Induction of Water-Deficit Tolerance in Rice through Gamma Mutagenesis

2026-10-09T12:04:19+00:00

Rice is a strategic crop essential for Egyptian national food security; however, climate change and escalating water scarcity pose severe threats to its sustainable production. From this point, gamma rays with its safe doses were used to genetic improvement in the Egyptian rice cultivar (Sakha 102) and for elicitation five rice mutants classified as highly drought tolerated besides, its high yielding. The six rice accessions were evaluated across two growing seasons under normal and drought conditions. Yield components, physiological and biochemical attributes besides, water stress tolerance indices were the most important parameters tested under both treatments for screening the highest rice genotypes tolerated to drought stress under stress conditions. Results indicated that significant genetic variability (P < 0.01) was observed for all physiological and yield traits. Furthermore, drought stress severely
reduced yield components, particularly in the local cultivar "Sakha 102" (DSI > 1.87; YR: 0.27). Conversely, induced mutagenesis significantly improved drought resilience. Also, mutant 5 demonstrated superior tolerance, maintaining the highest grain yield (51.68 g) and 1000-grain weight (36.97 g) under stress by maximizing glycine betaine (77.68) and trehalose (60.45) accumulation. As
well, strong positive correlations were confirmed between osmoprotectants and yield attributes under stress, notably between proline and 1000-grain weight (r = 0.96). Further, high broad-sense heritability (> 70%) coupled with high genetic advance (18.59% - 26.45%) for grain yield under stress confirmed the governance of additive gene action. Ultimately, these findings identify Mutant 5 as a high-potential donor line and validate biochemical osmoprotection as a reliable selection criterion, offering a vital genetic tool to secure future rice production amidst future climatic challenges like high level of drought stress.

Biological and Physical Control Measures to Manage White Rot Disease Incidence in Onion and Garlic under Natural Field Conditions

2026-10-23T10:28:32+00:00

White rot caused by the soil borne fungus Stromatinia cepivora (Berk.) Whetzel, is the most destructive disease affecting onion (Allium cepa L.) and garlic (Allium sativum L.) crops in Egypt and worldwide. Therefore, the present investigation aimed to evaluate the efficacy of soil solarization alone or integrated with bio-control agents, in controlling white rot disease incidence in onion and garlic crops as well as their resulting yield. The data obtained revealed significant reduction and increase in yield for garlic and onion crops when cultivated using treated seeds or transplants with biocontrol agents, followed by planting in solarized soil and subsequent cultivation in solarized soil alone. The garlic bulb-seeds immersed in growth suspension of P. oxalicum; B. pumilus followed by B. subtilis revealed the lowest disease incidence. Meanwhile, high records of disease incidence were recorded in un-solarized soil. Furthermore, the treatment of bio-agents combined with soil solarization resulted in a significant increase in garlic bulb yield compared with plants grown in un-solarized soil. Onion plants showed similar results concerning disease incidence and harvested yield. The current study aims to utilize the hot weather months in Egypt to apply soil mulching technique for controlling serious soilborne plant pathogens. This can be done either alone or in conjunction with biological agents as part of an integrated pest management program.

Middle East Journal of Agriculture Research

Induction of Water-Deficit Tolerance in Rice through Gamma Mutagenesis

Biological and Physical Control Measures to Manage White Rot Disease Incidence in Onion and Garlic under Natural Field Conditions