Abstract:

This study used parents A8450, Yangtai A, and R128 as materials, to explore the impact of three-dimensional industrial seedling raising on the characteristics of parents in hybrid rice seed production. Three seedling-raising methods were set up:“W”-shaped three-dimensional circular industrial seedling tray raising, field seedling tray raising, and traditional wet bed seedling raising. Five seedling age treatments were designed under each method. The differences in seedling quality, growth characteristics, maximum seedling number, and spike-grain structure among different treatments were systematically compared. The results showed that the overall seedling quality of“W”-shaped three-dimensional circular industrial seedling raising was relatively poor. The leaf emergence rate slowed down after 14 days of seedling age. By 26 days of seedling age, the leaf age did not exceed 2.6 leaves, the seedling height was lower than 20 cm, the basal stem width was less than 2.6 mm, and the plants were relatively weak. In contrast, the seedling quality of field seedling tray raising and traditional wet bed seedling raising was good during the same period. After transplanting to the field, the differences in characteristics among different treatments narrowed. The variation range of the number of main stem leaves was within 0.6 leaves, and there were no significant differences in the number of effective panicles per hill, maximum seedling number, panicle length, and total grains per panicle. Industrial seedling raising had a significant impact on the duration from sowing to heading of the parents, with the order being“W”-shaped three-dimensional circular industrial seedling raising≥field seedling tray raising≥traditional wet bed seedling raising. Moreover, as the seedling age extended, the duration from sowing to heading of the industrial seedling raising treatment increased to a greater extent. In addition, the total grains per hill of“W”-shaped three-dimensional circular industrial seedling raising were 1.48%-9.82% lower than those of field seedling tray raising and 8.41%-19.85% lower than those of traditional wet bed seedling raising. In conclusion,“W”-shaped three-dimensional circular industrial seedling raising can be used for seedling cultivation of parents in hybrid rice seed production, especially helping to alleviate problems such as seedling rot, low seedling survival rate, and poor uniformity that are prone to occur in field mechanical transplanting seedling raising under low-temperature conditions. However, attention should be paid to the impact of its extended duration from sowing to heading during application. The sowing and transplanting dates should be adjusted in a timely manner, and cultivation measures should be taken to increase the total grains per hill. The results of this study can provide technical basis and scientific reference for the promotion and application of three-dimensional industrial seedling raising technology in hybrid rice seed production.

Key words: hybrid rice, seed production, three-dimensional factory seedling raising, seedling quality, growth period, economic traits

摘要：

为探究立体工厂化育秧对杂交水稻制种亲本特性的影响，本研究以亲本A8450、扬泰A和R128为材料，设置“W”型立体循环工厂化秧盘育秧、大田秧盘育秧和传统湿润水育秧共3种育秧方式，每种方式下设5个秧龄处理，系统比较了不同处理下秧苗素质、生育特性、最高苗数及穗粒结构等性状的差异。结果表明，“W”型立体循环工厂化育秧的秧苗素质整体较差，14 d秧龄后出叶速度减缓，至26 d秧龄时叶龄不超过2.6叶，苗高低于20 cm，茎基宽小于2.6 mm，植株较为弱小；而同期大田秧盘育秧和传统湿润水育秧的秧苗素质均较好。移栽至大田后，各处理间性状差异缩小，主茎叶片数变幅在0.6叶以内，单穴有效穗数、最高苗数、穗长及穗平总粒数均无显著差异。工厂化育秧对亲本播始历期影响显著，表现为“W”型立体循环工厂化育秧≥大田秧盘育秧≥传统湿润水育秧，且随着秧龄延长，工厂化育秧处理的播始历期延长幅度更大。“W”型立体循环工厂化育秧的单穴总粒数较大田秧盘育秧低1.48%~9.82%，较传统湿润水育秧低8.41%~19.85。综上，“W”型立体循环工厂化育秧可用于杂交水稻制种亲本育苗，尤其有助于缓解大田机插育秧在低温条件下易出现的烂秧、成秧率低和整齐度差等问题；但在应用中需注意其播始历期延长的影响，应适时调整播插期并采取栽培措施提高单穴总粒数。本研究结果可为立体工厂化育秧技术在杂交水稻制种中的推广应用提供技术依据和科学参考。

关键词: 杂交水稻, 制种, 立体工厂化育秧, 秧苗素质, 生育期, 经济性状