College of Agriculture, South China Agricultural University, Guangzhou, 510642, Guangdong, China.
Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 434007, Guangdong, China.
BMC Plant Biol. 2023 Apr 11;23(1):194. doi: 10.1186/s12870-022-03954-6.
Improving the yield and aroma content of fragrant rice is the focus of fragrant rice research. Light and Zinc (Zn) management generally cause regulations in the 2-acetyl-1-pyrroline (2AP) accumulation in fragrant rice. In addition, Zn promotes rice growth and improves rice yield, which has the potential to compensate for the negative impact of low light on fragrant rice yield. However, the potential of Zn to improve fragrant rice yield and 2AP content under shading conditions has not been verified.
Field experiments were conducted in the rice season (May-September) in 2019 to 2021. Two light i.e., normal light (NL) and low light (LL) and four Zn levels i.e., 0 kg Zn ha (N0), 1 kg Zn ha (Zn1), 2 kg Zn ha(Zn2), and 3 kg Zn ha (Zn3), which applied at booting stage was set up. The grain yield, 2AP contents, Zn content in polished rice, photosynthesis related indicators, MDA content, antioxidant enzyme activity and the biochemical parameters related to 2AP formation were investigated.
Shading reduced yield by 8.74% and increased 2AP content by 24.37%. In addition, shading reduced net photosynthetic rate (Pn), superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and increased proline, γ-aminobutyric acid (GABA), and pyrroline-5-carboxylic acid (P5C), proline dehydrogenase (PDH), △1-pyrroline-5-carboxylic acid synthetase (P5CS), malondialdehyde (MDA). With increasing Zn application levels, yield, 2AP, Zn content in polished rice, Pn, proline, P5C, GABA, PDH, P5CS, SOD, CAT and POD increased, and MDA decreased. Significant Light and Zn interaction effect on 2AP content was detected, and both shading and increasing Zn application increased the 2AP content.
Shading can increase the 2AP content but reduce the yield of fragrant rice. Increasing Zn application under shading conditions can further promote the biosynthesis of 2AP, but the effect of improving yield is limited.
提高香稻的产量和香气含量是香稻研究的重点。光照和锌（Zn）管理通常会导致香稻中 2-乙酰-1-吡咯啉（2AP）积累的调节。此外，Zn 促进水稻生长，提高水稻产量，有可能弥补低光照对香稻产量的负面影响。然而，Zn 提高遮荫条件下香稻产量和 2AP 含量的潜力尚未得到验证。
2019 年至 2021 年在水稻季（5 月至 9 月）进行田间试验。设置了两种光照，即正常光照（NL）和低光照（LL）和四种 Zn 水平，即 0 kg Zn ha（N0）、1 kg Zn ha（Zn1）、2 kg Zn ha（Zn2）和 3 kg Zn ha（Zn3），在孕穗期施用。研究了籽粒产量、2AP 含量、精米中的 Zn 含量、光合作用相关指标、MDA 含量、抗氧化酶活性以及与 2AP 形成相关的生化参数。
遮荫使产量降低了 8.74%，2AP 含量增加了 24.37%。此外，遮荫降低了净光合速率（Pn）、超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT），增加了脯氨酸、γ-氨基丁酸（GABA）和吡咯啉-5-羧酸（P5C）、脯氨酸脱氢酶（PDH）、△1-吡咯啉-5-羧酸合成酶（P5CS）、丙二醛（MDA）。随着 Zn 施用量的增加，产量、2AP、精米中的 Zn 含量、Pn、脯氨酸、P5C、GABA、PDH、P5CS、SOD、CAT 和 POD 增加，MDA 降低。光照和 Zn 处理对 2AP 含量有显著的互作效应，遮荫和增加 Zn 施用量均增加了 2AP 含量。
遮荫会增加 2AP 含量，但会降低香稻的产量。在遮荫条件下增加 Zn 施用量可以进一步促进 2AP 的生物合成，但提高产量的效果有限。
