The higher plants are normally diploid, with two sets of chromosomes in their somatic cells. Their haploids (with one set of chromosomes) arise in nature by parthenogenesis due to malfunction in the normal sexual process. However, such events are extremely rare and unpredictable. In 1964, two Indian scientists, Guha and Maheswari, observed that in cultured anthers of Datura innoxia some of the microspores, instead of following the normal gametophytic mode of development, formed sporophytes (Androgenic plants).
As expected, those sporophytes were haploid. This report caused much excitement because of the considerable importance of haploids in genetics and plant breeding. To-date androgenic haploids of over 200 species, including many major crop plants (Cereals, Brassica spp, tomato and potato), have been raised through anther and/or isolated pollen culture.