Characterization of rhizobacteria secondary metabolites on maize (Zea mays) in marginal land

Abstract

Maize is one of the strategic food crops and has economic value and could be developed because of its position as the main carbohydrate and protein source after rice. This could be a reference for us to increase maize cultivation, seeing the role of maize is quite large, and the availability of maize is less stable every year. maize can grow optimally on productive land and marginal land, but at this time more productive land is used for rice production. One alternative for maize production is on marginal land especially dryland. The main problem in dryland is limited water. One way to overcome this is by inoculating Rhizobacteria which can increase the growth and resistance of maize to drought. Rhizobacteria possess tremendous potential for modulating the physiological response to water deprivation, thus ensuring plant survival under such stressful conditions. The research aimed to find rhizobacteria have secondary metabolite for resistance to drought. Rhizobacteria exploration and secondary metabolite isolation was conducted at University of Muhammadiyah Malang. The research results have obtained 10 isolates capable of synthesizing extracellular secondary metabolites: osmoprotectants, phytohormones, and organopesticides that can be used by plants. The results of the analysis by GS-MS (Gas Chromatography-Mass Spectrometry) rhizobacteria showed that three compounds were synthesized. The osmoprotectants compound synthesize ware found namely: (a) (2E)-3,7-dimethylocta-2,6-dienal 16.66%;(b) (E)-hept-2-enal12.55%;(c)2-methylsulfanylethanamine 5.34%; (d) 1,3,5-trimethoxybenzene 4.42%. It is also capable of synthesizing phytohormones: (a) cinnolino [4,3-b] quinoxaline 6.00%; (b) 1-methyl-2-phenylindole 5.90%; (c) 1H-Indole 3.64%; (d) N-2-Fluorenylperfluorpropionamid 3.02%. These rhizobacteria were also able to synthesize: (a) 2-chloro-4-methoxy phenol 11.32%; (b) (E)-non-2-enal 9.87%; (c) 4-chloro-2,6-dipyridin-2-ylpyridine 7.07%; (d) 2-(4-chlorophenyl) hexane nitrile 6.45%. The Osmprotectant compounds aim to protect cells from drought conditions, phytohormones to stimulate plant growth and organopesticides to overcome pests and diseases.