NHAES Inspired Horticultural Report, Summer 2022

NHAES INSPIRED Horticultural Report, Summer 2022

What's inside the Inspired Horticultural Research Report?

The research briefs in this report cover a diverse set of issues and exciting opportunities for horticultural production in the Granite State and northern New England. The topics include using DNA-based methods to develop new crops for our region, testing alternative management approaches that could allow the production of warmer-climate crops in our state and determining whether seafood byproducts can be repurposed as biopesticides for tree fruits, to name just a few. Each brief offers a snapshot of the rigorous science and practical takeaways that can make individual farming operations more successful and, collectively, strengthen the Granite State through science.

Read and download a pdf version of the entire publication below, or check out the individual Inspired Horticultural research articles below. And sign up for the NHAES newsletter to receive the latest updates on future editions of the Inspired research report.

Research Inside

Kiwiberries: A New Crop for the Northeast

The kiwiberry is a woody perennial climbing vine that produces clusters of small, grape-sized kiwi-like fruit. Due to high levels of carotenoids and anthocyanins, the nutritious flesh of a kiwiberry can assume a wide range of attractive colors, from dark greens to yellows to reds to purples. The fruit is high in vitamin C and one of the richest. sources of lutein (an antioxidant) in commonly consumed fruits.

Breeding Edible and Ornamental Strawberries for New England

The cultivated strawberries has four times as many chromosome sets as humans, animals and most other crops, which significantly increases its genomic complexity. Research to untangle the plant's genetic structure will enable scientists to more quickly and effectively develop cultivated strawberry varieties that help New England farmers be more resilient and successful.

Table Grapes: Determining Ideal Training Systems and Cultivars for New Hampshire

Table grapes are a relatively new crop for the Northeast. Several new varieties – released since the 1970s – may be better adapted to our climate than the typical table grapes grown in California. The specific cultivars of table grapes grown and the way their vines are managed can impact productivity, fruit quality and disease susceptibility.

Growing Figs in Cold Climates

Figs are grown commercially in mild climates where winter temperatures do not routinely fall below 10°F. In 2017, research began to successfully over-winter figs grown in-ground in northern New England. The research studied the effects of row covers, low tunnels and high tunnels on winter survival rates, plant growth and fruit yield for several varieties.

From Native Plants to New Crops: De Novo Plant Domestication in New England

Northern New England weeds could be domesticated and enriched with traits making them suitable for cultivation, like more compact sizes and larger seeds that remain on the plant during maturity, through an accelerated breeding process known as de novo domestication. Researchers found that three traits (plant height, degree of branching and time of initial flowering) all correlated.

Using Seafood Byproduct Chitosan as a Natural Disease Suppressant for Apples

Management of tree fruit diseases is especially challenging in the northeastern United States due to ideal climatic conditions for pathogen spread and infection leading to devastating fruit losses. Current research focuses on whether seafood byproducts can provide sustainable, cost-effective disease and pest management for New Hampshire growers battling tree fruit diseases.

Identifying the Highest-Yielding Varieties of Brussels Sprouts for New Hampshire

Rapid turnover in the commercial availability of Brussels sprout cultivars – coupled with dramatic differences in the performance and adaptability among cultivars – make it a challenging crop for growers outside of major production regions to select varieties that will consistently perform well. This research focused on re-examining best-performing varieties for the northern New England region and updating recommendations.

High Tunnel Eggplant Varieties, Pruning and Postharvest Storing

In places where eggplant is frequently grown in greenhouses, various pruning systems are used to enhance plant productivity and growth. In this study, researchers compared 10 varieties of elongated Italian eggplants to determine whether pruning to a 2- or 4-leader system would impact yields (when compared with no pruning) and the effects of postharvest storage on different varieties.

Tomatoes: High Tunnel Pruning Strategies

Many tomato varieties suffer from a phenomenon called ‘June drop’ in which a plant's first four to five fruit clusters set perfectly, but the subsequent two to three clusters set poorly and the plant's productivity suddenly drops. Reducing fruit load early in the season could prevent this productivity drop. This research examined the impact of thinning and removing tomato fruit clusters on fruit weight, total marketable yields, prevalence of defects and season-long fruit production.

Disease Threats and Biofungicide Efficacy in Soilless Substrates

In greenhouse production, plants are not typically grown in soil but in soilless growth substrates. Substrate manufacturers have identified wood byproducts to be some of the most promising alternative sources of raw materials to use in substrate formulations. This research considers how wood substrate components affect the severity of soil-borne diseases in greenhouse horticultural crop production.


Hale I, Melo ATO, Gustafson H (2018). Sex-linked molecular markers for two cold-hardy kiwifruit species, Actinidia arguta and A. kolomikta. European Journal of Horticultural Science, 83(4), 236-246. DOI: 10.17660/eJHS.2018/83.4.4

Latocha P, Debersaques F, Hale I (2021). Actinidia arguta (Kiwiberry): Botany, Production, Genetics, Nutritional Value, and Postharvest Handling. Horticultural Reviews 48: 37-151.

Melo A, Bartaula R, Hale I (2016). GBS-SNP-CROP: a reference-optional pipeline for SNP discovery and plant germplasm characterization using variable length, paired-end genotyping-by-sequencing data. BMC bioinformatics 17(1)

Melo ATO and Hale I (2018). Expanded functionality, increased accuracy, and enhanced speed in the de novo genotyping-by-sequencing pipeline GBS-SNP-CROP. Bioinformatics. DOI: 10.1093/bioinformatics/bty873

Melo ATO, Guthrie RS, Hale I (2017). GBS-based deconvolution of the surviving North American collection of cold-hardy kiwifruit (Actinidia spp.) germplasm. PloS one 12(1), e0170580

Melo ATO and Hale I (2019). ‘apparent': a simple and flexible R package for accurate SNP-based parentage analysis in the absence of guiding information. BMC bioinformatics, 20(1), 108

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Hanna, HY (2009). Influence of Cultivar, Growing Media, and Cluster Pruning on Greenhouse Tomato Yield and Fruit Quality. HortTechnology, 19(2).

Hesami, A., Khorami, S., and Hosseini, SS. (n.d.). Effect of Shoot Pruning and Flower Thinning on Quality and Quantity of Semi-Determinate Tomato (Lycopersicon esculentum Mill.). Not Sci Biol, 2012(1), 108–111. www.notulaebiologicae.ro

Mitchell, BA, Uchanski, ME, and Elliott, A. (2019). Fruit cluster pruning of tomato in an organic high-tunnel system. HortScience, 54(2), 311–316. https://doi.org/10.21273/HORTSCI13487-18

Pathirana, CK, Sajeevika, IDC, Pathirana, PRS, Fonseka, H, and Fonseka, RM. (2014). Effects of Canopy Management and Fruit Thinning on Seed Quality of Tomato (Solanum lycopersicum L.) Variety Thilina. In Tropical Agricultural Research (Vol. 25, Issue 2). http://agritech.tnau.ac.in/seed_certification

Slatnar, A, Mikulic-Petkovsek, M, Stampar, F, Veberic, R, and Kacjan Marsic, N. (2020). Influence of cluster thinning on quantitative and qualitative parameters of cherry tomato. European Journal of Horticultural Science, 85(1), 30–41. https://doi.org/10.17660/eJHS.2020/85.1.4

Fields JS, Fonteno WC, Jackson BE, Heitman JL, Owen JS. (2014). Hydrophysical Properties, Moisture Retention, and Drainage Profiles of Wood and Traditional Components for Greenhouse Substrates. Hortscience. 49(6):827–32

Harris CN, Dickson RW, Fisher PR, Jackson BE, Poleatewich AM. (2020). Evaluating Peat Substrates Amended with Pine Wood Fiber for Nitrogen Immobilization and Effects on Plant Performance with Container-grown Petunia. HortTechnology. 30(1):107–16

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