Next Article in Journal
Smoke Compounds Compensate for Light Irrespective of Its Spectrum in Positively Photoblastic German Chamomile Seeds, Although Red Light Is Crucial
Previous Article in Journal
Mechanisms and Management Strategies for Satsuma Mandarin Fruit Cracking
Previous Article in Special Issue
Development of a Drought Monitoring System for Winter Wheat in the Huang-Huai-Hai Region, China, Utilizing a Machine Learning–Physical Process Hybrid Model
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Agronomy
Volume 15
Issue 3
10.3390/agronomy15030699
agronomy-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Lodging Resistance of Japonica Hybrid Rice Plants Studied in Relation to Mechanical and Physicochemical Characteristics

by
Liying Zhang
1,
Zuobin Ma
1,
Na He
1,
Zhiqiang Tang
1,
Changhua Wang
1,
Wenjing Zheng
1,
Hui Wang
2,
Guomin Sui
2,
Hong Gao
1 and
Lili Wang
1,*
1
Rice Research Institute of Liaoning Province, Shenyang 110101, China
2
Liaoning Academy of Agricultural Sciences, Shenyang 110101, China
*
Author to whom correspondence should be addressed.
Agronomy 2025, 15(3), 699; https://doi.org/10.3390/agronomy15030699
Submission received: 11 February 2025 / Revised: 10 March 2025 / Accepted: 12 March 2025 / Published: 13 March 2025
(This article belongs to the Special Issue Crop Production in the Era of Climate Change)
Browse Figures
Versions Notes

Abstract

:
The research on rice lodging resistance holds immeasurable value for achieving high yield, stable production, and superior quality of rice. To investigate the effects of mechanical properties and physicochemical characteristics of Japonica hybrid rice on its lodging resistance ability under natural field cultivation conditions, LY1052, LY9906, and GY1, which were mainly popularized in northern China, were selected as the experimental subjects, and NL313, Japonica hybrid rice prone to lodging, was taken as the control (NL313).The max bending force, breaking moment, bending section coefficient, single stem weight mass moment, bending strength, Young’s elastic modulus, inertia moment, and other mechanical indexes were measured by the bending test and tensile test, and the correlations between mechanical indexes, physicochemical indexes, and lodging index were studied. There was an extremely significant difference in the lodging index of experimental subjects and control (NL313) (p < 0.05). Therefore, it was concluded that the lower plant height and lighter panicle were not the stronger lodging resistance under appropriate cultivation conditions. Optimization of rice plant-type structure can achieve the unity of high culm and high yield. The lodging resistance of rice could be improved by shortening the internode length, increasing the tissue thickness and vascular bundle area, and increasing the content of cellulose and potassium in the stem. It was also found that the lodging resistance of rice plants was positively correlated with the maximum stem bending force, breaking moment, bending section coefficient, bending strength, and Young’s elastic modulus (p < 0.01) and negatively correlated with single stem weight mass moment and inertia moment (p < 0.01). It is feasible to select them as reference indexes of the lodging resistance of rice. The experimental results not only help to enrich the theoretical system of rice lodging resistance research but also provide an essential reference and basis for formulating scientific cultivation and management measures and breeding lodging-resistant rice varieties in practical production, which is of great significance for ensuring global food security and promoting sustainable agricultural development.

1. Introduction

Rice is one of the most important food crops in the world, and its stability and high yield are of great significance for ensuring global food security [1,2,3]. However, a major challenge in rice production is lodging [4]. Lodging not only directly leads to a significant decline in rice yield but may also lead to deterioration in rice quality, increase the difficulty and cost of harvesting, and even lead to panicle germination and fungal diseases, which further affect the commodity value of rice [5,6]. In particular, under high-yield cultivation conditions, both the biomass and the lodging risk of rice plants increased [7]. Therefore, studying the lodging resistance of rice and exploring its mechanical and physicochemical characteristics are of inestimable value for achieving stable high yield and quality in rice [8,9]. This is not only related to the economic benefits of agricultural production but also key to ensuring national food security and promoting sustainable agricultural development [10,11,12].
Scholars at home and abroad have conducted extensive and in-depth research on the lodging resistance of rice, including variety selection [13,14], cultivation management [15,16,17] and environmental factors [18,19]. The results show that the lodging resistance of rice was the result of genetic characteristics [20,21,22], cultivation management measures [23,24] and climatic conditions [25,26]. In terms of the genetic characteristics of different varieties, the lodging resistance of rice was closely related to plant height, stem thickness, internode length, stem wall thickness, number of vascular bundles, and stem chemical composition [27,28]. The lodging resistance of rice can be effectively enhanced by shortening the internode length of the stem base and increasing the content of cellulose, soluble sugar, potassium, and silicon in the stem [29]. In addition, lignin, a critical component of the secondary cell wall, significantly enhances stem rigidity and compressive strength by cross-linking with cellulose and hemicellulose. Higher lignin content in rice stems improves mechanical resistance to bending and shearing forces, thereby reducing lodging risk under adverse environmental conditions [30]. In terms of cultivation management, reasonable fertilizer application, planting density, and the use of plant growth regulators can significantly affect the lodging resistance of rice [31,32]. In addition, climatic conditions such as strong wind and heavy rain are important factors affecting rice lodging [33].
Although remarkable progress has been made in research on lodging resistance in rice at home and abroad, there are still some shortcomings [34]. First of all, systematic comparison of the mechanical and physicochemical characteristics of different lodging-resistant rice varieties is not sufficient, especially in Japonica hybrid rice varieties, and further research is needed in this field [35]. Secondly, although the existing lodging resistance evaluation systems are diverse, further improvement is needed in evaluation methods that combine a theoretical basis and practicability [36]. Thirdly, the specific influencing mechanism of different cultivation environments and management measures on lodging resistance is not completely clear, especially under complex and changeable field conditions; the formulation of targeted comprehensive anti-lodging countermeasures still needs to be further explored [37,38].
Recent studies have focused on genetic traits, cultivation practices, and environmental factors influencing lodging resistance. However, systematic comparisons of mechanical and physicochemical properties in hybrid Japonica rice remain limited. Furthermore, existing evaluation systems lack practical applicability under field conditions. This study addresses these gaps by: (1) Quantifying mechanical (e.g., bending strength) and physicochemical (e.g., cellulose content) traits across lodging-resistant and susceptible varieties. (2) Analyzing correlations between these traits and lodging resistance. (3) Proposing integrated strategies for improving lodging resistance through breeding and cultivation.

2. Materials and Methods

2.1. Plant Material and Growth Conditions

Liaoyou 1052 (LY1052), Liaoyou 9906 (LY9906), and Gangyou 1 (GY1) are Japonica hybrid rice varieties characterized by semi-erect plant architecture and compact panicles, developed through traditional hybrid breeding techniques in recent years. Compared to earlier Japonica hybrids (notably curved-panicle types), these varieties demonstrate markedly superior lodging resistance. Their compact plant structure, combined with erect leaves, reduces wind resistance, enhancing stability under adverse weather conditions such as strong winds and heavy rain. Additionally, these cultivars exhibit vigorous tillering capacity and well-developed root systems, which improve nutrient and water uptake from the soil, thereby bolstering overall stress tolerance. Crucially, their robust stems exhibit exceptional mechanical strength, enabling them to withstand greater external forces and significantly reducing the risk of stem breakage or lodging. These attributes position these varieties as ideal models for investigating lodging resistance mechanisms. In-depth research into these traits will provide critical theoretical insights and practical frameworks for breeding future generations of lodging-resistant rice varieties (Figure 1).

2.2. Experimental Design and Process

The experiment was conducted from April 2022 to October 2023 at the experimental base of Liaoning Rice Research Institute (123°19′ E, 41°38′ N, altitude: 49 m). The temperature data throughout the rice-growing season are presented in Figure 2. The total rainfall was 937.0 mm in 2022 and 651.7 mm in 2023. The experimental field was a multi-year continuous cropping paddy field with yellow clay loam soil, medium fertility, strong water retention, well water irrigation, and convenient drainage and irrigation. The soil properties were as follows: pH 7.17; total nitrogen, 14.38 g kg−1; total phosphorus, 0.77 g kg−1; total potassium, 21.08 g kg−1; alkalined nitrogen, 156.1 mg kg−1; available phosphorus, 25.01 mg kg−1; available potassium, 226.9 mg kg−1; and organic matter, 19.55 g kg−1. A random block design was adopted with 3 repetitions. The seeds were sown on 15 April, and the seedlings were kept dry on the nutritious soil. The seedlings were transplanted on 20 May. The plot area was 15 m2, and the distance between rows and plants was 30 cm × 13.3 cm. Amounts of 900 kg ammonium sulfate, 150 kg diammonium phosphate, and 120 kg potassium sulfate were applied to each hectare of the experimental field. The ratio of nitrogen application was 4:4:2; that is, base fertilizer accounted for 40% of the total nitrogen application, green tillering fertilizer accounted for 40% (green fertilizer accounted for 15% and tillering fertilizer accounted for 25%), and panicle fertilizer accounted for 20%. Other fields were managed in the same way as the production field. The tillering number of 30 random plants was investigated before sampling, and the average tillering number was taken as the tillering number of 10 sampling plants in each district.

2.3. Experimental Items and Methods

(1)
Panicle features: At 21 days after full heading, 10 representative plants were selected from each plot as samples. The inner and outer cut angles of the panicles were measured using a protractor, and the numbers, length, extension length, and fresh weight of the panicles were measured at the same time.
(2)
Plant type features: A total of 10 plants with the same growth in each plot were selected, and the main stem was selected. The length, width, base angle (the angle between the leaf base and the stem), and leaf open angle (the angle between the straight line between the tip and the leaf pillow and the stem) were measured.
(3)
Stem morphological features: A total of 10 representative plants from each plot were taken as samples, and the plant height, gravity center height, internode numbers, internode length, internode fresh weight, leaf sheath length, leaf sheath fresh weight, leaf length, leaf fresh weight, and the corresponding dry weight were measured using a ruler and a scale.
(4)
Cell and vascular structure: Generally, the first internode of the rice stem is shorter, and lodging often occurs in the second segment. Therefore, the second internode of the stem was studied in more detail in this experiment. Fresh sections of the second internode were prepared, observed, and imaged under an Olympus IX81 fluorescent inverted microscope. The cross-sectional area, number of cell layers, and number and area of vascular bundles were measured through Image-Pro Plus software.
(5)
Chemical composition: The 30 cm stem on the ground was deoxidized at 105 °C for 30 min, dried at 80 °C to a constant mass, crushed, and sifted through a grinder so that the particle diameter was less than 0.254 mm, and then the contents of cellulose, lignin, silicon, and potassium were measured. The silicon and potassium contents were determined through inductively coupled plasma mass spectrometry. A polyester net bag method (DB37T3370-2018 [39]) was adopted to determine the content of cellulose and lignin.
(6)
Mechanical properties: The bending test for the stems was carried out on a universal material test machine (JVJ-2DS, Shanghai Jujing Precision Instrument Manufacturing Co., Ltd., Shanghai, China.) based on the three-point bending principle. The max bending force, breaking moment, bending section coefficient, single stem weight mass moment, bending strength, Young’s elastic modulus, inertia moment, and other mechanical properties of the rice stems were measured, and then the lodging index of the rice stems was calculated. The displacement speed of the sensor was 5 mm/min. Stem yield failure occurs at the point where the pressure reaches the maximum value, that is, the maximum bending resistance of the stem Fmax (N). Before the experiment, basic parameters such as the outer and inner diameter of the stem’s hollow section were measured and calculated with a Vernier caliper. Equations (1)–(7) were adapted from Seko et al. (1959) [40,41] to calculate mechanical properties.
Breaking moment (BM): In Formula (1), Fmax (N) is the maximum bending resistance of the internode; L is the distance between the fulcrum at both ends (cm); and g is the acceleration of gravity (N/kg).
BM = 103FmaxL/4g
Bending section coefficient (BSC): In Formula (2), a1 is the outer diameter and the short axis length of the hollow section (mm); b1 is the outer diameter and the long axis length of the hollow section (mm); a2 is the inner diameter and the short axis length of the hollow section (mm); and b2 is the inner diameter and the long axis length of the hollow section (mm).
BSC = π ( α 1 3 b 1 − α 2 3 b 2 ) / 32 a 1
Inertia moment (LM 3): In Formula (3), a is the semi-major axis length of the outer diameter of the elliptic hollow section, mm; b is the semi-minor axis length of the outer diameter of the oval hollow section, mm; and t is the mean wall thickness of the stem, mm.
LM = π [ab3 − (a − t) (b − t)3]/4
Young’s elastic modulus (YEM): In Formula (4), δ is the deflection value of the center of the stem, mm.
YEM = FmaxL/48δLM
Single stem weight mass moment (SMM): In Formula (5), BL is the distance from the broken part of the stem internode to the top of the stem (cm); FW is the fresh mass from the broken part of the stem internode to the top of the stem (g).
SMM = BL·FW
Bending stress (BS): In Formula (6), BM is the internode fracture bending moment (g·cm); BSC is the bending section coefficient (mm3).
BS = 10BM/BSC
Lodging index (LI): In Formula (7), SMM is the single stem weight mass moment (g·cm); BM is the breaking moment (g·cm).
LI = SMM/BM

2.4. Statistical Analysis of Data

Data were analyzed using SPSS 25.0. One-way ANOVA with Tukey’s HSD post hoc test (α = 0.05) compared means across varieties. Pearson correlation coefficients (r) assessed relationships between lodging index and physicochemical and mechanical traits. The data for the two years were consistent with no significant difference. Therefore, the data were summarized for statistical analysis.

3. Results

3.1. Panicle Characteristics

There were significant differences in panicle numbers, inner cut angle, outer cut angle, and single panicle fresh height (p < 0.05); however, there were no significant differences in panicle length and panicle extension length between the experimental subjects (LY1052, LY9906, and GY1) and control (NL313) (Figure 3). The panicle numbers of LY1052, LY9906, and GY1 decreased by 17.13%, 32.60%, and 27.62%; the inner cut angle decreased by 43.68%, 47.78%, and 36.09%; the outer cut angle decreased by 38.97%, 48.33%, and 36.10%; and the single panicle fresh weight increased by 83.28%, 86.87%, and 150.75%, compared with the control (NL313), respectively.

3.2. Plant Type Characteristics

There were significant differences in plant height, flag leaf base angle, flag leaf open angle, penultimate leaf open angle, and penultimate leaf base angle (p < 0.05); and no significant differences in the base and open angle of the antepenultimate leaf between experimental subjects (LY1052, LY9906, and GY1) and control (NL313) (Figure 4). The plant height of LY1052, LY9906, and GY1 increased by 9.19%, 9.66%, and 12.22%; the flag leaf base angle decreased by 73.21%, 59.66%, and 42.45%; the flag leaf open angle decreased by 69.61%, 54.47%, and 35.40%; the penultimate leaf open angle decreased by 35.42%, 23.43%, and 39.36%; and the penultimate leaf base angle increased by 9.53%, 30.16% and 3.14% compared with control (NL313), respectively.

3.3. Stem Morphological Characteristics

There were significant differences in gravity, second and third internode length, second and third sheath length, and third sheath weight (p < 0.05), and no significant differences in second and third internode weight and second sheath weight between experimental subjects (LY1052, LY9906, and GY1) and control (NL313) (Table 1). The gravity center height of LY1052, LY9906, and GY1 decreased by 10.84%, 6.58%, and 6.11%; the second internode length decreased by 7.14%, 16.20%, and 16.42%; the third sheath length decreased by 5.41%, 21.32%, and 14.12%; the second sheath length decreased by 4.50%, 9.90%, and 9.13%; the third sheath length decreased by 11.09%, 12.54%, and 19.15%; and the third sheath weight increased by 250.77%, 32.82%, and 209.65% compared with the control (NL313), respectively.

3.4. Cell and Vascular Structure

The cell structure, vascular bundle number, and size of the stem of the second internode were observed and measured under a microscope (Figure 5). There were significant differences in tissue layer number, tissue thickness, cell thickness, large and small vascular number, and large and small vascular area (p < 0.05), and no significant differences in cell layer number and cross area between experimental subjects (LY1052, LY9906, and GY1) and control (NL313) (Table 2). The tissue layer number of LY1052, LY9906, and GY1 increased by 8.90%, 19.90%, and 25.65%; the tissue thickness increased by 15.91%, 19.23%, and 23.23%; the cell thickness increased by 36.18%, 56.93%, and 61.60%; the large vascular number increased by 3.79%, 9.66%, and 7.93%; the small vascular number increased by 15.81%, 20.16%, and 24.11%; the large vascular area increased by 31.21%, 59.46%, and 87.44%; and the small vascular area increased by 55.50%, 60.21%, and 90.18% compared with control (NL313), respectively.

3.5. Chemical Composition

There were significant differences in the cellulose and potassium content of the stem (p < 0.05), and no significant differences in the lignin and silicon content of the stem or the cellulose, lignin, silicon, and potassium content of the sheath between experimental subjects (LY1052, LY9906, and GY1) and control (NL313) (Table 3). The cellulose content of the stem of LY1052, LY9906, and GY1 increased by 36.28%, 54.36%, and 51.89% and the potassium content of the stem increased by 77.08%, 144.61%, and 214.75% compared with the control (NL313), respectively.

3.6. Mechanical Properties

There were significant differences in max bending resistance, breaking moment, bending section coefficient, single stem weight mass moment, bending strength, Young’s elastic modules, inertia moment, and lodging index (p < 0.05) between experimental subjects (LY1052, LY9906, and GY1) and control (NL313) (Table 4). The max bending resistance of LY1052, LY9906, and GY1 increased by 59.06%, 67.66%, and 83.59%; the breaking moment increased by 21.11%, 29.03%, and 34.61%; the bending section coefficient increased by 17.25%, 19.61%, and 21.87%; the single stem weight mass moment decreased by 43.04%, 45.21%, and 48.12%; the bending strength increased by 17.67%, 23.05%, and 25.88%; Young’s elastic modules increased by 27.84%, 35.23%, and 47.21%; the inertia moment decreased by 6.88%, 8.85%, and 9.61%; and the lodging index decreased by 52.94%, 57.52%, and 61.44% compared with the control (NL313), respectively.

3.7. Correlation Between Lodging Characteristics and Lodging Index

There were significant positive correlations between the inner cut angle, outer cut angle, inertia moment, and lodging index (p < 0.05), and an extremely significant positive correlation between single stem weight mass moment and lodging index (p < 0.01). There were significant negative correlations between the cellulose content of the stem, plant height, tissue thickness, cell thickness, large and small vascular number, max bending resistance, breaking moment, bending section coefficient, bending strength, Young’s elastic modulus, and lodging index (p < 0.05) (Table 5).

4. Discussion

4.1. Effects of Stem Physicochemical Characteristics on Lodging Resistance of Japonica Hybrid Rice

Lodging is caused by an imbalance of the mechanical properties of the base stem and the load on the upper stem and is defined as the failure of the support function of the stem [42]. The lodging indexes of experimental subjects in this study were significantly lower than those of control (NL313), indicating that their lodging resistance was significantly higher than that of control (NL313). There were significant differences between experimental subjects and control (NL313) in terms of panicle characteristics, plant type characteristics, stem morphological characteristics, cell and tissue structure, stem chemical composition, etc.
Rice yield is determined by the effective panicle numbers per unit area, the number of grains per panicle, and the quality of each grain [43], and is closely related to panicle characteristics such as the inner and outer cut angle [44]. The panicle numbers, inner cut angle, and outer cut angle of the experimental subjects were significantly lower than those of control (NL313). Although the single panicle fresh weight of control (NL313) was significantly lower than that of the experimental subjects, the panicle distribution was relatively dense, indicating that the panicle characteristics of control (NL313), such as high panicle numbers, large inner and outer cut angles, and dense panicle distribution, might make the rice panicle more open and increase the wind bearing area. These factors make control (NL313) more prone to lodging in the face of strong winds or bad weather. The significant differences between experimental subjects and control (NL313) in terms of panicle numbers, inner and outer cut angles, and single panicle fresh weight may reflect the genetic characteristics, growth habits, and adaptation strategies of different varieties.
In order to achieve further breakthroughs in rice yield, biological yield should be increased first to increase yield per unit area [45]. The most effective way to increase biological yield is to appropriately increase plant height, which is restricted by leaf photosynthesis, light, water, the transport of other nutrients, and other factors [46]; the plant type characteristics of rice plants have a great impact on these indicators [47]. The plant height of control (NL313) is significantly lower than that of experimental subjects, which usually means that it may have better lodging resistance because shorter plants are generally more stable. However, in practice, lodging resistance is also affected by other factors; the base angle and open angle of the flag leaf and the open angle of the penultimate leaf of control (NL313) were significantly larger than those of the experimental subjects. Although the base angle of the penultimate leaf was significantly lower than that of the experimental subjects, the ratio of the base angle to the open angle was small, indicating that the flag leaf and penultimate leaf were more flat, which may increase the area affected by wind and the spatial arrangement between the leaves and the position of the plant’s center of gravity, thus affecting its stability.
The stem is one of the main parts of the rice plant, and its growth and development have a crucial effect on the yield and quality of the rice [48]. First of all, by supporting the leaves, it provides the necessary support for the rice panicles. At the same time, it also plays the role of transporting water and nutrients [49]. In the growing process of rice, the morphological characteristics of the stem, such as internode length and weight and leaf sheath length and weight, have very important effects on plant height and tillering [50]. The second and third segments of control (NL313) were significantly longer than those of the experimental subjects, meaning that the stem of control (NL313) was more elongated in these parts. The length of the second and third sheaths of control (NL313) was significantly higher than that of the experimental subjects, which indicated that the sheaths were relatively thin. The third sheath weight of control (NL313) was significantly higher than that of the experimental subjects, which increased the height of its center of gravity and reduced its stability to a certain extent. In addition, the slender stems and thin sheaths of control (NL313) may reduce the mechanical strength and supporting ability of the stems. In strong winds or bad weather conditions, elongated stems are more susceptible to bending or breaking under external forces, which causes an increased probability of lodging [51].
By dissecting the stem, it can be seen that the surface of the rice internode is raised and there is a full interior [52]. From the outside to the inside are the epidermis, basic tissue, vascular bundle, and pulp cavity (hollow part) [53]. The basic tissues are inside the epidermis and between the vascular bundles [54]. The parenchyma cells, which constitute the basic tissues of rice, disintegrate to form the pulp cavity, while the sachyparietal cells form the strong mechanical tissues [55]. The number of tissue layers of stem cells in control (NL313) was significantly lower than that in the experimental subjects, and the tissue thickness was also the thinnest, indicating that the stem structure of control (NL313) was relatively weak. In addition, the thickness of control (NL313) cells was significantly lower than that of the experimental subjects, indicating that their cell structure was relatively less dense and thinner, meaning that the cell structure of the stem is relatively weak and may be more susceptible to external influences and deformation or damage. The number of large and small vascular bundles in control (NL313) was significantly lower than that in the experimental subjects. Vascular bundles are the tissues that transport water and nutrients in plants, and a lower number may affect nutrient transport and the support ability of stems. In addition, the area of large and small vascular bundles in control (NL313) was significantly lower than that in the experimental subjects, indicating that not only was the number of vascular bundles small, but also the size of each vascular bundle was relatively small, which may have greatly reduced the mechanical strength and supporting capacity of the stem. The differences between control (NL313) and the experimental subjects in these aspects may directly result in their lower lodging resistance.
Cellulose, as the main component of the cell wall, is cross-linked by thousands of microfilaments and plays an important role in the mechanical support of the cell wall [56]. The cellulose content of control (NL313) stems was significantly lower than that of the experimental subjects, and the lower cellulose content may directly affect the sturdiness and pressure resistance of the control (NL313) stems, thereby increasing the risk of lodging when confronted with external forces such as wind and rain. Potassium is one of the essential nutrients for plant growth and development and also has a certain influence on the strength and stability of stems [57]. Rice is a food crop that needs more potassium, and sufficient potassium absorption can increase the strength of the rice stem, improve its mechanical properties, reduce the occurrence of diseases and pests, and improve the lodging resistance [58]. The low content of potassium in the control stems may affect their normal physiological function and nutrient transport and then affect their health and stability, resulting in them not being able to maintain the necessary turgor pressure and therefore decreasing the lodging resistance.
There were significant correlations between the lodging index of rice plants and the panicle characteristics, plant type characteristics, stem morphological characteristics, cell and tissue structure, chemical composition, and mechanical properties [59,60]. Therefore, many factors such as genetic characteristics, growth environment, and cultivation management should be taken into consideration during evaluation to understand the formation mechanisms and improvement approaches of lodging resistance in rice plants more comprehensively [61,62].
This study is of great significance for the practical application scenarios of rice variety breeding, cultivation management, lodging resistance monitoring, and comprehensive consideration of lodging resistance and other agronomic traits. In the process of breeding Japonica hybrid rice varieties, the varieties with moderate plant height, reasonable panicle characteristics, stout stems, well-developed vascular bundles, and a high content of cellulose and lignin should be considered. At the same time, mechanical indexes (maximum bending force, elastic modulus, inertia moment, etc.) were used to quantitatively evaluate the lodging resistance ability in order to assist the breeding process. Through reasonable cultivation and management measures (such as reasonable fertilization, irrigation, density control, etc.) to optimize the rice plant type structure, reduce the gravity center height, and improve the stem strength. Especially in terms of potassium supply, it should be ensured that rice plants receive sufficient potassium to improve their lodging resistance. Using the mechanical evaluation indexes adopted in this study, the change in the lodging resistance of rice plants was monitored in relation to field management, lodging risk was identified, and corresponding measures were taken for prevention and control. In variety selection and cultivation management, it is necessary to consider the relationship between lodging resistance and other agronomic traits, such as yield and quality, and find the best balance point to achieve the unity of high yield, high quality, and lodging resistance.
Our findings align with Liu et al. (2022) [38], who reported that cellulose content and vascular bundle density are critical for stem strength. However, unlike Guo et al. (2020) [47], who emphasized plant height reduction, we demonstrate that optimized internode length and potassium fertilization can reconcile high culm height with lodging resistance.

4.2. Establishment of Mechanical Evaluation Index and Its Effects on Lodging Resistance of Japonica Hybrid Rice

Elastic modulus, bending strength, breaking moment, etc., are widely used in aerospace, petrochemical, mechanical manufacturing, pharmaceutical packaging, paper, metal materials, and mechanical indexes in manufacturing. The application of these mechanical indexes in crop lodging resistance evaluation is still in the early stage of research [35,63,64]. In this study, the maximum stem bending force, breaking moment, bending section coefficient, single stem weight mass moment, bending strength, Young’s elastic modulus, and inertia moment were selected as the evaluation indexes of lodging resistance of Japonica hybrid rice, and the correlations between them and lodging resistance were analyzed. The results show that compared with the experimental subjects, the maximum bending force, breaking moment, bending section coefficient, and bending strength were lower for control (NL313), causing control (NL313) to be more prone to bending or breaking when confronted with external forces such as wind and rain. Young’s modulus (YEM) reflects stem stiffness, where higher YEM (GY1: 8.85 × 104 N/cm2) indicates greater resistance to elastic deformation. Breaking moment (BM) measures the force required to fracture the stem, which correlated strongly with lignin content. The synergy between YEM and BM ensures stems withstand both transient wind forces (via elasticity) and sustained loads (via structural integrity). Conversely, inertia moment (IM) negatively impacted lodging resistance, as higher IM (NL313: 7.2 × 10−3 cm4) increased rotational instability during stem deflection. The low Young’s elastic modulus indicates that control (NL313) has poor recovery ability and is prone to irreversible deformation after loading, which further reduces the lodging resistance. A higher single stem mass moment may increase the risk of bending, while a similar or slightly higher inertia moment does not effectively improve lodging resistance, suggesting that other factors (such as the strength of the stem) have a more significant effect on lodging.

5. Conclusions

In conclusion, lodging-resistant hybrid Japonica rice varieties exhibited shorter basal internodes, thicker cell walls, and higher cellulose/potassium content compared to the susceptible control. Mechanical indices (e.g., bending strength, Young’s modulus) strongly correlated with lodging resistance (p < 0.01), validating their use for screening. These results provide actionable insights for breeding programs and field management to achieve high yield without compromising lodging resistance, contributing to sustainable rice production.

Author Contributions

Conceptualization, L.Z. and H.G.; methodology, L.Z. and Z.M.; software, L.W. and Z.T.; validation, G.S., Z.T. and C.W.; formal analysis, L.W., H.G. and Z.T.; investigation, G.S., L.W. and N.H.; resources, G.S., H.W., C.W. and N.H.; data curation, Z.M. and N.H.; writing—original draft preparation, L.Z., Z.M. and L.W.; writing—review and editing, W.Z., H.W and H.W.; supervision, H.W. and C.W.; project administration, L.W., H.G. and W.Z.; funding acquisition, L.W. and W.Z. All authors have read and agreed to the published version of the manuscript.

Funding

This study was funded by the doctoral Research Start-up Project of the President’s Fund of Liaoning Academy of Agricultural Sciences (2023BS0804), the Major Science and Technology Special Project of Liaoning Province (2024JH1/11700006) and the earmarked fund for China Agriculture Research System (CARS-01).

Data Availability Statement

The data presented in this study are included within the article.

Conflicts of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationship that could be construed as potential conflicts of interest.

References

  1. Huang, M.; Lei, T.; Cao, J.; Tao, Z.; Cao, F.; Chen, J.; Yin, X.; Zou, Y. Linking grain yield and lodging resistance with growth patterns in rice. Exp. Agric. 2022, 58, e24. [Google Scholar] [CrossRef]
  2. Ordonio, R.L.; Matsuoka, M. New path towards a better rice architecture. Cell Res. 2017, 27, 1189–1190. [Google Scholar] [CrossRef]
  3. Pacleb, M.; Jeong, O.Y.; Lee, J.S.; Padolina, T.; Braceros, R.; Pautin, L.; Torollo, G.; Sana, E.E.; Del-Amen, J.Y.; Baek, M.K.; et al. Breeding Temperate Japonica Rice Varieties Adaptable to Tropical Regions: Progress and Prospects. Agronomy 2021, 11, 2253. [Google Scholar] [CrossRef]
  4. Avakyan, E.R.; Dzhamirze, R.R. Rice lodging resistance. RUDN J. Agron. Anim. Ind. 2018, 13, 366–372. [Google Scholar] [CrossRef]
  5. Guha, P.K.; Magar, N.D.; Kommana, M.; Barbadikar, K.M.; Suneel, B.; Gokulan, C.; Lakshmi, D.V.; Patel, H.K.; Sonti, R.V.; Sundaram, R.M.; et al. Strong culm: A crucial trait for developing next-generation climate-resilient rice lines. Physiol. Mol. Biol. Plants 2024, 30, 665–686. [Google Scholar] [CrossRef] [PubMed]
  6. Gu, H.; Xiao, Z.; Meng, Q.; Fa, X.; Wang, C.; Jing, W.; Wang, W.; Zhu, K.; Zhang, W.; Gu, J.; et al. The synergistic effect of variety improvement and alternate wetting and drying irrigation on yield, water use efficiency and lodging resistance in rice. Eur. J. Agronomy 2025, 164, 127507. [Google Scholar] [CrossRef]
  7. Shah, L.; Yahya, M.; Shah, S.M.A.; Nadeem, M.; Ali, A.; Ali, A.; Wang, J.; Riaz, M.W.; Rehman, S.; Wu, W.; et al. ImprovingLodging Resistance: Using Wheat and Rice as Classical Examples. Int. J. Mol. Sci. 2019, 20, 4211. [Google Scholar] [CrossRef]
  8. Venkata, R.P.R.; Lakshminarayana, R.V.; Akkareddy, S.; Hariprasad, R.K.; Siddiq, E.A. Genetic analysis of culm strength and its related traits in rice (Oryza sativa L.). Appl. Biol. Res. 2019, 21, 166–175. [Google Scholar]
  9. Mohidem, N.A.; Hashim, N.; Shamsudin, R.; Che Man, H. Rice for food security: Revisiting its production, diversity, rice milling process and nutrient content. Agriculture 2022, 12, 741. [Google Scholar] [CrossRef]
  10. Ko, H.; Reynante, L.O.; Makoto, M. Engineering the lodging resistance mechanism of post-Green Revolution rice to meet future demands. Proc. Jpn. Acad. 2017, 93, 220–233. [Google Scholar]
  11. Bian, J.; Ren, G.; Han, C.; Xu, F.; Qiu, S.; Tang, J.; Zhang, H.; Wei, H.; Gao, H. Comparative analysis on grain quality and yield of different panicle weight indica-Japonica hybrid rice (Oryza sativa L.) cultivars. J. Integr. Agric. 2020, 19, 999–1009. [Google Scholar] [CrossRef]
  12. Bian, J.; Ren, G.; Xu, F.; Zhang, H.; Wei, H. Comparison of grain yield and quality of different types of Japonica rice cultivars in the northern Jiangsu plain. J. Integr. Agric. 2021, 20, 2065–2076. [Google Scholar] [CrossRef]
  13. Ichiro, N.; Hideki, S.; Kei, M.; Hideo, M.; Shuichi, F.; Utako, Y. Genetic studies for breeding of rice cultivars with superior grain appearance and lodging resistance from the rice cultivar ‘Emi-no-kizuna’. Plant Prod. Sci. 2019, 22, 546–553. [Google Scholar]
  14. Ilyushko, M.V.; Romashova, M.V.; Guchenko, S.S. Resistance to Lodging of the Doubled Haploids of the Far East-Bred Rice Oriza sativa L. Russ. Agric. Sci. 2023, 49, 259–264. [Google Scholar] [CrossRef]
  15. Khan, M.I.R.; Trivellini, A.; Chhillar, H.; Chopra, P.; Ferrante, A.; Khan, N.A.; Ismail, A.M. The Significance and Functions of Ethylene in Flooding Stress Tolerance in Plants. Environ. Exp. Bot. 2020, 179, 104188. [Google Scholar] [CrossRef]
  16. Miao, W.; Li, F.; Lu, J.; Wang, D.; Chen, M.; Tang, L.; Xu, Z.; Chen, W. Biochar application enhanced rice biomass production and lodging resistance via promoting co-deposition of silica with hemicellulose and lignin. Sci. Total Environ. 2022, 855, 158818. [Google Scholar] [CrossRef]
  17. Zhou, T.; Cui, R.; Shu, C.; Zhu, K.; Zhang, W.; Zhang, H.; Liu, L.; Wang, Z.; Gu, J.; Yang, J. Combining urea and controlled release nitrogen fertilizer to enhance lodging resistance of rice (Oryza sativa L.) by altering accumulation of silicon and cell wall polymers at high yielding levels. Field Crops Res. 2024, 315, 109459. [Google Scholar] [CrossRef]
  18. Kashiwagi, T. Novel QTL for Lodging Resistance, PRL4, Improves Physical Properties with High Non-Structural Carbohydrate Accumulation of Basal Culms in Rice (Oryza sativa L.). Euphytica 2022, 218, 83. [Google Scholar] [CrossRef]
  19. Shao, Z.; Gu, J.; He, L.; Xu, Y.; Shang, B.; Feng, Z. Effects of elevated ozone, warming, and their interactions on the stem lodging resistance of rice under fully open-field conditions. Agric. Ecosyst. Environ. 2024, 376, 109249. [Google Scholar] [CrossRef]
  20. Mulsanti, I.W.; Yamamoto, T.; Ueda, T.; Samadi, A.F.; Kamahora, E.; Rumanti, I.A.; Thanh, V.C.; Adachi, S.; Suzuki, S.; Kanekatsu, M.; et al. Finding the superior allele of Japonica-type for increasing stem lodging resistance in indica rice varieties using chromosome segment substitution lines. Rice 2018, 11, 25. [Google Scholar] [CrossRef]
  21. Jiang, M.; Yamamoto, E.; Yamamoto, T.; Matsubara, K.; Kato, H.; Adachi, S.; Nomura, T.; Kamahora, E.; Ma, J.; Ookawa, T. Mapping of QTLs associated with lodging resistance in rice (Oryza sativa L.) using the recombinant inbred lines derived from two high yielding cultivars, Tachisugata and Hokuriku 193. Plant Growth Regul. 2019, 87, 267–276. [Google Scholar] [CrossRef]
  22. Mustikarini, E.D.; Prayoga, G.I.; Santi, R.; Nurqirani, Z.; Saragi, H. Genetic Parameter Contributing to Lodging Resistance of F2 Population in Red Rice. IOP Conf. Ser. Earth Environ. Sci. 2019, 334, 012066. [Google Scholar] [CrossRef]
  23. Zhu, H.; Nie, L.; He, X.; Wang, X.; Long, P.; Chen, H. Water and fertilizer management is an important way to synergistically enhance the yeld, rice quality and lodging resistance of hybrid rice. Plants 2024, 13, 2518. [Google Scholar] [CrossRef]
  24. Agake, S.; Ohwaki, Y.; Kojima, K.; Yoshikawa, E.; Artigas, R.M.D.; Bellingrath, K.S.D.; Yamada, T.; Ookawa, T.; Ohkama, O.N.; Yokoyama, T. Biofertilizer with bacillus pumilus TUAT1 spores improves growth, productivity, and lodging resistance in forage rice. Agronomy 2022, 12, 2325. [Google Scholar] [CrossRef]
  25. Zhong, X.; Liang, K.; Peng, B.; Tian, K.; Li, X.; Huang, N.; Liu, Y.; Pan, J. Basal internode elongation of rice as affected by light intensity and leaf area. Crop J. 2020, 8, 62–70. [Google Scholar] [CrossRef]
  26. Zhao, X.; Zhou, N.; Lai, S.; Frei, M.; Wang, Y.; Yang, L. Elevated CO2 improves lodging resistance of rice by changing physicochemical properties of the basal internodes. Sci. Total Environ. 2019, 647, 223–231. [Google Scholar] [CrossRef]
  27. Gui, M.Y.; Wang, D.; Xiao, H.H.; Tu, M.; Li, F.L.; Li, W.C.; Ji, S.D.; Wang, T.X.; Li, J.Y. Studies of the relationship between rice stem composition and lodging resistance. J. Agric. Sci. 2018, 156, 387–395. [Google Scholar] [CrossRef]
  28. Shi, M.; Wang, T.; Sun, D.; Xiong, W.; Kuang, F.; Zhu, D. Distribution law of vascular bundle stiffness in rice stems and microscale simulation. Biosyst. Eng. 2025, 250, 325–342. [Google Scholar] [CrossRef]
  29. Liu, S.; Huang, Y.; Xu, H.; Zhao, M.; Xu, Q.; Li, F. Genetic enhancement of lodging resistance in rice due to the key cell wall polymer lignin, which affects stem characteristics. Breed. Sci. 2018, 68, 508–515. [Google Scholar] [CrossRef]
  30. Liu, Q.; Yin, C.; Li, X.; He, C.; Ding, Z.; Du, X. Lodging resistance of rice plants studied from the perspective of culm mechanical properties, carbon framework, free volume, and chemical composition. Sci. Rep. 2022, 12, 20026. [Google Scholar] [CrossRef]
  31. Tuiwong, P.; Lordkaew, S.; Veeradittakit, J.; Jamjod, S.; Prom-u-thai, C. Efficacy of nitrogen and zinc application at different growth stages on yield, grain zinc, and nitrogen concentration in rice. Agronomy 2022, 12, 2093. [Google Scholar] [CrossRef]
  32. Deng, H.; Li, Y.; Ashraf, U.; Gui, R.; Wang, Z.; Nawaz, H.; Tang, X.; Duan, M.; Mo, Z. The application of liquid fertilizer with reduced nitrogen rate improves the lodging resistance in fragrant rice. J. Soil Sci. Plant Nutr. 2023, 23, 6071–6087. [Google Scholar] [CrossRef]
  33. Weng, F.; Zhang, W.; Wu, X.; Xu, X.; Ding, Y.; Li, G.; Liu, Z.; Wang, S. Impact of low-temperature, overcast and rainy weather during the reproductive growth stage on lodging resistance of rice. Sci. Rep. 2017, 7, 46596. [Google Scholar] [CrossRef]
  34. Durga, P.M.; Kalaimagal, T.; Manonmani, S.; Jagadeesan, R.; Sritharan, N.; Senthilkumar, G. Breeding Resilience: Exploring Lodging Resistance Mechanisms in Rice. Rice Sci. 2024, 31, 659–672. [Google Scholar]
  35. Yang, H.; Huang, J.; Ye, Y.; Xu, Y.; Xiao, Y.; Chen, Z.; Li, X.; Ma, Y.; Lu, T.; Rao, Y. Research Progress on Mechanical Strength of Rice Stalks. Plants 2024, 13, 1726. [Google Scholar] [CrossRef]
  36. Luo, X.; Wu, Z.; Fu, L.; Dan, Z.; Yuan, Z.; Liang, T.; Zhu, R.; Hu, Z.; Wu, X. Evaluation of lodging resistance in rice based on an optimized parameter from lodging index. Crop Sci. 2022, 62, 1318–1332. [Google Scholar] [CrossRef]
  37. Liu, Q.; Ma, J.; Zhao, Q.; Zhou, X. Physical Traits Related to Rice Lodging Resistance under Different Simplified-Cultivation Methods. Agron. J. 2018, 110, 127–132. [Google Scholar] [CrossRef]
  38. Liu, J.; Wang, Z.; Guo, X. Stem characteristic associated with lodging resistance of rice changes with varied alternating drought and flooding stress. Agronomy 2022, 12, 3070. [Google Scholar] [CrossRef]
  39. DB37T3370-2018; National Public Service Platform for Standards Information. SAC: Beijing, China, 2010. Available online: https://std.samr.gov.cn/ (accessed on 22 December 2024).
  40. Seko, H.; Samoto, K.; Suzuki, K. Lodging of rice plant in relation to several different cultural conditions. Jpn. J. Crop Sci. 1959, 27, 173–176. [Google Scholar] [CrossRef]
  41. Zhang, M.H.; Mo, Z.W.; Liao, J.; Pan, S.G.; Chen, X.F.; Zheng, L.; Luo, X.W.; Wang, Z.M. Lodging resistance related to root traits for mechanized wet-seeding of two super rice cultivars. Rice Sci. 2021, 28, 200–208. [Google Scholar]
  42. Tsugawa, S.; Shima, H.; Ishimoto, Y.; Ishikawa, K. Thickness-stiffness trade-off improves lodging resistance in rice. Sci. Rep. 2023, 13, 10828. [Google Scholar] [CrossRef] [PubMed]
  43. Keerthiraj, B.; Biju, S.; Joseph, J.; Job, A.M.; Cockerham, C.C.; Cuo, Y.H.; Zhu, S.G.; Zhang, L.B.; Detang, Z.; Chenghuan, C.; et al. Combining ability studies for lodging resistance and yield traits in rice. Electron. J. Plant Breed. 2021, 12, 1380–1386. [Google Scholar]
  44. Gong, D.; Dai, G.; Chen, Y.; Yu, G. Optimal tillage depths for enhancing rice yield, quality and lodging resistance in the rice production systems of northeast China. PeerJ 2023, 11, e15739. [Google Scholar] [CrossRef]
  45. Rani, M.G.; Satyanarayana, P.V.; Ahmed, M.L.; Rani, Y.A.; Rao, V.S.; Jhansirani, P. Breeding strategies for lodging resistance in rice. Int. J. Bio-Resour. Stress Manag. 2017, 8, 895–903. [Google Scholar] [CrossRef]
  46. Ma, X.; Wu, J.; Su, Y.; Qin, S.; Pilla, F. Utilizing hydrophobic sand to construct an air-permeable aquiclude to enhance rice yield and lodging resistance. Agronomy 2024, 14, 2085. [Google Scholar] [CrossRef]
  47. Guo, Z.; Liu, X.; Zhang, B.; Yuan, X.; Xing, Y.; Liu, H.; Luo, L.; Chen, G.; Xiong, L. Genetic analyses of lodging resistance and yield provide insights into post-Green-Revolution breeding in rice. Plant Biotechnol. J. 2020, 19, 814–829. [Google Scholar] [CrossRef]
  48. Jyothi, B.; Revadi, P.; Chandrappa, A.; Akshay, M.; Subhakara, R.I.; AVSR, S.; Raman, M.S. Genome-wide association studies for a comprehensive understanding of the genetic architecture of culm strength and yield traits in rice. Front. Plant Sci. 2024, 14, 1298083. [Google Scholar]
  49. Shao, Z.; Zhang, Y.; Hu, S.; Gao, B.; Jing, L.; Wang, Y.; Wang, Y.; Yang, L. Impacts of ozone stress on stem lodging characteristics of different indica and Japonica rice cultivars. Crop Sci. 2023, 63, 1508–1524. [Google Scholar] [CrossRef]
  50. Nomura, T.; Ohkubo, S.; Nagano, A.J.; Samadi, A.F.; Adachi, S.; Ookawa, T. Physiological and morphological factors affecting leaf sheath reinforcement and their contribution to lodging resistance in rice. Plant Prod. Sci. 2023, 2, 48–64. [Google Scholar] [CrossRef]
  51. Kato, Y.; Collard, B.C.; Septiningsih, E.M.; Ismail, A.M. Increasing flooding tolerance in rice:combining tolerance of submergence and of stagnant flooding. Ann. Bot. 2019, 124, 1199–1209. [Google Scholar] [CrossRef]
  52. Dang, Z.; Wang, Y.; Wang, M.; Cao, L.; Ruan, N.; Huang, Y.; Li, F.; Xu, Q.; Chen, W. The Fragile culm19 (FC19) mutation largely improves plant lodging resistance, biomass saccharification, and cadmium resistance by remodeling cell walls in rice. J. Hazard. Mater. 2023, 458, 132020. [Google Scholar] [CrossRef] [PubMed]
  53. Liu, W.; Cui, J.; Ran, C.; Zhang, Y.; Liang, J.; Shao, X.; Zhang, Q.; Geng, Y.; Guo, L. Paclobutrazol enhanced stem lodging resistance of direct-seeded rice by affecting basal internode development. Plants 2024, 13, 2289. [Google Scholar] [CrossRef] [PubMed]
  54. Zhang, W.; Wu, L.; Wu, X.; Ding, Y.; Li, G.; Li, J.; Weng, F.; Liu, Z.; Tang, S.; Ding, C.; et al. lodging resistance of Japonica rice (Oryza Sativa L.): Morphological and anatomical traits due to top-dressing nitrogen application rates. Rice 2016, 9, 35. [Google Scholar] [CrossRef] [PubMed]
  55. Lu, Y.; Cui, J.; Bao, S.; Liu, W.; Geng, Y.; Liang, X.; Li, S.; Guo, L.; Shao, X. Effects of nitrogen fertilizer application rate on lodging resistance for rice (Oryza sativa L.) stem. Sci. Rep. 2025, 15, 2149. [Google Scholar] [CrossRef]
  56. Wang, Y.; Wang, M.; Yan, X.; Chen, K.; Tian, F.; Yang, X.; Cao, L.; Ruan, N.; Dang, Z.; Yin, X.; et al. The DEP1 Mutation Improves Stem Lodging Resistance and Biomass Saccharification by Affecting Cell Wall Biosynthesis in Rice. Rice 2024, 17, 35. [Google Scholar] [CrossRef]
  57. Zhang, S.; Yang, Y.; Zhai, W.; Tong, Z.; Shen, T.; Li, Y.; Zhang, M.; Sigua, G.C.; Chen, J.; Ding, F. Controlled-Release Nitrogen Fertilizer Improved Lodging Resistance and Potassium and Silicon Uptake of Direct-Seeded Rice. Crop Sci. 2019, 59, 2733–2740. [Google Scholar] [CrossRef]
  58. Olagunju, S.O.; Atayese, M.O.; Sakariyawo, O.S.; Dare, E.O. Effects of multi-growth stage water deficit and orthosilicic acid fertiliser on lodging resistance of rice cultivars. Crop Pasture Sci. 2022, 73, 370–389. [Google Scholar] [CrossRef]
  59. Gong, D.; Xu, Z.; Zheng, W.; Dai, G.; Chen, Y.; Yu, G. Biochar application improves the yield, lodging resistance, and lignin synthesis mechanism in rice. Crop Sci. 2024, 64, 968–981. [Google Scholar] [CrossRef]
  60. Wang, X.; Xu, L.; Li, X.; Yang, G.; Wang, F.; Peng, S. Grain yield and lodging-related traits of ultrashort-duration varieties for direct-seeded and double-season rice in Central China. J. Integr. Agric. 2022, 21, 2888–2899. [Google Scholar] [CrossRef]
  61. Ding, C.; Luo, X.; Wu, Q.; Lu, B.; Ding, Y.; Song, J.; Li, G. Compact plant type rice has higher lodging and N resistance under machine transplanting. J. Integr. Agric. 2021, 20, 65–77. [Google Scholar] [CrossRef]
  62. Ahmad, F.S.; Hiroki, S.; Tadamasa, U.; Toshio, Y.; Shunsuke, A.; Taiichiro, O. Identification of quantitative trait loci for breaking and bending types lodging resistance in rice, using recombinant inbred lines derived from Koshihikari and a strong culm variety, Leaf Star. Plant Growth Regul. 2019, 89, 83–98. [Google Scholar]
  63. Yuan, S.; Linquist, B.A.; Wilson, L.T.; Cassman, K.G.; Stuart, A.M.; Pede, V.; Miro, B.; Saito, K.; Agustiani, N.; Aristya, V.E.; et al. Sustainable intensification for a larger global rice bowl. Nat. Commun. 2021, 12, 7163. [Google Scholar] [CrossRef] [PubMed]
  64. Ke, S.; Luan, X.; Liang, J.; Hung, Y.; Hsieh, T.; Zhang, X. Rice OsPEX1, an extensin-like protein, affects lignin biosynthesis and plant growth. Plant Mol. Biol. 2019, 100, 151–161. [Google Scholar] [CrossRef] [PubMed]
Agronomy 15 00699 g001
Figure 1. Plant material. The Japonica hybrid rice varieties LY1052, LY9906, and GY1, which are widely used in northern China, were selected as the experimental varieties. The easy topsy Japonica rice variety NL313, was selected as the control variety, which were provided by Liaoning Rice Research Institute.
Figure 1. Plant material. The Japonica hybrid rice varieties LY1052, LY9906, and GY1, which are widely used in northern China, were selected as the experimental varieties. The easy topsy Japonica rice variety NL313, was selected as the control variety, which were provided by Liaoning Rice Research Institute.
Agronomy 15 00699 g001
Agronomy 15 00699 g002
Figure 2. Comparison of average daily temperature curves from April to October in 2022 and 2023. This figure displays the temperature data at the experimental station of Liaoning Rice Research Institute.
Figure 2. Comparison of average daily temperature curves from April to October in 2022 and 2023. This figure displays the temperature data at the experimental station of Liaoning Rice Research Institute.
Agronomy 15 00699 g002
Agronomy 15 00699 g003
Figure 3. Panicle features of different Japonica rice varieties. The deviation in graphs on the figure represents standard error of mean. The means with different small alphabetical letters show the significant differences among the panicle features of different Japonica rice varieties according to the least significant difference test at the 95% level of confidence, while “ns” indicates non-significant difference.
Figure 3. Panicle features of different Japonica rice varieties. The deviation in graphs on the figure represents standard error of mean. The means with different small alphabetical letters show the significant differences among the panicle features of different Japonica rice varieties according to the least significant difference test at the 95% level of confidence, while “ns” indicates non-significant difference.
Agronomy 15 00699 g003
Agronomy 15 00699 g004
Figure 4. Plant type characteristics of different Japonica rice varieties. The deviation in graphs on the figure represents standard error of mean. The means with different small alphabetical letters show the significant differences among the plant type characteristics of different Japonica rice varieties according to the least significant difference test at the 95% level of confidence, while “ns” indicates non-significant difference. The plant height is half of its original value.
Figure 4. Plant type characteristics of different Japonica rice varieties. The deviation in graphs on the figure represents standard error of mean. The means with different small alphabetical letters show the significant differences among the plant type characteristics of different Japonica rice varieties according to the least significant difference test at the 95% level of confidence, while “ns” indicates non-significant difference. The plant height is half of its original value.
Agronomy 15 00699 g004
Agronomy 15 00699 g005
Figure 5. Cell and vascular structure under microscope. The cell and vascular structure of the second internode were observed and measured under Olympus IX81 fluorescent inverted microscope (Shanghai AIyan Biotechnology Co., Ltd., Shanghai, China).
Figure 5. Cell and vascular structure under microscope. The cell and vascular structure of the second internode were observed and measured under Olympus IX81 fluorescent inverted microscope (Shanghai AIyan Biotechnology Co., Ltd., Shanghai, China).
Agronomy 15 00699 g005
Table 1. Stem morphological features of different Japonica rice varieties.
Table 1. Stem morphological features of different Japonica rice varieties.
VarietyGravity Center
Height/cm		Second SegmentThird SegmentSecond SheathThird Sheath
Length/cmWeight/gLength/cmWeight/gLength/cmWeight/gLength/cmWeight/g
LY105242.19 c12.61 b1.90 a20.10 b1.92 a23.53 b0.91 a23.25 b1.82 a
LY990644.21 b11.38 c1.20 b16.73 d1.18 b22.20 c0.67 b22.88 b0.69 c
GY144.43 b11.35 c0.98 d18.25 c1.05 c22.39 c0.46 c21.15 c1.60 b
NL31347.32 a13.58 a1.12 c21.25 a1.06 c24.64 a0.62 b26.16 a0.52 d
Within a column for each stem morphological feature, means followed by the different small alphabetical letters show significant differences among the four varieties according to the least significant difference test at the 95% level of confidence.
Table 2. Cell and vascular structure of second stem.
Table 2. Cell and vascular structure of second stem.
VarietyCell StructureVascular Structure
Tissue
Layer Number		Tissue
Thickness/μm		Cell
Layer Number		Cell Thickness/μmCross Area
/cm2		Large Vascular
Number		Small Vascular
Number		Large Vascular Area/μm2Small Vascular Area/μm2
LY105220.80 c638.39 c3.50 a23.30 c0.10 b30.10 b29.30 c14,536.34 c8374.65 b
LY990622.90 b656.66 b3.50 a26.85 b0.12 a31.80 a30.40 b176,653.71 b8628.32 b
GY124.00 a678.73 a3.50 a27.65 a0.11 ab31.30 a31.40 a20,765.19 a10,242.07 a
NL31319.10 d550.77 d3.20 a17.11 d0.09 c29.00 c25.30 d11,078.46 d5385.54 c
Within a column for each cell and vascular structure, means followed by the different small alphabetical letters show significant differences among the four varieties according to the least significant difference test at the 95% level of confidence.
Table 3. Chemical composition of stem and sheath.
Table 3. Chemical composition of stem and sheath.
VarietyStemSheath
Cellulose
/(%)		Lignin
/(%)		Silicon
/(%)		Potassium
/(%)		Cellulose
/(%)		Lignin
/(%)		Silicon
/(%)		Potassium
/(%)
LY105234.16 b1.15 c0.02 c1.26 c33.39 a2.18 b0.04 c0.68 c
LY990638.70 a3.42 a0.04 a1.75 b29.83 c3.26 a0.04 a0.67 c
GY138.08 a2.99 b0.04 a2.25 a32.77 ab1.25 d0.04 bc1.04 a
NL31325.07 c1.17 c0.03 b0.71 d32.59 b1.62 c0.04 ab0.82 b
Within a column for each chemical composition of stem and sheath, means followed by the different small alphabetical letters show significant differences among the four varieties according to the least significant difference test at the 95% level of confidence.
Table 4. Mechanical properties of stem internode.
Table 4. Mechanical properties of stem internode.
VarietyMax Bending Resistance/NBreaking Moment
/N·cm		Bending Section Coefficient/cm3Single Stem Weight
Mass Moment
/N·cm		Bending Strength
/N·cm−2		Young’s Elastic Modulus/N·cm−2Inertia Moment/cm4Lodging Index
LY105210.18 c19.29 c2.1 × 10−2 b13.89 b906.91 b7.69 × 104 c6.7 × 10−3 b0.72 b
LY990610.73 b20.55 b2.1 × 10−2 ab13.36 b948.38 ab8.13 × 104 b6.6 × 10−3 c0.65 c
GY111.75 a21.44 a2.2 × 10−2 a12.65 d970.18 a8.85 × 104 a6.5 × 10−3 c0.59 d
NL3136.40 d15.93 d1.8 × 10−2 c24.38 a770.72 c6.01 × 104 d7.2 × 10−3 a1.53 a
Within a column for each mechanical properties of stem internode, means followed by the different small alphabetical letters show significant differences among the four varieties according to the least significant difference test at the 95% level of confidence.
Table 5. Correlation between lodging index and lodging related characters.
Table 5. Correlation between lodging index and lodging related characters.
Lodging-Related CharacteristicsCorrelation
Coefficient		Lodging-Related CharacteristicsCorrelation
Coefficient
Features of rice paniclesPanicle numbers0.925Features of plant typePlant height−0.989 *
Panicle inner cut angle0.952 *Base angle of flag leaf0.864
Panicle outer cut angle0.957 *Open angle of flag leaf0.823
Panicle length−0.683Base angle of penultimate leaf−0.504
Panicle extension length−0.487Open angle of penultimate leaf0.926
Single panicle fresh weight−0.911Base angle of antepenultimate leaf−0.220
Open angle of antepenultimate leaf0.376
Stem morphological featuresSecond internode length0.890Stem microstructureTissue thickness−0.984 *
Second internode weight−0.186Tissue layer−0.861
Second sheath length0.900Cell thickness−0.958 *
Second sheath weight−0.028Cell layer−0.993
Third internode length0.766Cross area−0.687
Third internode weight−0.279Large vascular number−0.866
Third sheath length0.940Small vascular number−0.979 *
Third sheath weight−0.631Large vascular area−0.859
Gravity center height0.819Small vascular area−0.951 *
Stem chemical compositionCellulose (stem)−0.972 *Stem mechanical propertiesMax bending force−0.986 *
Lignin (stem)−0.640Breaking moment−0.968 *
Silicon (stem)−0.281Bending section coefficient−0.983 *
Potassium (stem)−0.859Single stem weight
mass moment		0.998 **
Cellulose (sheath)0.211Bending strength−0.984 *
Lignin (sheath)−0.298Young’s elastic modulus−0.958 *
Silicon (sheath)0.400Inertia moment0.989 *
Potassium (sheath)−0.027
* and ** followed by correlation coefficient indicate the correlation between lodging characteristics and index at p < 0.05 and p < 0.01 level, respectively.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Zhang, L.; Ma, Z.; He, N.; Tang, Z.; Wang, C.; Zheng, W.; Wang, H.; Sui, G.; Gao, H.; Wang, L. Lodging Resistance of Japonica Hybrid Rice Plants Studied in Relation to Mechanical and Physicochemical Characteristics. Agronomy 2025, 15, 699. https://doi.org/10.3390/agronomy15030699

AMA Style

Zhang L, Ma Z, He N, Tang Z, Wang C, Zheng W, Wang H, Sui G, Gao H, Wang L. Lodging Resistance of Japonica Hybrid Rice Plants Studied in Relation to Mechanical and Physicochemical Characteristics. Agronomy. 2025; 15(3):699. https://doi.org/10.3390/agronomy15030699

Chicago/Turabian Style

Zhang, Liying, Zuobin Ma, Na He, Zhiqiang Tang, Changhua Wang, Wenjing Zheng, Hui Wang, Guomin Sui, Hong Gao, and Lili Wang. 2025. "Lodging Resistance of Japonica Hybrid Rice Plants Studied in Relation to Mechanical and Physicochemical Characteristics" Agronomy 15, no. 3: 699. https://doi.org/10.3390/agronomy15030699

APA Style

Zhang, L., Ma, Z., He, N., Tang, Z., Wang, C., Zheng, W., Wang, H., Sui, G., Gao, H., & Wang, L. (2025). Lodging Resistance of Japonica Hybrid Rice Plants Studied in Relation to Mechanical and Physicochemical Characteristics. Agronomy, 15(3), 699. https://doi.org/10.3390/agronomy15030699

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop