Ren Yun, Zhu Jianfang, Zhang Hui, Lin Baogang, Hao Pengfei, Hua Shuijin
Huzhou Agricultural Science and Technology Development Center, Huzhou Academy of Agricultural Sciences, Huzhou 313000, China.
Zhejiang Agro-Tech Extension and Service Center, Hangzhou 310020, China.
Plants (Basel). 2022 Jun 27;11(13):1696. doi: 10.3390/plants11131696.
Delayed planting date of rapeseed is an important factor affecting seed yield. However, regulation of the leaf carbohydrate metabolism in rapeseed by a late planting date at the reproductive stage is scarcely investigated. A two-year field experiment was conducted to assess the effect of planting dates, including early (15 September), optimal (1 October), late (15 October), and very late (30 October), on leaf growth and carbohydrate biosynthetic and catabolic metabolism at the reproductive stage. The results showed that leaf dry matter decreased linearly on average from 7.48 to 0.62 g plant with an early planting date, whereas it increased at first and peaked at 14 days after anthesis (DAA) with other planting dates. Leaf dry matter was the lowest at the very late planting date during the reproductive stage. For leaf chlorophyll content, rapeseed planted at an optimal date maximized at 14 DAA with an average content of 1.51 mg g fresh weight, whereas it kept high and stable at a very late planting date after 28 DAA. For the carbohydrate catabolic system, acid and neutral invertase (AI and NI, respectively) showed higher activity before 14 DAA, whereas both sucrose synthase (SS) and starch phosphorylase (SP) showed higher activity after 14 DAA. For the carbohydrate biosynthetic system, the activity of sucrose phosphate synthase (SPS) was the highest at the late planting date after 14 DAA, whereas it was at the lowest at the very late planting date. However, the activity of ADP-glucose pyrophosphorylase (AGPase) at the late and very late planting dates was significantly higher than that of the early and optimal plant dates after 21 DAA, which is in accordance with the leaf total soluble sugar content, suggesting that leaf carbohydrate metabolism is governed by a biosynthetic system. The current study provides new insights on leaf carbohydrate metabolism regulation by late planting in rapeseed at the reproductive stage.
油菜播种期延迟是影响种子产量的重要因素。然而，关于生殖阶段延迟播种对油菜叶片碳水化合物代谢的调控研究甚少。开展了一项为期两年的田间试验，以评估不同播种期（包括早播（9月15日）、适播（10月1日）、晚播（10月15日）和极晚播（10月30日））对生殖阶段叶片生长以及碳水化合物合成与分解代谢的影响。结果表明，早播时叶片干物质平均从7.48克/株线性下降至0.62克/株，而其他播种期叶片干物质先增加，在开花后14天（DAA）达到峰值。生殖阶段极晚播时叶片干物质最低。对于叶片叶绿素含量，适播期种植的油菜在14 DAA时达到最大值，平均含量为1.51毫克/克鲜重，而极晚播时在28 DAA后保持高且稳定。对于碳水化合物分解系统，酸性和中性转化酶（分别为AI和NI）在14 DAA之前活性较高，而蔗糖合酶（SS）和淀粉磷酸化酶（SP）在14 DAA之后活性较高。对于碳水化合物合成系统，蔗糖磷酸合酶（SPS）的活性在14 DAA后的晚播期最高，而在极晚播期最低。然而，在21 DAA后，晚播和极晚播期的ADP - 葡萄糖焦磷酸化酶（AGPase）活性显著高于早播和适播期，这与叶片总可溶性糖含量一致，表明叶片碳水化合物代谢受合成系统调控。本研究为油菜生殖阶段延迟播种对叶片碳水化合物代谢的调控提供了新的见解。
