A 2px padding is probably too small to do anything noticeable. Plus doing it that way below would be changing the padding on ALL tds.
If you only want to affect the padding for that one td, you can either give it a class and define specific CSS for it in the stylesheet, OR you can add an inline-style along with your others - about 10px on the left and right look like they would do it;
Code:
<td style="vertical-align: top; text-align: justify; width: 850px; padding-right: 10px; padding-left: 10px;" class="">How do you marry a niche rural agri brand with the world of social media? With an interactive, informative and social facebook page! The Agrimark facebook page has grown to a community of almost 10 000 members in just 20 months and is growing by the day.</td>
Bookmarks