Aroniaberry or chokeberry (Aronia sp., Rosaceae) is an attractive new native fruit crop. Native to eastern and central United States, this deciduous tree-like shrub produces berries with one of the highest concentrations of anthocyanins compared to other fruits. Bred for northern climates, A. ‘Viking’ is the most popular fruit cultivar. Fruit production and quality of A. ‘Viking’, Red Chokeberry (A. arbutifolia), and black chokeberry (A. melanocarpa) was evaluated during the 2022 and 2023 growing seasons, in two locations in the state of Georgia: Blairsville (Zone 7a, Blue Ridge region) and Griffin (Zone 8a, Piedmont region). At both locations, 15 two-year old plants of each genotype were planted in 2021. All genotypes increased their yields between growing seasons (2022 to 2023) but the increment was much higher, and plants had higher yields in Blairsville. A. ‘Viking’ performed poorly in Griffin in 2022 (38.33 g and 119.4 average berries /plant) compared to plants in Blairsville (184.83 g and 237 average berries /plant); in 2023, Blairsville yields were 705.58 g and 1308 average berries /plant, but yields were almost zero in Griffin. A similar trend was observed in A. melanocarpa, with higher yields in Blairsville in the first year and no berry production in Griffin during the second year. A. melanocarpa was the genotype with the biggest increment in yield from 30.62 g and 21 average berries/plant in 2022 to 1111.41 g and 1594.95 average berries /plant in 2023 (Blairsville). A. arbutifolia had better yields in Blairsville compared to Griffin, but plants produced berries at both locations during both years. In terms of fruit quality, A. ‘Viking’ berries were tougher and with a stronger skin in Griffin, and there were no significant differences in texture from 2022 to 2023 in Blairsville. A. melanocarpa berries had similar texture and skin strength in both years. A. arbutifolia texture was similar in both locations in 2023, but in 2022 Griffin plants produced tougher fruit with stronger skin. Plants in Blairsville produced sweeter fruit compared to Griffin, across all genotypes.
Blackberry primocane growth management in the Southeastern US relies on tipping to manage vegetative growth. Tipping can increase lateral branching, bearing surface, and subsequent yield. However, the practice is labor intensive and expensive (~$600/acre). Furthermore, tipping wounds are sites for cane blight infection (Leptosphaeria coniothyrium) resulting in cane dieback, decline and death. Alternative strategies to tipping could reduce labor and fungicide inputs in a given season. Prohexadione calcium (P-Ca) is commonly used to control terminal shoot growth in other Rosaceous crops. We evaluated the relationship between P-Ca rate on blackberry vegetative and reproductive development. The experiment was conducted on a mature planting of ‘Osage’ floricane-fruiting blackberry at Clemson University’s Musser Fruit Research Center in Seneca, SC. The experiment had a completely randomized design with four replications. Treatments consisted of an untreated control and P-Ca applied at 62.5, 125, 250, and 500 ppm with a 0.125% (v:v) non-ionic surfactant and 0.39% (v:v) water conditioner. P-Ca treatments were applied 6 times at ~21 day intervals to the same plots across two consecutive years, 2019 and 2020. Regression analysis was conducted to determine the relationships between P-Ca and measured parameters. There was a consistent, negative relationship between P-Ca rate and primocane height across two years, which was linear in 2019 and curvilinear in 2020. A negative curvilinear relationship between P-Ca rate and yield was observed in 2020 beginning 8 weeks after P-Ca treatments were initiated until the final harvest. There were no consistent effects of P-Ca on fruit weight. P-Ca reduced total lateral length, number of lateral branches, and final cane length by 60 - 65% at the 250 ppm and 500 ppm rates. P-Ca is an effective growth retardant of blackberry, but the negative relationship between P-Ca rate and yield merits additional research. Future research should focus on post-harvest applications of P-Ca to minimize dormant pruning costs and applications in controlled environments.
Based on six years of research at the University of Arkansas, the rotating cross-arm (RCA) trellis has been shown to improve several aspects of blackberry production such as yield and fruit quality. Through this research, a new training method coined the ‘fan’ method was developed with the potential to maximize canopy fill and decrease labor. A trial was conducted from 2022 to 2024 at the University of Arkansas Fruit Research Station (UAFRS) in Clarksville, AR to verify the ‘fan’ method and test new cultivars not used in previous trials. The blackberry cultivars ‘Ponca’, ‘Von’ and ‘Caddo’ were planted in 2021 on a 33m row of t-trellis and a 33m row of RCA trellis in a randomized complete block arrangement. The plants were spaced 0.76 m apart in four plant plots replicated three times per trellis treatment. The ‘fan’ training method (primocanes tipped at 30 cm and laterals trained upward and fanned out on the long arm) was implemented on the RCA trellis treatment for all plants. The t-trellis was tipped at the top wire following practices standard for the region. Blackberry yield, fruit quality, and physiological data were collected during 2023 and 2024. Preliminary results from 2023 showed the ‘fan’ method on the RCA can achieve similar yields to the T-trellis but offer the opportunity to protect the crop from severe cold events and reduce the incidence of fruit quality disorders for some cultivars. All the varieties evaluated were found to be suitable for use on the RCA with the fan method however differences in cane vigor were noted and cultivar can be the biggest determinant of yield and fruit quality regardless of trellis type.
Due to its sweet and aromatic flavor, nutritional value, and health-associated beneficial compounds, strawberry (Fragaria x ananassa) is worldwide cultivated fruit crop. Texas strawberry cultivation is gaining popularity because strawberry production may give considerable economic returns in a relative short period of time. However, profitable strawberry cultivation is intricately tied to selection of suitable cultivars for prevailing environmental conditions. To identify the most appropriate cultivars for a specific region, it is critical to thoroughly evaluate strawberry cultivar growth, yield potential, and various quality characteristics within each diverse agro-climatic location. Hence, to evaluate strawberry cultivars for superior yield and fruit quality characteristics and determine suitable cultivars for cultivation in the region, this study was conducted at the TAMU AgriLife Research and Extension Center in Lubbock, TX. Twenty cultivars (8 day neutral and 12 June bearing) were established Fall of 2022 as bare root plants and data collection began Spring of 2023. Each cultivar was assessed for morphological, physiological, and agronomic traits. Trial results reveal significant variation in performance of evaluated cultivars. Yield and berry number were greatest for ‘Rikas’, ‘Cabrillo’, ‘Brilliance’, ‘Fronteras’, and ‘Beauty’, whereas ‘Keepsake’ was the lowest yielding cultivar and produced the fewest number of fruits. Berry size was greatest for ‘Monterey’, ‘Sweet Ann’, ‘Royal Royce’, ‘Cabrillo’, ‘Valiant’ and ‘San Andreas’, whereas ‘Keepsake’ had the smallest berries. Leaf gas exchange measurements revealed photosynthetic rate and conductance was least for ‘Sierra’. Fruit quality (total soluble solids, °Brix) was greatest for ‘Keepsake’ (11.9°) and lowest for ‘Radiance’ (7.6°). ‘Keepsake’ and ‘Victor’ fruit appeared to be resistant to Botrytis, whereas ‘Festival’ and ‘San Andreas’ were more susceptible. ‘Victor’ plants had the greatest percentage canopy green cover, whereas ‘Medallion’ had the least green canopy cover. Yield and fruit quality data indicate top day-neutral cultivar were ‘Cabrillo’, ‘Rikas’, and ‘Beauty’, while top June-bearing cultivars were ‘Brilliance’ and ‘Fronteras’. Preliminary research suggests cultivars ‘Rikas’, ‘Cabrillo’, ‘Brilliance’, ‘Fronteras’, and ‘Beauty’ may be adapted to the Lubbock area and do well for commercial strawberry cultivation. However, results are based upon data from a single growing season, and further research and analysis of data will confirm results.
Locally produced strawberries have outstanding market potential. Yet their production in the north-central US has declined, partly due to risks associated with the traditional matted-row system. While the plasticulture system offers promise, challenges like plug plant availability in late summer persist. Farmers may choose to use bare-root plants and plant in the summer. However, the high labor demand for planting bare-root plants on plastic and the intensive plant care in the summer have limited the use of plasticulture systems to small-scale operations. High tunnels are widely adapted for strawberry production worldwide. This structure protects plants from strong winds and rainfall, providing additional heat units and moderate frost protection. Successful implementation in Indiana, particularly with fall-planted strawberries, has demonstrated significant yield potential. In our initial exploration, an active row cover management strategy, i.e., covering and uncovering the plants daily in the winter months according to temperatures, was employed during winter months. Although the management approach optimized the winter environment for plant growth, it added labor in crop management, and it may not be feasible for farmers who are not on-site during winter months. This study compares four winter cover management strategies in the 2021-2022 and 2022-2023 seasons: No cover (row covers were not used in the entire winter), Active with hoops (row covers were actively managed daily and placed on hoops), Passive with hoops (the beds were covered during the coldest period, row covers were not removed during the day and were placed on hoops), and Passive without hoops (the beds were covered during the coldest period, row covers were not removed during the day and were placed directly on plants). The study found that No cover resulted in lower minimum temperatures and higher average daily PAR. The active management treatment exhibited the highest relative humidity. Marketable strawberry yields were not significantly different among the covering treatments. However, aphid density was notably higher under covers compared to the no-cover treatment. Our findings indicate that active row cover management during winter was not necessary in the strawberry production system, as it did not significantly increase yield compared to passive management strategy or absence of row covers. Furthermore, the passive management strategy, while potentially advantageous in terms of temperature regulation, was not recommended due to the associated risk of elevated aphid populations.
The horticulture industry has seen an increase in the use of greenhouses as an alternative protected systems to grow strawberries (Fragaria ×ananassa Duch.). Growing strawberries in a greenhouse provides the opportunity for earlier and out-of-season harvesting. However, there is limited research on the phenological and physiological performance of strawberries grown in containers under greenhouse conditions. Therefore, this experiment aims to evaluate the phenological and physiological performance of containerized strawberries grown in a greenhouse. In this study, two day-neutral strawberry cultivars, ‘Albion’ and ‘San Andreas’, were planted in 1-gallon nursery pots using 100% pine bark substrate and evaluated for a 5-month growing season. The phenological stages of all flower buds were recorded daily on five selected plants per cultivar. Monthly data was collected on biomass and diurnal photosynthesis. The yield of all plants was recorded, and fruits were separated into marketable and culled categories. During mid-season plants became infected with black root rot (Pythium spp.), and the results reflect the effects of the disease progression. Although the flower phenology was similar between cultivars throughout the production cycle, differences were observed in biomass accumulation and yield. ‘San Andreas’ showed higher growth over time and a decreased proportion of cull fruits during the Pythium infection. The cultivars evaluated showed similar trends in physiological processes, such as assimilation rate, evapotranspiration, intercellular carbon, stomatal conductance, leaf vapor pressure deficit, and quantum efficiency of photosystem II. Although not consistent, ‘San Andreas’ showed significantly higher values for some physiological parameters. These results indicate that strawberry growth and yield differ between cultivars in the greenhouse environment, which could be related to physiological factors that can ultimately translate to differences in disease susceptibility and performance The initial preliminary results of the first experiment indicates that strawberries can be cultivated with satisfactory results in a greenhouse. This alternative method can offer extended growing seasons, allowing for controlling environments, better disease control management, and easier pest control. Moreover, the portability of containers provides flexibility for the producer to arrange plants for space utilization.
Anthracnose fruit rot (AFR) caused by Colletotrichum acutatum is a major strawberry pathogen in the U.S. affecting both perennial and annual systems. This pathogen can survive in the soil rhizosphere from the previous seasons. Anaerobic soil disinfestation (ASD), an alternative to chemical fumigation methods, has been shown to effectively suppress a wide range of soilborne pests. Beneficial bacteria, such as Bacillus spp., are important biocontrol agents due to their capacity to reduce the growth of pathogens while also promoting plant growth. We proposed that ASD, beneficial bacteria, and their combinations could reduce fruit rot diseases of strawberries and improve crop yield and fruit quality parameters. A trial was conducted using a split-plot design with four replicates at the Hampton Roads AREC, Virginia Beach, VA. ‘Chandler’ strawberry plug plants were planted in various treatments as stated below: non-disinfested field plots (Control); field plots treated with Pic-Clor60 at 196 kg/ha (preplant soil fumigant) (Pic); field plots treated with ASD alone. Additionally, strawberry plants in each of these main treatments were treated with one of the following sub-treatments: no beneficial bacteria (untreated control), Bacillus velezensis only; TerraGrow (a mixture of five Bacillus spp.) at 1.7 kg/ha only; and TerraGrow 1.7 kg/ha applied 4 hours post Oxidate 5.0 (27% hydrogen peroxide, 5% acetic acid and 5% peroxyacetic acid) at 23,385 L/ha. Fruits were harvested twice per week starting 5 April through 20 June, 2023. Harvested fruits in each replicate or sub-plot were sorted into marketable and non-marketable categories. Non-marketable fruits included diseased fruits, small fruits or deformed fruits. Fruit weights were summed for the season by replicate and expressed as g/plant. Fruit firmness and total soluble solids (TSS) were measured on five representative marketable fruits per replicate once per harvest week and data were averaged for the season. For AFR, the weight of diseased fruits decreased significantly in sub-plots treated with B. velezensis, TerraGrow, and TerraGrow post Oxidate compared with the untreated control. In general, the ASD treatment significantly decreased the weight of AFR diseased fruits compared to the control and Pic-Clor 60 fumigation treatments. Fruit from ASD treated plots showed increased firmness and higher Total Soluble Solids values compared to Pic-Clor 60 plots. However, the marketable and total yield was lower in the ASD plots compared with other treatments. Our findings indicate that the utilization of beneficial microorganisms with ASD has the potential to reduce fungal diseases in annual hill strawberry production system.
Identifying storage conditions for strawberry liners propagated in controlled environments is needed to enable mass production of plant material for field growers. The objective was to compare the effect of crown diameter (CD), light, and temperature during cold storage (CS) on growth and subsequent yield of ‘Albion’ strawberry liners propagated indoors for 4 weeks under 24 or 16 h·d–1 (experiments 1 and 2, respectively) using white light-emitting diode fixtures. After propagation, plants of two CD (small 10mm) were stored during 4 weeks under 24 temperatures (ranging from -2 to 7 C) and 47% relative humidity, with or without 5 μmol·m–2·s–1 of white light provided for 24 h·d–1. Plants were moved to a common greenhouse compartment after each CS experiment and grown for 8 weeks to evaluate carryover effects on fruit yield. Overall, shoot and root dry mass were lower in plants exposed to CS compared to the initial baseline material, indicating a general loss of biomass during CS, regardless of treatment. The use of light did not affect any of the parameters evaluated, indicating that liners can be stored under darkness. In experiment 1, plants with large CD had higher chlorophyll concentration than those with small CD, but the opposite trend was measured in experiment 2. As expected, plants with large CD had longer petioles and produced more shoots during CS than those with small CD, regardless of experiment. Plants stored under ≤ -1.4 or -1.9 °C for experiments 1 and 2, respectively, died during the carryover phase, suggesting that liners should not be stored at or below these low temperatures. However, no treatment differences were measured after the carryover phase for plants stored in all other treatments. Further results highlighting the effect of temperature during CS will be presented.
