scholarly journals First Report of Phytophthora ramorum Infecting California Red Fir in California

Plant Disease ◽  
2010 ◽  
Vol 94 (9) ◽  
pp. 1170-1170 ◽  
Author(s):  
G. A. Chastagner ◽  
K. L. Riley
Keyword(s):  
Shoot Elongation ◽  
Phytophthora Ramorum ◽  
Fluorescent Light ◽  
Average Height ◽  
Tree Plantation ◽  
Usda Forest Service ◽  
Washington State University ◽  
Successful Isolation ◽  
Tall Tree ◽  
Plastic Bag

In May 2005, branches originating from five separate whorls below the terminal on a single California red fir (Abies magnifica) in a mixed grand fir (Abies grandis) and Douglas-fir (Pseudotsuga menziesii) Christmas tree plantation near Los Gatos, CA displayed wilting and dieback of new shoot growth. Brown dieback, delineated by needle loss, extended 6 to 8 cm into 1-year-old and sometimes 2-year-old growth. The ~7-year-old, 1-m tall tree was located near the edge of the plantation, beneath an overstory of California bay laurel (Umbellularia californica) trees that were infected with Phytophthora ramorum. Isolations from dieback margins onto corn meal agar amended with ampicillin, rifamycin, and pimaricin (CARP) yielded hyphae and large, dark brown chlamydospores that were morphologically consistent with P. ramorum (1). Microsatellite analysis confirmed that isolates were of the NA1 lineage of P. ramorum. Isolates were deposited in the Washington State University Puyallup Phytophthora Master Collection. Dormant bareroot California red fir seedlings were obtained from the USDA Forest Service Placerville Nursery (Camino, CA) in February 2006 and planted in SC-10 super cell cones (Stuewe & Sons, Inc., Tangent, OR) in a standard greenhouse potting mix. Seedlings (average height 11 cm) were then forced to initiate bud break and new shoot elongation (0.5 to 1.5 cm) in a greenhouse at 21°C. Eight unwounded seedlings were inoculated with a zoospore suspension (4.185 × 105 zoospores/ml of sterile water) produced from 3- to 4-week-old V8 juice agar cultures of isolate WSU#106-0021 using an artist's airbrush powered by Badger Propel canned propellant. Eight control seedlings were sprayed with water alone. Seedlings were placed in plastic tubs with ~2.5 cm of warm water in the bottom to provide humidity. A plastic bag supported by a wire frame was used to cover each tub. Tubs were placed in a biocontainment unit at 15 to 16°C under 24 h of fluorescent light. The plastic was removed after 5 days and seedlings were left under the same conditions. Seven days after inoculation, 25 to 100% (average 68%) of the new shoots on each of the eight inoculated seedlings were wilted and 100% of these seedlings exhibited dark brown dieback into the 1-year-old stems (range of 1.0 to 2.3 cm, average 1.6 cm). Tissues from shoots and dieback edges were plated onto CARP media. All of these attempts resulted in successful isolation of P. ramorum, and cultures exhibited the same hyphal morphology and chlamydospore characteristics when compared with the isolate tested. Control plants did not develop symptoms. This trial completes Koch's postulates to establish California red fir as a host of Phytophthora ramorum. To our knowledge, this site contains the only reported infection of California red fir by P. ramorum. The potential for infection within its native range is unknown. Reference: (1) S. Werres et al. Mycol. Res. 105:1155, 2001.

First Report of Phytophthora ramorum Infecting Grand fir in California

2011 ◽  
Vol 12 (1) ◽  
pp. 37
Author(s):  
Kathleen L. Riley ◽  
Gary A. Chastagner ◽  
Cheryl Blomquist
Keyword(s):  
Phytophthora Ramorum ◽  
Christmas Tree ◽  
Native Range ◽  
Tree Plantation ◽  
Koch’S Postulates ◽  
First Report ◽  
Stem Lesions ◽  
Koch's Postulates

Phytophthora ramorum was detected on grand fir in 2003 and 2005 in a Christmas tree plantation near Los Gatos, CA, in association with infected California bay laurel. Isolates derived from stem lesions were used to inoculate grand fir seedlings in two tests. Isolations from lesions on inoculated plants were positive for P. ramorum in both tests. This work provides the completion of Koch's postulates to establish grand fir as a host of P. ramorum. The potential for grand fir to be infected within its native range is unknown. Accepted for publication 1 February 2011. Published 1 April 2011.

scholarly journals First Report of Gray Mold Disease of Sponge Gourd (Luffa cylindrica) Caused by Botrytis cinerea in Taiwan

Plant Disease ◽  
2007 ◽  
Vol 91 (9) ◽  
pp. 1199-1199 ◽  
Author(s):  
Y. Ko ◽  
K. S. Yao ◽  
C. Y. Chen ◽  
C. H. Lin
Keyword(s):  
Botrytis Cinerea ◽  
Gray Mold ◽  
Spore Suspension ◽  
Fluorescent Light ◽  
Distilled Water ◽  
Luffa Cylindrica ◽  
First Report ◽  
Sponge Gourd ◽  
Plastic Bag ◽  
Central Taiwan

A disease of sponge gourd (Luffa cylindrica (L.) Roem., family Cucurbitaceae) has become a serious threat to sponge gourd production since 2003 in central Taiwan. Initially, symptoms appear as small, brown spots on the flower petals that spread to the entire flower and cause blossom blight within 2 to 3 days. Subsequently, the pathogen develops abundant mycelium and moves from the petals onto the fruits causing blossom end rot and fruit stem rot. Severely infected fruits become completely rotten and desiccate. Tissues were excised from diseased sponge gourd fruits (sampled from Fongyuan, located at 24.25°N, 120.72°E in Taichung County), immersed in a solution containing 3% sodium hypochlorite and 70% ethanol for 1 min, washed three times with sterile water, and then cultured on potato dextrose agar (PDA) medium. A fungus, identified as Botrytis cinerea, produced abundant mycelium on PDA medium when incubated under constant fluorescent light 185 ± 35 μE·m–2·s–1 at 24°C. The conidia were smooth, hyaline, and globoid or slightly ellipsoid. The conidia measured 9.5 to 19.3 μm (average 13.8 μm) long and 6.0 to 17.8 μm (average 10.1 μm) wide, dimensions that are similar to the descriptions of B. cinerea (11 × 11 to 15 μm) that causes gray mold of strawberry (2). The identity of B. cinerea was also confirmed by the production of numerous black sclerotia on PDA plates incubated either in the dark or under light at 20 to 24°C for 9 to 10 days. Koch's postulates were fulfilled by using 3-day-old mycelial agar discs of the fungus or a spore suspension containing 105 conidia per milliliter of distilled water as inoculum. Shallow (2 × 2 × 2 mm) incisions were made on fresh sponge gourd fruits with a sterile scalpel and inoculated with either a 5-mm mycelial disc or 0.5 ml of the spore suspension. Inoculated areas were covered with moist sterile cotton, and the fruits were enclosed in a plastic bag and incubated at 20 to 24°C for 3 days. Wounded fruits inoculated with PDA discs or sterile distilled water alone served as controls. Pathogenicity tests were performed three times using five fruits in each trial. Symptoms and signs of the disease similar to those described above were observed in all (100%) the inoculated fruits, while no symptoms developed in the control fruits. Reisolation from the inoculated fruits consistently yielded B. cinerea. Reciprocal inoculations on sponge gourd, guava, and strawberry with mycelial discs or spore suspensions of a B. cinerea isolate obtained from sponge gourd, guava, and strawberry showed cross pathogenicity among isolates and hosts. Important groups of plants that are attacked by B. cinerea are vegetables, small berry fruits, ornamentals, and bulbs (1). Though 80 species of host plants, mostly shrubs and nursery plants, were reported to be the host of B. cinerea in Taiwan (3), to our knowledge, this is the first report of gray mold disease affecting sponge gourd in Taiwan. References: (1) G. N. Agrios. Plant Pathology. Academic Press. San Diego, 2005. (2) J. L. Mass, ed. Page 56 in: Compendium of Strawberry Diseases. The American Phytopathological Society. St. Paul, MN, 1984. (3). Y. Ko et al. Plant Prot. Bull. (Taiwan) 37:439, 1995.

scholarly journals KAJIAN ELONGASI PADA TANAMAN IN VITRO GAHARU (Aquilaria beccariana van Tiegh)

2015 ◽  
Vol 2 (2) ◽  
pp. 65
Author(s):  
Yusuf Sigit Ahmad Fauzan ◽  
Edhi Sandra ◽  
Daru Mulyono
Keyword(s):  
In Vitro Propagation ◽  
Ex Situ Conservation ◽  
Shoot Elongation ◽  
The Other ◽  
Ex Situ ◽  
Average Height ◽  
Best Response ◽  
Speed Up ◽  
Number Of Segments

The population density of natural agarwood (Aquilaria beccariana) in Indonesia decreased to less than one tree per hectare. Efforts have been carried out on ex situ conservation of agarwood despite facing many obstacles. In vitro propagation is one alternative to speed up the recovery of natural agarwood populations. The purpose of this study was to obtain optimal elongation media for in vitro culture with addition of auxin and cytokinin, namely IBA, BAP and kinetin. The results showed that the best auxin-cytokinin combination was IBA 0.1 mg/L and BAP 0.05 mg/L. This combination increased the height and number of segments of A. beccariana with an average height of 1.64 cm and average number of sections of 6.40. It is suggested that this combination of IBA and BAP was the most effective compared to the other treatments. In addition, the combination of IBA 0 mg/L and BAP 0.03 mg/L gave rise to the best response to increase the number of shoots with an average of 1.91 shoots.Keywords: Aquilaria beccariana, shoot, elongation, auxin, cytokinin ABSTRAKKepadatan populasi gaharu (Aquilaria beccariana) alam di Indonesia kurang dari satu pohon per hektar. Upaya pelestarian gaharu ex situ telah banyak dilakukan tetapi masih banyak kendala. Perbanyakan gaharu in vitro merupakan salah satu cara alternatif untuk mempercepat pemulihan populasi gaharu alam. Tujuan penelitian ini adalah untuk memperoleh media elongasi yang optimal pada kultur in vitro gaharu dengan penambahan kombinasi zat pengatur tumbuh auksin dan sitokinin. Pada penelitian ini digunakan auksin IBA, serta sitokinin BAP dan Kinetin. Hasil penelitian elongasi diperoleh kombinasi auksin dan sitokinin terbaik yaitu, IBA 0,1 mg/L dan BAP 0,05 mg/L. Kombinasi ini meningkatkan tinggi dan jumlah ruas Aquilaria beccariana dengan tinggi rata-rata sebesar 1,64 cm dan jumlah ruas rata-rata sebesar 6,40 ruas. Pada kombinasi dan taraf ini diduga mekanisme kerja IBA dan BAP paling efektif dibanding perlakuan yang lain. Sedangkan kombinasi IBA 0 mg/L dan BAP 0,03 mg/L memberikan respon terbaik terhadap peningkatan jumlah tunas dengan rata-rata sebanyak 1,91 tunas.Kata Kunci: Aquilaria beccariana, tunas, elongasi, auksin, sitokinin

scholarly journals Diversity of mistletoes and their distribution in Dramaga Campus, West Java, Indonesia

2021 ◽  
Vol 948 (1) ◽  
pp. 012015
Author(s):  
S Wahyuningtias ◽  
A Mardiastuti ◽  
Y A Mulyani
Keyword(s):  
Tree Species ◽  
Field Research ◽  
Flowering Plants ◽  
Average Height ◽  
Complex Field ◽  
Tree Plantation ◽  
Averrhoa Carambola ◽  
Housing Complex ◽  
Samanea Saman ◽  
Trees And Shrubs

Abstract Mistletoes are flowering plants in the Santalales order that parasitize the branches of trees and shrubs. The objective of this research was to reveal the diversity of mistletoe species and record their distribution within this study site. The study site was Dramaga Campus (240 ha), which consisted of a mosaic of tree plantation, experimental fields, buildings, and a housing complex. Field research was conducted in February-March 2021 by censusing all mistletoes, their distribution, and plant species parasitized by the mistletoes. There were 351 individual mistletoes found, consisted of 5 species: Dendrophthtoepentandra (55.2%), Viscum ovalifolium (32.3%), Scurrula atropurpurea (9.1%), Macrosolen chochinchinensis (2.8%), and Viscum articulatum (0.6%). These mistletoes were found mostly on branches or twigs (99.1%) and few on trunks (0.9%) of 49 tree species (25 families) having an average height of 14.9±4.2m, and diameter 34.11± 22.22cm. Tree species frequently parasitized were Falcataria moluccana (32.8%), followed by Samanea saman (12.5%), and Averrhoa carambola (7.7%). Most mistletoes were found in the open area (99.1%), including on trees between/among buildings and along roads/streets, mainly on the south and southeast part of the campus. The mistletoe attacked in this research location was included in the low category (79.4%).

scholarly journals Sudden Oak Death Caused by Phytophthora ramorum in Oregon

Plant Disease ◽  
2002 ◽  
Vol 86 (4) ◽  
pp. 441-441 ◽  
Author(s):  
E. M. Goheen ◽  
E. M. Hansen ◽  
A. Kanaskie ◽  
M. G. McWilliams ◽  
N. Osterbauer ◽  
...  
Keyword(s):  
San Francisco ◽  
Aerial Survey ◽  
Selective Medium ◽  
Phytophthora Ramorum ◽  
Its Sequences ◽  
Sudden Oak Death ◽  
Usda Forest Service ◽  
Plant Materials ◽  
Solid Media ◽  
Lithocarpus Densiflorus

Sudden oak death, caused by Phytophthora ramorum (1,2), has been found for the first time in Oregon, killing tanoak, Lithocarpus densiflorus, trees. To our knowledge, this is the first report of the disease outside of the San Francisco to Monterey area in California, (300 km to the south). Nine areas of infestation, all within a 24-km2 area, were discovered on forest lands near Brookings, in southwest Oregon. Mortality centers ranged in size from 0.2 to 4.5 ha and included 5 to approximately 40 diseased trees. P. ramorum was isolated from stem cankers using Phytophthora-selective medium. Isolates had distinctive morphological features characteristic of P. ramorum, including abundant production of chlamydospores and caducous, semipapillate sporangia on solid media. Internal transcribed spacer (ITS) sequences of isolates of P. ramorum from Oregon were identical to ITS sequences of isolates from California (1). The pathogen also was isolated from necrotic lesions on leaves and stems of native Rhododendron macrophyllum and Vaccinium ovatum growing beneath diseased tanoaks. In July 2001, the disease was located by an aerial survey conducted cooperatively by the USDA Forest Service and Oregon Department of Forestry. All lands within 1.6 km (1 mile) of the mortality centers are subject to Oregon quarantine, which bars the transport of any host plant materials. An eradication effort is currently underway. Symptomatic plants and all known host plants within 15 to 30 m of symptomatic plants are being cut and burned in the first phase of this operation. The total treated area is approximately 16 ha. References: (1) D. M. Rizzo et al. Plant Dis. In press. (2) S. Werres et al. Mycol. Res. 105:1155, 2001.

scholarly journals Rapid and Efficient Plant Regeneration from Nodal Explants of Artemisia annua L.

2012 ◽  
Vol 22 (1) ◽  
pp. 33-39 ◽  
Author(s):  
B. Janarthanam ◽  
P. Rashmi ◽  
E. Sumathi
Keyword(s):  
Plant Regeneration ◽  
Growth Response ◽  
Artemisia Annua ◽  
Average Length ◽  
Shoot Elongation ◽  
Nodal Explants ◽  
Average Height ◽  
Farm Yard Manure ◽  
Artemisia Annua L ◽  
Half Strength

An efficient plant regeneration protocol was developed for Artemisia annua, an aromatic medicinal herb. Nodal explants inoculated on MS supplemented with 4.44 ?M BAP showed better growth response and produced 116.2 ± 0.1 micro-shoots of an average length 1.9 ± 0.3 cm after 35 days culture. The cluster of small shootlets were cultured on shoot elongation medium supplemented with 1.44 ?M GA3 and 10% coconut milk (CM) showed shoot elongation up to 4.6 ± 0.7 cm. Roots were induced after transfer to half strength MS supplemented with 2.46 ?M IBA produced 14.3 ± 0.2 roots with an average height of 4.3 ± 0.53 cm after 30 days. The rooted plantlets were transferred for hardening, 80 per cent of plantlets survived and resumed growth in the mixture of soil, vermiculite and farm yard manure (1 :  1 : 1). DOI: http://dx.doi.org/10.3329/ptcb.v22i1.11257 Plant Tissue Cult. & Biotech. 22(1): 33-39, 2012 (June)

scholarly journals First Report of Phytophthora ramorum on Rhododendron sp. in Spain

Plant Disease ◽  
2002 ◽  
Vol 86 (9) ◽  
pp. 1052-1052 ◽  
Author(s):  
E. Moralejo ◽  
S. Werres
Keyword(s):  
San Francisco ◽  
Mating Type ◽  
Free Water ◽  
Aerial Mycelium ◽  
Phytophthora Species ◽  
Phytophthora Ramorum ◽  
Research Centre ◽  
Biological Research ◽  
Fluorescent Light ◽  
First Report

Phytophthora ramorum has been recently described (4) from isolates collected since approximately 1993, from Rhododendron and Viburnum in the Netherlands and Germany. Since 2001 and 2002, respectively, there have been unconfirmed reports from Poland and Great Britain (1). There are growing concerns about this oomycete since it has been recognized as the causal agent of sudden oak death in California, where thousands of oaks and tanoaks (Quercus agrifolia, Q. kelloggii, Q. parvula var. shrevei, and Lithocarpus densiflorus) have died. Since the first outbreak in Marin County, California in 1995, (3) the epidemic has remained concentrated mainly along the Pacific Coast near San Francisco but has been reported in Oregon (2). There have been no reports of oaks or other trees affected in Europe. During February 2002, E. Moralejo surveyed several nurseries in Mallorca, (Balearic Islands, Spain) to verify the presence of P. ramorum on rhododendron. Two shipments of rhododendrons, from the towns of Palma and Santa Maria del Camí, showed twig blight and necrotic spots at leaf tips and margins. Less than 0.5% of the aerial parts of the potted plants of both sets were affected. Isolations from symptomatic tissue consistently yielded cultures of Phytophthora using selective media (corn meal agar supplemented with nystatin, rifampicin, and ampicillin). Pure cultures were obtained from three isolates by hyphal-tip transfers on carrot piece agar (CPA) and identified as P. ramorum on the basis of morphological and cultural characters (4). Colonies grown on CPA at 17°C were appressed with sparse aerial mycelium and formed typical concentric growth rings under 16 h fluorescent light. Cardinal temperatures for vegetative growth were 2°C (minimum), 20°C (optimum), and 28°C (maximum). Daily radial growth was 3 to 3.2 mm at 20°C. Sporangia formed singly or in clusters on aerial sporangiophores in the absence of free water, and were mainly semipapillate, caducous, with a very short or no pedicel, ellipsoidal to elongated-ovoid, with a length/breath ratio of 1.9 to 2.1. Large spherical, terminal, and intercalary chlamydospores, 32 to 72 μm in diameter, were readily formed in agar. The mating type of these isolates from Mallorca was A1 based on dual cultures on CPA with four different heterothallic Phytophthora species. Crossing was successful with P. cryptogea BBA 63651 mating type A2. Oogonia were subglobose and measured 24 to 32 μm in diameter. Oospores were plerotic. Antheridia were always amphigynous, and mainly barrel-shaped to spherical, 14 to 22 μm in diameter One of the three isolates also produced a very small number of gametangia with the A2 tester strain P. cinnamomi BBA 62660, but the oospores appeared degenerate. Only A1 mating type strains of P. ramorum have been found in Europe. The Mallorca isolates have been deposited in the culture collection of the Federal Biological Research Centre for Agriculture and Forestry (BBA), Germany. To our knowledge, this is the first report of P. ramorum in Spain. Further research is urgently needed to assess whether the Mediterranean evergreen oak ecosystem is in danger. References: (1) EPPO Reporting Service. Published on-line, http://www.eppo.org/PUBLICATIONS/EPPO_RS/reporting_service.html Publication no. 2002/040 and 2002/077. (2) E. M. Goheen et al. Plant Dis. 86:441, 2002. (3) D. M. Rizzo et al. Plant Dis. 86:205, 2002. (4) S. Werres et al. Mycol. Res. 105:1155, 2001.

First Report of Phytophthora ramorum Infecting Mistletoe in California

2011 ◽  
Vol 12 (1) ◽  
pp. 38 ◽  
Author(s):  
Kathleen L. Riley ◽  
Gary A. Chastagner
Keyword(s):  
Douglas Fir ◽  
Black Walnut ◽  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Christmas Tree ◽  
Tree Plantation ◽  
First Report ◽  
Plant Parts ◽  
White Fir ◽  
Zoospore Suspension

In 2005 and 2006, white fir and Douglas-fir growing in a Christmas tree plantation near Los Gatos, CA, under a black walnut tree infected with mistletoe tested positive for Phytophthora ramorum, the cause of Sudden Oak Death. Isolation from a symptomatic mistletoe inflorescence stalk was positive for P. ramorum. In 2007, fresh mistletoe leaves, stems, inflorescence stalks, and berries were inoculated with a zoospore suspension of the mistletoe isolate. All of the plant parts developed symptoms, and P. ramorum was isolated from each of them. This is the first report of an infection of a hemiparasite with P. ramorum. Accepted for publication 20 January 2011. Published 9 February 2011.

Pterocarpus macrocarpus (Burma padauk).

2021 ◽  
Author(s):  
Julissa Rojas-Sandoval
Keyword(s):  
Puerto Rico ◽  
Natural Regeneration ◽  
Average Height ◽  
Native Range ◽  
Sensitive Species ◽  
Northern Thailand ◽  
Volume Table ◽  
Open Forest ◽  
Disturbed Areas ◽  
Tall Tree

Abstract P. macrocarpus is a medium to large (usually up to 25 m tall, but sometimes up to 35 m tall) tree native to Myanmar, northern Thailand, Cambodia, Laos and Vietnam. It is a light-demanding, frost sensitive species, and natural regeneration is generally best in dry, open forest, and in disturbed areas. In its native range it grows best on sandy loams (Hundley, 1957). In Puerto Rico, it has grown well on soils ranging from sandy loams to well-drained clays (Francis, 1989). A volume table is available for a trial plantation in Laos; trees had attained an average height of 14.5 m after 13 years (Hjelm, 1995). Although small trees coppice well, coppicing ability declines with size.

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