IN VITRO MANAGEMENT OF PURPLE BLOTCH OF ONION(ALTERNERIA PORRI) BY NEW FUNGICIDES AND BIOAGENTSP.P. KHANDAGALE, K.T. SURYAWANSHI, D.B. PATIL AND B.S. AROTEAbstract The oniontheâ Queen of Kitchen âis one of the most important and oldest vegetables, and culinarycommodities are grown in the world. They can be eaten raw, cooked, fried, dried or roasted. No Indian food iscomplete without onion. Purple blotch is one of the major foliar diseases having more than 90 % loss inyield. Ten different fungicides were tested in vitro at different concentration against the pathogen which wasisolated from diseased onion leaf. Out of which, kavach (Chlolorothionil) at 0.5% concentration with 67.70%inhibition, Dithan M 45 @0.25% con. shows 77.35% inhibition of pathogen, biltox (Copper Oxy Chloride) at0.1% concentration showing inhibition of pathogen as 86.47%. Recommended that Kavach and Dithan M-45 was use at higher concentration to manage the pathogen. In contrast to that the systemic fungicides likeScore maximum inhibition were found @ 0.1% concentration as 91.52%. Nativo@0.1% concentration havinginhibition as 98.52%.In Signet at 0.1% concentration as 99.11%. In opera at 0.1% concentration as 99.11%inhibition. Amister top at 0.1% concentration as 97.35% inhibition of pathogen. Tilt(Propiconazole 25Ec)fungicides, Where maximum inhibition were found at 0.1% concentration as 98.52%. In vitro study the useof bio agent shows that T. harzaniumcaused significantly maximum inhibition, 90.58 % against A. porrifollowed by T.viride (85.58%). The inhibitory effect of these bio agents was probably due to competition and/or antibiosis. While the bacterial bio agents like Bacillus subtillus (71.77%) and Pseudomonas flurosence(56.00%) found less effective against the pathogen. |