Rice Genomics and Genetics 2025, Vol.16, No.2, 71-85 http://cropscipublisher.com/index.php/rgg 82 in Leshan Pingba showed that the yield of the 30 cm×12 cm configuration (one seedling per hole) was better than that of the 25 cm×16 cm configuration, indicating that appropriately increasing the row spacing and increasing the hole density are more conducive to increasing yield. These practical details and experiences enrich the application methods of density optimization and provide a reference for promoting high-yield technology of dense planting under different terrain conditions. 6.3 Comparative analysis and key takeaways The two cases of Nanchang and plain rice areas and Leshan hilly rice areas represent two different ecological types, and the needs and strategies for density optimization are different: the former focuses on reducing density to prevent lodging, stabilize yield and improve quality, while the latter focuses on increasing density to tap potential, increase yield and increase efficiency. But the common point between the two is that they have achieved substantial results by adjusting the basic seedlings and planting methods, proving that density optimization plays an important role in different environments. At the same time, the case also reflects that density management needs to be combined with other agronomic measures. For example, in the Nanchang case, if the control measures are not taken, simply reducing the density may reduce the yield, so the density was reduced and ear fertilizer was applied appropriately early to make up for the number of grains per ear; in the Leshan case, if there is no mechanical single-planting and wide and narrow row support, simply increasing the density is also difficult to work. This reminds us that the optimization of planting density should be considered as a part of the integrated high-yield cultivation technology system, and it should be considered in conjunction with variety selection, seedling raising methods, fertilizer and water management, etc., in order to achieve the best results in practice. For plain areas, attention should be paid to the impact of density on the stable yield of the group, and moderately dense planting but not over-dense should be used to ensure strong plant type and resistance to lodging; for hilly areas and areas with low yields, dense planting technology should be used to improve group productivity, but it is necessary to prevent over-dense planting from causing insufficient resources (Lei et al., 2025). In practical promotion, demonstration experiments should be strengthened and density optimization paradigms should be formulated according to regional characteristics. For example, basic rice seedling indicators and operating procedures for different production areas should be formulated for farmers to refer to and implement. At the same time, the success of the case also shows that density optimization is a measure with low investment and quick results. It is very suitable for promotion and application in large rice-growing areas, providing support for increasing rice production and farmers' income. 7 Concluding Remarks Reasonable dense planting is one of the key measures to achieve high rice yields. By moderately increasing the planting density, the number of effective panicles and total spikelets per unit area can be increased, thereby significantly increasing yield. However, there is a critical value in the relationship between density and yield. If the density is too high, the yield will decrease due to the inhibition of single plant development, the number of grains per panicle, and the decrease in fruiting rate. Therefore, it is necessary to determine the optimal density range under variety and environmental conditions to achieve the best balance between panicle number and panicle type. Density optimization requires a comprehensive consideration of the coordinated development of the group and the individual. Appropriate density helps to build a group structure with high photosynthetic efficiency and healthy and robust individuals. Under dense planting conditions, the utilization of light energy and dry matter accumulation of the group increase, but individual competition is also more intense; sparse planting is the opposite. The essence of optimizing density is to maximize the production capacity of the group without significantly weakening the panicle formation and filling capacity of the individual plant. To achieve this, it is also necessary to combine it with fertilizer and water management, and coordinate the source-sink relationship and the reproductive process.
RkJQdWJsaXNoZXIy MjQ4ODYzNA==