Unraveling molecular processes involved in adventive polyembryony towards genetic engineering for fixation of heterosis
About the Project
The overall objective of the National Agricultural Innovation Project (NAIP) of Indian Council of Agricultural Research (ICAR) is to facilitate an accelerated and sustainable transformation of the Indian agriculture, so that it can support poverty alleviation and income generation through collaborative development and application of agricultural innovations by the public organizations in partnership with farmers, the private sector and other stakeholders. The objective of the NAIP under the Component 4 is to build capacity to undertake basic and strategic research in frontier areas of agricultural sciences and also generate basic information on some of the fundamental processes relevant to agriculture. Present project is funded by the NAIP to undertake basic studies on polyembryony with an ultimate aim to fix heterosis.
In the current scenario of limiting land and other vital resources, productivity enhancement appears to be the only option available for meeting food demands of the future. Production of hybrids in crops like rice, corn, pearl millet, sunflower, cotton and several vegetable crops amply testify the importance of heterosis breeding in increasing the productivity of crops, but various technical constraints limit the exploitation of heterosis breeding in several other crops. Moreover, hybrids seeds are expensive and need to be purchased every time making it beyond the reach of resource-poor Indian farmers. It is widely believed that any technology that can fix heterosis has the potential to usher in another green revolution. Apomixis is an asexual mode of reproduction through seeds where embryos develop parthenogenetically from unreduced egg and are an exact genetic replica of the mother. Thus if apomixis is engineered into crops, heterosis can be fixed directly. Apomixis, however, could not be exploited so far mainly because of very limited understanding of apomixis at molecular level.
At present, the world over efforts are directed at understanding molecular basis of gametophytic apomixis. Gametophytic apomixis involves a major shift in the normal reproductive process to generate genetically identical progenies. The uniqueness of the present project is its focus on an alternate route of apomixis via polyembryony. In apomictic polyembryony multiple genetically identical embryos are produced in a seed directly from somatic cells. In majority of such cases (e.g. citrus) polyembryony occurs in addition to the normal sexual hybridization. Thus, polyembryony being an add-on feature could perhaps be more amenable for genetic engineering.
