Article 621 of Civil Code

1 - If it becomes impossible for the lessee to prepare the land for cultivation or sow it, or if all or most of the seed perishes, due to an external cause beyond his control, he shall be discharged from all or part of the rent, as the case may be, unless an agreement provides otherwise. 2 - If the entire crop perishes before harvesting due to an external cause beyond the lessee's control, he may request remission of the rent. 3 - If part of the crop perishes and its destruction results in a substantial reduction in the land's yield, the lessee may request a reduction of rent proportionate to the reduction in the land's yield.