Identification of and in citrus packinghouses in California, their sensitivity to cyproconazole, and incomplete cross-resistance to propiconazole.

High levels of sour rot on propiconazole-treated lemon fruit that were stored for extended times in some California packinghouses in 2020 and 2021 initiated surveys on fungicide sensitivity of the causal pathogen. In isolations from diseased fruit in 2020 to 2023, 157 isolates of Geotrichum spp. were obtained.

Phylogenomic analyses and comparative genomics of Pseudomonas syringae associated with almond (Prunus dulcis) in California.

We sequenced and comprehensively analysed the genomic architecture of 98 fluorescent pseudomonads isolated from different symptomatic and asymptomatic tissues of almond and a few other Prunus spp. Phylogenomic analyses, genome mining, field pathogenicity tests, and in vitro ice nucleation and antibiotic sensitivity tests were integrated to improve knowledge of the biology and management of bacterial blast and bacterial canker of almond. We identified Pseudomonas syringae pv.

Regional Comparisons of Sensitivities of and Causing Citrus Brown Rot in California to Four New and Two Older Fungicides.

Isolates of the citrus brown rot pathogens and from the Inland Empire (IE) and Ventura Co. (VE) regions of southern California were evaluated for their sensitivity to ethaboxam, fluopicolide, mandipropamid, and oxathiapiprolin, and the previously published baselines that were generated for Central Valley (CV) isolates of California were expanded. Fungicides were generally more toxic to CV isolates of both species for all four fungicides.

Diversity and Clonality in Populations of and Causing Brown Rot of Citrus in California.

and are currently the primary causal organisms of brown rot of citrus fruits in California. To possibly find an explanation for the prevalence of the previously minor species , we determined the population structures of both pathogens in California using next-generation sequencing and population genomics analyses. Whole-genome sequencing and aligning with newly assembled reference genomes identified 972,266 variants in 132 isolates of and 422,208 variants in 154 isolates (including 24 from noncitrus tree crops) of originating from three major growing regions.

Interactive effect of branch source-sink ratio and leaf aging on photosynthesis in pistachio.

Tree source-sink ratio has a predominant and complex impact on tree performance and can affect multiple physiological processes including vegetative and reproductive growth, water and nutrient use, photosynthesis, and productivity. In this study, we manipulated the branch level source-sink ratio by reduction of photosynthetic activity (partial branch defoliation) or thinning branch fruit load early in the growing season (after fruit set) in pistachio () trees. We then characterized the leaf photosynthetic light response curves through leaf aging.