan percobaan terapan teknologi yang murah dan ekonomis serta ramah lingkungan); dan pemberdayaan anggota kelompok tani melalui pendampingan dan evaluasi oleh tim pelaksana. Hasil pelaksanaan menunjukkan bahwa sebanyak 40% anggota kelompok tani mengenal jenis hama dan penyakit pada jeruk, 70% anggota kelompok dapat membuat pupuk hayati tricokompos, pupuk organik cair, dan pestisida nabati. Sebanyak 60% petani mengaplikasikan tricokompos pada tanaman jeruk dan beberapa jenis tanaman lainnya seperti cabai. Abstract The Sion Farmers Group is one of the groups that cultivate four species of citrus, namely Soe Mandarin, hikson oranges, Siamese oranges, and limes. Various species of pests and dieases that affect the growth and development of citrus include Phytopthora sp., Diplodia sp., Triteza virus, Scirtotfrips citri, Diaporina citri and fruit flies. Another problem faced by parteners is not providing fertilizer for plants. This community partnership program aims to guide, foster, and empower farmers to manage environmentally friendly citrus pests using biological fertilizers and biopesticides. Answering farmers’ problems, the methods used are counseling and training, adoption and introduction of technology (demonstrations and experiments on the applications of cheap and economical technology as well as environmentally friendly); and emprowerment of farmer group members through mentoring and evaluation by the implementing team. The results of the implementation showed that as many as 40% of farmer group members knew the species of pests and diaseases in citrus, 70% of group members could make tricocompost biofertilizer, liquid organic fertilizer, and botanical pesticides. As many as 60% of farmers apply tricocompost on citrus plants and several other species of plants such as chili.

Mangrove forest has a distinctive habitat adapting with marine and terrestrial environment. Chemical investigation of the extract from mangrove endophytic fungi Nigrospora oryzae had resulted in the isolation of sterigmatocystin (1) and pestalopyrone (2). The structure of sterigmatocystin (1) and pestalopyrone (2) were elucidated using mass, UV and NMR spectrometers together with the comparison with the literature data. The study also showed that sterigmatocystin displayed moderate cytotoxicity but it could be further developed as antiviral and antibacterial agent based on the SAR information reported from its analogue and derivatives.

Penelitian ini dilakukan dengan tujuan untuk mengetahui pengaruh capital intensity, profitabilitas dan leverage baik secara simultan maupun parsial terhadap agresivitas pajak. Populasi dalam penelitian ini adalah perusahaan sub sektor makanan dan minuman yang terdaftar di Bursa Efek Indonesia (BEI) periode 2015-2018. Penelitian ini menggunakan metode kuantitatif. Teknik pengambilan sampel menggunakan purposive sampling dan didapat 11 perusahaan dengan periode empat tahun sehingga jumlah sampel penelitian adalah 44 sampel dalam penelitin ini. Metode analisis data dalam penelitian ini menggunakan analisis regresi data panel dengan aplikasi Eviews 9. Hasil pengujian secara parsial, menunjukkan bahwa capital intensity dan leverage tidak berpengaruh terhadap agresivitas pajak. Sedangkan profitabilitas berpengaruh terhadap agresivitas pajak. Hasil pengujian secara simultan, menunjukkan bahwa capital intensity, profitabilitas dan leverage berpengaruh terhadap agresivitas pajak.

A detailed site investigation of a eucalypt nursery suffering disease losses revealed the causal agent to be Phytophthora boodjera. The pathogen was detected in vegetation surrounding the nursery production area, including the lawn, under the production benches during the growing season, and, most importantly, from plant debris in used trays. However, it was not found in the container substrate, water supplies, or production equipment or on the workers themselves. The sterilization methods used by the nursery were shown to be ineffective, indicating that a more rigorous method was required. Boiling trays for 15 min or steaming at 65°C for 60 min eradicated P. boodjera. This pathogen was more pathogenic to the eucalypts tested in their early seedling stage than P. cinnamomi. Tracing of out-planting to revegetation sites showed that P. boodjera was able to spread into the environment. Dispersal via out-planting to native vegetation may affect seedling recruitment and drive long-term shifts in native plant species. Inadequate nursery hygiene increases the risk of an outbreak and can limit the success of biosecurity efforts as well as damage conservation efforts.

During routine vegetation health surveys in the southwest of Western Australia (SWWA), several Phytophthora isolates with affinity to Clade 6a have been recovered. In this study, all known taxa from Clade 6a, P. inundata, P. humicola, P. gemini, P. ‘walnut’ and P. ‘personii’, and the new isolates were compared based on morphology and DNA sequence data from three nuclear genes and two mitochondrial genes resulting in the description of five new species, P. balyanboodja, P. condilina, P. cooljarloo, P. kwongonina and P. pseudorosacearum. With the exception of P. gemini and P. humicola, all species from Clade 6a have been recovered from natural ecosystems in SWWA. These species are morphologically similar, with predominantly ovoid sporangia and nested and extended internal proliferation. If oospores are present, they tend to be aplerotic with paragynous antheridia mostly attached adjacent to the oogonial stalk. They can all grow at 35 °C and have a fast growth rate on most agar media. These species have all been recovered from the rhizosphere soil and dead and dying plants within dry kwongon heathlands, often from water gaining sites and frequently from very isolated areas. The radiation, origin and potential ecological role of these species are discussed.

Phytophthora boodjera is a newly described pathogen causing damping off and mortality of Eucalyptus seedlings in Western Australian nurseries. This study evaluated the age-related susceptibility of several taxa of mallee Eucalyptus to P. boodjera in sterilized washed river sand-infestation pot trials. Phytophthora cinnamomi and P. arenaria were included for comparison. Seedlings of Eucalyptus taxa were inoculated at 0, 2, 4, 12 and 88 weeks with individual Phytophthora isolates. Pre-emergent mortality in the presence of Phytophthora was almost 100%. Post-emergent mortality was 50-100%, depending on isolate, compared to 0% for the control. Mortality was also high for inoculated 1 month-old seedlings (46-68%) and root length of surviving seedlings was severely reduced. Death from root infection was not observed for seedlings inoculated at 12 and 88 weeks, but they developed root necrosis and reduced root dry weight compared to non-inoculated controls. Phytophthora boodjera is a pre- and post-emergent pathogen of mallee eucalypts. These eucalypts are susceptible to P. boodjera at all life stages tested, but the mortality rates declined with plant age. Similar results were obtained for P. cinnamomi and P. arenaria. The events leading to its recent appearance in the nurseries remain unknown and further investigations are underway to determine if this is an introduced or endemic pathogen. The approach used here to understand the impact of a Phytophthora species on multiple hosts at different seedling ages is novel and sets a benchmark for future work.

A new homothallic Phytophthora species, isolated in Western Australia (WA), is described as Phytophthora boodjera sp. nov. It produces persistent, papillate sporangia, oogonia with thick-walled oospores, and paragynous antheridia. Although morphologically similar to P. arenaria, phylogenetic analyses of the ITS, cox1, HSP90, ß-tubulin and enolase gene regions revealed P. boodjera as a new species. In addition, P. boodjera has a higher optimal temperature for growth and a faster growth rate. Phytophthora boodjera has only recently been found in Western Australia and has mostly been isolated from dead and dying Eucalyptus seedlings in nurseries and from urban tree plantings, and occasionally from disturbed natural ecosystems. It is found in association with declining and dying Agonis flexuosa, Banksia media, B. grandis, Corymbia calophylla, Eucalyptus spp,. and Xanthorrhoea preissii. The status of P. alticola was also reviewed. The loss of all isolates associated with the original description except one; discrepancies in both sequence data and morphology of the remaining isolate with that presented the original description, and inconclusive holotype material places the status of this species in doubt.