ARC-Small Grain Institute, An Institute of the Field Crops Division, Private Bag X29, Bethlehem, 9700, South Africa.
Graduate Mastery, Boskruin View Office Park, 181 Girdwood Avenue, Bush Hill, Randburg, 2154, South Africa.
Radiat Environ Biophys. 2023 May;62(2):195-212. doi: 10.1007/s00411-023-01026-3. Epub 2023 Apr 19.
The study aim was to determine the optimal gamma irradiation dose for mutation breeding in Triticum turgidum ssp. durum L. Root, shoot and seedling growth, as well as the efficiency of energy conversion into growth were determined to examine the growth retardation effects of gamma irradiation that are the result of DNA damage (bridges, ring chromosomes, micronuclei, incomplete mitosis) in Triticum turgidum ssp. durum L. The kernels were irradiated with doses of 50, 150, 250 and 350 Gy using a Cobalt gamma-ray source. The kernels were placed in germination paper at 25 °C to grow for a 132 h period for the determination of shoot and root growth and the efficiency of energy conversion into growth. Root tips were collected and fixated over a 47.5 h growth period for the determination of the chromosomal abnormalities and incomplete mitosis. The control differed highly significantly (p < 0.01) from irradiated samples at all doses in root growth and from 250 to 350 Gy samples in shoot growth and the efficiency of energy conversion into growth. There was a highly significant (p < 0.01) increase in the number of bridges and micronuclei between 50 Gy samples and samples irradiated with the higher irradiation doses while 50 Gy samples differed only from 250 and 350 Gy samples regarding ring chromosomes and interphase cells with incomplete mitosis. Root and seedling growth on the one hand and the efficiency of energy conversion into growth on the other were found to be measuring different effects of gamma irradiation on plant growth. The latter was used for the determination of the optimal dose for mutation breeding as 155.52 Gy.
本研究旨在确定对硬质小麦（Triticum turgidum ssp. durum L.）进行突变育种的最佳伽马辐射剂量。通过测定根、茎和幼苗的生长以及能量转化为生长的效率，来研究伽马辐射导致的 DNA 损伤（桥、染色体环、微核、不完全有丝分裂）对硬质小麦生长的抑制作用。用钴伽马射线源对麦粒进行 50、150、250 和 350 Gy 的辐照。将麦粒置于发芽纸上，在 25°C下培养 132 小时，以测定茎和根的生长以及能量转化为生长的效率。在 47.5 小时的生长周期中收集根尖并进行固定，以测定染色体异常和不完全有丝分裂。在根生长方面，所有辐照剂量的对照组与辐照组差异均极显著（p<0.01），在茎生长和能量转化为生长的效率方面，250 和 350 Gy 组与对照组差异极显著（p<0.01）。50 Gy 组与较高剂量辐照组之间的桥和微核数量显著增加（p<0.01），而 50 Gy 组与 250 和 350 Gy 组之间的染色体环和有丝分裂间期细胞的不完全有丝分裂仅存在差异。根和幼苗的生长以及能量转化为生长的效率被发现是衡量伽马辐射对植物生长的不同影响的指标。后者被用于确定突变育种的最佳剂量为 155.52 Gy。
