Greenhouse Plant Production Journal

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 The aim of this study was to explore how various spectra of complementary light impact the growth and development of strawberry plants under stress conditions caused by salinity and alkalinity. The experiment involved cultivating plants in a greenhouse with ambient light, subjecting them to blue (460 nm), red (660 nm), blue/red (1:3), and white/yellow (400-700 nm) light at different developmental stages. Stress treatments included control (without stress), alkalinity (40 mM NaHCO3), and salinity (80 mM NaCl). Results indicated a decrease in dry weights under salinity and alkalinity stress. The blue and red spectra were more effective in mitigating stress effects compared to other spectra. While stress conditions led to a reduction in SPAD, blue light increased SPAD under stress. Stress conditions decreased RWC, and blue/red light increased RWC under stress conditions. Blue/red and white/yellow light had the most significant impact on reproductive traits. Salinity and alkalinity stress reduced OJIP curves compared to the control, but the blue and red spectra increased OJIP curves under their respective stress conditions. In conclusion, manipulating the supplemental light spectrum can alleviate the effects of salinity and alkalinity stresses, suggesting the potential extension of artificial light use in stress conditions.

Abstract In order to assess the impact of various nutrient solutions on the nutrient content of cucumber plants, a factorial experiment was conducted with two factors: cultivation system (soil cultivation and soilless cultivation) and nutrient solution (Hoagland, Papadopoulos, and Commercial). The experiment was carried out in a completely randomized design with three replications in a greenhouse setting. The results showed that the highest concentrations of N, K, Ca, Mg, and Fe in the leaves were obtained from plants grown in a hydroponic system and fertigated with the Hoagland nutrient solution. Additionally, plants grown in the hydroponic system had the highest P content, while those grown in soil-based cultivation had the lowest phosphorus levels. Moreover, plants grown in a hydroponic system with a combination of Hoagland and commercial nutrient solutions exhibited the highest levels of Zn and Cu. The highest manganese content was observed in plants grown in the hydroponic system with the Hoagland and commercial nutrient solutions. Overall, the results suggest that soilless cultivation with the Hoagland nutrient solution had a significantly positive impact on the nutrient content of cucumber plants compared to the other treatments.

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 Yield and plant growth are affected by fertilization and irrigation. Therefore, effective fertilization methods and optimum use of fertilizers play a major role in improving fertilizer use efficiency and plant yield. This experiment was conducted to investigate the effects of nitrogen, potassium, and iron fertilizers on growth indices, photosynthetic pigments, mineral element concentrations, and yield indices of melon plants grown under field conditions. The fertilizer treatments were applied via fertigation and consisted of a control, as well as treatments with urea, potassium sulfate, Fe-EDDHA, urea + potassium sulfate, urea + Fe-EDDHA, and urea + potassium sulfate + Fe-EDDHA. The experiment was laid out in a randomized complete block design with three replications. The results showed that the application of urea, potassium sulfate, and the combined application of these fertilizers increased the fresh and dry weight as well as the shoot length of the melon plants. However, the application of Fe-EDDHA alone had no significant effect on the growth indices. Regarding fruit yield indices, the number, length, diameter, and total yield of the fruits increased under the urea, potassium sulfate, urea + potassium sulfate, and urea + potassium sulfate + Fe-EDDHA treatments compared with the control. The application of urea and potassium sulfate as fertigation can be considered an effective management strategy to enhance the growth and yield parameters of melon plants.

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.