If no fruits, no seeds, probably you have to use tissue culture method by using tissues to propagate it. Since you have no seeds, you cannot use sterilized seeds (or parts from seedlings, such as cotyledons, hypocotyls...) for tissue-culturing. You have to find out which tissue parts of an adult tomato (Micro-Tom) best suit for tissue-culturing (regeneration).
I browse through the two papers (by Sun and by Khuong) attached by Arvind Singh. Both used explants from sterilized-seed germinated seedlings. You need to find a protocol using tissues from soiled plants for tissue-culturing.
Those soiled tomato plants you have-- are they transgenic?
Some plants derived from genetic transformation can be sterile (no seed sets). I wonder that the plants regenerated from your soiled sterile tomato plants can become fertile!?
If the requirement is to generate few more plants for analysis etc. from a single plant, then the following vegetative propagation method can be used.The simplest way to generate many new plants from tomato is to induce rooting in branches cut from the main plant. Branches of about 4-5 inches can be cut and placed in a conical flask (250-500 ml) containing water, the cut end has to be immersed in water. Within a week roots will emerge and after few more days individual plants can be transplanted on to field or pots. Water in the container needs to be changed once in 3-4 days.We routinely follow this method to obtain more plants for various analysis from selected plants which saves time instead of waiting for the fruits to ripen to harvest seeds.
Naveed Mushtaq, I am not aware of any research articles on the procedure of vegetative propagation of tomato as such, as this is a relatively insignificant procedure we have no publications detailing this procedure, all it requires is changing water once in 3-4 days to, minimize algal growth, we use this method to multiply cultivated tomato with near 100% success. i have not used microtom, however should work in microtom also. Alternatively, another method would be grafting, which also is widely practiced in tomato on brinjal (egg plant) root stock. I would mail you photographs of the setup for rooting of tomato shoots. Hope it helps.
Manamohan Maligeppagol is right, see the link below about 'Cutting propagation of tomato plants". This will be much easier than using tissue-culturing for propagation.
Title: How to Start Tomato Plants from Cuttings [http://www.vegetablegardener.com/item/4207/how-to-start-tomato-plants-from-cuttings]
From the link:
I. "The tomato plant, in particular, lends itself easily to cutting propagation because even the cells in its stems can become roots."
II. "How to start tomato plants from cuttings:"
1. First, you want to fill your 4 inch containers with the dampened potting soil.
2. Take the 6 inch cuttings and clip off any flowers or buds. Clip off the bottom leaves leaving only two leaves on the cutting.
3. Make a hole in the potting soil with the pencil–you don’t want to be trying to shove the soft stem into the soil.
4. Put the cuttings into the soil and press the soil up around them. Make sure the places where you cut off the lower leaves is buried.
5. Keep them in a warm place, but shaded form any direct sun. I prefer a kitchen window to protect them from the elements, but where ever they are protected is fine.
6. Leave them moist and in this spot for about a week.
7. You’ll then want to gradually expose them to stronger light until they are in the sun for most of the day. This may take another week.
8. At this point you can transplant them into the garden bed or maybe a large pot, where they will continue to grow and produce some lovely tomatoes for you! This is the best time to give the baby tomato plants to friends so they can start them in their gardens right away.