Promotion of Cotton Seedlings Growth Characteristics by Development and use of New Bioformulations

摘要

This study was carried out at the Department of Plant Pathology of the Iranian Research Institute of Plant Protection during the period from January 2009 to December 2009 to develop some new bioformulations and evaluate their efficacy in promoting cotton seedlings growth characteristics. The interest in the use of biological approaches to replace chemical agents in fertilizing soils or improve plant resistance against phytopathogens is at present in continuous growth. In this regard, the use of PlantGrowth Promoting Rhizobacteria (PGPR) has a potential role in developing sustainable systems for crop production. In search of efficient PGPR strains with multiple activities, we prepared eight bioformulations using two isolates of Pseudomonasfluorescens Q13 (BJ and CKK-3 (B2) which were isolated from rhizospheric soil and cotton roots in Varamiris cotton fields. Formulations included a talc-based powder and bentonite-based powder as inorganic carriers and peat and rice bran as organic carriers for increasing stability in interaction between associated PGPR and cotton plants. The results of a greenhouse experiment 60 days after sowing indicated that efficacy of BENT-Bi, TAL-B_1 and PT-B_1 treatments were 1.38,1.35 and 1.27 fold, BENT-B,, PT-B_1 and TAL-B_1 treatments were 1.42,1.41 and 1.28 fold, RB-B_2, TAL-Band RB-B_1 treatments were 3.44, 3.37 and 2.90 fold and TAL-Bj RB-B2 andRB-B_1 treatments were 2.60, 2.50 and 2.10, respectively on promoting seedling height, root length, seedling dry weight and root dry weight more effective than the control treatment.