Chawla, NeenaShakya, Sandeep2023-12-122023-12-122022Shakya, Sandeep (2022). Exploring Garlic Biochemical Markers Against Root Knot Nematodes (Unpublished M.Sc. thesis). Punjab Agricultural University, Ludhiana, Punjab, India.https://krishikosh.egranth.ac.in/handle/1/5810202698The aim of the present study was to explore garlic biochemical markers and to evaluate garlic extract against root knot nematode of selected genotypes. The study included dry matter, total sugars, reducing sugars, starch, pyruvic acid, allicin and crude fibre in garlic of thirty genotypes. On the basis of allicin per cent, PG-114, PG-119 and PG-128 were selected as the best genotypes for evaluation of nematicidal properties of garlic extract keeping allicin as the main phytochemical. The garlic extract was made from three selected genotypes using different solvents (methanol and distilled water) of different concentrations (S1, S2, S3, S4 and S5). Out of these, PG-119 garlic extract prepared in methanol showed the best results in maximum egg hatching inhibition per cent over untreated control (84.01%, 83.63% and 82.57%) and juvenile mortality per cent (92.35%, 94.47% and 95.67%) after 24h, 48h and 96h respectively at S5 concentration (5.11 ug/ml) as compared to other concentrations applied for in-vitro observations. On the basis of the best performance of PG-119 under an in-vitro trial, it was selected for an in-vivo trial in which a single dose, as well as a double dose of S4 concentration (17.74 ug/ml), showed maximum reduction in root gall index (3.124 and 2.111), final soil population (381.791 and 284.323) and a number of egg mass of root-knot nematode (21.333 and 11.000) as compared to the untreated control. Also, maximum enhancement in plant growth such as plant height and plant weight were observed with the same concentration. Overall, the nematicidal properties of the garlic extract exhibited concentration and time-dependent behaviour.EnglishThesis