Dr. Maryam Jafarkhani Kermani, Associated Professor of the Department of Cell and Tissue culture of ABRII, stated that her group succeeded in developing the technology of virus elimination and micropropagation of apple cultivars and rootstocks. She declared that in 2013, the highest amount of apple crop production was estimated to be approximately 3.44 million tons and a share of 19.22 percent of the total orchard productions in the country. Major apple producing provinces of Iran include; West Azerbaijan, East Azerbaijan and Tehran which produce more than 51 percent of the total apple yield. However, due to various bacterial, viral and pseudo-viral diseases the quality and quantity of apple production in the orchards have been reduced worldwide and also in Iran. Viruses essentially infect all plant tissues including meristems. Contamination is spread by transferring the virus from one infected plant's source to healthy plants by using infected equipment during pruning and gardening. Providing virus-free and genetically uniform plants through a micropropagation system is considered critical for establishing new healthy and uniform orchards.

To create healthy and genetically uniform orchards, it is necessary to establish plants in vitro conditions, eliminate the viruses and design a mass propagation protocol for each plant variety. During the stages of micropropagation, bacterial and fungi are usually eliminated; however, to eliminate viruses, viral elimination treatments are necessary. Virus detection is carried out prior to application of the treatments. To detect viruses, ELISA tests are used for the general diagnosis of viruses. While reverse polymerase chain reaction (RT-PCR) is used as a reliable and relatively simple tool for detecting low virus concentrations. One of the most common methods for virus elimination is the meristem culture, where the meristems of 0.2 to 0.7 mm in length are separated from the infected in vitro plantlets and cultured on specified culture media. The resulting plantlets (after three sub-culture) are tested for the presence of viruses. Thermotherapy, another common method of virus elimination is the treatment at high temperatures, where in vitro plants are subjected to temperatures of 37ᵒ C and above. Chemotherapy, treatment of virus infected tissues with chemicals such as ribavirin, is an alternative way of virus elimination. Both thermotherapy and chemotherapy are usually combined with meristem culture.

•         Virus elimination of commercial, endemic and rootstocks of apple

•         Establishment of pre-basic apple plant material

•         Propagation of basic plant material and establishment of nursery stocks

It is worth nothing that this technology presents the mass propagation protocol for various apple rootstocks and cultivars through tissue culture, gives the resources for production of virus- free apple varieties in mass numbers, replaces the old and low-yielding apple orchards with new and high yielding cultivars as well as increasing the quantity and quality of apples production in the country.