Zulfiqar Sana, Ishfaq Shumila, Raza Bukhari Sayyad Ali, Sajjad Muhammad, Akhtar Muhammad, Liu Dongcheng, Rahman Mehboob-Ur
Plant Genomics and Molecular Breeding Laboratory, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, 38000, Punjab, Pakistan.
Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Faisalabad, 38000, Punjab, Pakistan.
Heliyon. 2024 Feb 19;10(5):e26529. doi: 10.1016/j.heliyon.2024.e26529. eCollection 2024 Mar 15.
Reports on development of resilient wheat mutants to aphid infestation-causing heavy losses to wheat production in many parts of the world, are scanty. The present study aimed to identify genetic diversity of wheat mutants in terms of varying degree of resistance to aphid infestation which can help protect wheat crop, improve yields and enhance food security. Resistance response to aphid infestation was studied on newly developed 33 wheat mutants, developed through irradiating seed of an elite wheat cultivar "Punjab-11" with gamma radiations, during three normal growing seasons at two sites. Data on various traits including aphid count per plant, biochemical traits, physiological traits and grain yield was recorded. Meteorological data was also collected to unravel the impact of environmental conditions on aphid infestation on wheat plants. Minimum average aphid infestation was found on Pb--2725, Pb--2550, and Pb--2719 as compared to the wild type. High yielding mutants Pb--1323, Pb--59, and Pb--1272 supported the moderate aphid infestation. The prevailing temperature up to 25 °C showed positive correlation (0.25) with aphid count. Among biochemical traits, POD (0.34), TSP (0.33), TFA (0.324) exhibited a high positive correlation with aphid count. In addition, CAT (0.31), TSS (0.294), and proline content (0.293) also showed a positive correlation with aphid count. However, all physiological traits depicted negative correlation with aphid count, while, a very weak correlation (0.12) was found between mean aphid count and grain yield. In PCA biplots, the biochemical variables clustered together with aphid count, while physiological variables grouped with grain yield. Biochemical parameters contributed most, towards first dimension of the PCA (48.6%) as compared to the physiological variables (13%). The FAMD revealed that mutant lines were major contributor towards total variation; Pb--1027, Pb--1323, Pb--59 were found to be the most diverse lines. The PCA revealed that biochemical parameters played a significant role in explaining variations in aphid resistance, emphasizing their importance in aphid defense mechanisms. The identified mutants can be utilized by the international wheat community for getting insight into the molecular circuits of resistant mechanism against aphids as well as for designing new KASP markers. This study also highlights the importance of considering both genetic and environmental factors in the development of resilient wheat varieties and pave the way for further investigations into the molecular mechanisms underpinning aphid resistance in wheat.
关于培育对蚜虫侵害具有抗性的小麦突变体的报道很少，而蚜虫侵害在世界许多地区给小麦生产造成了巨大损失。本研究旨在确定小麦突变体在抗蚜虫侵害程度方面的遗传多样性，这有助于保护小麦作物、提高产量并增强粮食安全。在两个地点的三个正常生长季节，对通过用伽马射线辐照优良小麦品种“旁遮普 - 11”的种子而新培育的33个小麦突变体进行了抗蚜虫侵害反应的研究。记录了包括单株蚜虫数量、生化特性、生理特性和籽粒产量等各种性状的数据。还收集了气象数据，以揭示环境条件对小麦植株蚜虫侵害的影响。与野生型相比，在Pb - 2725、Pb - 2550和Pb - 2719上发现的平均蚜虫侵害最少。高产突变体Pb - 1323、Pb - 59和Pb - 1272能够承受中等程度的蚜虫侵害。高达25°C的环境温度与蚜虫数量呈正相关（0.25）。在生化特性中，过氧化物酶（POD，0.34）、总可溶性糖（TSP，0.33）、总游离氨基酸（TFA，0.324）与蚜虫数量呈高度正相关。此外，过氧化氢酶（CAT，0.31）、总糖含量（TSS，0.294）和脯氨酸含量（0.293）也与蚜虫数量呈正相关。然而，所有生理特性与蚜虫数量呈负相关，而平均蚜虫数量与籽粒产量之间的相关性非常弱（0.12）。在主成分分析双标图中，生化变量与蚜虫数量聚集在一起，而生理变量与籽粒产量分组在一起。与生理变量（13%）相比，生化参数对主成分分析的第一维度贡献最大（48.6%）。因子分析表明突变系是总变异的主要贡献者；发现Pb - 1027、Pb - 1323、Pb - 59是最具多样性的品系。主成分分析表明生化参数在解释蚜虫抗性变异方面发挥了重要作用，强调了它们在蚜虫防御机制中的重要性。国际小麦界可以利用所鉴定的突变体来深入了解抗蚜虫机制的分子回路，以及设计新的竞争性等位基因特异性PCR（KASP）标记。本研究还强调了在培育抗逆小麦品种时考虑遗传和环境因素的重要性，并为进一步研究小麦抗蚜虫的分子机制铺平了道路。
