EMS Induced Karyomorphological Variations in Maize (Zea mays L.) Inbreds

Chemical mutagen induced chromosomal variations were broadly observed from the point of view of understanding the mechanics of EMS induced anomalies and biological dosimetry in Zea mays L. Seeds of 6 inbred lines of maize, i.e. CM-135, CM-136, CM-137, CM-138, CM-142, and CM-213 inbreds, were first presoaked in distilled water and then these seeds were treated with 0.5% solution of EMS for 3 durations, i.e. 3, 5, and 7 h, and genetic segregations were carefully observed. During the present investigation, through EMS treatment, many chromosomal anomalies, namely precocious movements, stickiness, univalents, bridges, laggards, multivalents etc., were induced in all the inbred lines of maize. Higher frequencies of chromosomal anomalies were displayed at the maximum dose (7 h) of treatment in all the inbred lines of maize. Maximum chromosomal anomalies were observed in CM-213 (i.e. 22.92%) but inbred CM-138 displayed better responses in all the morphological parameters at the maximum dose (7 h) of EMS treatment. However, CM-142 was found to be the most suitable inbred line for induced mutagenesis since it registered minimum chromosomal damage with maximum variability.

EMS Induced Karyomorphological Variations in Maize (Zea mays L.) Inbreds

Chemical mutagen induced chromosomal variations were broadly observed from the point of view of understanding the mechanics of EMS induced anomalies and biological dosimetry in Zea mays L. Seeds of 6 inbred lines of maize, i.e. CM-135, CM-136, CM-137, CM-138, CM-142, and CM-213 inbreds, were first presoaked in distilled water and then these seeds were treated with 0.5% solution of EMS for 3 durations, i.e. 3, 5, and 7 h, and genetic segregations were carefully observed. During the present investigation, through EMS treatment, many chromosomal anomalies, namely precocious movements, stickiness, univalents, bridges, laggards, multivalents etc., were induced in all the inbred lines of maize. Higher frequencies of chromosomal anomalies were displayed at the maximum dose (7 h) of treatment in all the inbred lines of maize. Maximum chromosomal anomalies were observed in CM-213 (i.e. 22.92%) but inbred CM-138 displayed better responses in all the morphological parameters at the maximum dose (7 h) of EMS treatment. However, CM-142 was found to be the most suitable inbred line for induced mutagenesis since it registered minimum chromosomal damage with maximum variability.

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