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Utilizing quantum dot (QD) luminescent films as a greenhouse covering material is an innovative method of modifying the greenhouse light spectrum. The QD films convert a portion of high-energy ultraviolet and blue photons to lower-energy photons. Previous research has shown that the application of QD films in greenhouses led to improved crop yields of red lettuce and tomatoes. However, the underlying mechanism of the yield increases has not been fully explored. We quantified the effects of solar spectral shifts attributable to QD films on plant morphology, radiation capture, and, subsequently, crop yield. Green and red leaf lettuces and basil were grown in a greenhouse under four treatments: regular-concentration QD film (reg QD film); high-concentration QD film (high QD film); color-neutral polyethylene (PE) film; and control treatment without any films. Compared to the reg QD film, the high QD film converted a higher fraction of blue photons into longer-wavelength photons, resulting in enhanced leaf expansion, stem elongation, and shoot fresh weight of red lettuce and basil compared with those grown under the PE film without spectral modifications. No significant growth differences were observed between the control and high QD film treatments of red lettuce and basil despite a 23% reduction in the average daily light integral (DLI) under the high QD film treatment. Compared to that grown under the control treatment, green lettuce grown under the high QD film treatment had a similar total leaf area but reduced shoot biomass; this was likely associated with reductions in leaf thickness and chlorophyll content. In contrast, the red lettuce showed more pronounced leaf expansion and reduced leaf anthocyanin content under the high QD film, which likely helped to offset the reduction in DLI. Overall, our results indicated that modifying the solar spectrum with QD films as greenhouse covering material could result in improved crop radiation capture and yield in greenhouse production of lettuce and basil. However, the spectral shifts caused by the QD films may affect crop quality attributes, such as anthocyanin levels and the production of other beneficial secondary metabolites. This effect on crop quality should be carefully considered and requires further study.

Berry fruits produced by Vaccinium (Ericaceae) plants are small but have a signature flavor and have become increasingly popular in the 21st century. However, self-incompatibility (SI) results in a relatively low fruit-set ratio and reduced fruit quality in Vaccinium. In this study, using Vaccinium ashei (V. ashei) styles after cross-pollination (CP) and self-pollination (SP) as material, transcriptomics and gene expression analyses were performed using high-throughput RNA sequencing and quantitative real-time polymerase chain reaction (qRT-PCR). Subsequently, evolutionary analysis and conserved sequences analysis of candidate genes were conducted. Among the 135,324 unigenes, 30,863 were shown to be differentially expressed, and eight randomly selected differentially expressed genes were expressed in the styles at 96 hours after SP and CP. The transcriptomics and qRT-PCR results were significantly correlated, which confirmed the reliability of the differentially expressed genes obtained in our study. Compared with SP96, six differentially expressed ribonuclease T2 family genes were obtained in CP96, which were considered candidates for S-RNase. Additionally, the spatiotemporal and organizational expression trends of six candidates for S-RNase were confirmed by qRT-PCR, and the evolutionary and conservative sequence analysis indicated six candidate S-RNases with the typical S-RNase structure. The spatiotemporal and organizational expression results and evolutionary and conservative sequence analyses of the six candidate S-RNases suggest that SI in V. ashei is likely an S-RNase-mediated gametophytic one. This finding suggests the involvement of novel, previously undiscovered components involved in the V. ashei SI system. These findings help elucidate the molecular mechanisms of SI in rabbiteye blueberry and may also benefit breeding, production, and genomics research in V. ashei and other Vaccinium species.

Angelonia (Angelonia angustifolia) is an important potted flowering plant or bedding plant widely used in tropical and subtropical regions. However, most Angelonia cultivars have relatively small flowers and demonstrate limited drought tolerance in root-restricted environments such as small containers. Polyploid plants often exhibit larger flowers and enhanced drought tolerance. In this study, Angelonia ‘Serena White’ seeds and ‘Serena Purple’ seedlings were treated with 0.1% and 0.2% colchicine to induce polyploid lines, respectively. The resulting tetraploids had larger pollen and flowers, along with thicker, greener leaves distinguished by serrated edges, longer stomata, and lower stomatal density compared with diploid ‘Serena White’ and ‘Serena Purple’ plants. Both diploid and tetraploid plants subjected to a 20% volumetric water content (VWC) treatment exhibited smaller leaves, higher SPAD-502 readings, and a decreased number of flowers compared with those subjected to 40% VWC treatment. Moreover, tetraploids had higher photosynthetic rates than diploids under both 20% and 40% VWC conditions. When grown in 0.8-L containers, tetraploid plants required fewer watering events and had thicker, erect stems with larger flowers than diploids, even under a 20% VWC treatment. Colchicine-induced polyploidization presents a promising method to potentially enhance drought tolerance in angelonia.

Based on the International Camellia Register (ICR), an analysis of 1616 cultivars of Sasanqua that were registered in 2022 and earlier was conducted. This analysis focused on the resource and biological characteristics of the cultivars. Additionally, a trait diversity analysis, principal component analysis, and cluster analysis of 118 cultivars that had complete morphological records were performed. The findings revealed a rich diversity of Sasanqua cultivars, with Japan, the United States, and Australia being the main sources. The primary flower color was red, followed by multiple colors, white, and rare colors. The predominant flower forms were single-petal and semi-double-petal, with a limited number of formal double-petal forms. Elliptical leaf shapes were the most common, and the predominant leaf colors were green and deep green. The flowering period mainly corresponded to early flowering cultivars. The phenotypic diversity index (H) of the 118 cultivars ranged from 0.31 to 1.84. The flower diameter exhibited the highest H value (1.84), whereas leaf shape had the lowest H value (0.31). The coefficient of variation (CV) ranged from 21.67% to 71.81%, with the flower diameter having the smallest CV (21.67%) and petal number having the largest CV (71.81%). The first three principal components, which accounted for a cumulative contribution rate of 62.49%, effectively represented most of the information regarding the seven trait indicators of the different cultivars. Furthermore, a cluster analysis was conducted based on the flower form, diameter, petal numbers, and other characteristics of the various cultivars. The 118 cultivars were divided into three groups. The first group could be used for breeding single-petal flower cultivars, whereas the third group exhibited a larger number of petals and could be used for breeding double-petal flower cultivars.

Zebra-stem of tomato is a disorder characterized by leaf necrosis, wilting, and a stripped pattern on stems of mature plants. Wilting, necrosis, and death of seedlings are also observed. The physiological and genetic causes of zebra-stem are poorly characterized. Anecdotal evidence has suggested pedigrees with S. pimpinellifolium and bacterial speck resistance in the genetic background are often prone to this disorder. We demonstrate a genetic cause using composite interval mapping and association analysis approaches to define quantitative trait loci (QTLs) that contribute to the disorder. A biparental population of F₄ partially inbred families was developed for the initial analysis, and four subsequent backcross or F₂ populations were used for subsequent validation. Significant QTLs on chromosomes 5 and 10 were identified, explaining ∼60% and 40% of the variation, respectively. Polymorphisms in the Pto locus are strongly associated with the QTL on chromosome 5. The two loci were derived from different parentage, and a significant interaction effect was demonstrated, resulting in the characteristic zebra-stem symptoms when combined.

Lateral branching is an important agronomic trait in horticulture plants. The aim of this project was to reveal the genetic mechanism, map the gene localization, and predict candidate genes of watermelon lateral branching. An F₂ segregating population was derived from a cross between the multibranched maternal inbred line M6 and the branchless paternal inbred line N7. Two DNA pools were constructed using 20 multibranched plants and 20 branchless plants from the F₂ population. Whole-genome resequencing was performed for the DNA pools (25×) and the parents (30×) to identify the genomic region associated with lateral branching. Candidate genes were predicted based on the gene annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses; then, quantitative validation of these genes was performed. The results showed that the clean reads of four samples yielded 64,295,076 to 81,658,958 bp, with sufficient genome coverage and high quality. Based on single-nucleotide polymorphism and insertions/deletions association analyses, the candidate genes were mapped to a 2.01-Mb region on chromosome 4 (22,958,925–24,971,894 bp) containing 182 annotated genes. During the KEGG and GO enrichment analyses, these genes were annotated to 10 cellular components, 10 molecular functions, and 12 biological processes. Eight candidate genes responsible for the branchless phenotype in watermelon were identified: Cla97C04G076340, Cla97C04G075820, Cla97C04G076060, Cla97C04G076250, Cla97C04G076280, Cla97C04G076380, Cla97C04G076830, and Cla97C04G075950. These genes were involved in amino acid biosynthesis and catabolism, TCP transcription factor activity, and regulation of flower development. This study offers valuable insights into the molecular mechanisms governing the branchless phenotype in watermelon. These candidate genes serve as potential targets for gene cloning and marker-assisted selection of watermelon cultivars without lateral branches.

There is a growing trend toward planting native and pollinator-friendly plants in residential gardens and landscapes due to concerns about invasive plant species, water conservation, and urban land management. Yet, understanding consumer purchase behavior and how knowledge affects their purchase intent is largely unknown. In this analysis, we integrated national online and in-person surveys to determine the influence of consumers’ subjective and objective knowledge of native and pollinator-friendly ornamental plants on their purchase decisions. Factors influencing plant purchase decisions were measured using a 7-point Likert rating scale. We found that participants with relatively higher knowledge of native and pollinator-attractive plants placed more emphasis on sustainable production methods relative to the plant’s physical attributes (e.g., plant size, shape, etc.) and care-related characteristics (e.g., plant health, easiness of care, etc.). Plant lovers (i.e., frequent purchasers who spent relatively more money on plants than infrequent purchasers) were more likely to prioritize sustainable production methods over the plants’ physical attributes. In contrast, participants primarily buying plants from mass merchandisers/box stores tend to focus on visual appeal or aesthetic characteristics. Consumer marketing implications for the nursery and greenhouse industry stakeholders are discussed.

Lettuce (Lactuca sativa L.) is grown worldwide, from temperate to subtropical climates. Spring season production in humid, subtropical regions, such as southern Florida, is characterized by rising ambient temperatures that can stress lettuce to prematurely bolt and lose shelf life. The objectives of this research were 1) to identify genetic variability in heat tolerance and shelf life among lettuce types and accessions grown under humid, subtropical conditions, and 2) to understand the genotype × environment (G × E) interaction to estimate shelf life of these lettuce accessions. Five lettuce types (romaine, crisphead, butterhead, leaf, and Latin) were grown under commercial conditions in the Everglades Agricultural Area near Belle Glade, FL, USA, for five field experiments over two seasons. Lettuce heads were evaluated at harvest, and subsets were transported to a local commercial grower/shipper for vacuum-cooling and storage at 15 °C according to previously determined protocols for accelerated shelf life testing. Visual appearance ratings were made across harvests and storage time points to segregate lettuce accessions with an estimated marketable shelf life >14 days. The breeding lines tested in this research had head weight and marketability comparable to commercial cultivars. Notably, the crisphead accessions 50113, 60157, 60159, and H1098 had the highest estimated and actual shelf life of more than 21 days, with no presence of bolting or tipburn. Meanwhile, romaine, butterhead, leaf, and Latin types had accessions with estimated and actual shelf life ranging from 14 to 28 days and no presence of bolting or tipburn. A G × E analysis indicated that this interaction is significant; therefore, breeders should consider analyzing G × E when developing new cultivars with good horticultural characteristics, longer shelf life, and most importantly, adaptation to warmer humid, subtropical conditions.

The effects of sole-source lighting on the growth and yield of hydroponically grown lettuce have been extensively studied, but research of postharvest performance is limited. We grew frill-leaf lettuce (Lactuca sativa) ‘Green Incised’ and ‘Hydroponic Green Sweet Crisp’ hydroponically in an indoor vertical research farm under daily light integrals (DLIs) of 12 or 18 mol⋅m⁻²⋅d⁻¹ and the following three ratios of blue (B; 400–499 nm) and red (R; 600–699 nm) light from light-emitting diode fixtures: B₅:R₉₅, B₂₀:R₈₀, and B₃₅:R₆₅. We postulated that biomass accumulation would increase with the DLI and decrease with the B light fraction, and that postharvest longevity would increase with the DLI and the B light fraction. As expected, shoot fresh weight, leaf length and width, leaf number, and relative chlorophyll content (SPAD; ‘Green Incised’ only) decreased as the proportion of B light increased from 5% to 35%. Decreasing the DLI from 18 to 12 mol⋅m⁻²⋅d⁻¹ reduced the shoot fresh weight and leaf number of both cultivars. Leaves of ‘Green Incised’ were up to 27% wider under B₅:R₉₅ and 60% longer under B₅:R₉₅ at 12 mol⋅m⁻²⋅d⁻¹ than those under treatments with a higher DLI or more B light. The shoot fresh weight of ‘Hydroponic Green Sweet Crisp’ was greatest when grown under B₅:R₉₅ at 18 mol⋅m⁻²⋅d⁻¹ and decreased as B light increased or DLI decreased. At the time of harvest, leaves of each cultivar and treatment were placed in clamshells and stored at 7 °C in darkness and evaluated for decay. ‘Green Incised’ that grew under B₃₅:R₆₅ and a DLI of 18 mol⋅m⁻²⋅d⁻¹ had the shortest storage life, with 9.5 d and 11.4 d for replications 1 and 2, respectively, which were ∼2.5 to 4.0 d and 1.4 to 3.6 d earlier, respectively, than the storage life of lettuce grown under other treatments. In contrast, ‘Hydroponic Green Sweet Crisp’ was not influenced by light quality or DLI and had a storage life of 12.6 to 13.3 d and 13.5 to 14.3 d for replications 1 and 2, respectively. Therefore, a B light fraction between 5% and 20% and a DLI of 18 mol⋅m⁻²⋅d⁻¹ produced high-yielding frill-leaf lettuce with a relatively long storage life.