Tomatoes are usually grafted onto root stock which are resistant to a variety of diseases. but I quite happily increase my stock by taking cuttings, What I would like to know,is will the cuttings of grafted tomatoes still carry the resistance to the diseases.
I also take cuttings from my strongest/best producing plants in the early autumn, keeping them alive in a frost free environment over winter. I take further cuttings in the new year as soon as there is any growth large enough to do so. Gives me an early start with a tomato crop.. So my grafted tomatoes will have produce cuttings twice.