Invoke method of specific members basetype

I've got a problem invoking with these classes:

class Container 
{
    IARepo a = new ARepo();
    IBRepo b = new BRepo();
    ICRepo c = new CRepo();
}

interface ARepo:Repo<ABase>, IARepo 
{
}

interface IARepo: IRepo<ABase> 
{
}

interface IRepo<T> 
{
    GetAll();
}

class Repo<T> : IRepo<T> 
{
    GetAll();
}

I have to iterate over a, b and c to find a specific member of the container and call GetAll() via reflections on it.

What i do at the moment is:

PropertyInfo[] properties = typeof(container).GetProperties();
foreach (PropertyInfo property in properties)
{
    if (property.Name.Equals(NAME OF REPOSITORY))
    {
        //Access GetAll() for the specified property
    }
}

Using MethodInfo I can't access GetAll() as it is declared in a base type of the member.

Could you enlighten me on how to do it and why sour solution works?

Thanks in advance!