Induction of Androgenesis as a Consequence of Wide Crossing in Chickpea

Androgenesis was observed in a wide cross of Cicer arietinum × C. pinnatifidum. Hybrids between C. arietinum × C. pinnatifidum were obtained after rescuing the hybrid embryos in vitro. The hybrids were initially devoid of any chlorophyll pigment and were albinos. Upon continuous culture in a zeatin-rich medium and in the presence of light, the hybrids turned semi-green. Hybrid shoots were grafted to chickpea rootstocks to obtain hybrid plants. None of the hybrid plants flowered. When the nutrient solution with zeatin (1.0 mg/litre) was added, flower buds were observed on hybrid plants. Flower buds were fragile, albino to semi-green, but with normal morphology. Anthers were squashed in acetocarmine and divisions were observed in some of the microspores. The number of divisions varied from 4 to 6. Adding nutrient solution with zeatin (1.0 mg/litre) to in vivo-grown chickpea plants did not induce division in the microspores. Sixteen hybrid plants were obtained. The number of microspores/pollen grains in an anther varied from 11 to 151, compared to more than 500 pollen grains in cultivated chickpea. The number of pollen grains that had undergone microsporogenesis and induction of androgenesis varied from plant to plant. Percent androgenic pollen grains varied from 0 to 100%. Plant nos. 8, 11 and 12 did not have any androgenic pollen grains, whereas in plant nos. 14 and 16, all the pollen grains were androgenic or had multicellular microspores. The number of cells in multicellular microspores in plant nos. 14 and 16 varied from 8 to 10 unlike 4-6 cells in multicellular microspores in other hybrid plants that had androgenic microspores. This is the first report of the production of multicellular microspores as a result of wide crossing.