Improving the productivity of sweet pepper (Capsicum annuum) is essential to meeting the increasing global demand. This can be partially accomplished by investigating and determining high-yield traits, thereby enabling the selection or breeding of high-yield plants. Therefore, this study aimed to determine the high-yield traits of sweet pepper by analyzing its yield components. We analyzed yield components of commercially available cultivars (red and yellow) that were hydroponically grown in a greenhouse (e.g., total fruit fresh weight, fruit dry weight, fruit dry matter content, total dry matter production, and light-use efficiency) using Pearson’s correlation coefficient (r). Our results showed the following: the total fruit fresh weight was positively and negatively correlated with the fruit dry weight (r = 0.83; P < 0.001) and fruit dry matter content (r = –0.70; P < 0.001), respectively; the fruit dry weight was positively correlated with the total dry matter production (r = 0.50; P < 0.01), and the total dry matter production was positively correlated with the light-use efficiency (r = 0.93; P < 0.001); and the cultivars with the high total fruit fresh weight were characterized by the notably low fruit dry matter content and high light-use efficiency (e.g., ‘Gialte’). In conclusion, high-yielding sweet peppers are characterized by a low fruit dry matter content and high light-use efficiency.
Macrophomina phaseolina, the causal agent of charcoal rot, is one of the most destructive soil-borne pathogens that affect the global strawberry industry. Resistant cultivars are critical for ensuring the profitability of strawberry production without the protection historically provided by methyl bromide. Previously, three loci, namely, FaRMp1, FaRMp2, and FaRMp3, associated with quantitative resistance to Macrophomina phaseolina have been identified and validated across diverse populations and environments. Among those, the locus with the largest effect, FaRMp3, was initially detected in crosses with an exotic Fragaria ×ananassa selection. We introgressed the favorable FaRMp3 allele into elite germplasm in the University of Florida strawberry breeding program already segregating for FaRMp1 and FaRMp2 and confirmed its phenotypic effects across various genetic backgrounds. Subsequently, we developed a high-throughput genotyping assay to facilitate the transfer and selection of FaRMp3 in breeding populations via marker-assisted selection. Given that three quantitative trait loci (QTL) contribute to partial resistance to Macrophomina phaseolina, stacking them within a single genotype presents a potential strategy for enhancing resistance. We screened 564 individuals that segregate for favorable alleles at all three QTL to assess their effects singly and in combination across multiple genetic backgrounds and production seasons. Inoculated field trials revealed that the three QTL cumulatively enhanced resistance levels, and that two-way QTL combinations including FaRMp3 provide increased protection against the pathogen. Pyramiding all three loci achieved the strongest resistance and could provide substantial economic value to the strawberry industry.
Strawberry fruits are popular among consumers because of their unique flavor and reported health benefits. However, microbial growth and oxidative stress that occur in postharvest storage cause strawberry fruits to have a relatively short postharvest life, which reduces consumer acceptance. This study aimed to evaluate the effects of exogenous melatonin application on the enzymatic activity and postharvest quality of strawberry fruits that are stored at 4 ± 0.5 °C. A total of 288 fruits with four replicates for each of the three treatments (control, 200 μM melatonin, and 500 μM melatonin) were used. Several quality metrics were regularly assessed at 3-day intervals during the 18-day storage trials. The results suggested that the exogenous melatonin application significantly increased the activity of antioxidant enzymes at the physiological level, including catalase, ascorbate peroxidase, superoxide dismutase, and peroxidase which led to reductions in weight loss, the decay incidence, and the malondialdehyde level. The use of melatonin successfully delayed changes in the soluble solids concentration, ascorbic acid, titratable acidity, and fruit firmness. The results indicated that applying 500 μM melatonin to strawberries would be a useful strategy for increasing their shelf life.
The western portion of the Pacific Northwest is known for being dry in the summer and cool and humid in the other months. Tall fescue is valued for its drought and heat tolerance, making it a desirable choice in regions where water is scarce and often restricted by legislation during periods of drought in the summer. However, cool and humid climates make it challenging to manage tall fescue in the winter because unacceptable quality is often observed due to low-temperature diseases and thinning in turf. A field trial was initiated in Autumn 2020 in Corvallis, OR, USA to assess the effects of mowing height as well as fertility timing and rate on tall fescue performance. Two mowing heights of 5.1 and 7.6 cm, four seasonal fertility timings, and three levels of annual N rates of 98, 196, and 294 kg·ha−1·yr−1 were evaluated using a 2 × 4 × 3 factorial experiment in a strip-plot design. Quantitative data of percent green cover and normalized difference vegetation index (NDVI) suggest that autumn fertilization is needed in cool, humid areas where tall fescue is actively growing in the winter months. The annual fertilization rate of 294 kg·ha−1·yr−1 N produced higher green turf cover and NDVI, compared with 98 or 196 kg·ha−1·yr−1 N. Furthermore, divergent effects of mowing heights were observed during winter compared with other months, suggesting that tall fescue could be mowed lower at 5.1 cm during cool, humid winter months and higher at 7.6 cm in other seasons for better overall turfgrass growth and less winter disease and thinning. Our research provides practical cultural practices for managing tall fescue turf in the Pacific Northwest or similar climates.
To promote sustainable cultivation and soil health in agriculture, urgent strategies are needed to address the challenges posed by continuous cropping for high-quality pepper production. This study investigated the impact of oats incorporation and biochar amendment in a 12-year continuous pepper cropping system. Compared with the pepper monoculture system (CK), the combination treatment of intercropping with oats and biochar amendment (T1) significantly increased the soluble solids content by 3.13% and the β-carotene content by 8.83-fold in pepper fruits (P < 0.05). The soil pH under intercropping with oats or biochar modification was comparable to that of the CK. Notably, lower soil bacterial operational taxonomic units were observed under this treatment, and soil bacterial diversity decreased consistently with pepper development, regardless of the cultivation system. In contrast, fungal diversity exhibited fluctuations under the companion oat/biochar condition, with fungal community patterns modulated throughout the pepper development process (P < 0.05). Dominant microbes such as Sphingomonas, Pseudomonas, Chrysosporium, Mortierella, and Cladosporium were identified in continuous cropping pepper soils. Kyoto Encyclopedia of Genes and Genomes metabolic profiling revealed significant effects of the cultivation type on the metabolic pathways of functional genes in soil microbial communities. Overall, the practice of planting oats and using biochar in the soils of continuously cropped pepper fields is feasible and sustains the pepper industry as an agroecosystem.
Denphal-type Dendrobium is the famous cut and potted flower in the world, and most cultivated in tropical and subtropical regions. However, it often suffers from cold in winter in subtropical regions. To verify the physiological response of Denphal-type Dendrobium under low temperature in this study, the mature and young plantlets of Dendrobium Udomsri Beauty were treated under 15, 10, and 5 °C, respectively. And then the electrical conductivity (EC), soluble protein, soluble sugar, free proline, malondialdehyde (MDA), chlorophyll content, and the rate of defoliation after regrowth were measured. The results showed that both mature plant and young seedlings of Dendrobium Udomsri Beauty, the EC, soluble protein, soluble sugar, free proline, MDA content, and defoliation rate were increased with the decrease of treatment temperature and the extension of treatment times. The content of chlorophyll decreased gradually with the decrease of treatment temperature and the extension of treatment times. The correlation analysis showed that soluble sugar, free proline, MDA, chlorophyll content, and defoliation rate were significantly correlated with the semi-lethal temperature. It is indicated that the content of free proline, MDA, chlorophyll, and defoliation rate could be used as the effective indexes for the comprehensive assessment of cold tolerance of Dendrobium Udomsri Beauty.