Greenhouse Plant Production Journal

Abstract Salicylic acid (SA) is a key signaling molecule that regulates plant growth, flowering, and responses to abiotic and biotic stresses. This study evaluated the effects of different SA concentrations (0, 0.5, and 1.0 mM) and application frequencies (once and twice) on the growth, pigment composition, and yield of eggplant (Solanum melongena L.) under field conditions during the 2023–2024 growing season. Eggplant seeds were sown in a cocopeat and perlite growing medium at a ratio of 3:1 and the seedlings were watered daily in greenhouse. Foliar spraying was done in two stages before transplanting (four-leaf stage) in greenhouse and before flowering in farm. After the first foliar spray, the eggplant seeds were transferred to the field and the plants were irrigated every three days throughout the growth period. A factorial experiment arranged in a completely randomized design revealed significant SA effects on most measured traits, with 0.5 mM producing the most favorable outcomes. Compared with the control, this treatment increased relative water content by 11%, reduced electrolyte leakage by 30–35%, and enhanced SPAD values, total chlorophyll, and carotenoid contents by up to 120%. Plant height, fruit number, and total yield rose by 38.1%, 85.7%, and 88.6%, respectively. Two applications further improved growth and yield compared to a single spray, indicating that repeated applications amplify the physiological benefits of SA. In contrast, 1.0 mM SA provided no additional improvement, suggesting a threshold beyond which inhibitory effects are not observed. The observed enhancements were associated with improved water balance, enhanced photosynthetic efficiency, and increased membrane integrity. Overall, applying 0.5 mM SA twice during both the vegetative and reproductive stages proved to be an optimal, low-cost, and environmentally safe strategy for enhancing eggplant growth and productivity. Future studies should elucidate SA’s molecular mechanisms and interactions with other biostimulants and stresses to optimize its use across crops and production systems.

Abstract In vitro cultures provide a promising tool for large-scale multiplication of valuable plant species with an important role in the global ornamentals industry. In the current investigation, a rapid and efficient protocol was described for in vitro mass propagation of attractive ornamental plant Philodendron cv. Birkin through shoot tip culture. In shoot proliferation stage, 11 treatments of plant growth regulators were evaluated. The highest shoot multiplication was achieved by culturing explants in MS medium containing 3 mg/l benzyladenine (BA) and 0.5 mg/lit indole-3-butyric acid (IBA), resulting in average of 16.65 shoots per explant over a four weeks period. To induce adventitious root formation, the regenerated shoots were subsequently transferred to MS media supplemented with various concentrations of IBA and naphthalene acetic acid (NAA) (0.5-2 mg/l). In this regard, the superior performance of IBA compared with NAA was observed with the best response achieved using 1 mg/l IBA (resulting in a 95% rooting rate) with an average of 6.13 roots per shoot and the root length of 2.59 cm. Finally, the obtained plantlets were successfully acclimatized in a greenhouse, with 100% ex vitro survival rate. This established protocol can serve as an effective alternative to classical propagation methods for mass multiplication of this valuable decorative plant.

Abstract Artificial light source is one of the most important factors for high quality and quantity vegetable production in a plant factory. Aiming to investigate the role of light spectra on growth, chlorophyll fluorescence, photosynthesis and stomata parameters in lettuce plants grown in a plant factory, a factorial experiment was conducted based on a completely randomized design with two lettuce cultivars (Lollo Rossa and Lollo Bionda) and four spectra LED illumination red (656 nm), red/blue (3:1) (656 nm), blue (450 nm) and white (449 nm). The results showed that the combination of red and blue LED light had the greatest effect on stomatal conductance (gs), number of stomata, length and width of stomata in both lettuce cultivars. Also the maximum substomatal CO2 concentration (Ci) was observed in both lettuce cultivars when they were treated with red LED light. The results also showed that the maximum CO2 assimilation rate (PN) was observed in Rossa variety under white LED and in Bionda cultivar under blue LED light. Contrary to the results related to some of photosynthetic parameters, the highest values of vegetative traits (plant height, dry and fresh mass of shoots and roots, leaf number and leaf area) of plants were observed in the treatment of red and blue light combination. It is concluded that plant growth, chlorophyll fluorescence characteristics, photosynthetic and stomatal properties can be affected by different spectra and cultivars of lettuce, so that the choice of proper lighting is a fundamental requirement for the cultivation of this plant

Abstract Light plays a crucial role in plant growth and development, serving as both the main energy source for photosynthesis and an external signal. The use of artificial light (AL) for production of ornamental plants is growing nowadays. It is employed to enhance yield, prolonging the production season, improving product quality, and serve as photoperiodic light for regulating flowering in day length-sensitive species. Achieving successful plant growth with artificial lighting requires a careful balance of quality, intensity, and photoperiod. The numerous benefits of Light-emitting diodes (LED) technology make it an ideal choice for the ornamental industry, offering unparalleled energy efficiency, durability, compact size, long-lasting lifespan, and minimal heat emission. With the ability to carefully manipulate light quality to impact specific characteristics of plants such as architecture, pigmentation, and flowering, it is no wonder the industry is paying close attention to the potential of controlling the growing environment. By utilizing lighting technology, growers can gain various positive outcomes, such as strategic production (with options for early flowering, continuous production, and consistent yields), enhanced plant structure (improved root growth and size, stem elongation, etc), determination of leaf and flower color, and elevated product quality. When it comes to lowering energy and chemical usage (specifically pesticides and plant growth regulators), LED technology provides the floriculture industry with a solid and eco-friendly alternative. In this review paper the significance of ornamental flower production in controlled environment agriculture (CEA), together with the proper lighting strategies for production of ornamental plants are discussed.

Abstract To evaluate the effect of different nutrient solutions on growth and yield characteristics of tomato plants, as well as to evaluate the quantitative and qualitative characteristics of fruit in soil- and soilless-cultivation, factorial experiment was carried out with two factors of cultivation system at two levels (soil cultivation and soilless cultivation) and three levels of nutrient solution (Hoagland, Hochmat and Shan) in a completely randomized design with three replications in greenhouse conditions. The results showed that soilless culture medium (cocopeat-perlite) increased vegetative and reproductive characteristics, such as plant height, number of nodes, flowers and fruits, internode distance, number of leaves, leaf area, fresh and dry weight of shoots, fresh and dry weight of roots, stem diameter, and fruit diameter in tomato plants. Many growth and morphological traits, such as leaf area, stem length, stem fresh weight, root dry weight, fruit diameter, leaf number, fruit number and yield were influenced by the interaction effect of nutrient solution and cultivation system. The photosynthetic pigments, and fruit quality traits including fruit appearance color (three components a*, b* and L*), Hue angle, chroma, total soluble solids (TSS), and vitamin C increased in soilless system compared with soil-based system. Hoagland nutrient solution had higher significant effect on increasing quantitative and qualitative traits than other nutrient solutions. In general, soilless cultivation with Hoagland nutrient solution had a significant positive effect on growth and yield characteristics, as well as the quantitative and qualitative characteristics of fruit compared with the other treatments.

Abstract Parsley possesses a high nutritional content, which includes vitamins A, B, and C, as well as essential mineral nutrients. The purity and chemical composition of fertilizers containing the same element can vary significantly. This difference has an important effect related to the method of usage, time of application, and the effectivity of fertilizers. Nitrate, ammonium, and urea are the primary sources of mineral nitrogen for higher plants, each with distinct chemical properties and varying impacts on plant growth. Hence, to examine the impact of various nitrogen sources on parsley, a study was carried out using a factorial combination of three nitrogen forms (calcium nitrate, ammonium sulfate, and urea) and four nitrogen levels (0, 100, 125, and 150 kilograms per hectare). The study employed a completely randomized basic design with three replications. The findings indicated that all measured parameters were significantly influenced by the nitrogen (N) sources. The greatest fresh weight of shoots, fresh weight of roots, vitamin C concentration in the leaves, and concentration of calcium (Ca) in the leaves were achieved with an application of 150 kg/ha of calcium nitrate. The highest dry weight of shoots, plant height, length of leaves, and iron (Fe) concentration in the leaves were observed with an application of 150 kg/ha of ammonium sulfate. The highest levels of total chlorophyll (a+b) were recorded with an application of 150 kg/ha of urea.

Abstract This experiment aims to compare the effect of deficiency of macro and micro nutrients and perlite particles size on radish, in the factorial experiment was conducted in a completely randomized design with three replications. Factors include deficiency of nutrient elements (control, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, boron, and zinc) and growing media tested were small, medium and large perlite particles size. The results indicated that dry and fresh weight of the taproot, dry and fresh weight of the root, dry and fresh weight of shoot, leaf area, numbers of leaves decreased under nutritional deficiencies as among the high consumption nutrients, the nitrogen deficiency had the greatest effect on reducing vegetative traits. The results also showed that the amount of total soluble sugars of leaves in nitrogen and boron deficiency respectively had the highest and lowest increase. Chlorophyll content and chlorophyll fluorescence indices also had the highest and lowest decrease under nitrogen and boron deficiency conditions respectively. The amount of vitamin C in the taproot also decreased under conditions of nitrogen, potassium, phosphorus, magnesium, calcium and iron deficiency. The results also showed that perlite particles size had a significant effect on the value of these indices and the big size of perlite particles caused a significant decrease in growth indices, mineral elements concentration and photosynthetic pigments. According to the results of this study, it seems that the small size of perlite in substrate was better to absorb the nutrients and therefore suitable for proper growth of radish.

Abstract Green fodder plants serve as a vital source of nutrition for livestock. However, ensuring an adequate supply of these plants for livestock faces with challenges such as limited agricultural areas, water scarcity, and negative impacts from environmental and climatic factors. To address these challenges, various strategies can be employed. Hydroponic fodder production system is new technology that can be used to produce fodder for livestock feed without using land and soil. Hydroponic fodder production has gained significant attention and is a prominent area of research in the field of agriculture. Many countries are actively working towards developing and implementing this technology to enhance livestock feed production. The purpose of this study is to focuses on the chemical composition and nutritional value of hydroponic fodder in livestock production. Also, the effect of feeding hydroponic fodder on livestock production and productivity has been reviewed. This review helps determine the potential benefits and practical implications of incorporating hydroponic fodder into livestock feeding programs.