effect of biopriming with bioagents on physiological and biochemical mechanism of seedling establishment and seed health of tomato and chilli

Abstract

ABSTRACT newlineEFFECT OF BIOPRIMING WITH BIOAGENTS ON PHYSIOLOGICAL newlineAND BIOCHEMICAL MECHANISM OF SEEDLING ESTABLISHMENT newlineAND SEED HEALTH OF TOMATO AND CHILLI newlineBy newlineC. Mohan Raj newlineDegree : Doctor of Philosophy (Agriculture) in Seed Science and Technology newlineChairman : Dr. S. SUNDARESWARAN, Ph.D., newlineProfessor (SST) newlineO/o. The Dean (Agri.) newlineTamil Nadu Agricultural University newlineCoimbatore - 641 003 newline2019 newlineStudies were undertaken at the Department of Seed Science and Technology, newlineTamil Nadu Agricultural University, Coimbatore to standardize optimum concentration of newlinebioagents for seed priming; to evaluate the effect of biopriming on physiological, biochemical newlineand anatomical changes during seed germination and seedling establishment; to study the newlineperformance of bioprimed seeds under stress conditions; to study the effect of biopriming on newlineassociation of seedborne pathogens and population dynamics of bioagents; and to newlinecharacterise the antimicrobial peptides / proteins associated with bioprimed seeds of newlinetomato cv. PKM 1 and chilli cv. K 2. newlineExperiments conducted to standardise the optimum concentration of bioagents for newlinebiopriming of tomato and chilli seeds revealed that seeds primed with 6% Bacillus subtilis 1 newlinefor 9 hours for both tomato and chilli, 4% Methylobacterium extorquens AM 1 for 9 hours newlinefor tomato, 6% Methylobacterium extorquens AM 1 for 9 hours for chilli and 8% newlinePseudomonas fluorescens Pf 1 for 9 hours for both tomato and chilli recorded significantly newlinehigher speed of germination, germination percentage, seedling growth and vigour index newlinewhen compared to other concentrations of respective bioagents. newlineThe studies conducted to know the effect of best performing concentration of newlineeach bioagents on physiological, biochemical and anatomical changes during seed newlinegermination and seedling establishment indicated that the tomato seeds bioprimed newlinewith 8% Pseudomonas fluorescens Pf 1 for 9 hours showed its superiority than the other newlinetreatments by recorded higher rate of imbibition (25.4%), radicle emergence (25.8%), radicle newlinelength (1.3