Acute Toxicity of Commonly used Insecticides to Red Pumpkin Beetle, Aulacophora foveicollis

Acute toxicity of commonly used insecticides viz., fipronil, cyantraniliprole, fluxametamide, phenthoate and thiamethoxam were determined against Red pumpkin beetle, Aulacophora foveicollis collected from the unsprayed pumpkin fields in the orchard of Tamil Nadu Agricultural University, Coimbatore using filter paper disc bioassay method. Based on the LC50 values (ppm) of different insecticides, the order of toxicity was found to be fipronil (6.822) > fluxametamide (11.953) > phenthoate (14.732) > cyantraniliprole (14.793) > thiamethoxam (29.465) at 24 and 48 hours after treatment (HAT). The respective LC95 values were 65.396, 87.077, 42.090, 203.017 and 205.013 against A. foveicollis at 24 HAT and 46.585, 54.242, 37.445, 223.682 and 146.267 at 48 HAT for fipronil, cyantraniliprole, fluxametamide, phenthoate and thiamethoxam, respectively. The study results clearly indicated that the phenyl pyrazole insecticide, fipronil was highly effective against the pumpkin beetle, A. foveicollis.

Influence of Specific Gravity Grading Using Floatation Technique on seed and Seedling Quality Characteristics in Amaranthus CV. PLR 1

Study was undergone to evaluate the efficacy of floatation grading on the seeds of Amaranthus Cv. PLR 1 using organic solvents in Department of Seed Science and Technology, TNAU, Coimbatore during March 2023.The experiment was laid out in Completely Randomized Design with four replications in each five treatments. We considered four organic solvents viz., Acetone, Methanol, Dichloromethane and Petroleum Ether along with water and observed the seed recovery percentage, germination percentage, root length, shoot length and vigour index of all the treatments. The results showed that sinker fraction regardless of organic solvent and water performed better than floater fraction. The grading ability of Dichloromethane was greater among the assessed organic solvents. The sinkers seed recovery percent of dichloromethane (93%) was higher than sinkers recovered by water (63%). Also, the sinkers of dichloromethane recorded higher germination percent(77%) and vigour index(304) than the sinkers of water whose germination percent is 55% and vigour index is 272.This specific gravity grading using dichloromethane can be adopted to segregate well filled and ill filled seeds in a seed lot of Amaranthus. This method of floatation grading is a good substitute for sieve grading which requires skilled labour and availability of specific size sieve to properly segregate seeds. So, this can be used as an alternate method for grading Amaranthus seeds.

Potentials of Constructed Wetland for the Treatment of Wastewater from Cocopeat Production Industry

The cocopeat production industry generates a significant amount of wastewater containing high organic loads and chemical residues, posing environmental challenges and economic concerns. This study aims to assess the potential of constructed wetlands as an innovative and sustainable approach for managing coco peat production industry wastewater. An artificial wetland was created and filled with 30% soil, 40% sand, 10% bio and hydrochar, and 20% gravel along with Canna indica was used as the plant component. Three types of hydraulic loading rates were studied: 5 ml/min, 10 ml/min, and 15 ml/min, with a retention time of 7 days.The results showed that the wastewater contains significant levels of Electrical Conductivity (5.24 – 6.31 dS m-1), Total Dissolved Solids (4190 - 5150 mg/L), Biochemical Oxygen Demand (730 - 818 mg/L), and Chemical Oxygen Demand (1825 – 2045 mg/L). The utilization of artificial wetlands along with Canna indica decreased the pollution loads by 42% of Electrical Conductivity, 41% of Biochemical Oxygen Demand, and Chemical Oxygen Demand, 45% of Total Suspended Solids, and 55% of Total Dissolved Solids.Based on the above results, constructed wetlands are recognized as a reliable wastewater treatment technique and a good solution for the treatment of coirpith washwater, which is a step towards a greener and more sustainable future. By integrating these natural filtration systems into the wastewater treatment process, industries can foster a harmonious coexistence with the environment, ensuring a balance between economic growth and environmental well-being.