In September 2016, a survey conducted in the Circeo National Park revealed an outbreak and serious damage caused by the black twig borer (Xylosandrus compactus) and its associated fungi in the Mediterranean maquis. Among the affected hosts, Quercus ilex, Viburnum tinus, Ruscus aculeatus, Pistacia lentiscus, Laurus nobilis and Ceratonia siliqua, showed flagging and wilting of branches and, in younger individuals, the death of the whole plant occurred. In total, 18 different fungal taxa were found associated with the insect. These included Ambrosiella xylebori, Geosmithia pallida, Fusarium spp., Epicoccum nigrum and Bionectria sp. This is the first report in Europe of X. compactus and associated ambrosia fungi in a natural environment.

In 1995, severe symptoms were observed on ‘Caturra’ and ‘Catuaí’ coffee (Coffea arabica L.) varieties in farms in the southern part of the Central Valley in Costa Rica. Symptoms were reduced leaf size, malformation of leaves, curling of leaf edges, shortening of internodes, and severe leaf chlorotic mosaic, which sometimes became necrotic. Abortion of flowers and young beans was also observed, with a reduction in yield. Plants also showed irregular growth with an atypical curling appearance that gave rise to the Spanish name “crespera.” Ten and three healthy plants were inoculated by grafting in the greenhouse, using infected and healthy budwoods, respectively. Approximately 6 months after inoculation, 3 of 10 grafted plants with infected budwoods showed symptoms of leaf chlorosis, curling, and malformation of leaves and bunched new flushes. Samples of 39 symptomatic plants collected from the field and samples of 3 healthy plants maintained in the greenhouse were tested by enzyme-linked immunosorbent assay (ELISA). All (100%) analyzed symptomatic samples were positive for X. fastidiosa, and all healthy controls were negative. The symptoms observed in Costa Rica are different from those described for coffee leaf scorch in Brazil (1,2), but the climatological conditions and soil type present in Costa Rica are also very different from the areas where X. fastidiosa occurs in Brazil. Leafhoppers were collected randomly in one of the most affected regions. Graphocephala permagna and Erythrogonia sonora were the most frequent insect species found associated with coffee. In ELISA, 34.5% (10 of 29) and 23.8% (5 of 21) of the collected specimens belonging to G. permagna and E. sonora, respectively, tested positive for X. fastidiosa. These positive ELISAs do not necessarily mean that the insect is a vector. The results presented here extend the known geographic distribution of X. fastidiosa. To our knowledge, this is the first report of X. fastidiosa in coffee in Costa Rica. References: (1) M. J. G. Beretta et al. Plant Dis. 80:821, 1996. (2) de Lima et al. Plant Dis. 82:94, 1998.

Coffee plants exhibiting a range of symptoms including mild to severe curling of leaf margins, chlorosis and deformation of leaves, stunting of plants, shortening of internodes, and dieback of branches have been reported since 1995 in several regions of Costa Rica's Central Valley. The symptoms are referred to by coffee producers in Costa Rica as "crespera" disease and have been associated with the presence of the bacterium Xylella fastidiosa. Coffee plants determined to be infected by the bacterium by enzyme linked immunosorbent assay (ELISA), were used for both transmission electron microscopy (TEM) and for isolation of the bacterium in PW broth or agar. Petioles examined by TEM contained rod-shaped bacteria inside the xylem vessels. The bacteria measured 0.3 to 0.5 microm in width and 1.5 to 3.0 microm in length, and had rippled cell walls 10 to 40 nm in thickness, typical of X. fastidiosa. Small, circular, dome-shaped colonies were observed 7 to 26 days after plating of plant extracts on PW agar. The colonies were comprised of Gram-negative rods of variable length and a characteristic slight longitudinal bending. TEM of the isolated bacteria showed characteristic rippled cell walls, similar to those observed in plant tissue. ELISA and PCR with specific primer pairs 272-l-int/272-2-int and RST31/RST33 confirmed the identity of the isolated bacteria as X. fastidiosa. RFLP analysis of the amplification products revealed diversity within X. fastidiosa strains from Costa Rica and suggest closer genetic proximity to strains from the United States of America than to other coffee or citrus strains from Brazil.

Citrus variegated chlorosis (CVC) is an important disease mainly of sweet orange (Citrus sinensis (L.) Osbeck) cultivars. It was first described in Brazil in the state of Sā Paulo in 1987 (4). The disease has spread to all Brazilian states that grow citrus and is affecting more than one-third of the orange trees grown in Brazil. CVC is caused by Xylella fastidiousa, a xylem-limited, gram-negative bacterium. During the last 4 years, symptoms including leaf interveinal chlorosis, stunting, canopy dieback, and hard and undersized fruits, similar to those caused by CVC (3), appeared in sweet orange trees used as shade plants for coffee plantations and as fence posts in Costa Rica. Necrotic lesions on the abaxial side of the leaves as reported in Brazil were rarely observed. Leaf petiole samples from 25 symptomatic sweet orange trees reacted positively with a X fastidiosa-specific antiserum (AGDIA Inc., Elkart, IN) in a double-sandwich antibody enzyme-linked immunosorbent assay (DAS-ELISA). A fastidious, gram-negative bacterium identified as X. fastidiosa using DAS-ELISA was isolated on perwinkle wilt (PW) medium plates (1) from citrus stems showing CVC symptoms, but not from asymptomatic trees. The isolated colonies were circular and opalescent with diameters of 2 to 3 mm and were clearly visible within 6 to 7 days after streaking. Petiole sections from symptomatic plants observed with scanning electron microscopy showed rod-shaped bacteria with rippled cell walls tightly packed in xylem vessels, as described for X. fastidiosa previously (2), and with transmission electron microscopy, the bacteria were morphologically similar to those reported previously for CVC (2). To our knowledge, this is the first report of X. fastidiosa associated with citrus in Costa Rica. References: (1) M. J. Davis et al. Curr. Microbiol. 6:309, 1981. (2) J. S. Hartung et al. Phytopathology 84:591, 1994. (3) R. F. Lee et al. Summa Phytopathol. 19:123, 1993. (4) V. Rossetti et al. 1990, C.R. Acad. Sci. (Paris) 310:345–349.

Summary In two experiments (E1 and E2), 2909 and 1514 calves were produced by artificial insemination of zebu cows on two ranches in the Venezuelan floodplains. Semen of progeny‐tested national Brahman (B) bulls were used to produce the two control groups and of Charolais (C), Limousin (L), Marchigiana (M), Romosinuano (Criollo, R) and Simmental (S) in E1 and Angus (A), Chianina (K), Gelbvieh (G), L and S in E2 to produce F1 progeny. Calves were raised with their dams on savanna until weaning and on savanna, and improved pasture after this until 18 months. Birth weight (BW), weaning weight (WW) and 18‐month weight (18MW) were analysed by least‐squares procedures; breed group, sex, year and month of birth, age of dam, sire within breed, and breed × sex and year × month were included in the model. Breed group had highly significant effects on all weights. Adjusted means for BW, WW and 18MW (548 days) were 29.8 ± 0.2, 165.3 ± 1.1 (age 198 days) and 268.7 ± 1.9 kg in E1 and 31.7 ± 0.2, 205.9 ±1.2 (age 282 days) and 282.3 ± 1.3 kg in E2. The overall mean and range of group means for crossbred advantage for the three weights in E1 were: 2.5 (− 6.8‐7.7) %, 8.4 (3.9‐11.7) % and 10.9 (7.6‐16.4) % in E1 and; 6.7 (3.5‐10.2) %, 11.3 (9.9‐14.3) % and 11.9 (10.7‐14.2) % in E2. F1 C in E1 S and F1 S in E2 were superior to all other F1 groups in WW and 18MW. Breed × sex interaction was significant for BW and 18MW and crossbred advantage was higher in females than in males. Male superiority over females was highly variable beetween the breed groups. The highest significant difference between progeny of bulls with extreme genetic values within breeds was 14.7% for BW, 15.1% for WW and 16.8% for 18MW. Zusammenfassung Wachstum von F1 Bos taurus × Bos indicus versus Bos indicus Fleischrindern in Venezuela. I. Geburtsgewicht, Absatzgewicht und 18 Monate Gewicht In zwei Versuchen (E1 und E2) wurden in zwei Herden im venezolanischen Tiefland (Überschwemmungsgebiet) durch künstliche Besamung von Zebukühen 2909 und 1514 Kälber geboren. Mit Sperma von nachkommengeprüften venezolanischen Brahman (B) Bullen wurden zwei Kontrollgruppen gebildet und mit Charolais (C), Limousin (L), Marchigiana (M), Romosinuano (Criollo, R) und Simmental (S) Sperma (E1) und mit Angus (A), Chianina (K), Gelbvieh (G), L und S Sperma (E2) F1 Nachkommen produziert. Die Kälber wurden bis zum Absetzen zusammen mit ihren Müttern auf Savanne gehalten und danach bis zum Alter von 18 Monaten auf Savanne und verbesserter Weide. Die varianzanalytische Berechnung der Geburts‐ (GG), Absatz‐ (AG) and 18 Monate (18MG) Gewichte wurde mit der Methode der kleinsten Quadrate durchgeführt, unter Berücksichtigung der folgenden Effekte: Rassegruppe, Geschlecht, Geburtsjahr und — monat, Alter der Mutter, Vater innerhalb der Zuchtgruppe, Rassegruppe × Geschlecht und Jahr × Monat. Rassegruppe hatte einen hoch significanten Einfluss auf alle Gewichte. Die korrigierten Mittelwerte für GG, AG und 18MG (548 Tage) waren in E1 29,8 ± 0,2,165,3 ± 1,1 (Alter 198 Tage) und 268,7 ± 1,9 kg und in ...

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AntLCD4 antibody (T4)-coated microspheres were used to label CD4 cells in whole blood. The mixture was lysed and analyzed by a modified Coulter VCS hematology analyzer, which differentiated microspherelabeled cells by a change in Coulter volume, conductance, and light scatter. %CD3+/CD4+ fluorescent values from a profile were compared to %CD4 values using the VCS-microsphere method. CD3 gating was used to exclude CD4+ monocytes from the SOLS-FALS lymphocyte gate. The results correlated well (R = 0.996). The percentage of CD4+ lymphocytes from profile scatterplots and VCS scatterplots showed a line of regression close to the equivalence line (n = 76, slope = 0.96) when CD3 gating was used for the profile. These results suggest that CD3 gating, though necessary for SOLS-FALS scatterplots, may not be necessary for volume-conductance-light scatterplots. o 1995 Wiley-Liss, Inc.

Coffee ringspot virus (CoRSV) (family Rhabdoviridae) is transmitted by Brevipalpus phoenicis (Geijskes) (Acari: Tenuipalpidae). Coffee ringspot disease was first reported in coffee plants from Brazil in 1939 (1). In August 2000, severe symptoms of concentric ringspots and “oak leaf” patterns on coffee leaves (Coffea arabica L. cv. Catuai) were observed during field inspections conducted in two areas of San Gabriel de Desamparados, Costa Rica. The disease caused premature fruit and leaf drop in the affected plants. Some areas within the ringspot lesions remained green on senescent leaves. Because CoRSV particles remain restricted to lesion areas (1), this virus has not been purified, and antiserum for virus detection is not available. Therefore, leaves with symptoms were collected and examined by transmission electron microscopy. In ultrathin sections of symptomatic leaves, arrays of rhabdovirus-like particles were associated with the nucleus as described for CoRSV (2). Healthy tissues did not contain similar arrays of bacilliform and bullet-shaped particles. Twenty mites collected from the infected plants at the same locations and time were slide-mounted and identified as B. phoenicis. High populations of this mite were also observed infesting plants of Cajanus cajan L. that were intercropped with coffee at the same location. Sweet orange trees growing in the same fields as shade for the coffee did not show symptoms of citrus leprosis, a disease caused by another Brevipalpus-transmitted virus that was recently reported in Panama (3). To our knowledge, this is the first report of a virus similar to CoRSV in Costa Rica. The spread of this virus, presumably CoRSV, could seriously affect the coffee industry throughout Central America by increasing production costs. It may be necessary to apply one or more foliar acaricides to effectively control the mite vector. References: (1) A. Bitancourt. O. Biol. 5:33, 1939. (2) C. M. Chagas et al. Phytopathol. Z. 102:100, 1981. (3) F. S. Dominguez et al. Plant Dis. 85:228, 2001.