Search Results (49)

Okra (Abelmoschus esculentus) is a tropical vegetable with high nutritional and economic value. Rich in fiber, vitamins (C, K, and B9), and minerals (magnesium, potassium, calcium, and iron), it contributes to food security in many tropical regions. Global production is estimated at 11.5 million tons in 2023, 62% of which will come from India. Nigeria, Mali, Sudan, Pakistan, and Côte d’Ivoire are also among the major producers. Given its economic importance, optimizing its growth through controlled methods such as greenhouse cultivation and light-emitting diode (LED) lighting is a strategic challenge. Energy-efficient LED horticultural lighting offers promising prospects, but each plant variety reacts differently depending on the light spectrum, intensity, and duration of exposure (photoperiod). This study evaluated the effects of different LED spectra on okra’s flowering after 30 days of growth using B (blue, 445 nm) and R (red, 660 nm) LED lights and red-blue alternating in a three-day cycle (R3B3) by alternating the photoperiod from 14 to 10 h. Outdoor and greenhouse conditions served as controls. The results show that the R3B3 treatment improves germination in terms of both speed and percentage. However, plant growth (height, stem diameter, and leaf area) remains higher in the control group. R3B3 and red light stimulate leaf and node development. Flowering occurs earlier in the control group (51 days) and later under LED, particularly blue (73 days). Fruit diameter after petal fall was also larger in the control group. These results confirm the sensitivity of okra to photoperiod and light quality, and highlight the potential of spectral and photoperiod manipulation to regulate flowering in controlled-environment agriculture. Full article

Chilling stress inhibits the growth of okra (Abelmoschus esculentus L.), reduces its overall agricultural yield, and deteriorates fruit quality. Therefore, it is crucial to elucidate the mechanism through which okra plants respond to chilling stress. This study investigates the molecular mechanisms of chilling tolerance by comparing the transcriptome and metabolome of chilling-tolerant (Ae182) and chilling-sensitive (Ae171) okra varieties. We found that Ae182 exhibits higher antioxidant enzyme activities, including SOD, POD, CAT, and APX, suggesting it mitigates oxidative stress more effectively than Ae171. Metabolomics analysis revealed that Ae182 produces higher levels of jasmonic acid (JA) and JA-isoleucine (JA-Ile) under chilling stress, potentially activating genes that alleviate oxidative damage. Additionally, integrated analyses identified key transcription factors, such as AP2, BHLH, and MYB, associated with JA and chilling stress. These findings provide candidate genes for further research on chilling resistance in okra. Full article

Background/Objectives: Blepharitis is a condition often caused by Demodex folliculorum infestations, resulting in significant ocular discomfort and surface damage. Current treatments offer only temporary relief and fail to eliminate mites effectively. This study evaluates nano-niclosamide (nano-NCL), a lipophilic nanosuspension designed to enhance solubility and permeability, for targeting Demodex folliculorum. Methods: Nano-NCL was characterized by particle size, zeta potential, transmission electron microscopy, pH measurement, bacterial culture, and HPLC. Viable Demodex mites were collected from patients’ eyelashes and assigned to six treatment groups: DDW, F127, 0.15% nano-NCL, 0.3% nano-NCL, 20% TTO, and Okra. Mite survival was analyzed using Kaplan–Meier curves. The ocular surface safety was assessed via slit-lamp examination, corneal fluorescein staining, and in vivo confocal microscopy. Results: The nano-NCL particles are uniformly rod-shaped, approximately 291 nm in size, and exhibit good stability, remaining suspended in various media for up to 20 days. The formulation has a stable pH of 6 and demonstrated no bacterial growth, indicating sterility and suitability for clinical use. In vitro, both 0.15% (w/v) and 0.30% (w/v) nano-NCL significantly reduced Demodex survival, with mortality rates ranging from 70.6% to 92.3% within 2 h. Safety evaluations showed minimal corneal staining and inflammation. Notably, 0.15% nano-NCL displayed efficacy comparable to that of 20% tea tree oil (TTO) and Okra, which are established anti-Demodex treatments. Conclusions: Nano-NCL, particularly at 0.15%, rapidly eliminates mites while maintaining excellent ocular tolerability, making it a promising treatment for Demodex-related ocular surface diseases. Full article

The conversion of aquatic biomass into biochar offers a sustainable strategy for improving soil fertility and mitigating ecological imbalances caused by its rapid proliferation. In this study, Typha angustifolia, a widely distributed aquatic weed, was utilized for biochar production. Three biochar types (TABC400, TABC500, and TABC600) were synthesized through pyrolysis at 400 °C, 500 °C, and 600 °C temperature. It was hypothesized that Typha angustifolia biochar would positively influence the growth and development of okra (Abelmoschus esculentus L.). The results demonstrate that biochar yield subsequently decreases with increasing pyrolysis temperature, with the highest yield at 400 °C temperature (49.03%), followed by 500 °C (38.02%) and 600 °C temperature (32.01%). However, carbon content 67.01 to 83.12%, higher heating value (17.31 to 27.42 MJ/kg), and mineral contents (K, Mg, P, Ca, Fe, Cu, Zn) increase significantly with higher pyrolysis temperature. However, oxygen, hydrogen, nitrogen, bulk density, moisture contents, and volatile context exhibited an inverse relationship with pyrolysis temperature, highlighting biochar stability and its potential for soil amendment. Among the three synthesized biochar, the 4%TABC600 (600 °C) revealed the most substantial improvement in plant height (110.11 ± 4.12 cm), plant dry biomass (6.12 ± 0.41 gm), and chlorophyll contact (39.34 ± 3.33 SPAD values), whereas the 2% and 6% TABC600 demonstrated significant influence on fruit yield (9.11 ± 2.11 gm) and fruit weight (750.44 ± 7.83 g), and chlorophyll contact (32–38 SPAD values). Based on our results, we can conclude that Typha angustifolia biochar prepared at 600 °C (TABC600) has great potential as a biofertilizer, promoting soil fertility and growth and development of crops, particularly for vegetable cultivation such as okra. Full article

Soil salinization is one of the abiotic stresses that inhibit plant growth and development, which seriously restricts global crop production. WRKY transcription factors play an important role in regulating plant responses to stress such as salt stress. In our previous study, two WRKY family genes from okra, AeWRKY32 and AeWRKY70, were significantly up-regulated and down-regulated, respectively, in response to salt stress. In this study, subcellular localization showed that they were localized to the nucleus. The down-regulation of AeWRKY32 and AeWRKY70 via whole plant virus-induced gene silencing (VIGS) increased and decreased plant sensitivity to salt stress, respectively. Ectopic expression of AeWRKY32 and AeWRKY70 led to promoted and reduced salt tolerance in transgenic Arabidopsis, respectively. There was no significant difference between transgenic plants and wild type (WT) without salt treatment. Salt stress significantly inhibited plant growth. The decrease of chlorophyll content and the increase of anthocyanin content in AeWRKY32-overexpressed transgenic plants were lower than those in the WT, while AeWRKY70-overexpressed plants had the opposite effect. Under salt stress, the AeWRKY70-overexpressed plants had the highest malondialdehyde (MDA) content, followed by the WT, and the lowest in AeWRKY32-overexpressed plants. The hydrogen peroxide (H₂O₂) content and superoxide anion (O₂^•−) generation rate were only slightly increased. Moreover, salt stress significantly increased plant proline content and antioxidant enzyme activities, which was highest in AeWRKY70-overexpressed plants except superoxide dismutase (SOD). Taken together, these results suggest that AeWRKY32 and AeWRKY70 play positive and negative roles in plant in response to salt stress, respectively. Full article

The fall armyworm, Spodoptera frugiperda, is a major migratory polyphagous insect pest of various crops. The essential nutrient and mineral profile of the host plants determines the feeding fitness of herbivorous insects. As a result, the growth and development of insects is affected. To determine the effect of the nutrient and mineral profile of different host plants (maize, castor bean, cotton, cabbage, okra, and sugarcane) on the growth and development of S. frugiperda, biological parameters like larval weight, pupal weight (male/female), and feeding and growth indices were calculated. The proximate compositions such as crude protein, crude fat, crude fibre, and ash and mineral contents of the tested host plants showed significant differences (p < 0.05). The feeding indices on these host plants also differed significantly (p < 0.05). The maximum relative growth rate (RGR), relative consumption rate (RCR), and consumption index (CI) were recorded in S. frugiperda larvae that fed on maize and castor bean leaves. The crude protein, dry matter, and ash contents in maize and castor bean were significantly higher and positively correlated with the RGR and RCR of S. frugiperda larvae. The larval, male and female pupal weights were the maximum in the larvae feeding on the castor bean host plant. These findings provide novel information based on nutritional ecology to develop sustainable integrated pest management strategies using selective crop rotation. Full article

Abelmoschus esculentus L. is a plant of legume origin; it is used in several areas of nutrition, industry and medicine. This study was proposed in order to understand the adaptation mechanisms of the seeds of this species under the effect of NaCl. Germination was monitored by varying the concentrations of NaCl saline solution (100 mM and 150 mM).The physiological parameters were determined by monitoring the capacity and speed of seed germination at a temperature of 25 °C. The monitoring of biometric parameters was carried out as follows: Calculation of the water content of sprouted okra seeds after one week and-evaluation of the radical length carried out by up-to-date measurements of the radical length of germinated seeds for one week. From the results obtained, it was noted that the cumulative rate of germinated seeds is estimated to be from 17.27% to 14.55% under the effect of 100 mM and 150 mM, respectively, as compared to 47.27% for the control seeds. In addition, it was observed that the treatment with 100 mM NaCl causes a decrease in the germination speed (23.58%) and a slight prolongation in time as compared to the control. On the other hand, the treatment with 150 mM induces a remarkable decrease in germination speed (13.96% versus 24.39%) and average time as compared to the control (2.9 days versus 4.1 days). Furthermore, the monitoring of biometric parameters highlights two essential points: the NaCl treatment limits the growth of seed radicals and reduces the water content of okra seeds as compared to the control. In light of these results, it is possible to conclude that treatment with sodium chloride has a detrimental effect on the germination and growth of Abelmoschus esculentus L. seeds. Full article

Okra (Abelmoschus esculentus L.) is a highly nutritious vegetable rich in vitamins, minerals, and bioactive compounds, including polyphenols, offering numerous health benefits. Despite its nutritional value, okra remains underutilized in Europe; however, its cultivation and popularity may rise in the future with increasing awareness of its advantages. In agricultural practices, beneficial soil microorganisms, such as arbuscular mycorrhizal fungi (AMF), Trichoderma spp., Streptomyces spp., and Aureobasidium spp., play crucial roles in promoting plant health, enhancing agricultural productivity together with improved crop nutritional value. This study aimed to investigate the effects of individual and combined inoculation on the polyphenol content of okra fruits, as analyzed by HPLC. Moreover, growth parameters and glutathione-S-transferase enzyme (GST) activities of okra leaves were also estimated. Tested microorganisms significantly increased the yield of okra plants except for A. pullulans strain DSM 14950 applied individually. All microorganisms led to increased GST enzyme activity of leaves, suggesting a general response to biotic impacts, with individual inoculation showing higher enzyme activity globally compared to combined treatments. According to the polyphenol compound analysis, the application of tested microorganisms held various but generally positive effects on it. Only the combined treatment of F. mosseae and Streptomyces strain K61 significantly increased the coumaric acid content, and the application of Aureobasidium strain DSM 14950 had a positive influence on the levels of quercetin and quercetin-3-diglucoside. Our preliminary results show how distinct polyphenolic compound contents can be selectively altered via precise inoculation with different beneficial microorganisms. Full article

Uneven rainfall, in the context of global warming, can cause soil moisture fluctuations (SMFs) that harm crop growth, and it is not yet known whether nitrogen (N) can mitigate the harm caused by a strong SMF. This paper uses okra as a test subject and sets three SMFs of 45–55% FC (W₁), 35–65% FC (W₂), and 25–75% FC (W₃) and three N applications of 0 kg hm⁻² (N₀), 110 kg hm⁻² (N₁), and 330 kg hm⁻² (N₂) to investigate the effects of SMF and N application on the physiological and biochemical aspects of okra. The results demonstrated that okra exhibited the highest values in stem diameter, number of leaves, photosynthesis characteristics, antioxidant enzyme activity, and yield under the N₁ treatment. The average yield in the N₁ treatment was 149.8 g, significantly surpassing the average yields of the N₀ (129.8 g) and N₃ (84.0 g) treatments. Stomatal density, antioxidant enzyme activity, malondialdehyde content, and proline content in okra leaves were highest in the W₃ treatment, indicating that plants experienced stress in the W₃ treatment. However, the agronomic traits and yields of okra in the N₁ treatment were higher than those in the N₀ and N₁ treatments, indicating that the crop damage caused by W₃ could be mitigated by an appropriate amount of N application. The N₁W₁ treatment emerged as the most suitable combination for okra growth in this study, exhibiting the highest stem diameter, leaf count, photosynthetic characteristics, and yield (201.3 g). Notably, this yield was 67.8% higher than the lowest treatment (N2W3), signifying a significant improvement. Full article

Excessive soil salinity is a major stressor inhibiting crops’ growth, development, and yield. Seed germination is a critical stage of crop growth and development, as well as one of the most salt-sensitive stages. Salt stress has a significant inhibitory effect on seed germination. Okra is a nutritious vegetable, but its seed germination percentage (GP) is low, whether under salt stress conditions or suitable conditions. In this study, we used 180 okra accessions and conducted a genome-wide association study (GWAS) on the germination percentage using 20,133,859 single nucleotide polymorphic (SNP) markers under 0 (CK, diluted water), 70 (treatment 1, T1), and 140 mmol/L (treatment 2, T2) NaCl conditions. Using the mixed linear model (MLM) in Efficient Mixed-model Association eXpedated (EMMAX) and Genome-wide Efficient Mixed Model Association (GEMMA) software, 511 SNP loci were significantly associated during germination, of which 167 SNP loci were detected simultaneously by both programs. Among the 167 SNPs, SNP2619493 on chromosome 59 and SNP2692266 on chromosome 44 were detected simultaneously under the CK, T1, and T2 conditions, and were key SNP loci regulating the GP of okra seeds. Linkage disequilibrium block analysis revealed that nsSNP2626294 (C/T) in Ae59G004900 was near SNP2619493, and the amino acid changes caused by nsSNP2626294 led to an increase in the phenotypic values in some okra accessions. There was an nsSNP2688406 (A/G) in Ae44G005470 near SNP2692266, and the amino acid change caused by nsSNP2688406 led to a decrease in phenotypic values in some okra accessions. These results indicate that Ae59G004900 and Ae44G005470 regulate the GP of okra seeds under salt and no-salt stresses. The gene expression analysis further demonstrated these results. The SNP markers and genes that were identified in this study will provide reference for further research on the GP of okra, as well as new genetic markers and candidate genes for cultivating new okra varieties with high GPs under salt and no-salt stress conditions. Full article

A field experiment was conducted on okra (Abelmoschus esculentus L.) for assessing the sustainability of yield with optimum irrigation schedule based on soil moisture depletion. Four irrigation treatments: Irrigation at I₁:20%, I₂:30%, I₃:40% and I₄:50% of soil moisture depletion rate in main plots and three fertilizer treatments: Fertigation at F₁:100%, F₂:80% and F₃:60% of recommended NPK (100:25:40 kg/ha) in subplots were tested. Soil matric potential was recorded continuously using electronic tensiometers. The soil moisture characteristics curve was derived for various soil matric potential value sand the soil water content. The irrigation controller triggered solenoid valves for irrigation when soil moisture depletion reached a prespecified level in each treatment. Soil moisture depletion values were significantly predicted based on a regression model calibrated for each treatment over the crop growing period. The model gave minimum prediction error (PE) for I₁, followed by I₂, I₃ and I₄, respectively. Plant growth and yield parameters were significantly influenced by the soil moisture availability under each treatment. It is recommended that irrigation be scheduled at 20% soil moisture depletion rate together with 100% NPK fertilizer application for attaining sustainable yield of okra (12.3 t/ha), apart from maximum WUE (3.5 kg/m³) and plant growth parameters under semiarid inceptisols. Full article

Considering the rising concern over climate change and the need for local food security, productive blue-green roofs (PBGR) can be an effective solution to mitigate many relevant environmental issues. However, their cost of operation is high because they are intensive, and an economical operation and maintenance approach will render them as more viable alternative. Low-cost sensors with the Internet of Things can provide reliable solutions to the real-time management and distributed monitoring of such roofs through monitoring the plant as well soil conditions. This research assesses the extent to which a low-cost image sensor can be deployed to perform continuous, automated monitoring of a urban rooftop farm as a PBGR and evaluates the thermal performance of the roof for additional crops. An RGB-depth image sensor was used in this study to monitor crop growth. Images collected from weekly scans were processed by segmentation to estimate the plant heights of three crops species. The devised technique performed well for leafy and tall stem plants like okra, and the correlation between the estimated and observed growth characteristics was acceptable. For smaller plants, bright light and shadow considerably influenced the image quality, decreasing the precision. Six other crop species were monitored using a wireless sensor network to investigate how different crop varieties respond in terms of thermal performance. Celery, snow peas, and potato were measured with maximum daily cooling records, while beet and zucchini showed sound cooling effects in terms of mean daily cooling. Full article

Okra is a vegetable crop adapted to summer temperatures, but heat stress has been shown to reduce its growth and productivity. We measured physiological traits of 104 okra genotypes in response to high temperature, augmented by the molecular characterization of selected genotypes to identify parents for crossing. Genotypes were exposed to a short heat shock (45 °C, 4 h) in a controlled environment, followed by the assessment of chlorophyll fluorescence (F_v/F_m, F_v′/F_m′) and stomatal conductance (g_s). DNA was isolated from all genotypes using a modified CTAB method with additional PVP and RNase, and the amplification of 8 polymorphic SSR markers was used to generate a dendrogram. This preliminary screening identified 33 polymorphic genotypes with less than 50% genetic similarity and contrasting F_v′/F_m′ and g_s responses. More detailed physiological measurements (F_v/F_mF_v′/F_m′, g_s, photosynthesis (A), efficiency of the open reaction centre (Φ_PSII), and electrolyte leakage (EL)) were conducted after exposure to 45 °C for 6 h and compared to the control (30 °C). EL did not significantly increase in the heat treatment; in contrast, there were significant genotype and treatment effects observed for fluorescence (F_v/F_m, F_v′/F_m′) and photosynthetic parameters (A, Φ_PSII, g_s). In conclusion, cell membranes in okra remained unaffected after short periods of heat stress, whereas the ranking of differences of measured physiological traits (∆) between control and heat-treated plants (∆F_v′/F_m′, ∆F_v′/F_m′, ∆A, ∆Φ_PSII, ∆g_s) was indicative of genotype sensitivity to heat. Full article

Okra (Abelmoschus esculentus) is an important vegetable that has been indigenized in African countries where it is consumed as a relish. There is still, however, a lack of documented cultivation techniques for better yields. An organic medium-enclosed trough (OMET) system is a growing technique that has been developed to reduce water and nutrient seepage during plant production. The study objectives evaluated the effect of OMET on the growth, yield, and nutritional attributes of okra. A complete randomized block design was established to accommodate the two treatments: OMET and non-OMET, in a micro-plot under field conditions. The stem diameter and plant height were recorded weekly during plant growth, and a clear increasing trend in OMET over non-OMET was observed from week 4 of transplantation. The OMET growing technique significantly increased the stem diameter and plant height by 37 and 48%, respectively. When evaluating the yield attributes, a similar trend was observed, where the OMET system significantly increased the yield attributes of okra as follows: biomass by 50%, the number of branches by 50%, the number of pods per plant by 49%, fresh pod weight by 53%, and pod length by 51%, while there was no significant difference in pod diameter width. Non-essential amino acids compounds, including arginine, serine, glycine, aspartate acid, glutamic acid, alanine, and proline and essential amino acids, including histidine, threonine, methionine, lysine, tyrosine, leucine, phenylalanine, asparagine and glutamine, were highly maintained in OMET compared to non-OMET. OMET enhanced the upregulation of proteins, Ca, Mg, K, Mn, Na, P and Zn elemental nutrients in the disposal of less irrigation water than non-OMET. This growing technique could be recommended for small-scale and commercial farming to improve the okra production of nutrition. Full article

Microorganisms colonize plant roots and exhibit plant growth promotion properties, therefore functioning as biofertilizers. To effectively use plant growth-promoting rhizobacteria, understanding their colonizing behavior and ability to compete with co-existing bacteria is essential. In this study, 12 endophytic bacterial strains belonging to seven genera in four classes with 99–100% homology were isolated from the roots of okra plants (Abelmoschus esculentus L.). Four isolates (Okhm3, Okhm5-4, Okhm10, and Okhm11) were inoculated on okra seeds and their effects on plant growth and colonization with single and mixed inoculations were evaluated. Okra was cultivated using sterilized vermiculite, and the growth parameters and colonization were measured 30 d after seed inoculation. All strains exhibited plant growth promotion traits that could improve okra plant growth in pot culture experiments. Notably, Okhm5-4 and Okhm10 strains (belonging to the Ensifer and Pseudomonas genera) revealed the highest growth-promoting effects on okra plants. Both strains were detected in the endosphere and rhizosphere of okra plants. Okhm10 and Okhm5-4, with lower colonization than Okhm3, showed better growth than Okhm3. Therefore, the colonization potential does not determine the growth-promoting effects. While Okhm3 populations remained stable in both inoculation conditions, the population level of other strains decreased in the mixed inoculation. This study showed bacterial endophytes isolated from Okra can be exploited as bio-fertilizers for sustainable agriculture systems. Full article