الفهرس | Only 14 pages are availabe for public view |
Abstract SUMMARY The present study aimed to study the relationship between plant tissues in different media, calli growth behaviour and their proliferai ton with their genetical and cytological behaviour using three ~ mays cultivars; one local; Giza 2 (G2), and two American; PI 451690 and 451694. The results obtained could iDe summarized as follows: 1- The Egyptian cultivar G2 hypocotyl explants grown on MS medium supplemented with 10 mg 1M/I, gave quite different growth behavi.our. 2- The cytological examination for this group of the hypocotyls, which were able to differentiate on this medium, i.•e., MS + 10 mg lAA/l showed mitotic index reached to 38.6% which is higher than that for the control plants which reached to 23 .•6%- 3- Use of different media, gave different growth behaviour and differentiation.. In many instances, the mitotic index diminished to a greater extent. 4- The cytological investigations showed many types of chromosomal abnormalities in the different media supplemented with different hormones • • - 133 - 5- Similar results were obtained using explants, e.g., root tips for instance. different 6- Seeds growth on MS medium supplemented with different concentrations of 2,4_0 showed big differences in growth behaviour and cytological investigations. 7- The mitotic index was reduced to a great extent with wide variations in chromosomal aberrations. 8- The mature embryos did not N6 medium supplemented with 2,4_0/1 and 25 roM L. proline. show any response on either 1 mg or 5 mg 9- The mature embryos on N6 medium supplemented with 10 mg IAA/1 and 1 kg Kin/1 gave only one survived embryo showing four thin roots and a stem with one abnormal leaf. The cytological examinations showed large number of nucleoli whether outside or inside the nucleus. 10- Different results for growth behaviour and cytological examination, from those of G2, were obtained for the cultivar PI 451690. Also the American cultivar PI 451694 gave different behaviour for growth and cell divisions with various types of chromosomal aberrations. |