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Open access

Han-Na Seo, Hyo-In Lim, Yong-Yul Kim, Seung-Beom Chae, and Wonwoo Cho

Identifying the morphological characteristics that distinguish plant varieties is an important issue for plant breeders and researchers. The objective of the present study was to create a partial least squares discrimination analysis (PLS-DA) model with morphological characteristics for species discrimination and to select the characteristics most important for species discrimination. Data for 27 vegetative characteristics were obtained from Salix caprea and Salix gracilistyla, and their interspecific hybrid (S. caprea × S. gracilistyla), and used for PLS-DA. According to this analysis, seven of the 27 characteristics were identified as those that most influenced species discrimination, and the PLS-DA model with these seven characteristics had a classification accuracy of 86% to 100%. The classification performance of this model was not significantly different from that of the model with all 27 characteristics (full model). Therefore, these results indicated that the three species can be relatively well distinguished by the seven characteristics extracted by PLS-DA. In addition, the selected characteristics can be used to select cross-breeding parents in subsequent breeding programs and to test the distinction, uniformity, and stability (DUS test) of the hybrid variety. From this perspective, PLS-DA is thought to be a useful methodology for classifying new plant varieties and providing information for breeding.

Open access

Tanner Donahoo, Lisha Zhang, Matthew Cutulle, and Abolfazl Hajihassani

Increasing regulations and restrictions regarding on-farm chemical use and growing consumer demands for organic food products warrant the development of efficient biological methods for plant disease control and pest management. Grafting and anaerobic soil disinfestation are two sustainable crop production techniques developed to control and regulate weeds, root-knot nematodes (Meloidogyne incognita), and soilborne pathogens. Therefore, the present study explores the economic impact of using grafting and anaerobic soil disinfestation, independently and in conjunction, to determine the best combination in terms of yield and net returns for producers. This study drew from tomato (Solanum lycopersicum) field trials conducted in 2020 on a 0.5-acre plot at the Clemson Coastal Research and Education Center in Charleston, SC, where five grafting and three anaerobic soil disinfestation treatments were used in combinations for comparisons. Each treatment combination was subjected to sealed (plastic mulch covering a plot punctured 5 weeks after applying anaerobic soil disinfestation treatment) and unsealed (plastic mulch covering a plot punctured immediately after the application of anaerobic soil disinfestation treatment) plot conditions during the anaerobic soil disinfestation phase of plant bed preparation. Treatment combinations with cottonseed meal carbon-sourced anaerobic soil disinfestation were unviable because of lower net returns compared with treatment combinations without anaerobic soil disinfestation in nearly every case. Grafting (‘Roadster’ self-grafted) combined with molasses and chicken manure carbon-sourced anaerobic soil disinfestation under unsealed plot conditions was the most optimal treatment combination in the field trials with the greatest gains (net return per acre) to producers. The positive synergistic effects of combining these methods suggest that grafting and anaerobic soil disinfestation yield better results in conjunction than separately.

Open access

Ved Parkash, Sukhbir Singh, Manpreet Singh, Sanjit K. Deb, Glen L. Ritchie, and Russell W. Wallace

Water scarcity is increasing in the world, which is limiting crop production, especially in water-limited areas such as Southern High Plains of the United States. There is a need to adopt the irrigation management practices that can help to conserve water and sustain crop production in such water-limited areas. A 2-year field study was conducted during the summers of 2019 and 2020 to evaluate the effect of deficit irrigation levels and cultivars on root distribution pattern, soil water depletion, and water use efficiency (WUE) of cucumber (Cucumis sativus). The experiment was conducted in a split-plot design with four irrigation levels [100%, 80%, 60%, and 40% crop evapotranspiration (ETc)] as main plot factor and two cultivars (Poinsett 76 and Marketmore 76) as subplot factor with three replications. Results showed that root length density (RLD) was unaffected by the irrigation levels in 2019. In 2020, the RLD was comparable between 100% and 80% ETc, and it was significantly higher in 100% ETc than both 60% Eand 40% ETc. Root surface area density (RSAD) was not significantly different between 100% and 80% ETc, and it was significantly lower in both 60% and 40% ETc than 100% ETc in both years. Soil water depletion was the highest in 40% ETc followed by 60% and 80% ETc, and it was least in 100% ETc in both years. Evapotranspiration (ET) was the highest in 100% ETc followed by 80%, 60%, and 40% ETc. The WUE was not statistically different among the irrigation treatments. However, numerically, WUE was observed in the following order: 80% ETc > 100% ETc > 60% ETc > 40% ETc. The RLD, RSAD, soil water depletion, and ET were not significantly different between ‘Poinsett 76’ and ‘Marketmore 76’. However, fruit yield was significantly higher in ‘Poinsett 76’ than ‘Marketmore 76’, which resulted in higher WUE in Poinsett 76. It can be concluded that 80% ETc and Poinsett 76 cultivar can be adopted for higher crop water productivity and successful cucumber production in SHP.

Open access

Maheshwari Asha, Mmbaga Margaret, Bhusal Bandana, and Ondzighi-Assoume Christine

Bacterial endophytes selected for their capability to suppress diverse fungal pathogens in vitro and in greenhouse studies have been shown to promote plant growth. The effect of volatile compounds emitted by selected bacteria on plant growth in Arabidopsis thaliana, tomato (Solanum lycopersicum), sweet pepper (Capsicum annuum), and cucumbers (Cucumis sativus) was evaluated on container-grown plants nested above bacterial cultures, with roots exposed to the volatiles without direct contact between bacterial cells and the plant roots. Significant increases in plant growth were observed in plant height, root length, leaf size, fresh weight, and chlorophyll content in all plants tested. Although diverse chemical compounds may be involved in promoting plant growth, including volatile and nonvolatile compounds, observations in this study have implications for the potential role of the selected bacteria in plant production as biofertilizers and biopesticides.

Open access

Juliano Martins Ramalho Marques, Ariana P. Torres, Bridget K. Behe, Petrus Langenhoven, and Luiz Henrique de Barros Vilas Boas

Before consumers choose what and how much fruit to buy, they first decide where to buy it. To address the choices of stores for fresh fruits, this study investigated the influence of market attributes and customers’ attitudes toward their purchasing decisions. Data from a web-based survey of 1658 U.S. consumers were used to conduct multinomial logit regression to investigate the factors guiding their choices regarding four types of stores: chain, independent, club/warehouse, and direct-to-consumer. We found attitudinal scales and market attributes have different effects on the choice of marketplace for fresh fruits. Driven by price and convenience, most consumers prefer chain stores when buying fresh fruits, whereas those same factors deter them from choosing independent and ethnic stores for fresh fruits. The supply of local fruits, friendly atmosphere, and access to desirable fresh fruits positively influenced consumers to purchase fruits at local markets. Our findings can provide insight regarding food retailers and farmers targeting fresh fruit consumers. For example, our findings highlight the importance of providing a friendly atmosphere and outstanding customer service to positively influence purchasing behavior.

Open access

Analena B. Bruce, Elizabeth T. Maynard, Julia C.D. Valliant, and James R. Farmer

High tunnels are a low-cost technology that can strengthen local and regional food systems and have been shown to help farmers extend the growing season and increase the yield and shelf life, and improve the quality of their crops. This study addresses a need for a better understanding of farmers’ experience with integrating high tunnels into their operations, to understand the human dimensions of high tunnel management. We present an analysis of survey and interview data to examine how farm characteristics affect the outcomes of growing specialty crops in high tunnels. Our findings show that farmers managing different types of farms have taken distinct approaches to integrating and managing high tunnels on their farms, with important implications for farm-level outcomes. We identify three types of farms commonly adopting high tunnels in Indiana: 1) alternative food and agriculture enterprises (AFAEs) are consumer-oriented, small-scale farms that sell their products directly to their customers in relationship-based market networks such as farmers’ markets and community-supported agriculture; 2) mixed enterprise farmers have larger operations and sell into both conventional commodity markets and direct markets; and 3) side enterprise farmers operate small-scale enterprises and their primary household income comes from off-farm employment or another business. Farm type is associated with divergent levels of time and labor investment, resulting in higher capacity use of high tunnels and greater financial return for AFAE farmers who make high tunnels central to their business, compared with mixed and side enterprise farmers who invest less time and labor into their high tunnels. We explain how farm characteristics and approaches to adopting the infrastructure shape farmers’ success and high-capacity use of high tunnels.

Open access

Yasmina Chourak, El Hassan Belarbi, Evelynn Y. Martínez-Rivera, Tatiana Pagan Loeiro da Cunha-Chiamolera, Ana Araceli Peña-Fernández, José Luis Guil-Guerrero, and Miguel Urrestarazu

Saffron is one of the most appreciated, traditional, and expensive spices in the world. The objective of our study was to evaluate the effect of cooling the nutrient solution on the production, and organoleptic and commercial qualities of saffron grown in soilless culture. The nutrient solution was cooled to 4 to 5 °C whereas the control treatment was the fertigation supplied at ambient temperature. Corms were placed in a controlled cultivation chamber. The number of flowers per corms, and the weight and length of stigmas were measured. The amounts of safranal, crocin, and picrocrocin were analyzed spectrophotometrically according to the International Organization for Standardization [ISO/TS 3632-2 (2011) Normative]. Our results show that cooling of the nutritive solution increased flower production, the commercial phytochemical content, and organoleptic properties.

Open access

David R. Coyle, Brayden M. Williams, and Donald L. Hagan

Callery pear (Pyrus calleryana) is an invasive tree across much of the eastern United States that can form dense thickets, and tree branches and stems are often covered in sharp thorns. Landowners and land managers attempting to manage callery pear infestations are faced with the challenge of killing and/or removing the trees while also avoiding thorn damage to equipment, which can lead to wasted time and increased costs. We evaluated fire as management tool to reduce the likelihood of equipment damage from callery pear thorns. Branches were collected in the field from callery pear trees that were killed by herbicide, and also from untreated trees, and half the branches from each group were then burned with a propane garden torch to simulate a low-intensity prescribed fire. After treatment, all branches were returned either to an old field or forest floor for 1 year, after which thorn puncture strength was evaluated and compared with freshly cut thorns. Herbicide treatment and location did not affect thorn strength, but burning reduced the likelihood that thorns would puncture a tire. Fire increased tip width, which reduced thorn sharpness. Burning also reduced wood strength, and fungi proliferated on burned thorns after 1 year in the field or forest. Both factors likely contributed to decreasing thorn strength and probability of puncture. Our results show that using prescribed fire as a management tool can weaken callery pear thorns and dull their tips, reducing the chance of equipment damage and costs associated with clearing land of this invasive species. Leaving cut callery pear trees on the ground for 1 year increased fungal colonization, which may also reduce thorn damage. Prescribed fire can be part of an effective integrated management plan for this, and possibly other, thorny invasive flora.

Open access

Chunlian Jin, Dan Sun, Chang Wei, Zhenhua Guo, Chunmei Yang, and Fan Li

Gypsophila paniculata is an ornamental crop with medicinal value. To date, limited information has been reported about the natural products in G. paniculata to explain its medicinal function. The current study reports the natural products found in G. paniculata stem for the first time. Thirty-three compounds were isolated from the extract of G. paniculata stem and identified by gas chromatography-mass spectrometry, 10 of which have contents >2%. These were 2-O-methyl-D-mannopyranose (37.4706%), glycerol (12.5669%), two tetratetracontane isomer (7.6523 + 3.5145%), tetrahygro-4-pyranol (5.3254%), 1,6-anhydro-beta-d-glucopyranos (4.7507%), palmitic acid (4.1848%), 4-hydroxy-3-methoxystyrene (3.7439%), methyl-octadeca-9,12-dienoate (2.7490%), and 2-deoxy-D-galactose (2.6193%). Another bioactive compound, condrillasterol, was identified with 1.3384% content. We also reported that G. paniculata possesses antioxidant activity possibly associated with the presence of a phenolic chemical 4-hydroxy-3-methoxystyrene. Our data collectively demonstrate that G. paniculata contains some bioactive compounds with high contents and antioxidants, consistent with its role as a medicinal herb.