In or der to under stand the difference of agronomic traits among different wheat varieties (lines) in Huang-Huai wheat region, this study analyzed 626 wheat varieties (lines) participated in the national wheat regional trials in the Huang-Huai wheat region from 2015 to 2023, focusing on seven traits: heading date, spikelet number, spike length, average length of rachis node, kernels per spike, plant height, and thousand-kernel weight. The results showed that in the southern zone of the Huang-Huai Wheat Region, heading date was positively correlated with kernels per spike and spikelet number; plant height was positively correlated with spike length and spikelet number; whereas no such correlations were observed in the northern zone. This indicates that dwarf plants with large spikes coordinated the reduction in plant height with a moderate delay in heading date, possibly achieving stable spike length and increased kernels per spike in the southern zone, ultimately leading to shorter average length of rachis node. There was no significant correlation between kernels per spike and thousand-kernel weight, suggesting possible synergistic improvement of both traits. In contrast, there is a significant negative correlation between the two traits in the northern zone, indicating a trade-off between two traits. Significant differences were observed between the southern and northern zones in spike and plant-related agronomic traits. Longer spikes and average rachis node length, more spikelets, greater thousand-kernel weights, earlier heading dates, and shorter plant heights were observed in the varieties (lines) from southern zone compared to those in northern zone. Phenotypic differences were also varied across provinces. Varieties (lines) bred by Henan breeding institutions exhibited the highest thousand-kernel weights and more spikelet numbers, with spike lengths only shorter than those from Jiangsu. Varieties bred by Shaanxi breeding institutions showed highest kernels per spike. Shandong varieties exhibited the shortest spikes and latest heading dates but were shorter in plant height than those from Jiangsu, Hebei, and Anhui province. Jiangsu varieties (lines) showed the longest spikes but the fewest spikelets and longest average rachis nodes. Based on the seven agronomic traits, the 626 varieties (lines) were classified into two major groups, which were further divided into four subgroups. Subgroup classification was associated with breeding provinces and agronomic traits. Varieties (lines) in subgroup 1-2 had more spikelet and kernels per spike, and great thousand-kernel weight. These advantages were mostly inherited from Zhoumai series varieties (lines), which can be used for genetic improvement of wheat spike traits.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |