Effect of Vermicompost in Media on Growth,Yield and Fruit Quality of Cherry Tomato (Lycopersicon esculentun Mill.) Under Net House Conditions

Effects of VC application on tomato production and media properties can last for the third successive season, which was verified in this study to evaluate effects of VC application on growth, productivity and fruit quality of cherry tomato for the third season. Six treatments were designed similarly in the first and second seasons (unchanged design compared to the previous season), including: VC with rice husk ash (RHS) and coconut fiber (CF) 0% VC+ 50% RHS +50% CF (T1- control), respectively. 20%VC + 40% RHS + 40% CF(T2), 40% VC+ 30% RHS + 30% CF(T3), 60% VC + 20% RHS + 20% CF(T4), 80% VC + 10% RHS + 10% CF(T5), and 100% VC(T6). The results showed that the pH, EC, N, P, K, Ca, and Mg available in media were increased with the addition of VC. This finding revealed that the addition of VC significantly improved the physic-chemical media properties, increasing the EC and also increasing the macronutrients in the media resulting in substantial increased the yield and quality of tomato fruits. It is concluded that EC of VC was the key factor for the positive increase of the productivity and quality of tomato and the salinity (EC at 3.52 dS/m) causing restriction of water to fruits that resulted in the increase of the total soluble solids in tomato fruit and without affecting yield reduction.     

Effects of Continuously Applied Vermicompost on Media Properties,Growth, Yield,and Fruit Quality of Two Tomato Varieties

In the first and second seasons, growth and yield of tomato were also influenced by different vermicompost (VC) rates and reused VC. Obviously, increasing VC proportion led to the augmentation of electrical conductivity (EC), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) in planting media in both seasons. However, in the first season, the nutrient absorbent ability of tomato was remarkably higher compared to those in the second season due to higher available nutrient in the media of the first season. This may influence the shoot dry weight as well as the yield of tomato in both seasons. In T4 treatment, the yield attained the highest value in the first season for both varieties with the values of 562.3 and 812.4 g/plant for small honey (V1) and graces (V2), respectively. In the second season, the N, P, K, Ca, and Mg in media significantly decreased compared to those in the first season (496.4 g/plant-V1 and 508.3 g/plant-V2). In comparison, the yields in the first season were higher those in second season by 13.2% and 59.8% for V1 and V2, respectively. However, in the second season, the maximum yield found in T5 (508.3 g/plant-V1 and 682.2 g/plant-V2) and declining by 10.6 and 19.1% compared to those in the first season for V1 and V2, respectively. This can be explained that amounts of nutrients from the media in the first season had supported the growth and development of tomato, resulting deficiency of nutrients in the media for the second season.     

Enhancing growth,yield, biochemical,and hormonal contents of snap bean (Phaseolus vulgaris L.) sprayed with moringa leaf extract

Increasing growth and productivity of food crops via safe biostimulants is a very important issue in the current years. This study aimed to investigate the potential of moringa leaf extract (MLE) in improving the performance of snap bean (Phaseolus vulgaris L.) cv. ‘Paulista’ under field conditions. Hormonal analysis of MLE revealed its richness of various classes of phytohormones particularly salicylates. The results revealed that all MLE concentrations had a positive effect on growth, biochemical, yield, and yield related traits as well as yield quality of snap bean compared to control, and the effect was dose-dependent. Moreover, increasing pods yield of snap bean may be related to gibberellins (GA₇) content than other plant hormones. In conclusion, the leaf extract of moringa provides a good source of phytohormones that have a positive role to stimulate growth and productivity of snap bean plants.     

Novel α-Amylase Inhibitor Hemi-Pyocyanin Produced by Microbial Conversion of Chitinous Discards

α-Amylase inhibitors (aAIs) have been applied for the efficient management of type 2 diabetes. The aim of this study was to search for potential aAIs produced by microbial fermentation. Among various bacterial strains, Pseudomonas aeruginosa TUN03 was found to be a potential aAI-producing strain, and shrimp heads powder (SHP) was screened as the most suitable C/N source for fermentation. P. aeruginosa TUN03 exhibited the highest aAIs productivity (3100 U/mL) in the medium containing 1.5% SHP with an initial pH of 7–7.5, and fermentation was performed at 27.5 °C for two days. Further, aAI compounds were investigated for scaled-up production in a 14 L-bioreactor system. The results revealed a high yield (4200 U/mL) in a much shorter fermentation time (12 h) compared to fermentation in flasks. Bioactivity-guided purification resulted in the isolation of one major target compound, identified as hemi-pyocyanin (HPC) via gas chromatography-mass spectrometry and nuclear magnetic resonance. Its purity was analyzed by high-performance liquid chromatography. HPC demonstrated potent α-amylase inhibitory activity comparable to that of acarbose, a commercial antidiabetic drug. Notably, HPC was determined as a new aAI. The docking study indicated that HPC inhibits α-amylase by binding to amino acid Arg421 at the biding site on enzyme α-amylase with good binding energy (−9.3 kcal/mol) and creating two linkages of H-acceptors.