Test Of The Indian Tea Field Soil

The isolated selected bacteria were considered for response properties study against several manures, other than organic or biomanure or bacterial fertilizer used in tea field and some herbicide. Most of the tested bacterial isolate showed tolerance against urea, potassium chloride, and single super phosphate rendering their stress tolerance activity towards act as bioaccilerant. Most of the bacterial isolates showed positive cellulose utilization test. Indian soil is rich in cellulose, a polysaccharide. So cellulose digestion can also be considered a good attribute of biofertiliser. Since, glyphosate and 2,4-D has potent weedicide properties and frequently used in tea field , the bacterial isolate under study showing tolerance against these chemical more than the prescribed level, would be considered for good biofertiliser in a conventional garden.

Most of the bacterial isolate showed a positive response in the Indole acetic acid production. Zhan et al., 2016 observed that a tea specific isolates of Herbaspirillum (WT00C) induces the lateral root formation and enhance the tea cutting bud growth. Efficacy of six nonsymbiotic free living soil bacteria, namely DS-1-20 (Stenotrophomonas sp Accession No. KY636360), DS-2-10 (Herbaspirillum sp Accession No. KX587468), DJ-1-22 (Burkholderia sp Accession No. KY 859855), DJ-1-3 (Burkholderia sp Accession No. KY 636359), TS-3-15 (Stenotrophomonas sp Accession No. KY631488) and AS-1-4 (Stenotrophomonas sp Accession No. KY636361) has evaluated in tea fields of North Bengal Tea Gardens for subsequent two years. The remarkable increase in yield (green leave production) and plucking point comparable to the control is observed. Among the six isolates so far tested the DS-2-10 i.e. a bacterium of the genus Herbaspirillum sp have showed maximum response compared to the other five isolates in the context of green leaf production (145kg in first year and 150.87kg in second year) and plucking point (88.75 in first year and 91 in the second year) which are statistically significant (P<0.001). It is evident from the result that the highest enhancement of green leaf production in the first and second year with the use of biomanure in comparison to the control is 20.81%, and 25.40% respectively.

Tea production is rapidly increasing in India due to farmers are coming to scenario as small grower. The export of Tea remains stagnant due to deterioration of good quality tea as per the export standard. In this context betterment of quality is utmost important to need the growing demand of Indian tea in abroad. The use of biofertliser in the tea field makes good quality as well as quantity of exportable tea. ` It is well established that the use of biofertilizer in several crop fields increases both yield and quality (Sucey 2006). The most common plant growth promoting rhizobacteria in Tea belongs to the genus Bacillus and Pseudomonas mainly B. subtilis and P. corrugata has been reported. B. subtilis is well known PGPRs in Tea for their antagonistic activity and tolerance towards stress. P. corrugata was found to produce siderophores, an antimicrobial substance causing the inhibition of fungal growth, and having phosphate solubilising and Nase activity (Trivedi et al., 2008, Pandey et al., 2004, Kokalis-burelle et al., 2006).

The P. corrugate is considered to be pshycotroph and can grow between 4oC and 35oC. The antagonistic activity among the six isolated bacterial isolates, DS-1-20 exhibit highest (24.6 mm diameter inhibition zone) positive response against Alternaria alternata, TS-3-15 and DS-1-20 showed higher (15.4 mm diameter inhibition zone) positive response against forms lameness, DS-1-20 also showed positive response (15.5 mm diameter inhibition zone) against Phomopsis theicola . A large number of bacteria and fungi were isolated from the zone adjacent to the root of established tea bushes and were tested for their antifungal activity (Pandey et al., 1997). Ochrobactrum anthropi BMO-111 bacterial isolate has been reported to be acting as an antifungal agent against blister blight disease of Tea causing fungi Exobasidium vexans (Sowndhararajan et al., 2012).