13. An authorisation under paragraph 11 may—
(a)in relation to potato production, specify that only certified seed potatoes or mini-tubers or micro-plants derived from officially tested sources may be used in the production;
(b)in relation to tomato production, specify that only seed which meets the requirements of Directive 2000/29/EC or, if vegetatively propagated, tomato plants produced from seed which meets the requirements of Directive 2000/29/EC and grown under official control, may be used in the production;
(c)prohibit any irrigation or spraying programme at the place of production;
(d)specify how any irrigation or spraying programme at the place of production must be carried out for the purpose of preventing the spread of Potato brown rot.