Division of Genetics, Indian Agricultural Research Institute, Delhi-12
2Present address: Regional Research Laboratory (C.S.I.R.), Sanat Nagar, Srinagar-5, (J & K).
3Present address: C/o The Ford Foundation, 1, Sharia Osiris, Garden City, Cairo, U.A.R.
1Part of the thesis submitted by B. K. BHAT in partial fulfilment of the requirement for Ph.D. degree of I.A.R.I., New Delhi.
Cytoplasmic variation in closely related varieties coming from the same geographic region was studied by reciprocally crossing each of the three varieties of maize with another unrelated variety. Observations were taken on grain yield, maturity, plant height and ear height. The interaction of the four sets of quantitative genes with the three cytoplasmic types varied from cross to cross and character to character. Even the varieties with a common origin did not interact identically for all quantitative characters thereby revealing that their cytoplasms were different. Indeed, the cytoplasms of all the varieties were different from one another.
