Pectin is a natural anionic polysaccharide, which is of great significance in agricultural applications, but its solubility in water limits its application. Pectin nanospheres can improve the dispersion of pectin in water. This work is to study the effects of pectin nanospheres on wheat germination and seedling growth. The pectin nanospheres were synthesized by ionotropic gelation. Meanwhile, the morphology of pectin nanospheres and the attachment on the surface of wheat seeds coat were characterized. The different concentrations (50, 100, 500 μg/mL) of pectin nanospheres were used to research the impact of wheat seed germination. In the concentration of 50 μg/mL pectin nanospheres treatment groups, the germination rate and seedling index got a 15.6% and 13.9% increase, respectively. The germination index increased by 22.1%, fresh weight of the aboveground part and underground part, respectively, increased by 26.7% and 17.3%, dry weight of the aboveground part and underground part, respectively, increased by 9.65% and 9.97%, and number of adventitious roots and the length of seedlings went up by 36.6% and 20.1%, respectively. Moreover, in seedlings stage the 100 μg/mL promoted the net photosynthetic rate of wheat by 60.2% and uptake of nutrient. In addition, energy-dispersive spectroscopy (EDS) confirmed the adsorption of pectin nanospheres on the surface of wheat seeds.

Chitosan oligosaccharides (COS) worked effectively in multiple plant-pathogen interactions as plant immunity regulator, however, due to the complexity of the COS-induced immune signaling network, the topic requires further investigation. In the present study, quantitative analysis of proteins was performed to investigate the underlying mechanism of COS induced resistance to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in Arabidopsis thaliana. 4303 proteins were successfully quantified, 186, 217 and 207 proteins were differently regulated in mock + Pst, COS, and COS + Pst treated plants, respectively, compared with mock plants. From detailed functional and hierarchical clustering analysis, a priming effect of COS on plant immune system by pre-regulated the key proteins related to signaling transduction, defense response, cell wall biosynthesis and modification, plant growth and development, gene transcription and translation, which confers enhanced resistance when Pst DC3000 infection in Arabidopsis. Moreover, RACK1B which has the potential to be the key kinase receptor for COS signals was found out by protein-protein interaction network analysis of COS responsive proteins. In conclusion, COS treatment enable plant to fine-tuning its defense mechanisms for a more rapid and stronger response to future pathogen attacks, which obviously enhances plants defensive capacity that makes COS worked effectively in multiple plant-pathogen interactions.

Calcium alginate (CaAlg) submicroparticles have a potential application in agricultural delivery systems. This study investigated the effects of CaAlg submicroparticles on seed germination and seedling growth of wheat. CaAlg submicroparticles with a Z-average diameter of around 250.4 nm and a measured zeta potential value of about −25.4 mV were prepared and characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDS). After this, the effects of the concentration of CaAlg submicroparticles (10–500 μg/mL) on germination percentage, seedling length, the number of adventitious roots, chlorophyll content and soluble protein content were evaluated. The results demonstrated a significant increase in the level of germination percentage (9.0%), seedling index (50.3%), adventitious roots (27.5%), seedling length (17.0%), chlorophyll (8.7%) and soluble protein contents (4.5%) at a concentration of 100 μg/mL. However, an inhibitory effect was observed at a concentration of 500 μg/mL. The SEM examination showed that CaAlg submicroparticles could be successfully adsorbed onto the surface of the wheat seed. Further studies proved that CaAlg submicroparticles at a concentration of 100 μg/mL promoted the expression of indole-3-acetic acid (IAA)-related genes (YUCCA9, AUX1, ARF and UGT) in wheat, which resulted in an increase of 69% and 21% in IAA concentration in wheat roots and shoots, respectively.

N-糖基化作为一种重要的蛋白质翻译后修饰,在胚胎发育、癌症发生发展及免疫防御等诸多复杂的生命活动中发挥着关键作用.近年来,基于质谱的N-糖链的检测及其定量研究在动物方面取得了显著进展,相比之下,植物N-糖基化及N-糖链检测的相关研究要远远滞后,这也是制约植物糖生物学研究发展的关键瓶颈问题之一.对蛋白质N-糖链的释放、定量策略、可视化检测及其在植物中的应用进展进行了归纳总结,以期为指导后续植物N-糖链及N-糖组的定性定量检测提供参考.