Application of plant growth promoting microorganisms to combat oak decline

The oak decline is a world and progressive phenomenon causing death and decrease of oak forest area whole world. This phenomenon is also spreading rapidly in Iran and it is necessary to replace dead trees and reclamation of affected habitats. It has been proved that plant growth promoting microorganisms increase resistance of seedling against adverse environmental condition which are possible causes of oak decline. The aim of this study was to determine and compare the effect of plant growth promoting rhizobacteria on growth parameters of Quercus brantii and Q. libanii in greenhouse condition. Seeds of Q. brantii and Q. libanii were inoculated by phosphate solubilizing bacteria which isolated from their natural habitat in Garaan Research station, Kurdistan, Iran. The experiment was conducted in a factorial design based on randomized complete block design with two main factors including species (two levels) and bacteria (five levels). At the end of the growing season, parameters of seedling growth like shoot length, collar diameter, dry mass of different organs and nutrient status including phosphorous, iron, magnesium, manganese and zinc concentration were determined. Oak seedling growth increased by bacteria depending on oak species as Q. libanii had better response in compared to Q. brantii. Inoculated bacteria increase seedling shoot length, collar diameter and dry matter. There was increase in phosphorous and other microelements concentration in inoculated seedling in compared to un-inoculated one. The bacteria acted differently as Pseudomonas putida and Bacillus subtilis had better efficiency. It seems inoculated Q. libanii with P. putida and B. subtilis have more growth and nutrient status making them suitable candidates in reclamation programs in order to combat oak decline.

کلیدواژه ها:

Reclamation ، Inoculation ، Growth ، Phosphorous ، Micronutrient