Limited Evidence for Accumulation of Latent Infections of Canker-Causing Pathogens in Shoots of Stone Fruit and Nut Crops in California.

Prevalence of latent infections of the canker-causing fungi and species of , , , , and in young shoots of almond, prune, and walnut trees in California was studied to test the hypotheses that latent infections accumulate from current-season shoots to 1-year-old shoots in the orchard and there are distinct associations among pathogen taxa present as latent infections in the same shoot. Samples of newly emerged and 1-year-old shoots were periodically collected in each almond, prune, and walnut orchard for two growing seasons. A real-time quantitative PCR assay was used to quantify latent infection with three parameters: incidence, molecular severity, and latent infection index.

Inoculum quantification of canker-causing pathogens in prune and walnut orchards using real-time PCR.

Aims: A real-time quantitative PCR (qPCR) assay was established to quantify the inoculum densities in the air and rainwater for six canker-causing pathogen groups in prune and walnut orchards in California.

Methods And Results: The previously published DNA primers to target six pathogen groups including Botryosphaeria dothidea, Cytospora spp., Diplodia spp.

Understanding the Process of Latent Infection of Canker-Causing Pathogens in Stone Fruit and Nut Crops in California.

The Botryosphaeriaceae family is considered a fungal family that includes pathogens causing latent infection of woody plants, and a number of species were identified as causal pathogens of canker and shoot blight diseases. To better understand the process of latent infection of major canker-causing pathogens in woody tissues in different tree crops important in California, shoot and bud samples were randomly collected from four tree crops: almond, dried plum, pistachio, and walnut. The previously developed DNA primers and quantitative real-time PCR (qPCR) assay systems were applied to detect six canker-causing pathogen groups, including , and species of , , , , and The concepts of molecular severity (MS) and latent infection index (LII) were introduced and applied to quantify the latent infection levels for these samples.

Interaction Between and Causing Branch Dieback and Fruit Blight of English Walnut in California, and the Effect of Pruning Wounds on the Infection.

Botryosphaeriaceae and Diaporthaceae species are the causal agents of branch dieback of English walnut in California. In this study, the effects of the interaction between and were evaluated in vitro by using mycelial plugs or spore suspensions and in vivo by inoculating shoots and epicarps (hulls) of walnut. Single inoculations of each species and different coinfection treatments were performed under laboratory or field conditions.

Effects of Wound Size, Amount of Sap, and Number of Blighted Nuts on Infection of Pistachio Organs by Neofusicoccum mediterraneum.

Laboratory and field studies were conducted to determine the effects of wounding of nut exocarp, susceptibility period after wounding, and sap nut on infection of pistachio nut by Neofusicoccum mediterraneum, the main causal agent of panicle and shoot blight of pistachio. Under controlled conditions and in the field, detached nuts were inoculated with a conidial suspension 30 min before or after wounding. In addition, a 30-µl drop of pistachio sap was placed on the surface of noninjured nuts 30 min before or after they were wounded and then inoculated.

Development of qPCR systems to quantify shoot infections by canker-causing pathogens in stone fruits and nut crops.

Aims: To develop real-time PCR assays for quantification of shoot infection levels of canker disease of stone fruits and nut crops caused by six fungal pathogen groups.

Methods And Results: This study focused on six major canker-causing fungal pathogen groups: Phomopsis sp., Botryosphaeria dothidea, Lasiodiplodia sp.

A Single Center 11 Year Experience with 202 Pancreas Transplants in the New Millennium: Evolving Trends.

Unlabelled: Our single center experience with pancreas transplantation (PTx) over an 11+ year period is reviewed.

Methods: We retrospectively studied outcomes in 202 consecutive PTxs in 192 patients at our center. All patients received either rabbit anti-thymocyte globulin (rATG) or alemtuzumab (Alem) induction with tacrolimus/mycophenolate mofetil and tapered steroids or early withdrawal.

Evaluation of Two Disease Warning Systems for Botryosphaeria Panicle and Shoot Blight of California Pistachio and Efficient Control Based on Early-Season Sprays.

Two empirical models to predict infection events were evaluated for control of Botryosphaeria panicle and shoot blight, caused by a Fusicoccum sp., as well as the effectiveness of early-season fungicide sprays on the control of this disease of pistachio. A model incorporating wetness duration was superior to one based solely on duration of rains ≥1 mm/h for ≥4 h and with temperature ≥11°C.

Antagonism of Paenibacillus lentimorbus to Botryosphaeria dothidea and Biological Control of Panicle and Shoot Blight of Pistachio.

A potential microbial fungicide, Paenibacillus lentimorbus isolate CBCA-2, against Botryosphaeria dothidea, the pistachio panicle and shoot blight fungus, was obtained from healthy pistachio leaves by both in vitro and in vivo screening techniques. CBCA-2 caused 100% inhibition of pycnidiospore germination after 24 h incubation at 25°C. Malformation of pycnidiospores and hyphae, and lysis and swollen pycnidiospores of B.

First Report of Botryosphaeria rhodina Causing Shoot Blight of Pistachio in California.

In the summers of 2000 and 2001, shoot blight was observed in pistachios (Pistacia vera L.) grown in Kern County, California. Black, necrotic lesions developed at the base of shoots originating from contaminated or partially infected buds.

Dynamics and Pattern of Latent Infection Caused by Botryosphaeria dothidea on Pistachio Buds.

A study was conducted in four commercial pistachio orchards to monitor the presence and pattern of external contamination and latent infections of buds by Botryosphaeria dothidea between 1998 and 2000. Symptomless buds were sampled every 2 to 3 weeks and analyzed either by a washing/crushing method or by direct plating of split (half) or intact buds on lactic acid potato dextrose agar. The proportion of infected buds varied among orchards over time.

First Report of Aspergillus Vine Canker of Table Grapes Caused by Aspergillus niger.

A vine canker was first observed in the San Joaquin Valley, CA, in fall 1989, on exceptionally vigorous 1-year-old cv. Redglobe vines (Vitis vinifera) when vines were trained up the stakes. Since 1989, the same canker symptoms have been observed in Tulare, Kern, Fresno, and Riverside (Coachella Valley, CA) counties on cv.