Efficiency of a non-recycling postharvest fungicide drencher to enhance management of apple decay and food safety.

Introduction: Recycling drenchers used to apply postharvest fungicides in pome fruit may spread microorganisms, i.e., plant and foodborne pathogens, that increase fruit loss and impact food safety.

Rating pome fruit quality traits using deep learning and image processing.

Quality assessment of pome fruits (i.e. apples and pears) is used not only for determining the optimal harvest time but also for the progression of fruit-quality attributes during storage.

A Haplotype-resolved, Chromosome-scale Genome for Malus domestica Borkh. 'WA 38'.

Genome sequencing for agriculturally important Rosaceous crops has made rapid progress both in completeness and annotation quality. Whole genome sequence and annotation gives breeders, researchers, and growers information about cultivar specific traits such as fruit quality and disease resistance, and informs strategies to enhance postharvest storage. Here we present a haplotype-phased, chromosomal level genome of Malus domestica, 'WA 38', a new apple cultivar released to market in 2017 as Cosmic Crisp®.

Is calcium deficiency the real cause of bitter pit? A review.

Bitter pit is a disorder affecting the appearance of apples. Susceptibility is genetically controlled by both the cultivar and rootstock, with both environmental and horticultural factors affecting its severity and proportional incidence. Symptoms appear more frequently at the calyx end of the fruit and consist of circular necrotic spots, which take on a "corky" appearance visible through the peel.

Effect of Rootstock Genotype and Arbuscular Mycorrhizal Fungal (AMF) Species on Early Colonization of Apple.

The effect of plant cultivar on the degree of mycorrhization and the benefits mediated by arbuscular mycorrhizal fungi (AMF) have been documented in many crops. In apple, a wide variety of rootstocks are commercially available; however, it is not clear whether some rootstock genotypes are more susceptible to mycorrhization than others and/or whether AMF species identity influences rootstock compatibility. This study addresses these questions by directly testing the ability/efficacy of four different AMF species (, , or ) to colonize a variety of commercially available Geneva apple rootstock genotypes (G.

Warmer autumns and winters could reduce honey bee overwintering survival with potential risks for pollination services.

Honey bees and other pollinators are critical for food production and nutritional security but face multiple survival challenges. The effect of climate change on honey bee colony losses is only recently being explored. While correlations between higher winter temperatures and greater colony losses have been noted, the impacts of warmer autumn and winter temperatures on colony population dynamics and age structure as an underlying cause of reduced colony survival have not been examined.

Using stink bug migration behavior for physical exclusion.

Stink bugs have become an increasing concern for tree fruit growers due to changing management strategies and the introduction of an invasive species. The use of broad-spectrum insecticides for stink bug control disrupts biological control and leads to secondary pest outbreaks. To seek alternative tactics, we investigated the physical exclusion of native stink bugs with single-wall net barriers at orchard borders.

Rootstock effects on leaf function and isotope composition in apple occurred on both scion grafted and ungrafted rootstocks under hydroponic conditions.

Rootstocks are used in modern apple production to increase productivity, abiotic and biotic stress tolerance, and fruit quality. While dwarfing for apple rootstocks has been well characterized, the physiological mechanisms controlling dwarfing have not. Previous research has reported rootstock effects on scion water relations.

Turning a Pest into a Natural Enemy: Removing Earwigs from Stone Fruit and Releasing Them in Pome Fruit Enhances Pest Control.

The European earwig (L.) (Dermaptera: Forficulidae) is an omnivorous insect that is considered a minor pest of stone fruit and a key predator of pests in pome fruit orchards. In many pome fruit orchards, earwigs are absent or in low abundance due to broad-spectrum spray programs and the slow recolonization rate of earwigs.

Rootstock and Crop Load Effects on 'Honeycrisp' Photosynthetic Performance and Carbohydrate Accumulation.

Rootstock selection and crop load adjustment are key practices in apple orchard management; nevertheless, the effects of rootstocks and crop load levels on important physiological processes of the scions, such as photosynthetic performance and carbohydrate accumulation, are still unclear. To investigate the impact of different rootstocks and crop load levels on scion photosynthesis and carbohydrate buildup, in 2020, 'Honeycrisp' trees grafted on rootstocks 'G.41', 'G.

Culture age of Tulasnella affects symbiotic germination of the critically endangered Wyong sun orchid Thelymitra adorata (Orchidaceae).

Orchids (Orchidaceae) are dependent on mycorrhizal fungi for germination and to a varying extent as adult plants. We isolated fungi from wild plants of the critically endangered terrestrial orchid Thelymitra adorata and identified them using a multi-region barcoding approach as two undescribed Tulasnella species, one in each of phylogenetic group II and III (OTU1) of the Tulasnellaceae. Using symbiotic propagation methods, we investigated the role of Tulasnella identity (species and isolate) and age post isolation, on the fungus's ability and efficacy in germinating T.

Seasonal activity of Trechnites insidiosus (Hymenoptera: Encyrtidae) and its host Cacopsylla pyricola (Hemiptera: Psyllidae) in pear.

Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae) is the most expensive and challenging insect pest of commercial pear trees in the Pacific Northwest. Integrated pest management (IPM) programs are working toward relying more heavily on natural enemies to reduce insecticide use. Trechnites insidiosus (Crawford) (Hymenoptera: Encyrtidae) is the main parasitoid of C.

Suitability of the shrub-steppe habitat of Eastern Washington for Halyomorpha halys (Hemiptera: Pentatomidae).

The invasive brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), has spread throughout most of Washington (WA) State since its detection in 2012. While it has emerged as a major agricultural and nuisance pest in the Pacific Northwest (PNW) west of the Cascade Mountains, pest pressure in the major tree fruit-growing areas in semi-arid northern and central WA State remains low. The reasons for this are unclear, although both biotic and abiotic conditions may be contributing factors.

Combining thermal imaging and soil water content sensors to assess tree water status in pear trees.

Volumetric soil water content is commonly used for irrigation management in fruit trees. By integrating direct information on tree water status into measurements of soil water content, we can improve detection of water stress and irrigation scheduling. Thermal-based indicators can be an alternative to traditional measurements of midday stem water potential and stomatal conductance for irrigation management of pear trees ( L.

Pear psylla and natural enemy thresholds for successful integrated pest management in pears.

Pear psylla, Cacopsylla pyricola (Förster), is the most economically challenging pest of commercial pears in Washington and Oregon, the top producers of pears in the United States. The objective of this study was to quantify economic injury levels and thresholds for pear psylla. We used the relationship between pear psylla adult and nymph densities, and fruit downgraded due to psylla honeydew marking to identify injury levels.

Transcriptomic approach to uncover dynamic events in the development of mid-season sunburn in apple fruit.

Apples grown in high heat, high light, and low humidity environments are at risk for sun injury disorders like sunburn and associated crop losses. Understanding the physiological and molecular mechanisms underlying sunburn will support improvement of mitigation strategies and breeding for more resilient varieties. Numerous studies have highlighted key biochemical processes involved in sun injury, such as the phenylpropanoid and reactive oxygen species (ROS) pathways, demonstrating both enzyme activities and expression of related genes in response to sunburn conditions.

The infection efficacy of Metarhizium strains (Hypocreales: Clavicipitaceae) against the Queensland fruit fly Bactrocera tryoni (Diptera: Tephritidae).

The Queensland fruit fly (Qfly), Bactrocera tryoni Froggatt, is a devastating pest of Australia's commercial fruit systems. Fruit fly mitigation is heavily centered around the use chemical insecticides, with limited investigation into microbial control alternatives. The wet tropics of northern Queensland is a highly biodiverse ecosystem containing many species of insect pathogenic fungi, but it is unclear whether any of these entomopathogens could contribute to Qfly management programs.

Bacterial Endosymbionts Identified From Leafhopper (Hemiptera: Cicadellidae) Vectors of Phytoplasmas.

Insects often harbor bacterial endosymbionts that provide them with nutritional benefit or with protection against natural enemies, plant defenses, insecticides, and abiotic stresses. Certain endosymbionts may also alter acquisition and transmission of plant pathogens by insect vectors. We identified bacterial endosymbionts from four leafhopper vectors (Hemiptera: Cicadellidae) of 'Candidatus Phytoplasma' species by direct sequencing 16S rDNA and confirmed endosymbiont presence and identity by species-specific conventional PCR.

Strong phylogenetic congruence between Tulasnella fungi and their associated Drakaeinae orchids.

The study of congruency between phylogenies of interacting species can provide a powerful approach for understanding the evolutionary history of symbiotic associations. Orchid mycorrhizal fungi can survive independently of orchids making cospeciation unlikely, leading us to predict that any congruence would arise from host-switches to closely related fungal species. The Australasian orchid subtribe Drakaeinae is an iconic group of sexually deceptive orchids that consists of approximately 66 species.

Evaluating invasion risk and population dynamics of the brown marmorated stink bug across the contiguous United States.

Background: Invasive species threaten the productivity and stability of natural and managed ecosystems. Predicting the spread of invaders, which can aid in early mitigation efforts, is a major challenge, especially in the face of climate change. While ecological niche models are effective tools to assess habitat suitability for invaders, such models have rarely been created for invasive pest species with rapidly expanding ranges.

Integrated Pest Management Programs for Pear Psylla, Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae), Using Kaolin Clay and Reflective Plastic Mulch.

Pear psylla, Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae), is the most economically important pest of pears grown in Washington State. Standard conventional management programs involve season-long broad-spectrum insecticide sprays. Although the industry uses some tools that are not disruptive to biological control, such as kaolin clay and selective insecticides, they are additions to broad-spectrum insecticides instead of replacements.

Environmental drivers of the occurrence and abundance of the Irukandji jellyfish (Carukia barnesi).

Understanding the links between species and their environment is critical for species management. This is particularly true for organisms of medical and/or economic significance. The 'Irukandji' jellyfish (Carukia barnesi) is well known for its small size, cryptic nature, and highly venomous sting.