Department of Genetics and Plant Breeding, Palli Siksha Bhavana (Institute of Agriculture), Visva-Bharati University, Sriniketan, West Bengal, India.
Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran.
PLoS One. 2023 Jun 12;18(6):e0286975. doi: 10.1371/journal.pone.0286975. eCollection 2023.
Genetic variations are a crucial source of germplasm heterogeneity, as they contribute to the development of new traits for plant breeding by offering an allele resource. Gamma rays have been widely used as a physical agent to produce mutations in plants, and their mutagenic effect has attracted much attention. Nonetheless, few studies have examined the whole mutation spectrum in large-scale phenotypic evaluations. To comprehensively investigate the mutagenic effects of gamma irradiation on lentils, biological consequences on the M1 generation and substantial phenotypic screening on the M2 generation were undertaken. Additionally, the study followed the selected mutants into the M3 generation to evaluate the agronomic traits of interest for crop improvement. Seeds of lentil variety Moitree were irradiated with a range of acute gamma irradiation doses (0, 100, 150, 200, 250, 300, and 350 Gy) to induce unique genetic variability. This research focused on determining the GR50 value while considering seedling parameters and examining the status of pollen fertility while comparing the effects of the gamma irradiation dosages. The GR50 value was determined to be 217.2 Gy using the seedling parameters. Pollens from untreated seed-grown plants were approximately 85% fertile, but those treated with the maximum dosage (350 Gy) were approximately 28% fertile. Numerous chlorophyll and morphological mutants were produced in the M2 generation, with the 300 Gy -treated seeds being the most abundant, followed by the 250 Gy -treated seeds. This demonstrated that an appropriate dosage of gamma rays was advantageous when seeking to generate elite germplasm resources for one or multiple traits. Selected mutants in the M3 generation showed improved agronomic traits, including plant height, root length, number of pods per plant, and yield per plant. These investigations will contribute to a comprehensive understanding of the mutagenic effects and actions of gamma rays, providing a basis for the selection and design of suitable mutagens. This will facilitate the development of more controlled mutagenesis protocols for plant breeding and help guide future research directions for crop improvement using radiation-induced mutation breeding techniques.
遗传变异是种质异质性的重要来源，因为它们通过提供等位基因资源，为植物育种的新性状的发展提供了一个途径。伽马射线已被广泛用作物理诱变剂来产生植物突变，其诱变效应引起了广泛关注。然而，很少有研究在大规模表型评估中研究整个突变谱。为了全面研究伽马射线对兵豆的诱变效应，在 M1 代进行了生物学后果研究，并在 M2 代进行了大量表型筛选。此外，研究人员将选择的突变体跟踪到 M3 代，以评估对作物改良感兴趣的农艺性状。用一系列急性伽马射线剂量（0、100、150、200、250、300 和 350 Gy）照射兵豆品种 Moitree 的种子，以诱导独特的遗传变异性。这项研究的重点是确定 GR50 值，同时考虑幼苗参数，并在比较伽马射线剂量的影响时检查花粉育性的状态。使用幼苗参数确定 GR50 值为 217.2 Gy。未经处理的种子种植的花粉约有 85%是可育的，但用最大剂量（350 Gy）处理的花粉约有 28%是可育的。在 M2 代中产生了大量的叶绿素和形态突变体，其中 300 Gy 处理的种子最多，其次是 250 Gy 处理的种子。这表明，在寻找一个或多个性状的优良种质资源时，适当剂量的伽马射线是有利的。M3 代中选择的突变体表现出改良的农艺性状，包括株高、根长、每株荚数和每株产量。这些研究将有助于全面了解伽马射线的诱变效应和作用，为选择和设计合适的诱变剂提供依据。这将有助于开发更可控的植物诱变育种方案，并有助于指导利用辐射诱导突变技术进行作物改良的未来研究方向。
