Recently, researchers from Biotechnology Research Institute (BRI) of Chinese Academy of Agricultural Sciences (CAAS), in collaboration with South China Agricultural University etc. reported their research results in a paper entitled “Localauxinbiosynthesisregulates brace root angle and lodging resistance in maize” published in the internationally reputed journal “New Phytologist”.
Root lodging poses a major threat to maize production, resulting in reduced grain yield andquality, and increased harvest costs. Here, researcherscombined expressional, genetic, and cytological studies to demonstrate a role ofZmYUC2 and ZmYUC4 in regulating gravitropic response of the brace root and lodging resistancein maize. They show that both ZmYUC2 and ZmYUC4 are preferentially expressed in root tips withpartially overlapping expression patterns, and the protein products of ZmYUC2 and ZmYUC4are localized in the cytoplasm and endoplasmic reticulum, respectively. The Zmyuc4 singlemutant and Zmyuc2/4 double mutant exhibit enlarged brace root angle compared with thewild-type plants, with larger brace root angle being observed in the Zmyuc2/4 doublemutant. Consistently, the brace root tips of the Zmyuc4 single mutant and Zmyuc2/4 doublemutant accumulate less auxin and are defective in proper reallocation of auxin in response togravi-stimuli. Furthermore, they show that the Zmyuc4 single mutant and the Zmyuc2/4 doublemutant display obviously enhanced root lodging resistance.These combined results demonstrate that ZmYUC2- and ZmYUC4-mediated local auxinbiosynthesis is required for normal gravity response of the brace roots and provide effectivetargets for breeding root lodging resistant maize cultivars.
Doctoral studentZhigang Zheng (South China Agricultural University), Dr. Baobao Wang(BRI, CAAS), and master studentChuyun Zhuo(South China Agricultural University)are the co-first authors of this research. Professor Haiyang Wang (South China Agricultural University) is the corresponding author. This work is funded by by grants from the National Key Research and Development Programof China (2021YFF1000301 and 2020YFE0202300),National Natural Science Foundation of China (32272189) andHainan Yazhou Bay Seed Lab (B21HJ8101).
More information can be found through the link:https://nph.onlinelibrary.wiley.com/doi/10.1111/nph.18733
Figure 1.Enhanced root lodging resistance in the Zmyuc4 and Zmyuc2/4 mutants. |