Location: Innovative Fruit Production, Improvement, and Protection
Project Number: 8080-21000-032-061-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Aug 1, 2024
End Date: May 31, 2026
Objective:
The objectives for this proposal are to: 1) Monitor canopy microclimatic conditions, insect presence on trees, and insect-caused fruit damage of apple cultivars during the growing season; 2) Assess fruit injury caused by insect pests and quality traits of apple cultivars at harvest; and 3) Determine apple cultivar-specific and cross-cultivar relationships among canopy conditions, fruit quality traits, and insect prevalence.
Approach:
ARS will evaluate commonly grown apple cultivars in two commercial orchards in Maryland. For each cultivar, 10 trees bordering the cultivar and 10 trees in the interior will be randomly selected. Data loggers with built-in sensors will be placed inside the canopy to record ambient temperature and relative humidity. Canopy leaf area index and light interception will be measured to estimate canopy density and light environments, along with visual inspection of rosy and woolly apple aphids on trees and fruit damage caused by plum curculio (PC) in early season (late May) and mid-season (early July past physiological June drop of fruitlets). At harvest, 400 fruit on 20 trees (20 fruit/tree) per cultivar will be collected. Half of the fruit will be assessed for damage caused by PC, brown marmorated stink bug (BMSB), codling moth (CM), oriental fruit moth (OFM), and San Jose scale (SJS). The other half of collected fruit will be determined for quality traits, including size, color, firmness, starch content, soluble solids concentration, and acidity. Data will be compared among apple cultivars located in the same orchard using one-way ANOVA with Tukey’s HSD and non-parametric tests. Pearson’s correlation and linear regression will be performed with all parameters to determine the relationships among canopy conditions, fruit traits, and presence of and likelihood of fruit injury caused by each insect pest surveyed in this research across apple cultivars.
