Optimization of Plant Growth Promoting Rhizobacteria (PGPR) Concentration for Enhanced Growth and Biomass of Pakcoy Brassica rapa L.) in Wick System Hydroponic Cultivation

Effect of Plant Growth-Promoting Rhizobacteria in the Hydroponic Cultivation of Red Amaranthus (Amaranthus Tricolor L.)

Growth and Yield Response of Tomato Plants (Solanum lycopersicum L.) to the Application of Liquid Organic Fertilizer and Plant Growth Promoting Rhizobacteria

Tomatoes (Solanum lycopersicum L.) are horticultural plants from the Solanaceae family that contain protein, carbohydrates, calcium, phosphate, iron, fat, and vitamins. Tomato production in Indonesia has declined due to the lack of nutrients absorbed by tomato plants. Efforts that can be made include the application of Liquid Organic Fertilizer (LOF) and Plant Growth Promoting Rhizobacteria (PGPR). This study was conducted to examine the interaction between LOF and PGPR and to determine the appropriate concentrations of LOF and PGPR for tomato plant growth and yield. The research was conducted from February to June 2025 in Ampeldento Village, Karangploso District, Malang Regency. The design used was a Factorial Randomized Group Design (FRGD) consisting of two treatment factors, namely LOF and PGPR. The LOF factor consisted of 4 treatment levels and the PGPR consisted of 3 treatment levels. Each treatment was repeated 3 times, resulting in 36 experimental units. If there was a significant effect, it was followed by a Honest Significant Difference (HSD) at the 5% level. The results showed that there was an interaction between the application of LOF concentration and PGPR concentration on the growth and yield parameters of tomato plants. The combination of 30 ml L-1 LOF and 40 ml L-1 PGPR produced higher average plant height, number of leaves, leaf area,fresh weight, dry weight, crop growth rate, total number of fruits per plant, fruit weight per plant, and fruit weight per hectare, so that combination is the appropriate treatment to support tomato plant growth and yield.

Influence of different Growing Media and Plant Growth Regulators on Seedling Growth in Papaya (Carica papaya L.)

The study was conducted in the Horticulture Experiment Field, Department of Horticulture, School of Advanced Agricultural Sciences and Technology, Chhatrapati Shahu Ji Maharaj University, Kanpur, during the year 2026. The primary objective was to evaluate the influence of diverse growing media and plant growth regulators (PGRs), particularly Gibberellic Acid (GA₃) and Naphthalene Acetic Acid (NAA), on the germination behaviour and seedling development of papaya under nursery conditions. The experiment included nine treatments with different combinations of PGRs and media: soil alone (control), soil mixed with vermicompost, Perlite and cocopeat in various proportions, and treated with GA₃ or NAA at 50 ppm. The treatments were assessed for their impact on seed germination, imbibition period, speed of emergence, seedling vigour, survival percentage, and morphological growth attributes such as seedling height, number of leaves, leaf area, root number and length, stem girth, fresh biomass and shoot-to-root ratio. Several germination parameters were recorded, including imbibition period, speed of emergence, germination percentage, seedling vigour index, and survival percentage. Seedling growth parameters such as seedling height, number of leaves, leaf area, stem girth, number and length of roots, fresh weight of shoot and root, and shoot-to-root ratio were evaluated at 30 and 45 days after sowing (DAS). The results revealed significant differences among the treatments. Treatment T4 (NAA @ 50 ppm with soil + vermicompost + Perlite in equal proportions) exhibited the shortest imbibition period (9.00 days), the highest speed of emergence (92.63), and the highest germination percentage (73.33%). It also produced the most vigorous seedlings with a seedling vigour index of 795.67 and the highest survival percentage of 95.83%. NAA treatments, particularly T4, consistently outperformed other treatments in terms of early emergence and uniform germination, due to enhanced enzymatic activity and rapid mobilization of seed reserves. On the other hand, Treatment T8 (GA3 @ 50 ppm with the same media composition of soil, vermicompost and Perlite) was particularly effective in promoting vegetative growth and root development. It recorded the maximum seedling height (15.01 cm), number of leaves (9.40), leaf area (34.37 cm²), root length (12.50 cm), number of roots (21.87), fresh shoot weight (4.20 g), fresh root weight (0.92 g), and shoot:root ratio (4.55). This indicates that GA₃ plays a key role in cell division and elongation, particularly enhancing root biomass and overall seedling establishment. The control treatment (T9), which involved only soil and no growth regulator, consistently showed the lowest performance across all parameters, including germination percentage (51.67%), seedling vigour (331.55), and survival percentage (77.58%), confirming the inadequacy of unamended soil and absence of growth-promoting substances for nursery-level papaya production. In conclusion, the study demonstrates that the integrated use of PGRs and a balanced growing medium significantly enhances papaya seed germination and seedling quality. For nursery managers and papaya growers, the combination of NAA @ 50 ppm with the soil + vermicompost + Perlite media mix (T4) is recommended for achieving superior germination and uniformity, while GA3 @ 50 ppm with the same media (T8) is ideal for enhancing root development and seedling vigour. These findings can serve as a practical guideline for improving the efficiency and success rate of papaya seedling production under nursery conditions.

Response of Planting Spatial and PGPR (Plant Growth Promoting Rhizobacteria) Concentration of Bamboo Roots on The Growth and Yield of Sweet Corn

The productivity of sweet corn must be continuously improved to meet increasing market demand. Inorganic fertilizers may reduce soil fertility. The application of (PGPR) derived from bamboo roots, which function as biofertilizers and biostimulants by enhancing nutrient availability and stimulating plant growth. Appropriate plant spacing is also an important agronomic practice for optimizing the use of light, water, nutrients, and growing space. This study aimed to evaluate the interaction between plant spacing and bamboo root PGPR concentration on the growth and yield of sweet corn. The experiment was conducted in Potroyudan Village, Jepara from December 2024 to March 2025 using a two-factor Randomized Complete Block Design (RCBD). The first factor consisted of three plant spacings (75 × 40 cm, 75 × 30 cm, and 75 × 20 cm), while the second factor included three PGPR concentrations (0, 25, and 50 ml L⁻¹). Data were analyzed using analysis of variance (ANOVA) followed by Duncan's Multiple Range Test (DMRT) at the 5% significance level. The interaction between plant spacing and PGPR concentration significantly affected plant height only at 6 weeks after planting. Plant spacing significantly influenced stem diameter, cob weight with husk, and cob length without husk. The 75 × 40 cm spacing produced the highest cob weight (276.48 g) and longest cob length (19.44 cm). PGPR concentration showed no significant effect, although 25 ml L⁻¹ tended to produce better growth and yield. Overall, plant spacing contributed more to sweet corn productivity than bamboo root PGPR under the conditions of this study.

Biochemical and microbial interactions of Sargassum wightii extract and plant growth-promoting rhizobacteria consortia enhance growth and yield of tomato (Solanum lycopersicum L.)

The results demonstrate that the combined application of S. wightii extract and PGPR can effectively enhance tomato productivity while reducing fertiliser usage by 25 %, and offers a sustainable approach to improving crop performance and reducing chemical fertiliser dependence.

Effect of plant growth promoting rhizobacteria on the growth promotion of Mustard CS61 (Brassica juncea)

Plant growth-promoting rhizobacteria consortia are used in the growth and augmentation of Mustard CS61 (Brassica juncea) under saline conditions to discover novel genes associated with stress tolerance and plant growth–promoting traits.