Fang Hao, Huang Jinwei, Zhu Xiatong, Hassan Muhammad Ahmad, Ren Jin, Huang Jingyao, Zheng Baoqiang, Chen Xiang, Lin Feifei, Li Jincai
College of Agronomy, Anhui Agricultural University, Hefei 230036, China.
Rice Research Institute, Anhui Academy of Agricultural Sciences, Hefei 230041, China.
Plants (Basel). 2024 Aug 20;13(16):2311. doi: 10.3390/plants13162311.
Late spring coldness (LSC) is the main limiting factor threatening wheat yield and quality stability. Optimal nutrient management is beneficial in mitigating the harms of LSC by improving wheat root physiology. This study proposed a nutrient management strategy that postponed the application of phosphorus (P) and potassium (K), effectively strengthening wheat's defense against LSC. This experiment used the winter cultivar "Yannong19" (YN 19) as plant material for two consecutive years (2021-2022 and 2022-2023). Two fertilizer treatments were used: traditional P and K fertilizers application (R1: base fertilizer: jointing fertilizer = 10:0) and postponed P and K fertilizers application (R2: base fertilizer: jointing fertilizer = 5:5); wheat plants at the anther connective formation stage shifted to temperature-controlled phytotrons for normal (T0, 11 °C/4 h) and low temperatures (T1, 4 °C/4 h; T2, -4 °C/4 h) as treatments of LSC. The results showed that under low temperature (LT) treatment, compared with R1, the R2 treatment increased the concentrations of osmotic adjustment substances (soluble sugars and soluble protein contents by 6.2-8.7% and 3.0-8.9%), enhanced activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase activities by 2.2-9.1%, 6.2-9.7% and 4.2-8.4%), balanced the hormone concentrations (increased IAA and GA contents by 2.8-17.5% and 10.4-14.1% and decreased ABA contents by 7.2-14.3%), and reduced the toxicity (malondialdehyde, hydrogen peroxide content and O· production rate by 5.7-12.4%, 17.7-22.8% and 19.1-19.1%) of the cellular membranes. Furthermore, the wheat root physiology in R2 significantly improved as the root surface area and dry weight increased by 5.0-6.6% and 4.7-6.6%, and P and K accumulation increased by 7.4-11.3% and 12.2-15.4% compared to R1, respectively. Overall, the postponed application of P and K fertilizers enhanced the physiological function of the root system, maintained root morphology, and promoted the accumulation of wheat nutrients under the stress of LSC.
倒春寒（LSC）是威胁小麦产量和品质稳定性的主要限制因素。优化养分管理有助于通过改善小麦根系生理状况来减轻倒春寒的危害。本研究提出了一种推迟磷（P）和钾（K）施用的养分管理策略，有效增强了小麦对倒春寒的防御能力。本试验连续两年（2021—2022年和2022—2023年）以冬小麦品种“烟农19”（YN19）为试验材料。采用两种施肥处理：传统磷钾肥施用（R1：基肥∶拔节肥 = 10∶0）和推迟磷钾肥施用（R2：基肥∶拔节肥 = 5∶5）；在花药药隔形成期将小麦植株转移至人工气候箱，设置正常温度（T0，11℃/4小时）和低温（T1，4℃/4小时；T2，-4℃/4小时）处理模拟倒春寒。结果表明，在低温（LT）处理下，与R1相比，R2处理提高了渗透调节物质浓度（可溶性糖和可溶性蛋白含量分别提高6.2%—8.7%和3.0%—8.9%），增强了抗氧化酶活性（超氧化物歧化酶、过氧化物酶和过氧化氢酶活性分别提高2.2%—9.1%、6.2%—9.7%和4.2%—8.4%），平衡了激素浓度（吲哚乙酸和赤霉素含量分别提高2.8%—17.5%和10.4%—14.1%，脱落酸含量降低7.2%—14.3%），降低了细胞膜毒性（丙二醛、过氧化氢含量和超氧阴离子产生速率分别降低5.7%—12.4%、17.7%—22.8%和19.1%）。此外，与R1相比，R2处理的小麦根系生理状况显著改善，根表面积和干重分别增加5.0%—6.6%和4.7%—6.6%，磷和钾积累量分别增加7.4%—11.3%和12.2%—15.4%。总体而言，推迟磷钾肥施用增强了根系生理功能，维持了根系形态，促进了倒春寒胁迫下小麦养分的积累。
