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Open access

Ting Zhou, Jie Zeng, Yunlong Li, Xiaoqing Lu, Donglin Zhang, Xiaolong Cai, and Hong Chen

Open access

Zhanao Deng, Natalia A. Peres, and Johan Desaeger

Open access

Orlando F. Rodriguez Izaba, Ariana P. Torres, Maria I. Marshall, and Aaron W. Thompson

Value-added (VA) technologies can help farmers in the specialty crops industry generate new products, increase off-season income sources, expand market access, and improve overall profitability. The United States Department of Agriculture defines VA agricultural products as those that have been changed physically or produced in a manner that enhances their value. Drawing from this definition, we investigated the adoption of VA technologies, such as drying, physical cutting into customer-ready portions, and washing, by specialty crops farmers. The objectives of this study were two-fold. First, we analyzed how market access drives specialty crop farmers to adopt VA technologies. Second, we addressed key identification issues by investigating the potential endogeneity between the adoption of VA technologies (vertical diversification) and the number of crops (horizontal diversification), which have not been addressed in the VA technology adoption literature. Data for this study were from a 2019 Web-based survey of specialty crops farmers in the United States. The results suggest that market access, growers’ networks, and crop diversification are major drivers of VA technology adoption in the specialty crops industry. The results indicate that farmers who adopted VA technologies experienced economic growth relative to their counterparts.

Open access

Yingbing Hu, Xiaoling Jin, Zhe Zhang, Minhuan Zhang, and Wenqian Zhang

Open access

Ruiyang Zhao, Juan Yang, Guiling Liu, Haijing Fu, Ling Wang, and Lijuan Fan

Open access

Hiromu Yamaguchi, Daisuke Yasutake, Tomoyoshi Hirota, and Koichi Nomura

Because the leaf area index (LAI) is an essential parameter for understanding the structure and growth status of plant canopies, nondestructive and continuous estimation methods have been required. Recently, an LAI estimation method using the ratio of near-infrared radiation (NIR; 700–1000 nm) to photosynthetically active radiation (PAR; 400–700 nm) (NIRin/PARin) transmitted through a canopy has been proposed. However, because previous studies on this NIRin/PARin-based LAI estimation method are limited to tall plants (e.g., forest and rice canopies), in this study, we applied this method to a short canopy (i.e., spinach) and investigated its validity. NIRin/PARin and three other traditional indices for indirect LAI estimation—relative PPF density (rPPFD), normalized difference vegetation index (NDVI), and simple ratio (SR)—were measured in 25 canopies with different LAI. NIRin/PARin showed better estimation sensitivity (R 2 = 0.88) to the observed LAI than the other three indices, particularly when LAI was greater than 3 m2·m−2. In addition, the LAI estimated from NIRin/PARin measured at 10-min intervals in the entire growth period could capture an increasing trend in the measured LAI throughout the entire growth stage (mean absolute error = 0.87 m2·m−2). Errors in long-term LAI estimations may be caused by the sensor location and insufficient data due to unsuitable weather conditions for measuring NIRin/PARin. The current study demonstrates the merits and limitations of the NIRin/PARin-based LAI estimation method applied to low height canopies, thereby contributing to its practical use in horticultural crops.

Open access

Patrick J. Conner, Gaurab Bhattarai, Haley N. Williams, and Eric T. Stafne

Muscadine grape (Vitis rotundifolia var. rotundifolia) is a rare crop in that it has transitioned from a wild fruiting plant to a domesticated fruit within the past 150 years. Furthermore, this domestication process was carried out by just a few institutions that published copious records of the origin and traits of the first wild selections, goals and methods of the breeding programs, and the pedigrees of releases. We thus have a near complete record of the domestication of this interesting fruit crop. Early breeding efforts made use of fewer than a dozen wild selections, most of which were collected from the coastal plain of North Carolina and South Carolina. This narrow germplasm base has led to increasing levels of inbreeding in the most recent muscadine cultivar releases. To better understand the germplasm base of muscadine, the pedigrees of 54 muscadine cultivars released since 1970 were examined. Only 15 founders (founding clones) were identified that appeared in more than two cultivars, and five of these represent open pollination events that may not indicate the addition of new genetic material. By far the most used founder was ‘Scuppernong’, which appeared in 53 of 54 pedigrees and had an average genetic contribution of 22.8%. The remaining founders varied from 0.9% to 14.8% in their average genetic contribution. Coancestry coefficients between cultivars averaged 0.18, but were often much higher among recent fresh-market releases. Analysis of vine vigor as measured by trunk caliper in seedling progenies suggests that coancestry coefficients greater than 0.23 result in below average seedling vigor. The University of Georgia muscadine breeding program is evaluating multiple wild muscadine accessions to reduce inbreeding and increase the genetic diversity of its germplasm.

Open access

Ayush K. Sharma, Amanpreet K. Sandhu, Simranpreet K. Sidhu, Winniefred D. Griffin, Navdeep Kaur, and Lakesh K. Sharma

Sulfur (S) is the fourth most essential nutrient after nitrogen (N), phosphorus (P), and potassium (K) with a direct role in amino acid syntheses, such as methionine, cysteine, and N assimilation. Potato is a fast-growing vegetable crop with a small crop cycle; therefore, nutrient applications at the appropriate time, place, rate, and source are essential. The objective was to determine the effect of different S sources on the potato tuber yield, specific gravity, external tuber quality, and internal tuber quality. This study was conducted in 2021 and 2022, and three S sources were applied at two different rates (T1, 45 kg⋅ha−1; T2, 90 kg⋅ha−1) using a 3 × 2 factorial design. Three S sources were derived from the sulfate of ammonia (AS; SO4 2− source), magnesium sulfate (EPTOP; S0 source), and gypsum (SO4 2− source). Three potato cultivars were used for this study (Atlantic, Satina, and Red La Soda). The total and marketable yields indicated a positive response to the application of the S sources. Gypsum and EPTOP outperformed AS, and the lower rate (T1) performed better than the higher rate (T2). In one of the trials, the maximum yield difference between AS and gypsum was 33%. The maximum specific gravity for cultivar Atlantic was found with AS and gypsum, whereas Red La Soda and Satina did not respond to any S source. We did not report the treatment effects on the external and internal disorders when weather affected them.

Open access

Kyle Brasier, Ingrid Zaragoza, Jacob Knecht, Rebecca Munster, Hope Coulter, Amanda Potter, Elizabeth Enke, Aaron Fox, Elizabeth Mosqueda, and Hossein Zakeri

Cover cropping has been strongly promoted, but few growers have realized the benefits of this practice due to challenges linked to economic returns and whole-system management. In the western United States, winter legumes including faba bean have the potential to add economic value while offering soil health benefits compared with fallow fields. This experiment assessed the potential of five vegetable faba bean varieties for fresh pod yield, fresh pod quality, and biomass N return under a single and multiple pod harvest scheme. Vegetable faba bean varieties were further compared with two popular cover crop faba bean varieties, ‘Bell bean’ and ‘Sweet Lorane’ for cover crop and biomass N return benefits. The experiment revealed significant (P ≤ 0.05) genotypic variation for vegetable fresh pod yield, dry biomass, fresh pod quality, pod N removal, biomass N return, and C:N in three testing environments under the single and multiple harvest schemes. Finally, the vegetable variety ‘Vroma’ produced high average fresh pod yield under the single (16,178 kg·ha−1) and multiple (38,928 kg·ha−1) harvest schemes while maintaining high biomass N return under the single (119 kg·ha−1 N) and multiple harvests (97 kg·ha−1 N) compared with the cover crop varieties (128 kg·ha−1 N). This experiment demonstrated that a single fresh pod harvest on an early and high yielding faba bean variety can generate economic returns while also providing cover crop benefits that are comparable to termination of a faba bean cover crop on the same date.