The Chinese rice–fish–duck symbiosis system is one of the globally important agricultural heritage systems, with a history of nearly a thousand years. It embodies the wisdom of the Chinese ancestors and has huge comprehensive value, which has extremely important references for the sustainable development of agriculture. The technological core for the rice–fish–duck symbiosis system lies in the selection of rice, fish, and duck varieties and the coupling of agricultural operation time. In the process of modern agriculture, many varieties with high comprehensive benefits have also been applied to the rice–fish–duck system, and the rice–fish–duck model has been further developed. What is worrying is that the transfer of rural labor, the promotion of modern agricultural technology, the low degree of marketization and industrialization, the weakening of cultural awareness, and the change in climate have posed huge threats and challenges to the traditional Chinese rice–fish–duck system. The protection and development of the system are urgently needed. Therefore, we recommend delimiting active protection areas, establishing scientific research bases, improving relevant systems, developing rural tourism markets, and innovating farming technology, which also provide guidance for protecting and developing other agricultural cultural heritages.

Panicle-stage nitrogen fertilizer is popular in parts of China due to its higher nitrogen recovery efficiency compared to basal and tiller nitrogen. However, the effect of conversion from basal to panicle-stage nitrogen on matter production, grain yield, and nitrogen use efficiencies (NUE) in Chinese double-cropping rice systems remains largely unknown. Here, we elucidate the effect by using two types of one-time basal nitrogen patterns (A and B), three panicle-N allocation patterns (C, D, and E), and the local conventional patterns (CK). The two-year experiment demonstrates that E (basal/tiller/spikelet-promoting /spikelet-developing nitrogen = 0:4:3:3) produced the greatest annual grain yield, nitrogen agronomic efficiency, and nitrogen partial productivity. The annual dry matter weight and nitrogen increment of panicle, nitrogen transportation of stems contributes the most to annual yield and NUE. Furthermore, the yield increase could be attributed to the higher effective panicles, plant dry matter weight at tillering, and net photosynthesis rate at heading. Moreover, years and varieties affect the yield in different N treatments. The improvement in the net photosynthesis rate at the milk stage also significantly increases nitrogen recovery efficiency. These findings suggest that it is worth paying attention to the rational ratio of tillering to panicle fertilizer without applying a base fertilizer, to synchronously increase the grain yield, NUE in Chinese double-cropping rice systems.

In order to evaluate the effects of climatic conditions on maize grain yield (GY), kernel weight (KW), and kernel filling and identify the optimal climatic factors for GY and KW, 2-year field experiments in three seasons, i.e., spring (S_PM), summer (S_UM), and autumn (A_UM), on maize were conducted in Central China. The results showed that S_UM had more growing degree days (GDDs) than S_PM and A_UM due to the higher mean temperature (MT), and also resulted in higher temperature stress (killing degree days (KDDs)) in maize growth duration. Meanwhile, after silking, S_PM and S_UM had more GDDs and KDDs than A_UM because of the higher MT, and the accumulated solar radiation (Ra) for S_UM was significantly higher than for S_PM and A_UM. The GY of S_PM was significantly higher than that of S_UM and A_UM, while S_UM’s GY was always the lowest, because the GDD_GD, MT_GD, and KDD_GD played significantly negative roles on GY. The final KW for S_UM was always the lowest, with GDD, MT, KDD, and Ra causing significantly negative effects, and M△T and precipitation having significant positive effects, resulting in a lower kernel filling rate during the linear kernel filling period (KFR_lkf) and a lower GDD at the maximum kernel filling rate (GDD_KFRmax). Maize KFR_lkf has significant negative linear dependences on GDD, MT, and Ra. In summary, because of the higher MT, KDD, and GDD during maize growth and kernel filling duration negatively affecting the maize kernel filling rate, the GY and KW for S_PM were the highest, and for S_UM, they were the lowest; therefore, farmers should plant S_PM first and then A_UM in Central China.

Modified biochars have attracted attention for reducing greenhouse gas emissions in paddy fields. However, material screening difficulties and lengthy effect validation periods have restricted their development. We proposed a theoretical calculation method to guide short-term field trials in this study. Utilizing first-principles calculations, we determined that sodium ferrate-modified biochar (Fe@C) would limit methane (CH₄) and nitrous oxide (N₂O) emissions. Field trials confirmed that Fe@C increased rice yields and active organic carbon content in soil and reduced methane emissions and the global warming potential. However, applying sodium ferrate alone significantly reduced N₂O emissions. Correlation analysis showed that methane was significantly negatively correlated with yield and the soil carbon pool labile index. N₂O was significantly negatively correlated with urease activity, and significantly positively correlated with the soil carbon pool management index. Therefore, Fe@C provides a high-yielding management measure that enhances soil labile organic carbon. Additionally, its effects were controlled by the proportion of sodium ferrate. Our work provides a new strategy to guide the design of paddy field experiments via theoretical calculations, greatly shortening research time and providing solutions for carbon sequestration and emissions reduction.

Minipigs have become important biomedical models for human ailments due to similarities in organ anatomy, physiology, and circadian rhythms relative to humans. The homeostasis of circadian rhythms in both central and peripheral tissues is pivotal for numerous biological processes. Hence, biological rhythm disorders may contribute to the onset of cancers and metabolic disorders including obesity and type II diabetes, amongst others. A tight regulation of circadian clock effectors ensures a rhythmic expression profile of output genes which, depending on cell type, constitute about 3–20% of the transcribed mammalian genome. Central to this system is the negative regulator protein Cryptochrome 1 (CRY1) of which the dysfunction or absence has been linked to the pathogenesis of rhythm disorders. In this study, we generated transgenic Bama-minipigs featuring expression of the Cys414-Ala antimorphic human Cryptochrome 1 mutant (hCRY1^AP). Using transgenic donor fibroblasts as nuclear donors, the method of handmade cloning (HMC) was used to produce reconstructed embryos, subsequently transferred to surrogate sows. A total of 23 viable piglets were delivered. All were transgenic and seemingly healthy. However, two pigs with high transgene expression succumbed during the first two months. Molecular analyzes in epidermal fibroblasts demonstrated disturbances to the expression profile of core circadian clock genes and elevated expression of the proinflammatory cytokines IL-6 and TNF-α, known to be risk factors in cancer and metabolic disorders.