关键词: 热区, 葡萄, 不正常花序, 花序质量, 调查与评价

Abstract:

【Objective】In recent years, with the promotion of rain-shelter cultivation and double cropping techniques, grape production in hot zones has achieved off-season and high-efficiency production. However, hot-region grapes face problems such as poor flower bud differentiation, uneven germination, and "flower running", which are the main constraints on stable and high-quality production. This study aims to systematically investigate and evaluate the inflorescence attachment characteristics and development quality of 98 grape germplasms in hot zones Guangxi, clarify the adaptability differences among different germplasms in hot zones, and provide theoretical basis and technical guidance for variety breeding and production management.【Method】This study investigated and evaluated the germination rate, flower bud rate, shoot formation rate, number of inflorescences per shoot, inflorescence attachment node, inflorescence type and quality of 98 grape germplasms in hot zones Guangxi for two consecutive years, covering European, American, and European-American hybrids. It deeply analyzed the quality differences and patterns among different varieties and inflorescence attachment nodes.【Result】Under the treatment of hydrogen cyanamide, all 98 germplasms could germinate and form shoots smoothly, among which 92 varieties could form normal inflorescences. The average germination rate was 90.42%, the shoot formation rate was 92.13%, the flower bud rate was about 61.06%, and the average number of inflorescences per shoot was 1.67. However, abnormal inflorescences were quite prominent, with a total proportion of 40.56%. This study classified abnormal inflorescences into three major types: tendrils type, differentiation cessation type and trophic tissue type. Among them, the tendril type was the most common, further divided into one to five tendril types, and all investigated varieties had two tendrils type inflorescences; the differentiation cessation type included single head type (only scales or death point), tendrils death point type, and branch death point type; the trophic tissue type included branch tendril and leaf tendril types. Shine Muscat showed all abnormal types and were representative materials of high sensitivity. Among the 8 investigated nodes, the inflorescence attachment was most concentrated at the 3rd and 4th nodes, accounting for 27.99% and 27.06% of the total inflorescences, respectively. The abnormal inflorescence rate at the 3rd node was the lowest, only 17.22%. Further population analysis indicated that V. vinifera L.×V. labrusca L. had higher flower bud rates (68.60%), more inflorescences per shoot (about 1.8), and higher normal inflorescence rates than V. vinifera (flower bud rate 46.59%). Moreover, varieties with high germination rates, flower bud rates, and shoot formation rates had more inflorescences per shoot and significantly lower abnormal inflorescence rates.【Conclusion】The attachment node of inflorescences significantly affects their quality performance. Among them, the middle nodes, especially the 3rd node, had the lowest abnormal inflorescence rate. Therefore, in production, for varieties prone to abnormal inflorescences, it is recommended to prioritize the retention of inflorescences at the 3rd node. Varieties with high germination rates, flower bud rates, and shoot formation rates and more inflorescences per shoot are more likely to obtain normal and high-quality inflorescences. Different grape populations show significant differences in inflorescence development and abnormal occurrence. V. vinifera L.×V. labrusca L. perform better in hot zones, with higher flower bud rates and normal inflorescence proportions. They are recommended as the preferred germplasm resources for cultivation in hot zones.

Key words: hot zone, grape, abnormal inflorescences, quality of inflorescence, investigation and evaluation