To clarify the influence of exogenous alpha-ketoglutaric acid (α-KG) spraying after anthesis on the photosynthesis of wheat flag leaves and the characteristics of grain filling, Shumai 830 and Shumai 1868, with significant differences in thousand-grain weight, were selected as materials. Using no spraying as the contrel (CK), 0.50, 0.75, and 1.00 g·L-1 concentrations of α-KG spraying at 0 d and 15 d after anthesis were set up. The differences in chlorophyll content and photosynthetic parameters of flag leaves, grain-filling parameters, and yield under different treatments were compared. The results indicated that compared with the CK, the α-KG treatment enhanced wheat photosynthesis and promoted grain filling, thereby increasing the grain weight of wheat. Among them, the treatment of 0.75 g·L-1 α-KG showed the best effects. Under the treatment with 0.75 g·L-1 of α-KG, the chlorophyll content at 21 d after anthesis and the net photosynthetic rate at 20 d after anthesis of Shumai 830 and Shumai 1868 were significantly higher than those of the CK, with an increase rate of 12.0% and 9.6% for chlorophyll content, and 11.1% and 6.6% for net photosynthetic rate, respectively. And the active grain-filling period, average grain-filling rate, and maximum theoretical thousand-grain weight of Shumai 830and Shumai 1868 were significantly higher than those of the CK, with an increase rate of 3.8%, 4.6%, and 7.9% for Shumai 830, and 1.6%, 4.9%, and 4.9% for Shumai 1868. After the treatment with 0.75 g·L-1 of α-KG, the thousand-grain weight of Shumai 830 and Shumai 1868 was increased by 3.8% and 2.7%, respectively, compared with CK, and the yield was increased by 6.2% and 7.9%, respectively, all showing significant difference from the CK. Thus, exogenous α-KG spraying after anthesis can promote photosynthesis and grain filling by increasing the chlorophyll content of wheat, and ultimately increase grain weight and yield.
| 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 |