Asmita Paudel, Youping Sun, Larry A. Rupp, and Richard Anderson
Kynda R. Curtis, Tatiana Drugova, Trevor Knudsen, Jennifer Reeve, and Ruby Ward
This study examines consumer preferences and willingness to pay (WTP) for organic and eco-friendly peaches, Prunus persica L., over conventional peaches in Utah. Data were collected at farmers’ markets across Utah, including actual peach purchases coupled with an in-person survey and analyzed using logit models. The results show that farmers’ market shoppers are willing to pay a premium for organic and eco-friendly peaches of $2.10 and $1.41 per pound, respectively. The importance of selected sustainability attributes positively impacted shopper preferences for eco-friendly peaches, while attitudes and lifestyle were associated with stronger shopper preferences for organic peaches. The distinct differences between shoppers who prefer organic and those who prefer eco-friendly, as well as the disparity in premiums, imply that growers should strongly consider their markets and cost of production differences when choosing organic certification over other less expensive differentiation schemes.
Larissa Larocca de Souza and Marcelo L. Moretti
Hazelnut (Corylus avellana L.) basal sprouts, or suckers, are removed to train trees as a single trunk, facilitating mechanization. Suckers are routinely controlled with herbicides, often by using nozzles that generate fine droplets and spray volumes as high as 934 L·ha−1, making spray drift a concern. Spray nozzle type and carrier volume can impact herbicide efficacy and drift. Field studies compared the efficacy of 2,4-D and glufosinate in controlling suckers when applied with a flat-fan nozzle, producing fine droplets, to a TeeJet air-induction nozzle, producing ultra-coarse droplets. These nozzles were evaluated at 187 and 374 L·ha−1. Nozzle and carrier volume did not affect the efficacy of 2,4-D based on control, sucker height, or dry weight. The efficacy of glufosinate was unaffected by nozzle type or spray volume in most evaluations. These results indicate that hazelnut suckers can be effectively controlled using drift-reduction nozzles with lower carrier volumes (187 L·ha−1). Drift-reduction nozzles, coupled with lower spray volume, can maintain herbicide efficacy, minimize drift risk, and reduce cost.
Huan Hu, Nan Chai, Haoxiang Zhu, Rui Li, Renwei Huang, Xia Wang, Daofeng Liu, Mingyang Li, Xingrong Song, and Shunzhao Sui
Wintersweet (Chimonanthus praecox) is one of the most popular winter-blooming species. Effective vegetative propagation is necessary for commercial usage and protection of wintersweet. In the current study, the four factors, namely hormone type (A), hormone concentration (B), soaking duration (C), and medium (D), were assessed using an L16 (44) orthogonal test design. The hormone types include ABT (A1), α-naphthalene acetic acid (NAA) (A2), indole butyric acid (IBA) (A3), and indole-3-acetic acid (IAA) (A4); the hormone concentrations include 100 mg·L−1 (B1), 500 mg·L−1 (B2), 1000 mg·L−1 (B3), and 1500 mg·L−1 (B4); the soaking durations include 5 seconds (C1), 5 minutes (C2), 30 minutes (C3), and 3 hours (C4); and the mediums include perlite: peat in the ratios 1:0 (D1), 2:1 (D2), 1:1 (D3), and 1:2 (D4). The results showed that hormone and proper medium could significantly improve the cutting survival, rooting, and sprouting, whereas poor factor combinations, especially high hormone concentrations combined with long soaking durations may be threatened to the cuttings and rooting. In actual experiments, we successfully obtained an excellent rooting percentage (62.22%) of wintersweet from treatment No. 5 (A2B1C2D3), which is perlite and peat (1:1) as the medium and soaking the cuttings in 100 mg·L−1 NAA for 5 minutes as the hormone treatment. This combination can already meet the requirements for commercial production. A range analysis showed that the medium and hormone concentration were the most important factors affecting the cutting of wintersweet. An analysis of variance also showed that the medium and hormone concentration can significantly or extremely significantly affect most cutting indicators. Moreover, our results revealed that an orthogonal design method is an effective tool for establishing an improved technique for cutting propagation.
Lili Zhou, Maria Eloisa Q. Reyes, and Robert E. Paull
Papaya (Carica papaya L.) leaves are large, up to 70 cm wide, and frequently deeply lobed, with seven to 13 major veins. The scan width of current handheld digital leaf area instruments is generally less than 15 cm. A rapid method is needed to estimate the total leaf area of a plant in the field with leaves at different stages of growth from the apex. The length of the main and side veins of papaya leaves can be used to estimate the area of a single leaf and the total leaf area of the plant. The relationship between main vein lengths and total leaf area was determined for mature leaves from the cultivars Sunset, Line-8, and Kapoho. A simple relationship exists between leaf area and the length of the two main side midribs (L3 and L4): Leaf area (cm2) = −2280 + 87.7*L3 + 55.6*L4 (P > F = 0.0001; r 2 = 0.969), explaining ≈94% of the variation between estimated leaf area and leaf area. The most recently matured leaf is the third or fourth discernable leaf from the apex, with a positive net photosynthetic CO2 assimilation rate and an average area of 2331 cm2 that could fix up to 1.6 g carbon per 10-hour day under full sun. The rate of photosynthesis declined with leaf age, and the overall net photosynthetic CO2 assimilation rate of the plant can be predicted. Following 80% leaf defoliation of the plant, the net photosynthetic CO2 assimilation rate of the most recently matured leaf increased 30% to 50% on days 11 and 19 after treatment when the photosynthetic active radiation (PAR) was approximately half of that on day 15 under full sun when no difference in net photosynthetic CO2 assimilation rate was seen. Fruit removal did not affect the net photosynthetic CO2 assimilation rate. Papaya adjusts its single-leaf net photosynthetic CO2 assimilation rate under lower light levels to meet plant growth and fruit sink demand.
Gianna Ricci and F. Bailey Norwood
The purpose of this study is to evaluate the appearance, texture, color, and taste of two popular pecan (Carya illinoinensis) clones relative to native pecans in a blind sensory analysis. Subjects tasted the raw pecans acquired from the same farm and evaluated them using hedonic scores. Results suggest consumers prefer the two clones to natives, and most of this preference seems to be related to the pecan size. A crossmodal effect was detected whereby the subjects reported an improved flavor in whole native pecans compared with clones that were cut in half and were thus less visually appealing. Consequently, although a previous study showed that consumers prefer pecans in a hypothetical (nontasting) situation when they are labeled as a “native” as opposed to clones, when the pecans are actually eaten and there are no labels designating the pecan type, they prefer the clones.
Ricardo Goenaga, Angel Marrero, and Delvis Pérez
Dragon fruit (Hylocereus sp. and Selenicereus sp.), also referred to as pitahaya or pitaya, is a member of the Cactaceae family and native to the tropical forest regions of southern Mexico, Central America, and northern South America. Its fruit is becoming increasingly popular as consumers seek healthy and more diverse food products. The crop adapts to different ecological conditions ranging from very dry regions to wet ones receiving more than 3500 mm of rainfall per year. U.S. commercial production of dragon fruit occurs mainly in Florida, southern California, and Hawaii. As growers learn more about this crop and how productive it can be, the acreage planted is likely to increase. Twelve dragon fruit cultivars grown on an Oxisol soil were evaluated for 5 years under intensive management at Isabela, PR. There were significant differences in number and weight of fruit per hectare among years. Cultivars exhibited an increase in fruit number and yield from 2010 to 2013 and then leveled off or declined. There were significant differences among cultivars for number of fruit and yield per hectare. Cultivars N97-17 and N97-15 produced significantly more fruit averaging 74,908 fruit/ha. Significantly higher fruit yield was obtained by cultivars N97-17, N97-20, N97-22, and NOI-13 averaging 17,002 kg·ha−1. Cultivar Cosmic Charlie had the lowest fruit yield, averaging only 25.1 kg·ha−1. Individual fruit weight was significantly higher in cultivars N97-20 and NOI-13 with fruit weight averaging 346.3 g. Cultivars NOI-16, N97-18, and Cosmic Charlie had significantly higher fruit soluble solids than others, averaging 17.4%. Some of the cultivars used in this study have shown horticultural potential and may serve as new planting material for growers.
Subhankar Mandal and Christopher S. Cramer
Fusarium basal rot (FBR) of onion, which is caused by Fusarium oxysporum f.sp. cepae (Hanzawa) Snyder & Hansen (FOC) results in a substantial loss of marketable bulbs worldwide. One of the main reasons for the lack of FBR-resistant short-day cultivars is the unreliable screening methods available for the mature bulb stage when significant economic damage occurs. The objective of this study was to develop an artificial inoculation method with better quantification of inoculum for an effective selection of FBR-resistant mature onion bulbs. Mature bulbs of seven New Mexican short-day onion cultivars, along with susceptible and tolerant controls, were selected and evaluated for FBR resistance using mycelial and conidial inoculation methods, respectively. Transversely cut basal plates of mature bulbs were inoculated artificially with mycelia or conidia (12 × 105 spores/mL in 2014 and 3 × 105 spores/mL in 2015 embedded in potato dextrose agar plug) of a virulent FOC isolate ‘CSC-515’. Mature bulb evaluation using a visual rating scale (1 = no disease; 9 = >70% basal plate infected) revealed a high degree of FBR severity and incidence irrespective of the genetic background of the cultivars, minimizing the chance of disease escape, which is a significant problem in field inoculation. An attempt to inoculate intact basal plates postharvest resulted in minimal disease development, suggesting that mechanical resistance was conferred by the dry outer layer of the basal plate. The high selection pressure conferred by the conidial inoculation method developed in this study can effectively screen FBR-resistant onion bulbs to replace an unreliable field screening. Concentrations of the conidia lower than 3 × 105 spores/mL are recommended to detect subtle genetic differences in FBR resistance among the onion cultivars and their selected population.
Xiaojing Duan, Zhonglong Zhu, Ziyang Sang, Faju Chen, and Luyi Ma
Jenny B. Ryals, Patricia R. Knight, and Eric T. Stafne
Production of passion fruit (Passiflora sp.) via cuttings is a way to eliminate genetic variation in the crop and also results in a faster establishment time. This could aid producers in increasing production efficiency while maintaining genetic lines. The objective of this research was to evaluate ease of rooting and determine the optimal auxin source for seven species of passion fruit. Semihardwood two-node cuttings were taken from the middle of the parent vine, and auxin treatments were applied to the basal end of the cutting. The cuttings were then stuck to a depth of 1 inch on 20 Aug. 2019. Treatments included three auxin sources and seven passion fruit species. Treatments were set up as a randomized complete block design blocking on species, with 10 single-plant replications per treatment. Data were collected 30 d after sticking cuttings and included percent rooted, total root number, average root length (of the three longest roots, measured in centimeters), root quality (0–5 scale, with 0 = dead and 5 = healthy, vigorous root system), root dry weight (measured in grams), and percent callus. Results showed that passion fruit cuttings receiving a hormone treatment had significantly positive effects on rooting responses, such as increased number, length, quality, and dry weight of roots. Blue passionflower (P. caerulea) was the only species in which hormone treatment did not increase rooting compared with the control. The use of hormone to aid in cutting propagation of passion fruit is recommended, depending on the species being propagated.