Isolation of Drought-Tolerant Endophyte Bacteria From Local Tomato Plants.

Abstract

<b>Background and Objective:</b> Exploration of drought-tolerant endophytic bacteria is significant to identify bacteria that can provide plant resistance to drought stress. This study aims to obtain the potential of endophytic bacteria to promote plant growth from tomato plants in dry land. <b>Materials and Methods:</b> Exploration of endophytic bacteria from healthy tomato plants in a dry and rocky land, Muna Regency, Indonesia. Selection of drought-tolerant endophytic bacteria using polyethylene glycol 6000. Selected isolates were tested to increase the viability of tomato seeds using a Completely Randomized Design (CRD). <b>Results:</b> There were 123 isolates of endophytic bacteria isolated from the roots and stems of local tomato plants in a dry and rocky land, Muna Regency, Indonesia. There were 39 (31.70%) isolates sensitive to drought, 55 (44.71%) isolates very sensitive to drought, 8 (6.50%) isolates tolerant to drought and 21 (17.02%) isolates very tolerant to drought. Dryness for the maximum polyethylene glycol concentration at osmotic pressure of -2.00 MPa. Inoculation of endophytic bacteria in local tomato seeds increased the viability and vigour of local tomato seeds compared to the absence of endophytic bacteria. Of the 21 isolates of drought-tolerant endophytic bacteria, there were 12 potential isolates in increasing the viability of local tomato seeds belonging to the <i>Pseudomonas</i> sp. and <i>Bacillus</i> sp. bacterial groups. <b>Conclusion:</b> <i>Pseudomonas </i>sp. and Bacillus sp. isolates identified the endophytic bacteria, which can be drought-tolerant and increase tomato seeds' viability.