Cycological Studies on popcorn( Zea mays var praecox start)
Cycological Studies on popcorn( Zea mays var praecox start)
| dc.contributor.author | Abdu, Muhammad Gali | |
| dc.date.accessioned | 2014-02-06T12:08:03Z | |
| dc.date.available | 2014-02-06T12:08:03Z | |
| dc.date.issued | 2000-10 | |
| dc.description | Thesis submitted to postgraduate school in partial fulfillment of the requirement of the award of master of science degree in Biology of the Ahmadu Bello University Zaria M.sc. BIOLOGY October 2000 | en_US |
| dc.description.abstract | Two strains (A and B) of inbred line of popcorn seeds (Zea mays var. praecox Sturt.) were used in the first trial and another strain (C) of popcorn was used in the second trial and raised to maturity, in the departmental garden. Inflorescences were collected from the first two strains for cytological study of meiosis on the 53rd, 55th, 57th and 59th days after sowing and at 6.00am, 9.00am. 12.00noon, 3.00pm and 6.00pm each day. In second trial, anthers from the young unopened spikelets were selected and pretrealed with various concentrations of colchicine at 0.05, 0.1 and 0.15 per cent, for time periods of 1, 2 and 4 hours respectively. Results of the investigation demonstrated that behaviour at meiosis in both the two strain was normal. Meiosis advanced linearly with the plant-ages. There was no correlation between interphase stage and all the other stages of meiotic divisions. Stages of the first division are highly correlated with one another but are less correlated with the stages of the second division while the stages of the second division are also highly correlated with one another. Similarly, the stages of the second division were influenced by the times of fixation and the ages of the plants. The proportions of the number of the pollen mother cells (PMCs) at different times of fixation has shown that the frequency of the interphase cells and the stages of the first division were more in the morning and the stages of the second division were more predominant in the evening which indicated that the interphase cells undergo meiotic division as (vii) the day passes and by the evening time most would have completed the second meiotic division. The data obtained on the effects of colchicine in arresting cell division at metaphase using another strain of popcorn (C) showed that the frequency of the chromosomal abnormalities was directly proportional to dose and duration of treatment. Treatments led to accumulation of more cells in meiosis I than meiosis II. Arrest of cells at metaphase I and metaphase II was another significant effect observed. Several meiotic irregularities with variable frequencies observed at metaphase include sticky chromosomes, sticky disoriented/non-oriented chromosomes, equivalents, bivalent s as well as univalent s and laggards. The most frequent aberration observed at phase were chromosome bridges. Other meiotic irregularities include unequal separation, laggards and equivalents which were observed at phase. In the control plants, meiosis had normal stages with insignificant deviations | en_US |
| dc.identifier.uri | http://hdl.handle.net/123456789/497 | |
| dc.language.iso | es | en_US |
| dc.subject | Cytological, | en_US |
| dc.subject | Studies | en_US |
| dc.subject | Popcorn | en_US |
| dc.title | Cycological Studies on popcorn( Zea mays var praecox start) | en_US |
| dc.type | Thesis | en_US |