rss_2.0Sciendo RSS Feed for Journal of Horticultural Researchhttps://sciendo.com/journal/JOHRhttps://www.sciendo.comhttps://sciendo-parsed.s3.eu-central-1.amazonaws.com/64722590215d2f6c89dbd714/cover-image.jpghttps://sciendo.com/journal/JOHR140216https://sciendo.com/article/10.2478/johr-2025-0002<abstract> <title style='display:none'>Abstract</title> <p>Light quality and intensity markedly influence stomatal activity, a crucial physiological process regulating gas exchange and water loss in higher plants. Stomata dynamically open and close in response to environmental signals, facilitating carbon dioxide uptake for photosynthesis while modulating transpirational water loss. Although red and blue light are well-established regulators of stomatal function, the effect of green light on this process remains comparatively underexplored. In this study, the effects of multiple light wavelengths (430 nm, 530 nm, 560 nm, and 630 nm) and intensities (50, 75, 100, and 400 µmol·m⁻²·s⁻¹) on stomatal responses in lettuce (<italic>Lactuca sativa</italic>) and basil (<italic>Ocimum basilicum</italic>) were systematically evaluated. The results showed that green light (530 nm and 560 nm) effectively maintained stomatal closure at lower intensities, thereby minimizing water loss and preserving tissue freshness during postharvest storage. These findings highlight the potential application of green light to optimize postharvest handling by reducing transpiration and improving shelf life of leafy crops. This evidence provides a foundation for targeted light management strategies aimed at improving the commercial quality and marketability of horticultural produce.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2025-00022025-03-24T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2025-0001<abstract> <title style='display:none'>Abstract</title> <p>Root-knot nematodes contribute to significant yield loss in tomato production, with limited management options available to farmers. The study was carried out to determine the control efficacy of six native <italic>Trichoderma</italic> isolates from Ghanaian soils against root-knot nematodes. Root-knot nematode juveniles (J2) and different <italic>Trichoderma</italic> isolates were extracted from infected roots and soil samples, following standard laboratory protocols. Roots of tomato seedlings were coinoculated with 1000 J2 of root-knot nematodes and 10⁷ spores per gram of soil of individual <italic>Trichoderma</italic> isolates. Plant height, stem girth, and number of leaves were measured on different days after treatment. Root gall severity, egg mass numbers, final nematode population, and biocontrol efficiency of isolates were determined at harvest. Significant differences in root galls, egg masses, final nematode population, root fresh weight, shoot fresh weight, plant height, stem girth, and leaf number were found between <italic>Trichoderma-</italic>treated plants and their control. Three <italic>Trichoderma</italic> isolates, P34-5, OKK3, and Tech10, were highly effective against root-knot nematodes and need further evaluation and potential formulation as biocontrol products against root-knot nematodes attacking tomatoes.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2025-00012025-02-17T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0021<abstract><title style='display:none'>Abstract</title> <p>This study aimed to evaluate the effect of indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA) concentrations (0 ppm, 300 ppm, 500 ppm, 750 ppm, 1000 ppm, and 1500 ppm) on root development and sprouting of <italic>Thymus atlanticus</italic> stem cuttings. The results showed a significant effect of auxin type and concentration on survival rate, rooting percentage, root and shoot length, number of shoots, fresh and dry weight. The most efficient was IBA at 1000 ppm, which resulted in a survival rate of 62%, a rooting percentage of 57%, a shoot length of 7.5 cm, and 3.1 new shoots per cutting. These findings highlight the potential of IBA to improve the propagation of <italic>Thymus atlanticus</italic> using 3–4 cm long shoots, with has important implications for commercial propagation and ecological rehabilitation.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00212024-12-25T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0018<abstract><title style='display:none'>Abstract</title> <p>The essential challenges in practical applications of date palm micropropagation include explant browning, reduced callus growth, low multiplication rate, and frequent tissue contamination. Our study aimed to evaluate the effects of cefotaxime (Cefo) and silver nanoparticles (AgNPs) on microbial contamination removal, callus growth, and shoot regeneration in date palm micropropagation. Cultures were initiated from bud tips of ‘Barhee’ date palm. Murashige and Skoog medium with auxins, cytokinins, and activated charcoal was amended with Cefo (50, 100, and 200 mg·l⁻¹), AgNPs (0.125 and 0.250 mg·l⁻¹), and a combination of both. The medium supplemented with 200 mg·l⁻¹ Cefo and 0.250 mg·l⁻¹ AgNPs resulted in the best callus growth (318 mg). In contrast, 200 Cefo + 0.125 AgNPs resulted in maximum organogenesis and shoot number per jar (83.4% and 14.1 shoots per jar, respectively). These two combinations resulted in contaminant-free cultures. The total amount of phenolic compounds was significantly reduced to 0.79 and 0.57 mg GAE·g⁻¹ DM in shoots cultured in the above media, which was reflected in the low browning rate. The data revealed that the maximum endogenous IAA content of shoots (2.681 μg·g⁻¹ and 2.345 μg·g⁻¹) was obtained in response to 200 mg·l⁻¹ Cefo + 0.250 AgNPs and 200 mg·l⁻¹ Cefo + 0.125 mg·l⁻¹ AgNPs, respectively. Therefore, the optimized compositions established in the present study could be applicable in reducing contamination and helping callus production and multiple shoot regeneration. To our knowledge, this is the first study of the antibacterial and growth-promoting effects of Cefo in combination with AgNPs in <italic>in vitro</italic> cultures of ‘Barhee’ date palm.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00182024-12-25T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0020<abstract><title style='display:none'>Abstract</title> <p>The research aimed to investigate the regenerative capacity of <italic>Cymbidium aloifolium </italic>shoot tips obtained <italic>in vitro</italic>. Shoot-tip explants (&lt; 1–2 mm) of <italic>C</italic>. <italic>aloifolium</italic> were cultured on Mitra medium supplemented with cytokinins and auxins individually and in combinations. The regenerative response, proliferation of regenerants, and subsequent plantlet development were evaluated. Explants (&lt; 1 mm) remained resistant to regeneration, whereas those 1–2 mm responded to the chemical stimulus. Auxins were highly beneficial in initiating the regenerative response and early plantlet development. Protocorms multiplied best on medium containing sucrose at a concentration of 15 g·L^-1.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00202024-12-25T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0019<abstract><title style='display:none'>Abstract</title> <p>In this study, we evaluated the role of salicylic acid in diminishing fungal contamination in <italic>in vitro</italic> cultures of date palm and the effect of salicylic acid on the regeneration of somatic embryos from callus formed on shoot tips. The most prevalent fungi were <italic>Alternaria alternata</italic> (37%), <italic>Fusarium solani</italic> (25%), <italic>Aspergillus fumigatus </italic>(18%), and <italic>Penicillium expansum</italic> (6%). Salicylic acid limited and at higher concentrations retarded mycelial growth using potato dextrose agar. Salicylic acid at concentrations of 1.5 and 2.0 mM added to MS medium with 2iP and NAA significantly increased the embryogenesis rate of calli explants to 64.9% and 56.7%, respectively, compared with the control (12.3%). Salicylic acid also increased plantlet development from embryos by about 27% compared with the control. Salicylic acid caused better shoot and root growth and increased chlorophyll content. The results showed that the addition of salicylic acid at 1.5 mM to the MS medium resulted in a significant increase in the concentrations of IAA and ABA, as well as a decrease in the concentration of IBA in leaves.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00192024-12-25T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0017<abstract> <title style='display:none'>Abstract</title> <p>Low-chilling apple genotypes have become a viable alternative for cultivation in regions with moderate to mild winters due to concerns about the impact of global climate change. Although the cultivation of low-chilling apples has been known since the last century, there is little research on their propagation and cultural operations, which creates an urgent need for structured information collection. This work presents a comprehensive review of agrotechnological practices aimed at successfully cultivating low-chilling apple cultivars in nontraditional, warmer regions in order to regulate apple prices in local markets and reduce the carbon footprint associated with transportation. By providing comprehensive insights into various agro-technological practices and recent advances in low-chilling apple cultivation, this review can serve as a valuable resource for researchers, growers, and practitioners interested in the successful cultivation of apples in nontraditional areas throughout the globe.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00172024-12-11T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0012<abstract> <title style='display:none'>Abstract</title> <p>The apple tree is one of the most widespread fruit crops in the world. As the area of plantings increases and horticulture transitions to intensive technologies, the demand for skilled workers increases. The introduction of mechanization processes can solve this problem at all stages of fruit production. The aim of this study was to investigate the effect of contour pruning and its modification at different times on the growth of ‘Jonaweld’ apple trees grafted onto the dwarf rootstock M.9 T337. As a result of contour pruning, the trunk diameter increased by 61% and the number of shoots by 40%. Contour pruning with manual refinement produced intermediate results between manual and contour pruning. Furthermore, contour pruning produced the shortest shoots, only 22 cm, compared to 29 cm with manual pruning. There was also a general tendency to limit the growth activity of trees due to postponing pruning. The growth of trunk diameter slowed by 25%, the number of shoots decreased by 8%, and their length decreased by 20%. Specific productivity was highest when contouring with postharvest refinement and pruning.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00122024-10-24T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0016<abstract> <title style='display:none'>Abstract</title> <p>The optimization of tissue culture protocols for blueberry propagation is crucial to meet the increasing demand for disease-free planting materials. This study aimed to determine the effects of three auxins (IBA, IAA, and NAA) at different concentrations to enhance root and shoot development of two blueberry cultivars with different abilities to root, ‘Lanmei #1’and ‘Brightwell’. Results showed that NAA at 0.5 mg·L⁻¹ significantly promoted shoot number and length in ‘Lanmei #1’ while ‘Brightwell’ showed a limited response. IAA had a variable impact on both shoot and root parameters, with ‘Lanmei #1’ showing more pronounced positive responses. IBA showed a differential response on root and shoot parameters in both cultivars, with ‘Lanmei #1’ showing a superior response for shoot number, length, root length, and overall plant vigor. Activated carbon had minimal effect on growth parameters across both cultivars. ‘Lanmei #1’ demonstrated a robust response to auxin treatments, suggesting it is more suitable for in vitro rooting. The present results confirm previous data on the different abilities of blueberry genotypes to root and the necessity of optimizing the rooting protocol depending on the cultivar.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00162024-10-18T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0015<abstract> <title style='display:none'>Abstract</title> <p>The ornamental plant <italic>Spathiphyllum wallisii</italic> is becoming increasingly popular worldwide, and tissue culture is regarded as a practical option for its massive production. Following the multiplication phase and successive subcultures for an extended period, some morphological changes in shoots were observed in <italic>Spathiphyllum</italic> explants, primarily a reduction in leaf area. For the first time, we report the application of silver nitrate to enhance <italic>Spathiphyllum</italic> shoot and root quality. The Murashige and Skoog (MS) medium, with 30 g·L⁻¹ of sucrose and 100 mg·L⁻¹ of ascorbic acid, was supplemented with different concentrations of AgNO₃. The addition of AgNO₃ improved shoot development and leaf expansion by increasing their length and width. Specifically, at the 2.0–4.0 mg·L⁻¹ range, silver nitrate successfully induced the highest leaf area (1.7 cm²), while stem elongation was promoted with the application of 3.0 mg·L⁻¹ of AgNO₃. Additionally, optimal leaf numbers of new shoots were observed at 1 mg·L⁻¹. Furthermore, when used at an optimal concentration, AgNO₃ significantly boosted rhizogenesis, increasing the number (9.2 roots), length (5.8 cm), and diameter (1 mm) of roots per explant. After the plantlets were transferred to pots, they acclimatized successfully with a 100% survival rate. This finding underscores the potential of silver nitrate to optimize the growth and rooting of <italic>Spathiphyllum</italic> shoots, paving the way for a more efficient micropropagation process.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00152024-10-18T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0014<abstract> <title style='display:none'>Abstract</title> <p>The experiment was carried out in the Botanical Garden and Plant Physiology Laboratory, Department of Botany, Kurukshetra University (India) to identify the effect of postharvest treatments on qualitative traits of control (untreated) and GA₃ pretreated (100 ppm) corms of ‘White Prosperity’ gladiolus to enhance flower quality and prolong longevity. Different concentrations of sucrose alone and in combinations with citric acid and 8-hydroxyquinoline (8-HQ) [T₀ – control (DDW); T₁ – 8% sucrose; T₂ – sucrose (8%) + citric acid (200 ppm); T₃ – sucrose (8%) + 8-HQ (400 ppm); T₄ – citric acid (200 ppm); T₅ – sucrose (4%); T₆ – sucrose (4%) + citric acid (200 ppm); T₇ – sucrose (4%) + 8-HQ (400 ppm)] were used as postharvest treatments under completely randomized design with ten replicates per treatment. The moisture content and the fresh weight were higher in spikes obtained from GA₃ pretreated corms placed in sucrose (4%) + 8-HQ (400 ppm) solution as postharvest treatment followed by sucrose (4%) + citric acid (200 ppm) in gladiolus. The combination of sucrose (4%) + 8-HQ (400 ppm) followed by sucrose (4%) + citric acid (200 ppm) also demonstrated the best outcomes in terms of improving water uptake and vase life, which increased by ten days. These best preservative treatments are suitable for delaying flower senescence, prolonging the vase life, and enhancing the postharvest quality of gladioli. Further, this method can also help in testing new gladiolus hybrid selections.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00142024-10-04T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0013<abstract> <title style='display:none'>Abstract</title> <p>The disadvantages of practical date palm micropropagation are tissue browning, low callus proliferation rate, low multiplication efficiency, and vitrification. The aim of the study was to determine the effect of ancymidol (Ancy) and phloroglucinol (PG) on the growth and some biochemical components of the ‘Barhee’ date palm cultured <italic>in vitro</italic>. The combination of 0.75 mg·l⁻¹ Ancy and 50 mg·l⁻¹ PG was found to be the most effective in terms of callus regeneration rate (89%) and number of shoots (14.3). A reduction in browning was observed in tissues cultured on media supplemented with 0.75 mg·l⁻¹ Ancy in combination with 25 or 50 mg·l⁻¹ PG. The medium supplemented with 0.75 mg·l⁻¹ Ancy and 50 mg·l⁻¹ PG eliminated shoot vitrification. Effective micropropagation was associated with increased carbohydrate and protein content. In this study, the genetic stability of plants obtained by micropropagation was confirmed by DNA-based RAPD fingerprinting. The results may indicate that the micropropagation protocol used in this study was suitable and applicable to the production of genetically stable date palm plants on a mass scale.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00132024-09-28T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0011<abstract> <title style='display:none'>Abstract</title> <p><italic>Meloidogyne incognita</italic> is a common pest of carrots grown in hot climates. Existing control methods using synthetic nematicides are associated with contamination and intoxication of plants and the production environment. Recent research trends in pest control include investigations on the use of plant materials. In the present study, <italic>Blumea aurita</italic> compost, powder, and essential oil were assessed in comparison with Furadan for mitigating the effects of <italic>M. incognita</italic> on carrot plants. The essential oil was applied at 10, 20, and 30 mg·ml⁻¹, while the compost and powder were applied at 1.0, 2.0, and 3.0 kg·m⁻². The characteristic components of <italic>B. aurita</italic> essential oil were trans-α-bergamotene (18.04%), caryophyllene epoxide (15.01%), eugenol (11.59%), carvacrol (11.02%), geraniol (10.13%), 1-octen-3-ol (7.03%), 1,8-cineole (7.02%), δ-elemene (7.01%), and α-copaene (6.20%). The reproduction of <italic>M. incognita</italic> on carrot roots and the level of <italic>M. incognita</italic> soil infestation were significantly reduced by <italic>B. aurita</italic> compost and essential oil. The effect of <italic>B. aurita</italic> compost was comparable to that of the standard nematicide – Furadan. Therefore, materials derived from <italic>B. aurita</italic> may prove to be an interesting alternative in inhibiting <italic>M. incognita</italic> populations.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00112024-09-10T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0009<abstract> <title style='display:none'>Abstract</title> <p>The postharvest rot fungus, <italic>Lasiodiplodia theobromae,</italic> poses a significant threat to the avocado trade in Ghana as it discounts both the quality and shelf life of freshly harvested avocado fruits. This study evaluated the biological effect of three bioagents, garlic, baking soda, and black pepper, on mitigating posthar-vest rots of avocado fruits caused by <italic>L. theobromae.</italic> Isolates of <italic>L. theobromae</italic> obtained from spoiled fruits were identified using morphological, molecular, and pathogenicity procedures. Eight isolates of <italic>L. theobromae</italic> were similar in morphology and pathogenicity and genetic markers (ITS). The three bioagents, garlic and pepper seed powder, and baking soda, were evaluated <italic>in vitro</italic> using the food poison technique at two concentrations, 10 g and 20 g per 100 ml of water. Garlic at 20 g/100 ml of water completely inhibited mycelium growth, followed with 10 g/l (7.8%), and baking soda at 20 g/l (32.6%). Further studies of these bioagents on fruit are recommended.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00092024-06-29T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0008<abstract> <title style='display:none'>Abstract</title> <p>The present study aims to evaluate nutrient retention in mango, avocado, and tomato dried using freezing, refractance windows, and oven methods. The quality parameters of the dried products were assessed, such as color, water activity, and antioxidant content. Greater color retention was observed for freeze-dried products than for products dried using other methods. All products showed low water activity (&gt;0.4), which prevented microbial growth. Freeze-dried products had the highest content of lycopene and carotenoids. Instead, more flavonoids and phenolics were detected in the refractance window method and then in the oven-dried products. Although freeze-dried products are preferred, the refractance windows method could be a promising drying technology because of its energy savings, easy operations, and low cost.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00082024-06-29T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0006<abstract> <title style='display:none'>Abstract</title> <p>The global threat that the diamondback moth (DBM) (<italic>Plutella xylostella</italic>) poses to <italic>Brassica juncea</italic> creates an urgent need to develop effective mitigation strategies. With promising findings, this study explores the potential of plant-derived antioxidants, particularly <italic>Millettia pachyloba</italic>, in mitigating DBM-induced oxidative stress. Greenhouse experiments conducted using <italic>M. pachyloba</italic> leaf ethanol extract (MPEE) at concentrations of 2, 4, 6, 8, and 10 % (w/v) showed the inhibitory effect of MPEE on DBM damage in <italic>B. juncea</italic>. The comprehensive assessment included the effectiveness of MPEE in reducing oxidative stress markers (malondialdehyde, hydrogen peroxide), augmenting metabolites (flavonoids, phenolics), enhancing anti-oxidant compounds (glutathione, ascorbic acid, total protein), and stimulating key enzymes (su-peroxide dismutase, catalase, and ascorbate peroxidase). The results were compared to controls, in which the plants were treated with water or fipronil. Fipronil and MPEE significantly reduced leaf puncturing and damage, and the impact force increased with MPEE concentration. Both types of protection reduced the content of malondialdehyde and hydrogen peroxide in leaves, stems, and roots. However, a significant increase in the content of flavonoids, phenolic and antioxidant compounds (glutathione, ascorbic acid, and proteins) and enzyme activity (superoxide dismutase, ascorbate peroxidase, and catalase) was observed. The enhancement of metabolites, enzymes, and antioxidants was comparable in plants treated with fipronil and MPEE 10%. This study, with its potential to replace synthetic fipronil with <italic>M. pachyloba</italic> extracts to reduce oxidative stress induced by <italic>Plutella xylostella</italic> on mustard plants, offers a promising solution for protection against this insect.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00062024-06-29T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0007<abstract> <title style='display:none'>Abstract</title> <p>Producing leek seeds without replanting one-year-old plants is cheaper and more practical, but can be risky in climates with cold winters. This research aimed to assess whether accelerating the planting of seedlings and using Fulvohumin fertilizer, containing, among others, humic acids can make such production less risky. Three dates were used for planting leek seedlings: April 10, April 25, and May 10. Fulvohumin was used presowing, foliarly, and both. Both factors significantly improved seed production. The best results were obtained at the earliest planting date, as the plants were strong and best prepared for the generative phase and the frost period. Fulvohumin significantly improved growth and development parameters, mainly when used before sowing and as foliar application. In the best combination, with two applications of fertilizers, the seed yield increased by 39%, compared to the control (without Fulvohumin fertilization), and the seed yield of plants planted on April 10 was 17% higher compared to plants planted on April 25 (considered as standard) and 39% higher than those planted on May 10. Seed yield varied in the three subsequent years of the study, but each year, the planting date and Fulvohumin had a similar effect on seed yield.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00072024-06-24T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0100ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-01002024-06-07T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0005<abstract> <title style='display:none'>Abstract</title> <p>In quantitative reverse transcription polymerase chain reaction (qRT-PCR), normalizing target gene expression using a reference gene is an indispensable step to control the variability of RNA extraction yield, RNA integrity, reverse transcription efficiency, and PCR amplification. In the present study, we identified candidate reference genes with stable expression during grapes’ flowering and berry development stages. Ten genes, including <italic>ACT</italic>, <italic>CYP5</italic>, <italic>RLI</italic>, <italic>TUB</italic>, <italic>UBC</italic>, <italic>UBC17</italic>, <italic>UBC60</italic>, <italic>UFD1</italic>, <italic>VAG</italic>, and <italic>ZNF</italic> with relatively stable expression, were selected based on RNAseq data generated earlier in grape hybrid ‘ARI 516’. The expression of these candidate genes was tested at different stages of flowering and grape berry development. Five different algorithms such as RefFinder, geNorm, NormFinder, BestKeeper, and the comparative ΔCq method were used to test the expression stability of candidate genes. A comprehensive ranking obtained by RefFinder showed that <italic>UBC17</italic>, <italic>RLI</italic>, and <italic>ZNF</italic> were the most stable reference genes during flower and berry development stages. <italic>UBC17</italic>, <italic>RLI</italic>, and <italic>ZNF</italic> were calibrators to normalize the expression of <italic>VvAGL11</italic> as a target gene to validate the worthiness of identified reference genes. The result demonstrated that newly identified reference genes could be successfully used to normalize the expression of the target gene accurately. These reference genes will provide more choices for selecting appropriate reference genes to normalize gene expression in grapes.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00052024-05-24T00:00:00.000+00:00https://sciendo.com/article/10.2478/johr-2024-0004<abstract> <title style='display:none'>Abstract</title> <p>A lucrative and delicious nonclimacteric tropical fruit, rambutan, has disadvantages of inadequate fruiting, low yield, and inferior edibility at farm level that need to be addressed. Moreover, unstable tropical temperatures and humidity threaten poor fruit set and insufficient rambutan yields. Therefore, the study revealed the effectiveness of gibberellic acid (GA₃) on fruit set and retention, fruit size and yield, shelf life, and postharvest properties of rambutan under these atmospheric conditions. GA₃ at concentrations of 50, 100, 200, 300, 400, and 500 ppm, apart from the control (without GA₃), was applied to panicles twice in the early flowering and the early fruiting stages (thirty days after the first spraying). The results showed that maximum fruit set (223.2 per panicle), retention (13.2 per panicle, 5.9%), and yield (714.0 g per panicle) were obtained by GA₃ treatment at 300 ppm. In addition to increasing fruit size (54.1 g) and pulp weight (31.3 g), GA₃ at a dose of 300 ppm significantly reduced seed weight by 27.5% and increased the edible portion by 26.6% compared to the control. Notably, preharvest GA₃ treatment increased TSS content (19.0%), total sugar (4.5%), and shelf life (11.5 days), while it decreased titratable acidity (0.4%) of rambutan. GA₃ doses from 200 to 500 ppm had similar effects in terms of affecting the edible properties and shelf life of rambutan. However, fruit set, retention, and yield exhibited distinct dose-dependent responses, with 300 ppm being the best and 200 ppm consistent with the best, with some differences. Regression analysis showed a skewed curve explaining higher yield and better fruit quality at the medium GA₃ treatment level (250–350 ppm). In comparison, lower (&lt; 200 ppm) and higher (&gt; 400 ppm) doses resulted in worse results in most cases. Therefore, regulated use of GA₃ is necessary to improve rambutan yield and fruit quality.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johr-2024-00042024-05-22T00:00:00.000+00:00en-us-1