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Survival of Fusarium circinatum in colonized pine needles and wood pieces was measured. Naturally colonized branches and their needles were cut into small pieces and placed in mesh bags on the soil surface at two locations in northern Spain. Pieces were recovered periodically, cultured on a selective medium, and microscopically examined to identify the species. After 507 days, F. circinatum was recovered from 0 to 27% of the wood pieces and from none of the needles. After 858 days, F. circinatum was not recovered from any wood pieces but was found to be present on 1 out of 220 needle pieces analysed. Artificially infested pieces of wood and needles were placed on 5-mm sieved soil either in plastic boxes at controlled temperature or in mesh bags under field conditions. No survival was recorded after 794 days under field conditions and the decline over time occurred more rapidly in inoculated pieces under field conditions. Soil was also infested with conidia of F. circinatum and survival was estimated. No conidia were recovered after 224 days at 30°C, although at 20 and 5°C the respective populations were 20 and 3700 cfu/g soil. Fusarium circinatum was not recovered from 2-mm-sieved soil collected under pitch canker-infected pines. Results indicate that branch segments and needles naturally colonized by F. circinatum will not be a potential source of inoculum, and the fungus in soil is not likely to contribute to reinfection of new plantations after 2 years.

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Cucumber, melon, watermelon, and zucchini are intensively cropped in the southern part of Spain where approximately 20,000 ha of the crops are grown in greenhouses. In the spring of 2007, zucchini plants (Cucurbita pepo) at the fruit-bearing stage in three commercial plastichouses in Almería exhibited necrosis on the basal stem, wilt, and death. The incidence of dead plants was 20 to 30%. Fusarium solani was consistently isolated from the basal stems of symptomatic plants on potato dextrose agar (PDA). Cultures of six single-hyphal transfers were identified on the basis of molecular sequences and morphological characteristics (2). Sequences of ribosomal DNA from ITS1 region, 5.8S rDNA, and ITS2 were identical for all six isolates of F. solani. The rDNA sequence of isolate Fscl-3 of F. solani was deposited as GenBank Accession No. AM940070. The pathogenicity of these six isolates of F. solani was tested in two experiments conducted in one plastichouse in Almería. Pregerminated seeds of zucchini cv. Consul were sown in 1-liter containers filled with vermiculite on 21 May and 22 June, 2007 (experiments 1 and 2, respectively). Plants at the one- to two-true-leaf stage or younger were inoculated with a soil drench of 2.0 to 8.4 × 105 propagules per ml). One colonized PDA petri plate of each isolate was blended and homogenized in 500 ml of distilled water. Inoculum (50 ml per plant) was poured around the stem of zucchini plants growing in vermiculite. The experimental design was a randomized complete block with three replicates with each plot comprising four plants (one plant per container). In both experiments, 12 uninoculated plants of the same cultivar served as controls. Plants were maintained for 1 month following inoculation in a greenhouse with mean temperatures ranging between 20.7 and 24.6°C and 23.3 to 29.8°C for experiments 1 and 2, respectively. Wilting first occurred 9 days after inoculation, and 14 days later, all plants inoculated with the F. solani isolates died. Inoculated plants exhibited lesions on the stem base without rot of secondary roots. At the end of the experiment, the uninoculated plants remained asymptomatic. Results of experiment 2, with higher temperatures, were similar. The pathogen was consistently recovered from symptomatic plants in both experiments, fulfilling Koch's postulates. Although F. solani f. sp. cucurbitae race 1 was reported in field squash (C. maxima) in the province of Valencia of east-central Spain (1), to our knowledge, this is the first report of F. solani as the causal agent of crown rot of zucchini plants in plastichouses in the Almería Province of Spain, one of the world's largest concentrations of greenhouses. References: (1) J. García-Jiménez et al. Plant Dis. 81:1216, 1997. (2) C. M. Messiaen and R. Cassini. Taxonomy of Fusarium. Page 427 in: Fusarium: Diseases, Biology, and Taxonomy. P. E. Nelson et al., eds. Pennsylvania State University, University Park, 1981.

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Fusarium circinatum, the causal agent of pitch canker disease on pines, can be disseminated by wood produced in infested areas. The purpose of the study was to evaluate the effect of wood preservatives, commonly used against sapstain and wood-decay fungi, on growth and sporulation of Fusarium circinatum. Seven active ingredients of antisapstain and antiwood-decay preservatives were evaluated by their inhibition of mycelial growth. Propiconazole, tebuconazole, and 3-iodo-2-propinyl butyl carbamate (IPBC) were effective against F. circinatum, whereas hydroxycarbonate of cooper was not. An assay was also conducted to evaluate the efficacy of three commercial antisapstain and two anti-wood-decay preservatives on Pinus radiata sapwood blocks that were previously inoculated with Fusarium circinatum. The product with the best efficacy was an antidecay preservative composed of tebuconazole, propiconazole, and dichlofluanid. None of the antisapstain preservatives tested was effective even though they contained fungicidal ingredients. Effects of dosage, product application, and formulation on the efficacy of these preservatives are discussed.Wood preservatives prevent dispersal of Fusarium circinatum Y. Serrano et al.

This study is to identifies the mosses that appear in disturbed sites of five forest reserves of the north coast limestone area of Puerto Rico. Thirty-three species in 26 genera were found. Five species show a wide distribution. The number of species found in disturbed sites of the forest reserves varies from 9 species at Tortuguero and Cambalache to 19 species at Guajataca. The families with the greatest number of species are Fissidentaceae (6 species)and Hypnaceae (5 species). Pleurocarpus species represent from 59 to 87% of this flora in the 5 areas.Sporophytes were observed in 14 (42.4%) species and in all the species found in 4 or more forest reserves.The north coast limestone area of Puerto Rico has been subjected to ecological degradation and today much of this area has been lost to urbanization.The remaining area is covered mainly by secondary vegetation; nevertheless, in addition to the forest reserves some sites serve as habitat for endemic, rare and endangered species (U.S. Fish and Wildlife Service 1987a, b, 1994).

In 2001 and 2002, bean plants ( Phaseolus vulgaris cvs Festival and Donna) cultivated on rockwool slabs in two commercial greenhouses in southeastern Spain were observed with root necrosis and necrotic streaks at the base of stems. In one greenhouse a few, scattered plants were affected, while in the other an estimated 20-30% dead plants occurred in distinct clusters. A Pythium sp. was consistently isolated from roots and stems of the affected plants on potato dextrose agar and cornmeal agar amended with pimaricin, ampicillin and rifampicin (P 5 ARP).Single hyphal transfers gave pure cultures of this oomycete. Four isolates from different plants produced filamentous inflated sporangia with zoospores and aplerotic oospores. Sequences of ribosomal DNA from ITS1 region, 5·8S rDNA and ITS2 were identical for all four isolates and that from isolate Py-V3 has been deposited as GenBank Accession No. AM396958. The isolates were identified as P . myriotylum on the basis of molecular sequences and morphological characteristics (Van der PlaatsNiterink, 1981).Phaseolus vulgaris cv. Emerite at the 5-7 leaf stage was inoculated with three isolates (Py-V1, 2 and 3) by irrigating plants with 50 mL of mycelial suspension, per plant, obtained by growing isolates on potato carrot agar (PCA) in 9 cm Petri dishes until they fully covered the surface, then blending and homogenizing mycelium in 300 mL sterile distilled water.The plants were grown in plastic bags filled with perlite and kept in a greenhouse where temperatures varied from 22-31 ° C. After 29 days all plants had necrotic roots, some with stem streaks and some eventually died, similar to the disease development originally observed. Control plants irrigated with sterile distilled water washed-off uninoculated PCA remained healthy. When inoculations were repeated at a lower temperature range (13-30 ° C), isolates Py-290 and Py-V2 caused root necrosis in all inoculated plants but stem streaks and death in only a few. Pythium myriotylum was reisolated from inoculated plants. High temperatures are associated with more severe disease development (Gay, 1969). This is the first report of P . myriotylum as the causal agent of root and stem necrosis of adult bean plants in Spain. References Bioforsk -Norwegian Institute for Agricultural and Environmental Research, Høgskoleveien 7,1432 Ås, NorwayIn 2004 and 2005, several soil surveys were conducted in the main melon ( Cucumis melo ) production areas of Honduras and Guatemala, all areas with a history of vine decline. Fifty-nine samples from twenty different farms were collected from the rhizosphere zone of wilted plants. Samples were analyzed by a baiting method consisting of sowing melon seeds in a mixture of each rhizosphere sample and vermiculite (1:6 vol/vol). Thirty-six melon plants per sample were placed in a growth chamber with a 16-h photoperiod and temperatures of 23 to 25 ° C. Diseased plants started to appear when plants showed one or two true leaves. The first symptom observed was girdling of the lower stem, followed by...