Rice Genomics and Genetics 2024, Vol.15, No.1, 19-27 http://cropscipublisher.com/index.php/rgg 20 provide scientific basis for formulating corresponding agricultural management measures and ultimately achieve the goal of improving rice drought resistance. This study will systematically explore the response mechanisms of rice roots and leaves under drought conditions, which not only helps to enhance our understanding of rice drought resistance, but also provides concrete and strong support for addressing the challenges of global climate change to food security. By deeply analyzing the adjustment strategies of rice roots and leaves under drought stress, we are expected to provide innovative solutions for future rice breeding and agricultural production. 2 Drought Response of Rice Roots 2.1 Adjustment of Root Structure In the context of drought pressure on rice, its root system exhibits a series of complex and targeted changes to cope with water scarce environments. Firstly, it is worth noting the changes in root morphology of rice under drought conditions. Research has shown that rice can significantly adjust its root structure in water deficient environments. The length of the root system may increase in order to search deeper for water sources in the soil, while the overall biomass and surface area of the root system may also change to improve the efficiency of water absorption (Bartlett et al., 2022). The morphological adjustment of rice root system is not an isolated behavior, but a part of its growth adaptation strategy. For example, drought stress is one of the common environmental pressures during rice growth, and plants adapt to this challenge by adjusting their root structure. When facing drought conditions, rice roots exhibit significant adaptive changes, with one significant adjustment being the formation of root sheaths. The formation of root sheaths is considered a strategy for plants to cope with water stress, providing a protective mechanism by wrapping the root tips to slow down water loss. This structural adjustment is an important physiological response of rice to drought environments (Abdalla et al., 2021). However, the formation of root sheaths is accompanied by a decrease in plant biomass. Although the root sheath helps to slow down water loss to a certain extent, it also has a negative impact on the overall growth of plants. This may be because the formation of root sheaths requires plants to consume additional energy and resources, thereby slowing down the progress of other growth activities. This reduction in biomass may affect the yield and overall drought resistance of rice (Figure 1). Figure 1 Drought induces the formation of rhizosheaths in rice but decreases plant biomass (Adopted from Lei et al., 2023) Image caption: a: Daily SWC under different irrigation treatments; b: Total root length; c: Total rhizosheath weight; d: Dry shoot weight; e: Dry root weight of rice after irrigation treatments for 24 days; a~e: Data are the means±SE, bars with different letters were significantly different at P<0.05; WW: Well-watered; DT1: drought treatment I; DT2: drought treatment II (Adopted from Lei et al.,
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