Potentials of protoplast culture work in agriculture

Abstract

During a short span of the last four years there have been exciting developments in the field of protoplast culture and somatic hybridization.Enormous interest and enthusiasm was shown by plant scientists at the 'International Colloquium on Protoplasts and Fusion of Somatic Plant Cells', and 'Third International Symposium on Yeast Protoplasts' held in 1972 at Versailles (France) and Salamanca (Spain), respectively. At present, large quantities of protoplasts can be enzymatically isolated, and when cultured they regenerate a wall and divide to give rise to a clone of homogenous callus tissue. By manipulation of nutritional and physical conditions this tissue can be induced to differentiate into both haploid and diploid plants. The protoplasts can also be induced to fuse with one another, the fused product can be cultured, and made to regenerate into a somatic or 'parasexual hybrid'. The protoplasts take up micro-and macromolecules, viruses, bacteria, and genetic materials like DNA and nuclei, and serve for the transformation and cell modification studies. Isolated chloroplasts have also been transplanted into albino protoplasts and green plants obtained.The protoplast culture work has unlimited potentialities for plant improvement. It is already being used as a novel research tool by the physiologists, virologists, molecular biologists, geneticists, and for morphogenetic studies. The work could have far-reaching implications in agricultural research as in future (1) the regeneration of somatic hybrids from fused protoplasts of sexually incompatible or distantly related plants, (2) the introduction of nitrogen-fixing bacteria and blue-green algae into non-legumes specially the cereals, (3) the induction of disease-resistance in a crop by the incorporation of a selective genome into the protoplast, (4) the induction and easy detection of mutations in haploid protoplasts, (5) the transplantation of 'foreign chloroplasts' into crop plants with inefficient photosynthetic system, (6) culture of protoplasts to raise clones for vegetative multiplication and also for genetic diversity and (7) insertion of a part or complete genome by transgenosis, cell modification, and nuclear transplantation could replace or at least help to modernize some of the conventional practices used for plant improvement. To get this gigantic task done a close collaboration between various disciplines of plant sciences is desired, and the resources pooled together to get the maximum benefits of the facilities and the talent available. A great deal of responsibility lies specially with the geneticists and plant breeders who will eventually deal with the ultimate product. These above mentioned possibilities are by no stretch of imagination meant to be any substitute for the present day plant breeding practices, but they are certainly new valuable tools which can be exploited.

A CRISPR/dCas9 toolkit for functional analysis of maize genes

“…Protoplasts, live plant cells from which the cell wall has been removed, have proven to be a tractable system for a wide range of studies, including biochemistry, cell dedifferentiation, as well as genetic manipulation [21][22][23][24]. Methods for transient transgene expression in protoplasts are relatively quick and straightforward, making them a useful system when stable transgenic plants are unavailable or a high-throughput system is needed [24,25].…”

Regeneration of genetically diverse plants from tissue cultures of forage grass — Panicum sps

“…In previous studies, the successful use of different in vitro methods for the induction of genetic variability in various crops through the culturing of hybrid embryos (BAJAJ et al ., 1978a), endosperm (BAJAJ et al ., 1980), isolated protoplasts and pollen (BAJAJ et al ., 1978b), in vitro fertilization (BAJAJ, 1979), and somatic hybridization (BAJAJ, 1974) was demonstrated . Although the differentiation of complete plants from callus cultures has been routinely obtained in a large number of plant species, the induction of reproducible regeneration in cereals and grasses is still a challenge (YAMADA, 1977 ;GREEN, 1978) .…”

Breeding Apple Rootstocks

“…These include selection of natural variants and induced mutants, ploidy alteration, protoplast fusion, and recombinant DNA (Bajaj 1974;Pandey 1978). Research with some of these methods is only now beginning to be done on apple.…”