Suitability of de-oiled cakes of Neem, Jatropha, Mahua and Karanja along with cereals and millets substrates for mass multiplication of Trichoderma harzianum.

Abstract

Mass multiplication and longer shelf life with higher population dynamics of biocontrol agents have been a challenge for plant pathologists. Several low cost substrates have been evaluated from time to time, but one or other associated demerits have interrupted the pace of success in this direction. Talc and millet’s grain based carrier have also been evaluated. During present investigation, de-oiled cakes of four tree Born Oilseed’s (TBOs) i.e. neem, jatropha, mahua and karanja, sorghum grain and wheat brawn were tested in different combination to select a best performing substrate for higher population dynamics with longer shelf life of T. harzianum . A substrate resulting from the mixture of all four cakes with sorghum grains and wheat bran was found to be the best for supporting a very high level of population dynamics and quite longer shelf life of T. harzianum i.e . for 150 days. This combination not only supported the highest population dynamics of T. harzianum (86.17×10 6 at 30 days period only) rather also supported longer shelf life i.e. 150 days in vitro . However Neem, Jatropha, Mahua and Karanja cakes alone could support the longevity of T. harzianum up to 105 days only with comparatively lower population dynamics than mentioned above. On the basis of these findings, de-oiled cakes of Neem, Jatropha, Mahua and Karanja with sorghum grains and wheat bran can be used for mass multiplication of T. harzianum and P. fluorescens and also for longer shelf life of around 150 days. Presence of de-oiled cakes of neem+sorgum grains and de-oiled cakes of jatropha + sorghum grains in any substrate/mixture ensured the viability of T. harzianum . Presence of these substances i.e.de-oiled cakes of neem, de-oiled cakes of jatrofa, and sorghum grains in any mixtures also ensured comparatively higher population dynamics than those where these substances were absent.