Paclobutrazol Enhanced Stem Lodging Resistance of Direct-Seeded Rice by Affecting Basal Internode Development
Author:
Liu Weiyang1, Cui Jiehao1, Ran Cheng12, Zhang Yuchen1, Liang Jianuo1, Shao Xiwen13, Zhang Qiang1, Geng Yanqiu13ORCID, Guo Liying13
Affiliation:
1. Agronomy College, Jilin Provincial Laboratory of Crop Germplasm Resources Jilin Agricultural University, Changchun 130118, China 2. Heyuan Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Heyuan 517000, China 3. National Crop Variety Approval and Characterization Station, Jilin Agricultural University, Changchun 130118, China
Abstract
The objectives of this study were to explore the mechanism of stem mechanical strength in direct-seeded rice (DSR) as affected by paclobutrazol, especially its related endogenous hormone and cell wall component changes in culm tissue and response to the application of paclobutrazol. Field experiments were conducted in Changchun County, Jilin Province, China, by using two japonica rice varieties, Jiyujing and Jijing305, with soaking seeds in paclobutrazol at concentrations of (0 mg L−1, S0; 50 mg L−1; S1; 100 mg L−1; S2; 150 mg L−1, S3; 200 mg L−1, S4) in 2021 and 2022. The results suggest that the application of paclobutrazol increased the grain yield and reduced the lodging rate of DSR. Compared with the S0 treatments, soaking the seeds in paclobutrazol treatments rapidly shortened the length of the basal internode by decreasing the endogenous indole acetic acid (IAA) and gibberellin A3 (GA3) contents in culm tissue. The larger breaking strength (M) was attributed to a higher section modulus (SM) and bending stress (BS). The higher mechanical tissue thickness in culm tissue under paclobutrazol treatments, which was raised by higher endogenous zeatin and zeatin riboside (Z+ZR) content in culm tissue, increased the culm diameter, culm wall thickness, and section modulus (SM) of the internode. Compared with the S0 treatments, soaking the seeds in paclobutrazol treatments increased the cellulose content, lignin content, activities of lignin-related enzymes, and expression of key genes in lignin biosynthesis, as well as resulted in a higher bending stress (BS) to enhance the culm breaking strength (M).
Funder
National Key R&D Program of China Jilin Provincial Department of Science and Technology
Reference64 articles.
1. Relationship between characteristics of basal internodes and lodging and its physiological mechanism in direct-seeded rice;Liu;J. Agron. Crop Sci.,2023 2. Kobayashi, K., Wang, X., and Wang, W. (2023). Genetically Modified Rice Is Associated with Hunger, Health, and Climate Resilience. Foods, 14. 3. Liang, C., Li, Y., Zhang, K., Wu, Z., Liu, J., Liu, J., Zhou, C., Wang, S., Li, F., and Sui, G. (2023). Selection and Yield Formation Characteristics of Dry Direct Seeding Rice in Northeast China. Plants, 12. 4. Rice direct seeding: Experiences, challenges and opportunities;Farooq;Soil Till. Res.,2011 5. Dry direct-seeded rice as an alternative to transplanted-flooded rice in Central China;Liu;Agron. Sustain. Dev.,2015
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