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Variegated temple bamboo (Sinobambusa tootsik f. luteoloalbostriata) is one of the native variegated bamboo species has some whole green (WG) and whole white (WW) leaves in addition to striped green and white ones. The life span of WW leaves is short, but the life span of striped leaves (SLs) is unaffected by the area of white mesophyll, and the SL phenotype is well maintained. To explore the mechanism of phenotypic stability of SL, we took five leaf phenotypes as study materials: WG, WW, SL, the green part of SL (SG), and the white part of SL (SW). Through the measurement of photosynthetic pigments, leaf nutrient elements, chloroplast synthesis–related hormones and their precursors in the leaves, and antioxidant system parameters, we examined the antioxidant adaptation mechanism of the white mesophyll cells of S. tootsik f. luteoloalbostriata. The results indicated that abscisic acid (ABA) levels were substantially higher in WW leaves than in SW leaves, and salicylic acid (SA) levels were significantly higher in SW leaves compared with WW leaves. Levels of 12-oxo-phytodienoic acid (OPDA), and SA were substantially higher in WW and SW than in the leaves of the other three phenotypes. Glutathione (GSH) levels were substantially higher in SW than in SG and reactive oxygen species (ROS) levels were significantly lower. Overall, the white mesophyll cells of S. tootsik f. luteoloalbostriata had strong antioxidant properties. SA and OPDA jointly act on the antioxidant pathway to reduce the content of ROS in leaves, thus ensuring the stability of SL.

Open Access

Red radish is a nutritious root vegetable crop that has a short production cycle. Water deficit limits plant productivity, affecting its quantity and quality. Compost amendment offers a potential solution to mitigate water deficit effects. This study assessed the impact of compost manure rates (0%, 50%, 75%, and 100%) and irrigation treatments (40%, 60%, 80%, and 100% of evapotranspiration) on ‘Crimson Giant’ red radish production. Significant differences in growth and quality were observed among these treatments. Compost rates of 75% and 100% improved leaf gas exchange, plant growth (leaf count, fresh weight, dry weight, and area; stem length), root development, total yield (root fresh weight, dry weight, diameter, and length), and root quality (vitamin C and total soluble solid and titratable acidity). The 100% compost and 100% irrigation combination achieved the highest yields. Under water deficit, applying 75% or 100% compost with 80% irrigation conserved 20% of water while maintaining radish output. Overall, compost amendment effectively enhanced red radish growth and production under water deficit.

Open Access
Open Access

A 1975 fig crop reference chapter written by W.B. Storey contains pedigree information involving 30 cultivars from the University of California breeding program and early California. The data were compared with the records from the US Department of Agriculture and statements from two other sources. Graphical representations were used to determine differences among the authors. All data are supplied in this article and supplemental materials. An estimate of correct parentage is presented in the final graph.

Open Access

Fritillaria crassicaulis S. C. Chen is a precious traditional Chinese medicine, but the number of populations has declined rapidly due to overexploitation. An artificial rapid propagation system was established to screen the suitable plant regeneration method and to explore the efficient propagation method, useful for propagation technology or for further research and development of F. crassicaulis. This study selected scale as the experimental material, set Murashige and Skoog (MS) medium as the basic medium, and optimized the types and proportions of plant growth regulator (PGR) suitable for callus induction, bulblet differentiation and proliferation, and plant regeneration by means of single-factor, full-factorial, and L9 (3)4 orthogonal experiments. Results demonstrate that in the experiment with single exogenous PGR, the high concentration of 6-benzylaminopurine (6-BA) was significantly better than kinetin (KT) to induce bulblets, 2, 4-dichloroacetic acid (2, 4-D) had a significant effect on callus induction, and a higher concentration of naphthaleneacetic acid (NAA) was beneficial to the occurrence and growth of bulbs, but the rooting effect promoted by indole butyric acid (IBA) was preferable to that by NAA. In MS medium with 0.5 mg/L 2, 4-D and 1.5 mg/L 6-BA, a large number of yellowish-green compact calli could be induced from the scales with the calli induction frequency at 93.3%, and about 11.4% materials directly differentiated bulblets. In the subsequent orthogonal experiment, after the scales were cultured in MS medium with 2.0 mg/L 6-BA, 0.5 mg/L 2, 4-D, and 0.1 mg/L NAA for 20 days, the small yellow and white globular protuberances formed near the incision, but no callus appeared, and many protuberances appeared on the surface of the scales. After 60 days, the protuberances at the incision developed into bulblets directly, while protuberances on the surface of the scales developed into few bulblets but crowded “leaf spines,” which gradually died and disappeared in the later culture; the proliferation coefficient was ∼6.30 then. Experimental results indicate that the optimal rooting medium for bulblets was 1/2MS medium with 2.0 mg/L IBA and 1.0 mg/L activated carbon (AC), with the rooting rate at 95.6%. This study identifies bulblet regeneration of F. crassicaulis, and an efficient direct organogenesis method was established: regenerated bulblets could be induced from scales in one step, so a large number of regenerated plants with the same genotype could be obtained in a short time.

Open Access

Stemphylium leaf spot, caused by Stemphylium vesicarium, and white rust, caused by Albugo occidentalis, can cause significant losses in spinach production. Management of these foliar diseases of spinach has become increasingly challenging with the development of fungicide resistance in some pathogen populations, high planting density and overhead irrigation used for baby leaf spinach production, and the fact that >60% of fresh market spinach production in the United States is certified organic. To identify spinach cultivars with resistance to Stemphylium leaf spot and white rust, a field trial was performed near Crystal City, TX, USA, in 2021 (79 cultivars), 2022 (87 cultivars), and 2023 (63 cultivars). Each year, the plants were inoculated with S. vesicarium and rated for disease severity. Plants were also rated for white rust severity that resulted from natural infection during the 2021 and the 2022 trials. During each trial, 11% to 27% of the cultivars were identified as resistant to Stemphylium leaf spot, and another 29% to 48% had moderately resistant reactions. In contrast, only 5 of 79 cultivars (6%) in the 2021 trial did not develop symptoms of white rust, and all 87 cultivars evaluated in the 2022 trial had symptoms of white rust. Although there was no significant correlation between mean Stemphylium leaf spot ratings and mean white rust ratings during these trials, the cultivars Colusa, Kodiak, PV-1569, and PV-1664 displayed resistant or moderately resistant responses to both diseases in at least two trials. Therefore, processing and fresh market spinach growers have resistant cultivars from which to select to reduce the economic impacts of Stemphylium leaf spot and white rust.

Open Access

Pepper (Capsicum spp.) is an important solanaceous cash crop in Benin; however, productivity is limited due to several key constraints, especially diseases caused by viruses. We sought to understand farmers’ perceptions of viral diseases, management strategies deployed, and to identify the virus population affecting pepper production in Benin. To assess farmers’ perceptions and management of viral diseases, a survey was carried out in four agroecological zones of Benin. A total of 144 pepper farmers were interviewed using the snowball method. A total of 52 pepper leaf samples with virus-like symptoms were collected and diagnosed by reverse-transcriptase polymerase chain reaction (RT-PCR) or PCR. Pepper production systems varied across agroecological zones (P ≤ 0.001) with a predominance of farms practicing monoculture (82%). The majority of farmers (89%) indicated that pests and diseases were the main constraints to increased production. Cucumber mosaic virus (92% of the total samples), Pepper vein yellow virus (52%), and Pepper veinal mottle virus (50%) were the major viruses detected in pepper fields in Benin. There were both single (29%) and mixed (71%) infections of the viruses, suggesting that mixed infections are common for pepper in Benin, confounding efforts to reduce virus infections. Nearly 100% of the farmers surveyed were not aware of these viral diseases. They also could not directly relate symptoms of virus infection to the presence of aphids, whiteflies, or thrips. Farmers relied primarily on synthetic insecticides (93%) to control virus vectors. Interestingly, some farmers applied commercial (12%) and homemade (17%) biopesticides, with neem-based preparations being the most widely used. A total of 15% of farmers used companion cropping with maize, mint or basil and 43% of farmers used crop rotation as a cultural management practice to control viral disease and vector pressure in pepper fields. The implications of this work include the importance of training farmers and extension agents on diagnosis of viruses and their vectors causing viral diseases. This study provides baseline information for the development of host-resistant cultivars and deployment of integrated pest management strategies for pepper in Benin to reduce farmer losses.

Open Access