SPAD Units Research Articles

Contrasting Alleles of OsNRT1.1b Fostering Potential in Improving Nitrogen Use Efficiency in Rice.

Nitrogen use efficiency (NUE) is important for the growth and development of rice and is significant in reducing the costs of rice production. OsNRT1.1b is involved in nitrate assimilation, and the alleles at position 21,759,092 on chromosome 10 clearly separate indica (Pathum Thani 1 (PTT1) and Homcholasit (HCS)) and japonica (Azucena and Leum Pua (LP)) rice varieties. Rice morphological and physiological traits were collected at three nitrogen levels (N0 = 0 kg ha-1, N7 = 43.75 kg ha-1, and N14 = 87.5 kg ha-1). Leaf and tiller numbers in PTT1 and HCS at N7 and N14 were two to three times higher than those at N0. At harvest, the biomass yield in PTT1 was the highest, while the total grain number in HCS was the maximum. The leaf widths and total chlorophyll contents (SPAD units) of Azucena and LP increased with nitrogen application as well as photosynthetic pigment parameters; for example, plant senescence reflectance indices (PSRIs), structure-insensitive pigment indices (SIPIs), and modified chlorophyll absorption ratio indices (MCARIs) were highly related in the japonica varieties. PTT1 and HCS, both carrying the A allele at OsNRT1.1b, had better NUE than Azucena and LP with the G allele. HCS, overall, had better NUE than PTT1. The translation to grain yield of assimilates was remarkable in PTT1 and HCS compared with Azucena and LP. In addition, HCS converted biomass for a 75% higher yield than PTT1. The ability of HCS to produce high yields was achieved even at N7 nitrogen fertilization, manifesting efficient use of nitrogen.

Effect of Cutting Type, Potting Media, and Irrigation Frequency on the Success of Vegetative Propagation of Iriweriya (<em>Plectranthus Zeylanicus</em> Forssk)

Plectranthus zeylanicus is an indigenous, multi-functional herb used in traditional medicine. Due to over-exploitation from the natural habitats, the species is on the verge of extinction. Therefore, commercial cultivation of the species is needed to satisfy the rising demand while protecting its genetic base. The current study was designed with three trials to identify the most suitable cutting type, potting media, and irrigation schedule for P. zeylanicus. Four distinct cutting types (tip cutting, triple nodal cutting, double nodal cutting and single nodal cutting), five different potting mixtures (topsoil: sand: compost-1:1:1, topsoil: sand: compost-1:2:1, topsoil: sand: compost-1:1:2, topsoil: compost -1:1, topsoil: compost-1:2) and four different irrigation schedules (daily watering to field capacity level, daily watering to half of the field capacity level, every other day to the field capacity level, every other day to half of the field capacity level) were used in Completely Randomized Design with ten replicates. Survival percentage (%), number of leaves, the height of the plant (cm), average length of roots (cm), average leaf area (mm2), and chlorophyll content (SPAD Unit) were measured as growth parameters. Data were analyzed using SAS software with a 5% significance levels. Highest survival percentage (95%), highest average root length (26.8 cm), average leaf area (80.5 mm2) and a higher chlorophyll content (31.1 SPAD Unit) were recorded from tip cuttings of P. zeylanicus. Furthermore, the topsoil: sand: compost-1:1:1 combination showed a higher survival percentage (90%), number of leaves (3), highest average plant height (43.9cm) and average root length (20.2 cm) with significantly (P<0.05) higher average leaf area (52.3 mm2) and chlorophyll content (31.07 SPAD Unit). Daily watering to the field capacity showed a higher survival percentage (90%), significantly higher (P<0.05) number of leaves (3.7), plant height (51.6 cm), higher root length (25.5 cm), the highest average leaf area (80.0 mm2) and chlorophyll content (32.7 SPAD Unit). Therefore, tip-cutting planted in topsoil: sand: compost-1:1:1 media can be recommended for successful propagation of P. zeylanicus.

Light Quality Influence on Growth Performance and Physiological Activity of Coleus Cultivars

This study investigates the influence of different light qualities, including red, green, blue, purple, and white lights, on the growth, physiological activity, and ornamental characteristics of two Coleus cultivars. Emphasizing the importance of leveraging phenotypic plasticity in plants within controlled environments, using light quality is a practice prevalent in the ornamental industry. The research explores the varied responses of two Coleus cultivars to distinct light spectra. The key findings reveal the efficacy of red light in enhancing shoot and leaf parameters in C. ‘Highway Ruby’, while red and green light exhibit comparable effects on shoot width and leaf dimensions in C. ‘Wizard Jade’. White light-emitting diodes (LEDs), particularly with color temperatures of 4100 K and 6500 K, promote root length growth in the respective cultivars. Moreover, chlorophyll content and remote sensing vegetation indices, including chlorophyll content (SPAD units), the normalized difference vegetation index (NDVI), the modified chlorophyll absorption ratio index (MCARI), and the photochemical reflectance index (PRI), along with the chlorophyll fluorescence, were significantly affected by light qualities, with distinct responses observed between the cultivars. In summary, this study highlights the transformative potential of LED technology in optimizing the growth and ornamental quality of foliage plants like Coleus, setting a benchmark for light quality conditions. By leveraging LED technology, producers and nursery growers access enhanced energy efficiency and unparalleled versatility, paving the way for significant advancements in plant growth, color intensity, and two-tone variations. This presents a distinct advantage over conventional production methods, offering a more sustainable and economically viable approach for increased plant reproduction and growth development. Likewise, the specific benefits derived from this study provide invaluable insights, enabling growers to strategically develop ornamental varieties that thrive under optimized light conditions and exhibit heightened visual appeal and market desirability.

Effects of growing media, and cultivar on developments and quality of mango rootstock.

In a successful mango plant establishment, the choice of a strong and healthy rootstock is crucial for subsequent propagation. An experiment was conducted during the 2023 mango seedling growing season at the Sokoine University of Agriculture horticultural sections in Morogoro, Tanzania. The study aimed to evaluate the influence of different growing media and cultivars on the growth and development of quality-certified mango rootstock plants. Ripe local mango fruits were collected from neighbouring farms and sown in polyethylene bags containing a mixture of forest soil, sand, farmyard manure, and sawdust. The experiment followed a randomized complete block design with three replications. Data collected included days to 50% germination, seedling mortality, seedling height, stem girth, and chlorophyll content (measured using the SPAD Unit). Results indicated that using sindano cultivars as rootstock significantly reduced days to germination and increased germination percentage (89.5%) while minimizing seedling mortality (2). Additionally, forest soil contributed to maximum seedling height (43.95 cm), stem diameter (0.52 cm), and chlorophyll content (40.05). The interaction between cultivar and growing media significantly influenced various mango seedling growth parameters. Bongwa cultivars planted in growing media composed of forest soil alone or combined with farmyard manure and sand produced high-quality, certifiable mango rootstock plants.

Cultivar effect on proximal optical sensor measurements and estimation of leaf N content in muskmelon and sweet pepper

In intensive vegetable crops, there is a requirement for monitoring tools that assess crop nitrogen (N) status to reduce N use and the potential for nitrate (NO3-) leaching loss. Monitoring with proximal optical sensors can regularly provide information to vegetable growers to assist with optimal crop N management. Reference values for proximal optical sensor measurements that indicate crop N sufficiency or deficiency are increasingly available in the literature. Available values are species specific; however, their use may be problematic if proximal optical sensor measurements are affected by cultivar. Little is known on whether differences between cultivars, within a species, affect optical sensor measurements and their relationships with crop N status, particularly in vegetable crops. This study evaluated the effect of cultivar on a) measurements with the SPAD-502 chlorophyll meter, Normalized Difference Vegetation Index (NDVI) measured with the Crop Circle ACS 470 canopy reflectance sensor, and Nitrogen Balance Index (NBI-R) measured with the Multiplex fluorimeter, and b) the relationships of these measurements with leaf N content. The study was conducted with four cultivars of muskmelon (Tezac, Bosito, Magiar and Jacobo) and three of sweet pepper (Melchor, Machado and CLX PLRJ 731). In both muskmelon and sweet pepper, there were significant differences between cultivars in SPAD and in NBI-R. The range of differences between the cultivars was 2.2−9.7 and 0.6−2.8 SPAD units in muskmelon and sweet pepper, respectively, and 0−0.16 and 0.020.08 NBI-R units in muskmelon and sweet pepper, respectively. Significant differences between cultivars in the NDVI were only obtained in muskmelon; the range of differences between the four cultivars was 0.01–0.04 NDVI units. The relatively large cultivar effect with SPAD and NBI-R values with muskmelon may limit the use of reference values in this species. For avoiding cultivar effects in the two species evaluated, NDVI is preferrable to SPAD and NBI-R. In general, the slopes and intercepts of linear relationships between optical sensor measurements and leaf N content, for each cultivar of each species, were not significantly different to the slope and intercept of the relationship calculated with pooled data of all cultivars of each species. This indicated that the sensitivity of optical sensors to assess leaf N content was similar between cultivars of each species.

Pengaruh Kompos Ampas Tebu terhadap Pertumbuhan dan Hasil Kacang Panjang pada Tanah Alluvial

This study aims to determine the effect of bagasse compost on growth and yield of beans on alluvial soil. This study uses a randomized block designconsisting of 5 treatment, and repeated 5 times, each replication consisted of 5 samples. Those treatments include, k0 without bagasse compost, k1 = 10 tonnes/ha, equivalent to 4.2 kg/plot, k2 = 20 tonnes/ha, equivalent to 8.4 kg/plot, k3 30 tons/ha, equivalent to 12.6 kg/plot, k4 = 40 tonnes/ha, equivalent to 16.8 kg/plot. Variables observed include green level of leaf (SPAD unit), leaf area (cm2), dry weight of the upper part of the plant (g), root volume (cm3), root dry weight (cm3), The number of pods per plant (fruit), length of pods ( cm) and weight of pods per plant (g). Results showed significant effect on the variable observation pod length and pod weight plant however not real effect on the variable observation root volume, root dryweight, leaf area, leaf chlorophyll, and plant dry weightand number of pods.

Effect of organic substrates on growth, yield, and quality of spinach (Spinacia oleracea L.)

The experiment was conducted on organic substrates to determine the efficiency of reusing waste on spinach growth, yield, quality, and economic efficiency. The result showed treatment 2 (the mix of coffee grounds, cow manure, abalone mushroom residue, and rice husk ash) and treatment 6 (coffee grounds, cow manure, abalone mushroom residue, rice husk ash, and soil) were the best results in 9 treatments. Analysis of nutrition showed that these substrates had total N > 0.11%, P205 > 0.22%, and K2O > 7.39%. Treatment 2 had 25.0 cm of tree height and 29.1 leaves/tree. Leaf length, leaf width (23.8 cm - 8.3 cm), canopy diameter (23.9 cm), chlorophyll 39,6 SPAD Units, root length 14.3 cm, and stem diameter 0.8 cm. The average tree weight and theoretical yield had the highest (76.0 g-2.50 tons/1000 m2). The dry matter percentage was recorded at 12.9%. Treatment 6 was the treatment with the highest Vitamin C content (0.12%). The results of profit, capital efficiency, and marginal income index of treatment two were recorded (45.3 million VND/1000 m2-2.2 - 21.6). The formula, including coffee grounds, cow manure, abalone mushroom residue, and rice husk ash, was the best prospect for application in production practices.

Nickel uptake in leafy greens from contaminated soil: an investigation into phytoavailability and health risk assessment using in vitro digestion model.

Nickel (Ni) is a toxic metal that not only pollutes the environment but also causes harmful impacts on plant growth and human health. Therefore, it is crucial to assess the relationship between the phytoavailability of Ni in soil and its accumulation in edible and non-edible parts of vegetables. A pot experiment was conducted to investigate Ni uptake in three different leafy vegetables, spinach (Spinacia oleracea L.), lettuce (Lactuca sativa L.), and fenugreek (Trigonella foenum-graecum L.), grown in soil artificially contaminated with Ni at three different treatment levels (100mgkg-1, 200mgkg-1, and 300mgkg-1). The potential dietary toxicity of these vegetables in humans was examined by using an in vitro digestion model. The lowest and highest chlorophyll contents were detected in lettuce at 300mgkg-1 of Ni concentration and in control plants of spinach. Their values were 34.16 ± 3.01 (SPAD unit) and 53 ± 3.7673 (SPAD unit), respectively. Among the three vegetables, lettuce and spinach at 300mgkg-1 exhibited the highest accumulation of Ni, with 43mgkg-1 in edible parts and 182mgkg-1 in non-edible parts. Furthermore, health risk index (HRI) values were found to be > 1 for lettuce and fenugreek at Ni concentrations of 200 and 300mgkg-1 for both children and adults. The average bioaccessibility of Ni in lettuce, fenugreek, and spinach during the gastrointestinal phase was 32-23%, 24-10%, and 45-37%, respectively, at a Ni concentration of 300mgkg-1. All three vegetables grown on Ni-contaminated soil may potentially contribute to food chain toxicity. The HRI values being > 1 suggest that these vegetables are unsafe for consumption. Monitoring of Ni concentration in leafy vegetables is essential to minimize human health risks associated with food chain contamination.

Effectiveness of Bacillus subtilis ANT01 and Rhizobium sp. 11B on the control of fusarium wilt in pineapple (Ananas comosus).

Pineapple (Ananas comosus) is commonly infected by Fusarium oxysporum, causal agent of the fusarium wilt disease. Conventionally, growers use synthetic fungicides to control the disease, which lead to environmental pollution, hazardous effects on non-target organisms and risks on human health. The aim of this work was to assess the effectiveness of Bacillus subtilis ANT01 and Rhizobium sp. 11B to control fusarium wilt on pineapple plants. Four treatments derived from a complete factorial design were tested under field conditions. Treatments composed of B. subtilis ANT01 and the combination B. subtilis ANT01-Rhizobium sp. 11B decreased disease severity by 94.4% and 86.1%, respectively. On the other hand, the treatment prepared with Rhizobium sp. 11B alone showed a reduction of 75.0%. Size of leaves and nutritional condition (SPAD units) of the biocontrol agents-treated plants showed no statistical differences. Moreover, B. subtilis ANT01 decreased by 46% the initial soil population of F. oxysporum, while Rhizobium sp. 11B, B. subtilis ANT01 plus Rhizobium sp. 11B and control, showed a population reduction of 12.5%, 24.2% and 23.0%, respectively. These results make evident the potential of B. subtilis ANT01 as biocontrol agent of the pathogen under field conditions.

Effect of levels of water stress on some physiological and chemical traits of wheat cultivars (Triticum aestivum L.)

A field experiment was carried out at the second agricultural experiment station of the College of Agriculture - Al-Muthanna University during the agricultural season of 2022-2023. The objective of the study was to investigate the physiological and chemical responses of different bread wheat varieties to incomplete irrigation. The experiment was conducted utilising the randomised complete block design (RCBD) employing the split plot method, with three replications. The primary factors investigated in this study were related to irrigation deficiencies, which were represented by four different stages: D1 (control), D2 (tillering stage), D3 (elongation stage), and D4 (booting stage). The secondary factors examined in this research were different cultivars, denoted as V1 (Mawadah), V2 (Bohuth 22), V3 (Baraka), and V4 (Ibaa 99). The statistical analysis revealed significant variations among the stages of water stress. The D2 treatment exhibited the highest proline content at 41.692 mg per 100g, while the D4 treatment demonstrated the greatest thickness of vascular bundles in the roots at 201.23 μm. Regarding the cultivars under investigation, it was observed that the Baraka variety exhibited a higher chlorophyll content (54.24 SPAD units). In contrast, the Bohooth22 cultivar displayed a larger diameter of the vascular bundle in the roots (209.78 μm). Additionally, the Mawada variety demonstrated a greater thickness of the leaf vascular bundles (102.38 μm), while the cultivar IPA99 exhibited a higher content of Proline (35.481 mg per 100g). In terms of interference, treatment D3V1 exhibited a higher proline content of 48.607 mg/100g, indicating its superiority. The results of histological analysis showed the superiority of the combination D2V1 in the diameter of the vascular bundles of the roots (247.33) micrometers, and the occurrence of rupture and damage in the cells of the basal tissue of the root tissue in (D2V1, D3V1, D3V2) and in (D2V1, D2V2, D3V2), in addition to the occurrence of rupture and damage in the upper and lower epidermal cells in the tissue of its leaves, while the combination D2V3 wrinkled and damaged mesophyll cells, and excelled in the thickness of the leaf vascular bundles (142.40) µm, as well as showed that detachment and rupture of the upper epidermis from the mesophyll occurred in D2V4. The results of histological cutting of root cells showed that bundle damage appeared in the root tissue of combination D3V3. Also, fracture and separation occurred in the region of the vascular bundle from the underlying tissue, and some wood vessels were also damaged in the root tissue of the treatment D4V1, and in D4V3 there was a rupture in the lower epidermis of the leaf tissue, and a break in the cells of the cortex and epidermis of the root tissue, while in D4V4, damage was observed in the bundle and cells of the cortex, in addition to the occurrence of a tear in the lower epidermis of the leaves.

Effect of Spraying Nano-Fertilizer (Loenergy Plus) and Hibiscus Extract on the Vegetative Growth Characteristics of the Seedling of Sour Orange Citrus aurantium L.

The experiment was carried out from the middle of March until the end of June in the greenhouse belonging to the Department of Horticulture and Landscape Engineering, the College of Agriculture, and the University of Karbala. To investigate the impact of spraying hibiscus extract and Nano-fertilizer (Loenergy Plus) on the vegetative growth traits of the seedling of the orange starting in 2022. The experiment was set up as a randomized complete block design (RCBD) with two factors: with Nano-fertilizer (Loenergy Plus) and hibiscus extract, each in three concentrations, and three replications, each with 18 seedlings and two seedlings each. Following the completion of the experiment, measurements were obtained, the outcomes were evaluated using the statistical design employed, and the averages were compared using the least significant difference test at the level of probability 0.05. The most significant findings were those of the Nano-fertilizer (Loenergy Plus) treatment, which at a concentration of 1.5 ml L-1 was significantly better than other concentrations in all growth characteristics studied (seedling height rate (cm), stem diameter rate (mm), average number of leaves (leaf /seedling), leaf area (cm2), average leaf chlorophyll content (SPAD unit), and shoot dry weight). Most of the growth characteristics that were examined (seedling height rate (cm), stem diameter rate (mm), average number of leaves (leaf/seedling), leaf area (cm2), rate of leaf chlorophyll content (SPAD unit), and shoot dry weight) were significantly improved by the application of hibiscus extract at an 8 g L-1 concentration. While the binary interaction between the two experimental factors (average seedling height (cm), average stem diameter (mm), average leaf chlorophyll content in leaves (SPAD unit), and shoot dry weight) had no significant effect, there was a significant effect of the bilateral interaction between the two experimental factors on the number of leaves (leaves / seedlings) and the leaf area (cm2).

Effect of Adding Chelated Zinc and Vermicompost on Some Indicators of Maize Growth

A field experiment was conducted for the fall season 2022 to grow a crop of yellow corn, zea mzys, class F1, in the Kala Agriculture field of the University of Babylon, in silt clay. The study included an investigation of the effect of adding chelated zinc and Vermicompost and the interaction between them on the growth indicators of maize, Where it included three levels of chelated zinc fertilizer (0, 5, 10) kg.H-1 and symbolized by symbols (Zn0, Zn1, Zn2) respectively for the first factor, while the second factor was the addition of Vermicompost with three levels (0, 10, 20) ton.H-1 and symbolized by the symbols (F0, F1, F2), respectively, and thus the number of transactions became 9 by 3 replications, so the number of experimental units became 27 experimental units. The experiment was carried out according to the RCBD random sectors design. The addition of chelated zinc to the Zn2 treatment gave the highest increase in the vegetative growth characteristics of plant height, chlorophyll index, leaf area, and dry weight of the vegetative total, as the values reached 189.60 cm, 53.92 Spad unit, 56.53 dm2, and 4.86 tons H-1 for each respectively. The addition of Vermicompost to treatment F2 gave the highest increase in vegetative growth indicators for each of the plant height 186.39 cm, chlorophyll index 50.75 spad unit, leaf area 52.87 dm2, and dry weight of the vegetative total 4.88 tons H-1. The dual interaction of chelated zinc and Vermicompost for Zn2F2 treatment gave the highest increase in the growth indicators of yellow corn represented by plant height, chlorophyll index, leaf area, shoot dry weight.

Inducing Resistance Against Seed Rot and Damping-off Disease Infecting Bell Pepper Using Some Antioxidants and its Reflection on Seedling Protection Under Greenhouse Conditions

A greenhouse experiment was performed to assess the efficacy of some bio-control agents and glutathione to induce resistance in pepper plants against damping off disease caused by the fungus Rhizoctoniasolani. The fungus Trichodermaviride was highly efficient in inhabiting R.solani in growth medium when it scored 1.33, the highest antagonistic ability. The bacterium Azospirillum brasilensecould inhibit the pathogenic fungus on PDA growth medium by 100% at 10-5 concentration. Glutathione and Beltanol pesticide control scored 100% growth inhibition at 3000 and 2000 mg/Lm, respectively. Greenhouse experiment showed T.viride, A. brasilense and glutathione (G) combination treatment decreased infectivity and disease severity to 0.00 and 0. 00%, respectively, compared to 56.67 and 55.00% for R.solani only treatment. While (G + R. solani ), (T. viride +R.solani), (T. viride + G +R.solani) and (A. brasilense + G +R.solani) scored 3.33, 33.33, 10.00 and 10.00% infectivity and 1.67, 1.67. 6.67 and 8.33 % disease severity, respectively. Besides, the combination (T. viride+ A. brasilense + G) scored the highest plant height, dry and wet weights and total chlorophyll content, which were 100.00 cm, 87.33 and 32.08 gm/plant and 60.00 SPAD unit, respectively. Keywords: Seed Rot, Damping off Disease, Bell Pepper, Greenhouse Conditions

Some Agronomical and Physiological Characteristics of Sang Yod Phatthalung Rice from In Vitro Regenerated Plant After Transfer to Clay Soil in Field Conditions

Sang Yod Phatthalung rice is indica rice and grown as Geographical Indications (GI) in Patthalung province. Its dark red color seed contains high antioxidant activity that helps reduction in the risk of some chronic diseases such as diabetes, cancer, and cardiovascular diseases. So far, yield per planting area of this rice is still low. Thus, application of PGRs might play an alternative role in agronomical and physiological characteristics leading to improving yield of this rice. First, shoot tips of Sang Yod Phatthalung rice were cultured to induce multiple shoots and root on liquified PGR-free oil palm culture medium (OPCM) with different concentrations of 6-benzyladenine (BA) (0, 0.5, 1, 1.5 mg/L) alone or in combination with 1-naphthaleneacetic acid (NAA) (0 and 0.5 mg/L). Complete plants were acclimatized to field condition at Phatthalung Rice Research Station (PRRS). After acclimatization for 120 and 140 days, some agronomical and physiological characteristics of rice plant obtained from different PGR containing OPCM were statistically compared. A 2×4 factorial design in RCBD with 4 replication was performed. The results were clearly demonstrated that adding BA in the culture medium increase plant height, number of panicles, panicle length and leaf chlorophyll content. Plantlets obtained from in vitro culturing shoot tip on 0.5 mg/L BA containing medium gave the highest results in average plant height at 189.50 cm, number of panicles at 34.00 panicles, panicle length at 32.50 cm and leaf chlorophyll content at 39.65 SPAD unit. The results from this present study indicated the production of new plant types or characteristics for Sang Yod Phatthalung rice for high yield in future. HIGHLIGHTS The effect of concentrations of PGRs, and culture conditions on agronomical and physiological characteristic were evaluated 5 mg/L BA-derived plants germinated in vitro gave higher results than ex vitro in agronomical and physiological characteristic Addition of 0.5 mg/L BA in the medium increases the plant height, number of panicles, panicle length and leaf chlorophyll content 5 mg/L BA-derived plants in vitro gave the highest plant height, number of panicles, panicle length, and leaf chlorophyll content at 189.50 cm, 34.00 panicles, 32.50 cm, and 39.65 SPAD units, respectively GRAPHICAL ABSTRACT

Efficacy of Seed-Biopriming with Trichoderma spp. and Foliar Spraying of ZnO-Nanoparticles Induce Cherry Tomato Growth and Resistance to Fusarium Wilt Disease.

Several microbes that cause plant diseases drastically lower the production of agriculture and jeopardize the safety of the world's food supply. As a result, sustainable agriculture requires disease management tactics based on modern, eco-friendly techniques as alternatives to various agrochemicals. The current study aimed to assess the antifungal activity of ZnO-nanoparticles against Fusarium solani in-vitro, and the ability of two antagonistic Trichoderma isolates, Trichoderma viride and Trichoderma harzianum, to produce antifungal secondary metabolites and identify them using gas chromatography-mass spectrometry, and to evaluate the combined effects of foliar spray of ZnO-nanoparticles and bioprimed seeds of cherry tomato (Solanum lycopersicum L.) with two antagonistic Trichoderma isolates against Fusarium wilt disease caused by Fusarium solani in greenhouse conditions. The results revealed that, in-vitro, the highest concentration of ZnO nanoparticles (3000 ppm) resulted in the greatest decrease in Fusarium solani mycelial growth (90.91% inhibition). The scanning electron microscopy demonstrated the evident distortion in Fusarium solani growing mycelia treated with ZnO-nanoparticles, which might be the source of growth suppression. Additionally, twenty-eight bioactive chemical compounds were isolated and identified from Trichoderma spp. ethyl acetate crude extracts using gas chromatography-mass spectrometry. In a greenhouse experiment, the combination of bioprimed cherry tomato plants with Trichoderma harzianum and foliar spraying of ZnO-nanoparticles at 3000 ppm was the most effective interaction treatment for reducing disease severity index (23.4%) and improving the vegetative growth parameters, micronutrient contents (Mn, Zn, and Fe in leaves), and chlorophyll content (SPAD unit), as well as stimulating phenylalanine ammonia-lyase activity of cherry tomato leaves at 75 days after sowing. In conclusion, the antifungal potential of seed-biopriming with antagonistic Trichoderma isolates and the foliar spraying of ZnO-nanoparticles can boost cherry tomato growth and confer resistance to Fusarium wilt caused by Fusarium solani.

An Analysis of the Growth and Photosynthetic Responses of Potted <italic>Veronica pusanensis</italic> Y.N.Lee according to the Shading Levels

Background and objective: Veronica pusanensis, an endemic species of South Korea belonging to the Plantaginaceae family, is found in Busan, South Korea. Due to its high ornamental value, it is expected to be utilized as a flower crop. However, currently it is an endangered species with its habitats being destroyed and reduced.Methods: Therefore, in this study, we analyzed the growth and photosynthetic responses of potted plants of V. pusanensis under different shading levels to enable mass production. Polyethylene (PE) shading films were selected as the shading material, and shading levels were designed at 0, 35, 45, 60, 75, and 99%, respectively.Results: Results showed that shoot height, shoot width, ground cover, leaf length, leaf width, shoot fresh and dry weight, chlorophyll content (SPAD units), and chlorophyll fluorescence parameters Fv/Fm and PIABS were highest under the 35% shading level. This indicates that it is relatively more desirable to grow V. pusanensis in shade culture compared to under direct sunlight. Meanwhile, root fresh weight and dry weight were highest under the 0% shading level.Conclusion: Therefore, it is recommended to grow V. pusanensis under direct sunlight to significantly increase root biomass when the purpose is to facilitate rootage when transplanting plants for habitat restoration. On the other hand, for the cultivation of V. pusanensis as an ornamental flower crop, it is recommended to grow the plants under the 35% shading level to significantly increase plant sizes and maintain ensure the proper functioning of photosynthetic responses in photosystem II (PSII).

Comparison of Growth and Leaf Color Quality of <italic>Mesembryanthemum cordifolium</italic> f. <italic>variegata</italic> as Affected by Shading Levels

Background and objective: Mesembryanthemum cordifolium is a plant belonging to the Aizoaceae family and is native to South Africa and Namibia. As a CAM plant, M. cordifolium exhibits strong resistance to drought stress and can be utilized for the removal of soil salinity and heavy metals. Furthermore, it is an important medicinal crop with anti-inflammatory and antidepressant effects. However, despite its potential benefits, research on the optimal growth environment for M. cordifolium remains scarce.Methods: Therefore, this study selected M. cordifolium f. variegata with high ornamental value as the experimental plant and compared the effects of different shading levels on the growth and leaf color quality of variegated baby sun rose (M. cordifolium f. variegata). Six shading levels (0, 35, 45, 60, 75, and 99%, respectively) were designed using polyethylene (PE) shading films.Results: The results showed that the shoot height, shoot width, dry weight, and chlorophyll content (SPAD units) were highest under the 60% shading level, while leaf length, leaf width, and fresh weight were highest under the 75% shading level. On the other hand, growth was relatively lower under the 0% shading level, which suggests that M. cordifolium f. variegata prefers shade over direct sunlight. On the contrary, M. cordifolium f. variegata showed growth even under the 99% shading level, proving to have strong shade tolerance, but the leaf color quality was lowerst.Conclusion: In conclusion, to significantly increase the size and biomass of plants and improve leaf color quality when cultivating M. cordifolium f. variegata under shading treatment, it is recommended to cultivate it under 60-75% shading levels.

Effects of Citric Acid and Humic-like Substances on Yield, Enzyme Activities, and Expression of Genes Involved in Iron Uptake in Tomato Plants

Iron (Fe) deficiency is a common abiotic stress on plants growing in calcareous soils where low organic matter content, high carbonate–bicarbonate concentration, and high pH precipitate Fe in unavailable forms. Enzymatic activity is a mechanism for plants to access soil nutrients; enzymes such as H+-ATPase, phosphoenolpyruvate carboxylase (PEPC), and the intracellular enzyme ferric reduction oxidase (FRO) are involved in Fe absorption. The effects of the application of citric acid (CA) and humic-like substances (HLS) on the yield, H+-ATPase, PEPC, and FRO enzyme activity, and expression of LeHA1, LePEPC1, and LeFRO1 genes in tomato plants grown under calcareous soil were studied. CA and HLS improved the SPAD units and increased the number of harvested fruits and yield per plant. Temporary alterations in enzyme activity, which reduced PEPC and FRO activity in roots, were documented. In leaf tissue, CA resulted in lower expression of LeHA1 and LePEPC1 and the induction of LeFRO1 expression, whereas HLS application resulted in higher expression of LePEPC1 and LeFRO1. In roots, LeHA1 expression increased with HLS, whereas LePEPC1 and LeFRO1 showed lower expression with CA and HLS, respectively. The application of CA and HLS through a nutrient solution in combination with Fe-chelate can improve Fe nutrition in tomato plants potted in calcareous soil by inducing temporal alterations in PEPC and FRO enzyme activity and LeFRO1 and LeHA1 gene expression.

Physiological and anatomical response of rice (Oryza sativa L.) ‘Hom Mali Daeng’ at different salinity stress levels

Abstract Soil salinity is a severe global stressor causing adverse impacts on irrigated land and drastically reducing crop yields, especially in rice, an important economic crop of Thailand. In this study, the impacts of salt stress on the anatomical and physiological features of 28-day-old rice (Oryza sativa L.) ‘Hom Mali Daeng’ were determined. Various NaCl concentrations (0, 50, 100, 150, and 200 mM) were applied every 2 days, with watering for 2 weeks. The results revealed that salinity stress inhibited the growth of rice. Leaf number, root size, fresh weight, and dry weight were significantly reduced. The electrolyte leakage percentage and malondialdehyde (MDA) content increased after treatment with high NaCl concentrations, while the SPAD unit and chlorophyll content were not significantly different between the control and NaCl treatments. Leaf anatomy changes were studied using freehand section and peeling techniques after salinity stress treatment. Lamina thickness in all treatments decreased, while cell wall and cuticle thickness increased. Stomatal density in all treatments significantly increased. Major vascular bundle, vessel, and phloem area of the 100 mM NaCl treatment were different when compared with the control and other treatments. The results provide information about the physiological and anatomical adaptation of ‘Hom Mali Daeng’ rice, which will be useful for further research in this and other rice cultivars.

In vitro and in vivo screening for the identification of salt-tolerant sugarcane (Saccharum officinarum L.) clones: molecular, biochemical, and physiological responses to salt stress

Sugarcane is a glycophyte whose growth and yield can be negatively affected by salt stress. As the arable lands with potential saline soils expand annually, the increase of salt-tolerance in sugarcane cultivars is highly desired. We, herein, employed in vitro and in vivo conditions in order to screen sugarcane plants for salt tolerance at the cellular and at the whole plant levels. Calli of sugarcane cv. Khon Kaen 3 (KK3) were selected after culturing in selective media containing various NaCl concentrations, and regenerated plants were then reselected after culturing in selective media containing higher NaCl concentrations. The surviving plants were finally selected after an exposure to 254 mM NaCl under greenhouse conditions. A total of 11 sugarcane plants survived the selection process. Four plants that exhibited tolerance to the four different salt concentrations applied during the aforementioned screening process were then selected for the undertaking of further molecular, biochemical, and physiological studies. The construction of a dendrogram has revealed that the most salt-tolerant plant was characterized by the lowest genetic similarity to the original cultivar. The relative expression levels of six genes (i.e., SoDREB, SoNHX1, SoSOS1, SoHKT, SoBADH, and SoMIPS) were found to be significantly higher in the salt-tolerance clones than those measured in the original plant. The measured proline levels, the glycine betaine content, the relative water content, the SPAD unit, the contents of chlorophyll a and b, as well as the K+/Na+ ratios of the salt-tolerant clones were also found to be significantly higher than those of the original plant.When the salt-tolerant clones were grown in a low saline soil, they exhibited a higher Brix percentage than that of the original cultivar.