Evaluating the effect of supplementary lighting on the growth and physiological activity of roses during winter by plant-induced electrical signal

Limited light intensity and low temperature in winter lead to various challenges such as reduction in growth, yield and quality of cultivated roses, which can be complemented by artificial supplementary lights. This study aims to evaluate the effect of different supplementary lights, including metal-halide (MH), metal-halide+high-pressure sodium lamp (MH + HPS) and high-pressure sodium lamp (HPS) on the growth characteristics of cultivated roses in winter. Compared to individual light, the results demonstrated that combined supplementary lights (MH + HPS) increased stem diameter, number of leaves and flower diameter of cultivated roses. The height, leaf length, leaf width, number of petals, chlorophyll content and chlorophyll fluorescence (Fv/Fm) of roses grown in different supplementary lights were not significantly affected. In all the three treatment areas, photosynthetic photon flux density (PPFD) and temperature at night were higher in the MH + HPS area, followed by the HPS and MH areas. The plant-induced electrical signal (PIES) of roses cultivated under MH + HPS light indicated higher water and nutrient uptake than other treatments, which was positively associated with rose growth, but the difference was insignificant. Principal component analysis (PCA) revealed that the growth parameters of roses were mainly associated with MH + HPS supplementary light. Therefore, combined supplementary light was beneficial to improve the growth and quality of cultivated roses

Composting textile sludge using PGPRs grown sugarcane bagasse in a solid state bioreactor- a next step towards zero discharge of waste from textile industry

Abstract Generation of solid dye waste during wastewater purification especially in coagulation/precipitation steps and its detoxification is a major issue since it again leachate in the ground water from the landfills because of rains. The semisolid textile waste (sludge) showed 99 and 97% decolourization at flask and reactor scale within 72 h, respectively when treated with consortium ARBR (Azotobacter vinelandii MTCC 1241, Rhodobacter erythropholis MTCC 4688, B. megaterium NCIM 2054 and Rhizobium meliloti NCIM 2757). The decolourization rate of textile sludge majorly affects by the pH, temperature and moisture content of the sludge. At the optimum conditions of pH (6), temperature (30 oC) and moisture content (90%) the consortium showed maximum decolourization of 81, 84 and 97, respectively. A significant increase in the activities of oxidoreductase enzymes such as lignin peroxidase (5 fold), laccase (2.6 fold), veratryl alcohol oxidase (4.7 fold) and tyrosinase (2.9 fold) was observed; while azo reductase (-1.3 fold) showed a decrease in the activity during sludge treatment. In addition, a noteworthy reduction in the concentration of macromolecules N (45%), P (70%), K (50%) and C (63%), and microelements B (59%), Cu (50%), Fe (59%) and Mn (75%) were also observed after treatment with sludge bed reactor. Bio-transformed sludge showed less toxic effects on plants. The outcome from the sludge bed bioreactor (solid state bioreactor) was found to be more effective and can be used using sugar industry waste like sugarcane bagasse (SCB) for composting.</jats:p