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Dihydrogibberellin (DIH) is an eco‐friendly and low‐toxic regulator with immense potential for application in the current rice industry, specifically for increasing yield and lodging resistance. However, limited research has been conducted to explore the impact of DIH on the yield and lodging resistance of direct‐seeded rice (DSR, Oryza sativa L.). Therefore, a 2‐year field experiment was conducted to evaluate the effects of spraying different concentrations of 5% DIH emulsifiable concentrate on DSR during the tillering (1) and jointing (2) stages. Three concentrations of DIH were used: 27 (DIH27), 54 (DIH54), and 108 g ha−1 (DIH108). The commonly used paclobutrazol concentration in rice production (112.5 g ha−1) was compared and a clear water treatment was used as control (CK). The results of the experiment showed that the DIH treatments increased the DSR yield by 1.22%–22.64% and reduced lodging index by 8.9%–54.2% compared to the CK treatment. Additionally, the DIH treatments resulted in significant reductions in the length of the 1–3 basal internodes and plant height, as well as increases in the diameter and culm wall thickness of internodes. Moreover, the DIH treatments also led to higher dry matter percentages in stalks and leaf sheaths, as well as increased lignin and cellulose content. Furthermore, the best effect of DIH application was observed at the jointing stage in terms of increasing yield and lodging resistance. Therefore, this research demonstrates that the application of DIH to DSR at the jointing stage can be an effective strategy for increasing yield and improving lodging resistance. Core Ideas: Spraying dihydrogibberellin effectively improved the lodging resistance of direct‐seeded rice.Spraying dihydrogibberellin at jointing stage can significantly boost the lodging resistance of direct‐seeded rice.The lodging and rice grain yield effects of dihydrogibberellin and paclobutrazol are compared. [ABSTRACT FROM AUTHOR]

One of the most destructive diseases, Gibberella stalk rot (GSR), caused by Fusarium graminearum, reduces maize yields significantly. An induced resistance response is a potent and cost-effective plant defense against pathogen attack. The functional counterpart of JAs, coronatine (COR), has attracted a lot of interest recently due to its ability to control plant growth and stimulate secondary metabolism. Although several studies have focused on COR as a plant immune elicitor to improve plant resistance to pathogens, the effectiveness and underlying mechanisms of the suppressive ability against COR to F. graminearum in maize have been limited. We investigated the potential physiological and molecular mechanisms of COR in modulating maize resistance to F. graminearum. COR treatment strongly enhanced disease resistance and promoted stomatal closure with H2O2 accumulation, and 10 μg/mL was confirmed as the best concentration. COR treatment increased defense-related enzyme activity and decreased the malondialdehyde content with enhanced antioxidant enzyme activity. To identify candidate resistance genes and gain insight into the molecular mechanism of GSR resistance associated with COR, we integrated transcriptomic and metabolomic data to systemically explore the defense mechanisms of COR, and multiple hub genes were pinpointed using weighted gene correlation network analysis (WGCNA). We discovered 6 significant modules containing 10 candidate genes: WRKY transcription factor (LOC100279570), calcium-binding protein (LOC100382070), NBR1-like protein (LOC100275089), amino acid permease (LOC100382244), glutathione S-transferase (LOC541830), HXXXD-type acyl-transferase (LOC100191608), prolin-rich extensin-like receptor protein kinase (LOC100501564), AP2-like ethylene-responsive transcription factor (LOC100384380), basic leucine zipper (LOC100275351), and glycosyltransferase (LOC606486), which are highly correlated with the jasmonic acid–ethylene signaling pathway and antioxidants. In addition, a core set of metabolites, including alpha-linolenic acid metabolism and flavonoids biosynthesis linked to the hub genes, were identified. Taken together, our research revealed differentially expressed key genes and metabolites, as well as co-expression networks, associated with COR treatment of maize stems after F. graminearum infection. In addition, COR-treated maize had higher JA (JA-Ile and Me-JA) levels. We postulated that COR plays a positive role in maize resistance to F. graminearum by regulating antioxidant levels and the JA signaling pathway, and the flavonoid biosynthesis pathway is also involved in the resistance response against GSR. [ABSTRACT FROM AUTHOR]

In our previous work, compound Y9k, 1-phenethyl-3- (3-(trifluoromethyl) phenyl) urea, displayed significant inhibition activity on root growth of Arabidopsis. To further investigate the application of urea compounds, a series of novel urea derivatives O1-O22 were designed and synthesized. The biological evaluation demonstrated that compounds O3, O11 and O13 exhibited excellent inhibition activity on root growth and the inhibition activity of O13 to the root growth of Arabidopsis was 2 orders of magnitude higher than that of the commercial herbicide clopyralid. Herbicidal activity assessment indicated that O13 displayed significant inhibition activity on weeds, especially in Amaranthus retroflexus. Furthermore, the morphological investigation of the auxin reporter (DR5::GUS) revealed that O13 could significantly enhanced transcriptional activity of auxin response reporter. These results suggested that O13 could be a promising scaffold for the discovery of novel auxin-related herbicide, and showed potentiality in crop protection from weeds. [ABSTRACT FROM AUTHOR]

The use of 1,1-dimethyl-piperidinium chloride (DPC) in Xinjiang is one of the necessary measures for regulating cotton populations and optimizing canopy structure. However, mechanical spraying involves operation and energy consumption, which can alternatively be achieved via drip application. In the present study, to investigate the effect of drip application, two types of hydrophobic nano-released DPCs were used to regulate plant type at different dosages. DPC dripingation reduced plant height by more than 10 cm and plant width by more than 4 cm, and the effect improved with increasing concentration and times. The main effect of height control was at the 6th–10th nodes of the main stem, and the effect of width control was observed at the 1st and 2nd nodes of the fruit branch. The SPAD value was higher than that in the control group during the initial stages. An irregular downward trend was observed in the subsequent stages. The proline content was higher than that of the control and increased with higher concentrations of DPC. There was no significant difference in the soil DPC content at the different sites. The DPC content decreased by more than 30% at the seventh day after dripping, and the content was 2–4 μg·g−1 in each treatment. At 15 days after application, the soil DPC was lower than 1 μg·g−1 in all treatments. The number of harvested plants was more than 150,000 plants·hm−2, and the number of bolls per plant increased at least by one, compared with the control. The final yield of seed cotton increased by at least 300 kg·hm−2, with a maximum increase of 1672.01 kg·hm−2. Considering the different types of DPCs, nano-released types worked better than the conventional type in terms of plant height, plant width, degradation in soil and boll formation. Nano-released DPC can play an even better role than conventional DPC in chemical regulation with drip irrigation. [ABSTRACT FROM AUTHOR]