ASHS 2024 Conference

Over the past decade, the cultivation of olive trees (Olea europaea) in Florida has experienced remarkable growth, expanding tenfold. Currently, there are more than 60 growers tending to approximately 800 acres spread across 26 counties in Florida. Despite this significant expansion in Florida’s olive tree cultivation, accompanied by a surge in global olive oil demand, research in this area has been lacking. To address this gap, comprehensive data collection commenced in the summer of 2023 through three distinct trials located in Jay, Wauchula, and Fort Pierce, Florida. These trials aim to determine the most productive olive tree varieties and optimal cultivation techniques tailored to Florida’s diverse climate and soil compositions. Given variations in grove management approaches and tree maturity levels, a range of cultivars representing different genotypes were being tested across various locations. The cultivar ‘Arbequina’ was consistent across all trials. In addition to ‘Arbequina’, other cultivars such as ‘Koroneiki’ and ‘Sikitita’ were assessed in Wauchula, while ‘Lecciana’ and ‘Sikitita’ were examined in Fort Pierce. Throughout the trials, parameters including soil fertility, temperature, soil moisture levels, as well as leaf nutrient status and phenological observations were quantified twice a year. No nutrient deficiencies were detected in either soil or leaf samples, but also no consistent patterns regarding flowering or production were observed. The ongoing data collection is expected to shed light on critical aspects regarding the feasibility of olive tree cultivation within the Florida environment and provide valuable insights for growers and stakeholders.

Haskap (Lonicera caerulea L.), also known as edible blue honeysuckle or honeyberry, is a new and emerging berry crop in North America. Its resilience to cold temperatures, adaptability to various soil pH levels, distinctive flavor, and health benefits make it suitable for cultivation in colder climates. The period from flowering to fruit ripeness is remarkably brief in haskap, typically ranging from six to eight weeks, offering an advantageous alternative in shorter-growing regions. Yet, detailed guidance on its cultivation and fruit quality is scarce. To aid growers, a two-year study at the Western Agricultural Research Center assessed the ripening timelines of 15 haskap varieties, providing critical data to optimize harvest timing and management practices. Throughout the growing seasons of 2022 and 2023, from May through August, fruit quality and ripening stages were closely monitored two to three times a week by collecting berry samples. From these samples, traits such as total soluble solids content (Brix), pH, total acidity (TA), single berry mass, and berry color changes were measured. Assessment of this phenotypic data revealed distinct patterns for each trait across the different varieties studied. Cultivars such as 'Blue Goose', 'Boreal Beauty', and 'Sugar Mountain Blue' reached their harvest readiness sooner, around approximately 650 growing degree days (GDD) for the year, followed by a reduction in berry size due to water loss and a rise in sugar concentration. In contrast, Aurora, Tana, and Kawai matured more slowly, achieving peak ripeness near ~1000 GDD. Yet, they preserved their mature fruit characteristics (consistent berry weight and sugar levels) through the sampling period’s end. These insights into the ripening patterns of haskap varieties from prominent breeding programs in North America can inform growers as they choose specific cultivars and decide on optimal harvest times.

Botrytis fruit rot (BFR) or grey mold disease, caused by Botrytis cinerea Pers., poses a significant threat to strawberry crop production in the mid-Atlantic region of the U.S. The extensive use of fungicides to combat this fungal disease has resulted in listing the strawberries in the Dirty Dozen fruits and the evolution of fungal strain resistance to fungicides. Hence, exploring potential alternative strategies is crucial to reducing pesticide use and minimizing BFR; as such, utilizing resistant plant cultivars is a potential strategy. With this, the current study aimed to assess the susceptibility of two cultivars to Botrytis, Flavorfest, and Honeoye, which showed resistance to gray mold under in vitro conditions, and compare them with grower standard cultivars, Chandler and Sweet Charlie, under field conditions. The field evaluations were conducted at two locations during the 2022-2023 growing season: Hampton Roads Agriculture Research and Extension Center in Virginia Beach, VA, and a grower farm in Fredericksburg, VA. Transplanting of plants was done on October 12, 2022, in Fredericksburg and October 17, 2022, in Virginia Beach. A randomized complete block design was used in the experiments with four replicates per cultivar in Virginia Beach and three replicates in Fredericksburg, and each replicate had 12 plants. Fruits were harvested twice a week throughout the season to assess BFR occurrence and marketable crop yield. The main effect of the cultivar was significant for Botrytis fruit rot and marketable yield for the season. 'Honeoye' showed the lowest BFR-infested fruits (~6.5 g of fruits/plant), compared to 'Chandler' (22.5 g). However, 'Chandler' showed the highest marketable yield (713 g/plant), followed by 'Sweet Charlie' (473 g), while 'Flavorfest' (261 g) and 'Honeoye' (216 g) produced the lowest yields. Additionally, marketable yield differed by location, with higher yields recorded in Virginia Beach. Post harvest parameters including fruit firmness, total soluble solids (TSS), and pH that were measured on a subsample of fruits in Virginia Beach showed significant cultivar effect . ‘Honeoye’ had the least firm fruit but had the highest TSS for the season, not different than ‘Sweet Charlie’. The fruit pH of ‘Sweet Charlie’ was the highest. Information on resistant cultivars could assist growers in choosing appropriate cultivars to meet their farm production practices.

Blackcurrant (Ribes nigrum L.) is a small fruit known for its health benefits, but treatment effects on postharvest storage for fresh markets remains understudied compared to other berries, such as blueberry (Vaccinium spp.). This work aims to identify the effect of chitosan coating, ultraviolet a (UVA) light, and combined UVA-Chitosan treatments on blackcurrant postharvest storage. Physical (weight loss and firmness) and physiochemical analyses (soluble solid content, pH, citric acid content, and ascorbic acid content) were combined with microbial population quantification, phenolic compound characterization, and antioxidant capacity assessment. Samples were evaluated every three days of storage throughout this experiment. The results indicated that chitosan treatments have positive effects on reducing berry weight loss, maintaining berry firmness, and reducing mold populations. UVA influenced certain bioactive compounds, such as cyanidin-3-galactoside and rutin. The interaction effects from these two treatments were minimal. This study provides important information for blackcurrant postharvest storage and further small fruit storage work, considering both UVA and chitosan had differential beneficial effects on blackcurrant berries’ physical and chemical attributes.

In the past few years, there has been an increased interest in the use of biostimulants for improved crop production. Biostimulants are products that can promote plant growth when applied in amounts so small that they do not provide much nutrition. These are composed of different organisms, compounds or plant extracts; they include beneficial fungi and bacteria, humic and fulvic acid, seaweed extracts, and protein hydrolysates. During the 2022-23 growing season we evaluated three different biostimulant products in annual hill strawberry plasticulture production. ‘Ruby June’ plants were transplanted on 24 Oct, 2022 on non-fumigated beds and were maintained as per grower standard practices. Treatments were as follows (i) no biostimulant (ii) preplant AminoSalmon (247 kg/ha) applied during bed making (3) plugs dipped for 20 seconds in TerraGrow Liquid (TGL, 3ml/38 L) prior to transplanting followed by a foliar spray and a drip application (1.5L/ha) at one, fourteen, and thirty days after transplanting, resuming monthly during spring; and (iv) EZ-GRO 16-0-0 (3.9 kg/ha) drip application 14 days after transplanting and every 14 days during fall, resuming during spring. All non-treatment irrigation valves were closed during treatment injection through the drip lines. Ripe fruit was harvested beginning 31 March and continued twice a week until 16 June. Harvested fruit was categorized into marketable and non-marketable yield by replicate and fruits were weighed for each category. Yields were cumulated for the season and expressed as g/plant for data analysis. For total yield and marketable yield, no treatment differences were found. Fruit size was estimated as g/fruit by weighing 10 marketable fruits weekly. Five marketable fruits were measured weekly for firmness using a texture analyzer then stored at -20 °C for later analysis of pH and total soluble solids (°Brix) using a digital refractometer. While fruit firmness and pH were not influenced by treatments, the application of both the amino salmon and EZ-GRO biostimulants significantly improved total soluble solids values compared to the untreated control.

The Genome Database for Vaccinium (www.vaccinium.org) is a valuable resource for genomics, genetics, and breeding research related to blueberries, cranberries, bilberries, and lingonberries. It provides a wide range of genetic data, including genetic markers, linkage maps, and GWAS/QTL alongside genome data. GDV has the MapViewer tool to dynamically view genetic maps as well as genetic data associated with genomes and powerful search interfaces to query and download genetics data in table formats. For Vaccinium breeders, The Breeding Information Management System (BIMS) is a useful tool for storing, managing, archiving, and analyzing breeding data. Additionally, BIMS can be synchronized with the Field Book App to allow efficient phenotypic data collection and management. This poster will provide an update on new data and tools such as BIMS and MapViewer incorporated in GDV. We will demonstrate how these data and tools can be used for research and breeding activities.