(a) A large-scale propagation of desired crop in a short duration can be carried out with the help of micropropagation or tissue culture technique. The main steps of tissue culture technique are as follows: 

(i) Preparation of nutrient medium : A suitable nutrient medium is prepared and transferred into containers under aseptic conditions. 

(ii) Selection of explants : Explants are taken preferably from the meristematic regions (apical or axillary buds or the modal sections) of the desired crop plants. 

(iii) Sterilization of explants : The explants are surface sterilized by disinfectant like sodium hypochlorite and then washed by sterile distilled water. 

(iv) Inoculation : Inoculation (transfer) of explants into previously sterilized nutrient medium under aseptic conditions. 

(v) Incubation : The cultures are kept for incubation in the growth chamber under suitable cultural conditions. 

(vi) Regeneration : After incubation for a few days the explants give rise to an undifferentiated mass of cells called callus from which in due course of time a number of plantlets come out. 

(vii) Hardening : The regenerated plantlets are acclimatized gradual exposure to the environmental conditions 

(viii) Plantlets Transfer : The plantlets are transferred to green House or field after their acclimatization (Hardening). 

(b) Somatic hybrids are obtained by somatic hybridization a process of fusing the protoplast of two different somatic cells obtained from different varieties or species of plants under optimal cultural conditions. The main steps of somatic hybridization are 

(i) Isolation of single cells from two different plants having desired characteristics or traits. 

(ii) Digestion of their cell wall with the help of enzymes like cellulase and pectinases.

(iii) Isolation of naked protoplast. 

(iv) Fusion of two protoplasts by spontaneous fusion or by induced fusion. 

(v) Growth of hybrid protoplast : The hybrid protoplast is further grown to form somatic hybrid. A new hybrid plant named as pomato has been developed by this technique. This has the characteristics both tomato and potato.