Ketahanan  Delapan Klon Abaka (Musa textilis) Terhadap Fusarium oxysporum F sp. cubesence

Penyakit layu Fusarium pada tanaman Abaka (Musa textilis L.) yang disebabkan oleh Fusarium oxysporum f sp. cubesence (Foc) merupakan salah satu kendala terhambatnya perkembangan Abaka di Indonesia karena menyebabkan penurunan kualitas serat. Gejala serangan Foc adalah terbelahnya batang semu bagian luar dan warna daun berubah menjadi kuning pucat sampai kuning kecoklatan kemudian layu. Indonesia belum memiliki varietas unggul untuk mendukung pengembangan Abaka, meskipun Balittas memiliki koleksi plasma nutfah yang cukup. Tulisan ini bertujuan untuk memberikan informasi ketahanan delapan klon Abaka yang memiliki potensi produksi tinggi terhadap infeksi Foc. Penelitian dilakukan di rumah kaca Balittas pada tahun 2018. Sebanyak delapan klon abaka (UB4, Tangongon, Tangongon 70-3-1-1-2, UB-7, Cilacap, UB-8, UB-11, dan UB-5) yang diuji disusun dalam Rancangan Acak Kelompok dengan tiga kali ulangan. Isolat Foc yang digunakan berasal dari tanaman abaka yang menunjukkan gejala layu Fusarium. Masing-masing klon ditanam dalam polibag berukuran 500 g satu tanaman per polibag. Setiap klon ditanam sebanyak 10 polibag per ulangan. Benih abaka berumur 3 bulan direndam selama 24 jam dalam suspensi konidia Foc dengan kerapatan105/ml. Pengamatan kejadian penyakit dilakukan setiap 5 hari sekali sampai tanaman berumur 60 hari. Hasil penelitian menunjukkan bahwa, tidak ada klon abaka yang diujikan tahan terhadap Foc melainkan rentan (UB8 dan Tangongon) dengan tingkat kejadian penyakit 43,3% - 46,7% dan sangat rentan (Cilacap, UB4, Tangongon 70-3-1-1-2, UB-7, UB-11, dan UB-5) dengan tingkat kejadian 56,7% - 96,7%.<div><hr align="left" size="1" width="33%" /><div> </div></div>Resistance of Eight Clones of Abaca (Musa textilis) to Fusarium oxysporum F sp. cubesenceABSTRACT.Fusarium wilt on Abaca (Musa textilis L.) caused by Fusarium oxysporum f sp. cubesence (Foc) was one of the obstacles to development of Abaca in Indonesia since it decreased fibre quality. Symptom of Foc infection was splitted of the outer low pseudostem and discoloured of the leaf sheat to pale yellow or brownish yellow and then wilt. Indonesia has not released a superior variety (ies) to support the development of Abaca, although Balittas has enough germplasm collection. This paper reported the resistance of eight Abaca clones, which have high potential production, to Foc. The trial activity has been conducted in the screen house of BALITTAS in 2018. The tested clones were: UB4, Tangongon, Tangongon 70-3-1-1-2, UB-7, Cilacap, UB-8, UB-11, and UB-5 which was arraned in randomized block design with three replicates. Foc was isolated diseased abaca with wilt and yellow leaf symptom. Each clone was grown in sterilised soil in a 500 g polybag, with 10 three months old plants for each replicate. The plants were soaked in conidial suspension (105/ml) for 24 hours. Disease incidence was observed every five days for 60 days. Result of the test showed, none of the clones was resistant to Foc but susceptible (UB8 and Tangongon) with disease incidence rates of 43.3% - 46.7% and very susceptible (Cilacap, UB4, Tangongon 70-3-1-1 -2, UB-7, UB-11, and UB-5) with an incidence rate of 56.7% - 96.7%, respectively.

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POTENTIAL OF PLANT EXTRACTS AND FUNGICIDES FOR MANAGING FUSARIUM OXYSPORUM F. SPLYCOPERSICI

Pakistan Journal of Phytopathology ◽

10.33866/phytopathol.030.01.0450 ◽

2018 ◽

Vol 30 (1) ◽

pp. 75 ◽

Cited By ~ 1

Author(s):

Gul B. Poussio ◽

Manzoor A. Abro ◽

Jamal U. D. Hajano ◽

Muhammad I. Khaskheli ◽

Khalid I. Rajput ◽

...

Keyword(s):

Fusarium Oxysporum ◽

Mycelial Growth ◽

Disease Incidence ◽

Block Design ◽

Fungal Growth ◽

Tomato Crop ◽

Randomized Block Design ◽

Sindh Province ◽

Causal Fungus

Fusarium oxysporum f.sp. lycopersici (FOL) is a highly destructive fungal pathogen of tomato crop causing wilt disease which may reduce 10 to 90% yield. In Pakistan, tomato is widely grown in Sindh province, major territories are district Hyderabad, Tando Allahyar and Mirpurkhas. Thus, surveys of these territories were conducted to record intensity of the disease and confirm etiology. Furthermore, potential of different botanical pesticides and commercially available fungicides were tested to inhibit mycelial growth of the causal fungus. The experiment was laid down with complete randomized block design with three replications. The results showed that the disease was occurring in all locations with the range of 8-47 % incidence. F. oxysporum f.sp. lycopersici was predominantly isolated from the collected disease sample during survey and pathogenic nature of the fungus was tested on the tomato Golo variety through soil drenching method. The disease incidence of 30 and 42 % (72 % as total) was recorded in inoculated tomato plants at 20 and 40 DAI, respectively. Maximum (67 %) inhibition of the fungal growth was found by neem seed extracts at higher dose of 8 % concentration followed by 63 % with neem seeds and Eucalyptus at 6 and 8 %, respectively. Alternatively, the Nativo 75 WG fungicide was found most effective in reducing the redial mycelial growth of target fungus followed by Topsin-M at 1000 ppm where as Aliette and Melodedue fungicides were found least effective under in-vitro conditions.

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Generation Mean Analysis in Cowpea [Vigna unguiculata (L.) Walp.] under Flower Thrips infestation

Journal of Agricultural Science ◽

10.5539/jas.v10n4p86 ◽

2018 ◽

Vol 10 (4) ◽

pp. 86 ◽

Cited By ~ 1

Author(s):

Gonné Sobda ◽

Fonji Maureen Atemkeng ◽

Ousmane Boukar ◽

Chistian Fatokun ◽

Pangirayi Bernard Tongoona ◽

...

Keyword(s):

Block Design ◽

Generation Mean Analysis ◽

Flower Number ◽

Narrow Sense Heritability ◽

Gene Effects ◽

Flower Thrips ◽

Randomized Block Design ◽

Cowpea Resistance ◽

Predominant Type ◽

Screen House

Two sets of six generations (P1, P2, F1, F2, BC1P1, BC1P2) of cowpea were developed from crosses of contrasting inbred lines VYA (susceptible) × SANZI (resistant) and LORI (susceptible) × SANZI (resistant). The aim of this study was to determine the inheritance and elucidate the genetic control of cowpea resistance to thrips. The first set (VYA × SANZI) was evaluated under natural thrips infestation in the field in a completely randomized block design with three replications. The second set (LORI × SANZI) was screened using artificial thrips infestation in the screen house. In each trial, data were recorded on 150 individual plants. These included the score of thrips damages using the scale of one to nine, number of thrips per flower, number of pods per plant, pod weight per plant and grain weight per plant. The generation mean analysis revealed that both additive and non-additive types of gene effects were significant. Dominance × dominance was the most predominant type of gene effects for thrips resistance, suggesting that breeders should delay selection to late generations to allow advancement of as many high-potential recombinants as possible during hybridization. The number of genes that control the expression of number of thrips per flower was three and ranged from three to four, for score of thrips damages. High broad sense and moderate narrow sense heritability were observed ranging from 0.53 to 0.65 and 0.14 to 0.36, respectively for all of the traits measured.

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PHYSIOLOGICAL POTENTIAL AND CONSERVATION OF MURUCI (Byrsonima crassifolia) SEEDS

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452017475 ◽

2017 ◽

Vol 39 (5) ◽

Author(s):

CAMILA RIBEIRO DE SOUZA GRZYBOWSKI ◽

WALNICE MARIA OLIVEIRA DO NASCIMENTO ◽

ROSEMEIRE CARVALHO DA SILVA ◽

ELISA SERRA NEGRA VIEIRA ◽

MARISTELA PANOBIANCO

Keyword(s):

Block Design ◽

Rapid Assessment ◽

Germplasm Collection ◽

Germination Test ◽

Byrsonima Crassifolia ◽

Randomized Block Design ◽

Relative Air Humidity ◽

Different Temperatures ◽

Mother Plants ◽

Tetrazolium Test

ABSTRACT The goal of the present study is to assess the physiological potential of Byrsonima crassifoliaseeds and analyze the procedures of the germination and tetrazolium tests, as well as the conservation of such seeds by testing different combinations of packaging and environment. The experiment used pyrenes of the clone Açu, collected from mother plants in the germplasm collection of muruci plants of Embrapa Amazonia Oriental, in Belém, Brazil. Different temperatures were tested in the germination test (25, 30, 35 and 20 - 30 ºC). The best methodology and assessment dates were determined for the test, and the seedlings of the species were characterized. Viability was assessed with the tetrazolium test, with combinations of hydration methods (by immersion and between paper towels), staining periods (3 and 4 h) and concentrations of tetrazolium solution (0.5, 0.7 and 1.0%). Storage of muruci pyrenes was evaluated at three, six and twelve months, in polyethylene and Kraft paper bags, under dry chamber and refrigerator conditions. The study used a randomized block design with four replicates. The data underwent analysis of variance. In conclusion, the physiological potential of seeds of B. crassifoliacan be assessed by the germination test conducted in sand, with alternating temperatures of 20-30 ºC, or with the use of the tetrazolium test (with staining for three hours in the tetrazolium solution at 1.0%) as a rapid assessment of viability. Muruci pyrenes can be kept in polythene or paper Kraft bags for up to 12 months, in a dry chamber at 16 ºC and with relative air humidity of 50 to 60%.

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GGE Biplot projection in discriminating the efficiency of popcorn lines to use nitrogen

Ciência e Agrotecnologia ◽

10.1590/1413-70542017411030816 ◽

2017 ◽

Vol 41 (1) ◽

pp. 22-31 ◽

Cited By ~ 8

Author(s):

Adriano dos Santos ◽

Antônio Teixeira do Amaral Júnior ◽

Railan do Nascimento Ferreira Kurosawa ◽

Ismael Fernando Schegoscheski Gerhardt ◽

Roberto Fritsche Neto

Keyword(s):

Nitrogen Availability ◽

Block Design ◽

Germplasm Collection ◽

Inbred Lines ◽

Gge Biplot ◽

State University ◽

Information Ratio ◽

The North ◽

Randomized Block Design ◽

Main Components

ABSTRACT Nitrogen is essential for sustaining life on the planet, and it is the most important nutrient for obtaining high agricultural production. However, their use leads to the release of nitrous oxide with a global warming potential 296 times higher than the CO2 molecule, making it a challenge to reduce their use in agriculture. The objective of this research was to identify efficient popcorn inbred lines and responsive nitrogen use and exhibit a good expansion volume. For this, 29 inbred lines from the Germplasm Collection of Darcy Ribeiro North Fluminense State University (UENF) were evaluated at two contrasting levels of nitrogen availability (low and ideal) at two representative locations in the north and northwest of the state of Rio de Janeiro, Brazil, arranged in a randomized block design with three replicates. These inbred lines were discriminated against efficient use of nitrogen by multivariate GGE Biplot. Selective accuracy was close to 1, showing that the genotypes were enough to provide contrasting success in selection procedures. The first two main components (PC) retained 93.82% of the total variation, and PC1 furnished an information ratio (IR) that was unaffected by noise. L77 was the most unstable line, while P7, P2, P6, P3, P5, P4, P9, P10, P8, P9, L70, L74, and L55 were efficient and responsive. The GGE biplot method is recommended for the reliable identification of popcorn lines that are efficient and responsive to the use of nitrogen.

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REACTION OF BANANA CULTIVARS TO THE Meloidogyne javanica X Fusarium oxysporum f. sp. cubense COMPLEX

Revista Caatinga ◽

10.1590/1983-21252018v31n305rc ◽

2018 ◽

Vol 31 (3) ◽

pp. 572-583

Author(s):

LEANDRO DE SOUZA ROCHA ◽

ROBERT FELIX DE SANTANA ◽

ANA CRISTINA FERMINO SOARES ◽

FERNANDO HADDAD

Keyword(s):

Genetic Variability ◽

Fusarium Oxysporum ◽

Block Design ◽

Meloidogyne Javanica ◽

Simultaneous Presence ◽

Sterile Soil ◽

Panama Disease ◽

Randomized Block Design ◽

Resistant Varieties ◽

Inoculation Time

ABSTRACT The interaction Fusarium oxysporum f. sp. cubense (Foc) x nematode and the genetic variability of Foc are the main problems with potential to affect the use of resistant varieties in the management of the Panama disease. The objective of this work was to evaluate the interaction between Foc and Meloidogyne javanica on the banana of the Prata Anã, Grande Naine and BRS Princesa cultivars. The experiment was conducted in a randomized block design, with six treatments and ten replications, which differed in the inoculation time of each pathogen. Simultaneous inoculation with Foc and M. javanica, inoculation with Foc one week before inoculation with M. javanica, and inoculation with M. javanica one week before inoculation with Foc. In addition to the controls, Foc isolated, M. javanica isolated, and cultivars without the pathogens. The seedlings were transplanted in 3-liter pots with sterile soil infested with 40 grams of Foc inoculum at the concentration of 1x106CFU/gram and 1000 eggs and J2 of M. javanica. At the end of 56 days, the treatments with 'Grande Naine' presented the highest reproduction factors of M. javanica. In the 'Prata Anã' no interaction was observed between Foc x M. javanica. The treatments with simultaneous inoculation of the two pathogens, and with Foc a week before, in the 'BRS Princesa', presented the highest external disease indices (DI), which promoted the highest AUDPC. The highest internal DI were observed in the treatments Foc+Mj+Grande Naine, Foc+Mj+BRS Princesa, Mj+Grande Naine+Foc and Foc+BRS Princesa+Mj. The simultaneous presence of M. javanica and Foc increases the severity of the Panama disease in Grande Naine and BRS Princesa cultivars.

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Genetics and expected selection gain for growth traits in Eugenia dysenterica DC. populations

Bragantia ◽

10.1590/s0006-87052009000300009 ◽

2009 ◽

Vol 68 (3) ◽

pp. 629-637 ◽

Cited By ~ 4

Author(s):

Ananda Virginia de Aguiar ◽

Roland Vencovsky ◽

Lázaro José Chaves ◽

Mara Fernandes Moura ◽

Lizz Kezzy de Morais

Keyword(s):

Genetic Variation ◽

Genetic Parameters ◽

Growth Traits ◽

Block Design ◽

Genetic Material ◽

Germplasm Collection ◽

Seed Orchard ◽

Seedling Seed Orchard ◽

Randomized Block Design ◽

Eugenia Dysenterica

The objective of this study was to estimate genetic parameters of quantitative traits in a living germplasm collection of Eugenia dysenterica. The genetic material consisted of 110 progenies derived from 10 natural Eugenia dysenterica subpopulations sampled in the southeastern region of the state of Goiás. The experiment was established in a complete randomized block design, with 110 treatments, four replications and one tree per plot. The study variables were total height, stem diameter and respective growth rates. After the analysis of variance some genetic parameters were estimated. The levels of genetic variation in the collection were high and the highest proportion was found within subpopulations. Highest coefficients of heritability and genetic variation were observed in subpopulations from the counties Catalão, Três Ranchos, Cristalina and Senador Canedo. Considering the promising expected progress for growth traits, this collection can be converted into an unrogued seedling seed orchard, aiming the production of improved seed.

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Fusarium oxysporum f. sp. phaseoli and Meloidogyne incognita interaction in common bean

Cropp Breeding and Applied Biotechnology ◽

10.1590/s1984-70332010000300014 ◽

2010 ◽

Vol 10 (3) ◽

pp. 271-274 ◽

Cited By ~ 3

Author(s):

Flávia Fernandes Carneiro ◽

Magno Antonio Patto Ramalho ◽

Mônica Juliani Zavaglia Pereira

Keyword(s):

Common Bean ◽

Fusarium Oxysporum ◽

Meloidogyne Incognita ◽

Tomato Plant ◽

Block Design ◽

Egg Mass ◽

One Pot ◽

Randomized Block Design ◽

Bean Plants ◽

Susceptible Tomato

To verify a possible relationship between resistance to nematodes and to Fusarium oxysporum (Fop) in common bean, 18 lines (eight resistant and eight susceptible to Fop plus two controls) were evaluated for resistance to the nematode Meloidogyne incognita. This evaluation was conducted in a greenhouse in a randomized block design with five replications. The plot consisted of one pot with two bean plants and a nematode-susceptible tomato plant. Two weeks after sowing, plants were infested in the rhizosphere with 5000 eggs of Meloidogyne incognita, race 3. The number of egg masses was assessed, about 45 days after inoculation. Only lines ESAL 522, ESAL 519 and 'Aporé' were resistant to the nematode. Only 'Aporé' was resistant to both pathogens. The correlation between grades of Fop severity and mean egg mass was practically zero (r = 0.0252, P < 0.9293).

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First Report on Ovate-leaf Atractylodes Damping-off Caused by Fusarium oxysporum species Complex in South Korea

Plant Disease ◽

10.1094/pdis-05-21-1107-pdn ◽

2021 ◽

Author(s):

Oliul Hassan ◽

Taehyun Chang

Keyword(s):

South Korea ◽

Fusarium Oxysporum ◽

Species Complex ◽

Disease Incidence ◽

Fusarium Species ◽

Morphological Characteristics ◽

Conidial Suspension ◽

Sterile Water ◽

Damping Off ◽

First Report

In South Korea, ovate-leaf atractylodes (OLA) (Atractylodes ovata) is cultivated for herbal medicine. During May to June 2019, a disease with damping off symptoms on OLA seedlings were observed at three farmer fields in Mungyeong, South Korea. Disease incidence was estimated as approximately 20% based on calculating the proportion of symptomatic seedlings in three randomly selected fields. Six randomly selected seedlings (two from each field) showing damping off symptoms were collected. Small pieces (1 cm2) were cut from infected roots, surface-sterilized (1 minute in 0.5% sodium hypochlorite), rinsed twice with sterile water, air-dried and then plated on potato dextrose agar (PDA, Difco, and Becton Dickinson). Hyphal tips were excised and transferred to fresh PDA. Six morphologically similar isolates were obtained from six samples. Seven-day-old colonies, incubated at 25 °C in the dark on PDA, were whitish with light purple mycelia on the upper side and white with light purple at the center on the reverse side. Macroconidia were 3–5 septate, curved, both ends were pointed, and were 19.8–36.62 × 3.3–4.7 µm (n= 30). Microconidia were cylindrical or ellipsoid and 5.5–11.6 × 2.5–3.8 µm (n=30). Chlamydospores were globose and 9.6 –16.3 × 9.4 – 15.0 µm (n=30). The morphological characteristics of present isolates were comparable with that of Fusarium species (Maryani et al. 2019). Genomic DNA was extracted from 4 days old cultures of each isolate of SRRM 4.2, SRRH3, and SRRH5, EF-1α and rpb2 region were amplified using EF792 + EF829, and RPB2-5f2 + RPB2-7cr primer sets, respectively (Carbone and Kohn, 1999; O'Donnell et al. 2010) and sequenced (GenBank accession number: LC569791- LC569793 and LC600806- LC600808). BLAST query against Fusarium loci sampled and multilocus sequence typing database revealed that 99–100% identity to corresponding sequences of the F. oxysporum species complex (strain NRRL 28395 and 26379). Maximum likelihood phylogenetic analysis with MEGA v. 6.0 using the concatenated sequencing data for EF-1α and rpb2 showed that the isolates belonged to F. oxysporum species complex. Each three healthy seedlings with similar sized (big flower sabju) were grown for 20 days in a plastic pot containing autoclaved peat soil was used for pathogenicity tests. Conidial suspensions (106 conidia mL−1) of 20 days old colonies per isolate (two isolates) were prepared in sterile water. Three pots per strain were inoculated either by pouring 50 ml of the conidial suspension or by the same quantity of sterile distilled water as control. After inoculation, all pots were incubated at 25 °C with a 16-hour light/8-hour dark cycle in a growth chamber. This experiment repeated twice. Inoculated seedlings were watered twice a week. Approximately 60% of the inoculated seedlings per strain wilted after 15 days of inoculation and control seedlings remained asymptomatic. Fusarium oxysporum was successfully isolated from infected seedling and identified based on morphology and EF-1α sequences data to confirm Koch’s postulates. Fusarium oxysporum is responsible for damping-off of many plant species, including larch, tomato, melon, bean, banana, cotton, chickpea, and Arabidopsis thaliana (Fourie et al. 2011; Hassan et al.2019). To the best of our knowledge, this is the first report on damping-off of ovate-leaf atractylodes caused by F. oxysporum in South Korea. This finding provides a basis for studying the epidemic and management of the disease.

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KETAHANAN DELAPAN KULTIVAR TEMBAKAU LOKAL BONDOWOSO TERHADAP TIGA PATOGEN PENTING (Ralstonia solanacearum, Pectobacterium carotovorum, DAN Phytophthora nicotianae)

Jurnal Penelitian Tanaman Industri ◽

10.21082/jlittri.v18n3.2012.89-94 ◽

2020 ◽

Vol 18 (3) ◽

pp. 89

Author(s):

TITIEK YULIANTI ◽

NURUL HIDAYAH ◽

SRI YULAIKAH

Keyword(s):

Ralstonia Solanacearum ◽

Block Design ◽

Production Quality ◽

Phytophthora Nicotianae ◽

Pectobacterium Carotovorum ◽

Resistance Level ◽

Stalk Rot ◽

Randomized Block Design ◽

Tobacco Production ◽

Screen House

ABSTRAK Tembakau bondowoso merupakan tembakau lokal rajangan yang berkembang di Kabupaten Bondowoso, Jawa Timur. Saat ini ada delapan kultivar dengan karakter produksi, mutu, dan ketahanannya terhadap penyakit yang berbeda. Layu bakteri (Ralstonia solanacearum), busuk batang berlubang (Pectobacterium carotovorum), dan lanas (Phytophthora nicotianae) merupakan penyakit yang sering menyebabkan turunnya produksi tembakau bondowoso. Evaluasi ketahanan delapan kultivar tembakau bondowoso (Samporis, Serumpung, Marakot, Samporis Lokal, Samporis AH, Samporis CH, Samporis B. Disbun, dan Deli) terhadap ketiga patogen tersebut dilaksanakan di laboratorium dan rumah kasa Balai Penelitian Tanaman Pemanis dan Serat (Balittas) mulai bulan April sampai dengan Oktober 2011. Penelitian terhadap ketiga patogen tersebut dilakukan secara terpisah. Masing-masing kultivar ditanam sebanyak 10 tanaman, 1 tanaman/polibag. Setiap perlakuan (kultivar) diulang 3 kali dan disusun dalam rancangan acak kelompok (RAK). Inokulasi R. solanacearum dan P. carotovorum dilakukan secara terpisah 24 jam sebelum transplanting. Inokulasi P. nicotianae dilakukan dengan dua cara, yaitu melalui akar dan pangkal batang. Inokulasi akar sama dengan cara inokulasi bakteri. Inokulasi pangkal batang dilakukan pada tanaman berumur 2 minggu setelah transplanting. Pengamatan intensitas penyakit dilakukan setiap minggu selama 11 minggu. Hasil penelitian menunjukkan bahwa kultivar Samporis CH, Samporis, dan Deli tahan terhadap P. carotovorum, R. solanacearum, dan P. nicotianae. Kultivar Samporis CH., Samporis, dan Deli ketahanannya lebih tinggi terhadap ketiga patogen, dengan intensitas penyakit berkisar antara 3,3%-6,7%. Kultivar Marakot sangat rentan terhadap ketiga patogen tersebut dengan tingkat keparahan ≥ 50%. Demikian pula kultivar Samporis AH yang rentan terhadap R. solanacearum, P. nicotianae dan P. carotovorum dengan intensitas penyakit 23,3-53,3%. Oleh karena itu, kultivar Samporis CH, Samporis, dan Deli cocok dikembangkan pada lahan endemik penyakit tular tanah di Kabupaten Bondowoso. Kata kunci: tembakau bondowoso, Pectobacterium carotovorum Phytophthora nicotianae, Ralstonia solanacearum, ketahananABSTRACT Bondowoso tobacco is a local type of sliced tobacco which is restrictedly cultivated in Bondowoso Regency, East Java. There are eight cultivars known, ie. Samporis, Serumpung, Marakot, Samporis Lokal, Samporis AH, Samporis CH, Samporis B. Disbun, and Deli with their own distinctive characters on their production, quality, and resistance to diseases. Bacterial wilt (Ralstonia solanacearum), hollow stalk rot (Pectobacterium carotovorum), and blackshank (Phytophthora nicotianae are the main cause of bondowoso tobacco production loss. Evaluation on the resistance level of the cultivars to the three pathogens above has been conducted at a laboratory and screen house scale in Indonesian Sweetener and Fibre Crops Research Institute from April to October 2011. The evaluation of each pathogen was conducted separately. Each evaluation of the pathogen per cultivar used 10 plants planted individually in a polybag. The experiment was arranged in a randomized block design with 3 replicates. R. solanacearum and P. carotovorum were separately inoculated on the test plants 24 h before transplanting. The inoculation of P. nicotianae was done twice via the root and stem. Disease intensity was observed weekly for 11 weeks. The results showed that Samporis CH, Samporis, and Deli cultivars were resistant to P. carotovorum, R. solanacearum and P. nicotianae, whereas Samporis and Deli cultivars were more resistant to the pathogens (disease intensity ranged 3.3-6.7%). Marakot cultivar was very susceptible to all of the three pathogens (disease intensity ≥ 50%). Similarly, Samporis AH cultivar was also susceptible to the pathogens with disease intensity ranged 23.3-53.3%. The study indicated that Samporis CH, Samporis, and Deli cultivars are suitable to be cultivated in the endemic soil born pathogen areas of Bondowoso Regency. Key words: bondowoso tobacco, Pectobacterium carotovorum, Phytophthora nicotianae, Ralstonia solanacearum, resistance

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COMPARISON OF TWO METHODS TO EVALUATE THE RESISTANCE OF HAZELNUT GENOTYPES TO EASTERN FILBERT BLIGHT

HortScience ◽

10.21273/hortsci.29.7.742d ◽

1994 ◽

Vol 29 (7) ◽

pp. 742d-742

Author(s):

C.J. Coyne ◽

D.C. Smith ◽

S.A. Mehlenbacher ◽

K.B. Johnson ◽

J.N. Pinkerton

Keyword(s):

Control Method ◽

Disease Incidence ◽

Block Design ◽

Relative Resistance ◽

Randomized Block Design ◽

Anisogramma Anomala ◽

Causal Fungus ◽

Second Year ◽

Eastern Filbert Blight ◽

High Doses

Resistant cultivars are a promising disease control method for eastern filbert blight, which is devastating hazelnut production in Oregon. In 1990, two studies were begun to evaluate the relative resistance of European hazelnut (Coyhls avellana) genotypes to the causal fungus, Anisogramma anomala. A randomized block design of 40 genotypes was planted using inoculated trees planted in the borders as the disease source. The first- and second-year disease incidence (percent) were compared to the published disease incidence (percent) based on exposing potted trees of 44 genotypes to high doses of inoculum. Disease incidence was significantly correlated between the two studies in 1991 (r =0.41, P = 0.02) and in 1992 (r =0.64, P = 0.001; rs = 0.35, 0.025 70% of the potted tree study. A plot of disease incidence in the field planting indicates that the inoculum was present throughout the blocks.

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