All depends on what's your final goal.

For simply identifying metabolites use: 1H, 1H-1H COSY. 1H-1H TOCSY and 1H-13C HSQC (this is the bare minimum you should collect. Use the 2D spectra for assignments). HSQC is essential, along with either TOCSY or COSY. Any standard instrument can run these experiments.

You will have to use some kind of database matching for your assignments (Bruker Amix or ACDLabs Spectrus DB.

If you have lots of samples and want to do statistical analysis (such as PCA), just use 1H NMR. There are lots of papers on this.

In addition to the previous comments I would suggest to use also HMBC experiments to reveal also quaternary carbons.

I agree very much with both Rudraksha and Alessandro in using

1H, 1H-1H COSY. 1H-1H TOCSY and 1H-13C HSQC (this is the bare minimum you should collect. Use the 2D spectra for assignments). HSQC is essential, along with either TOCSY or COSY. Any standard instrument can run these experiments.

and HMBC

Thank you all

I have lots of samples and want to do statistical analysis so according to Rudraksha Dutta Majumdar recomandation it is better to I use H-NMR. I do not know how many metabolite will identify  by use of our NMR. IS its power (450 MHz) sufficient for NMR based metabolomics? i hope it could identify at least 40-50 polar and non-polar metabolites.

Dear Mohsen,

As you decided  doing H-NMR. Find in attached a paper on: 1H NMR-based metabolomic analysis of polar and non-polar earthworm metabolites after sub-lethal exposure to phenanthrene

Brian P. Lankadurai • David M. Wolfe •

Melissa L. Whitfield A ° slund • Andre´ J. Simpson •

Myrna J. Simpson

Metabolomics (2013) 9:44–56

DOI 10.1007/s11306-012-0427-3

Hoping to be helpful

Best wishes

Dear Talaat I. El-Emary, 

Thank you for attached paper. It is a good article which answer my questions.

Best

Dear Mohsen,

I wish you good luck

Dear Lixiang Zhai,

Thank you 

How to analyzed NMR data....and which softwere is best to identified the unknown metabolites in plant leaf samples..Please suggest.

Dear Biswajit,

I analyzed my NMR spectra and identified metabolites by mestreNova, but if you know software packages for identification of unknown metabolites please share their name.

Thanks

A couple of special issues on plant metabolomics were published in the journal Phytochemical Analysis since 2010, which you might want to consult.