Induced defense strategies of plants against Ralstonia solanacearum

Plants respond to Ralstonia solanacearum infestation through two layers of immune system (PTI and ETI). This process involves the production of plant-induced resistance. Strategies for inducing resistance in plants include the formation of tyloses, gels, and callose and changes in the content of cell wall components such as cellulose, hemicellulose, pectin, lignin, and suberin in response to pathogen infestation. When R. solanacearum secrete cell wall degrading enzymes, plants also sense the status of cell wall fragments through the cell wall integrity (CWI) system, which activates deep-seated defense responses. In addition, plants also fight against R. solanacearum infestation by regulating the distribution of metabolic networks to increase the production of resistant metabolites and reduce the production of metabolites that are easily exploited by R. solanacearum. We review the strategies used by plants to induce resistance in response to R. solanacearum infestation. In particular, we highlight the importance of plant-induced physical and chemical defenses as well as cell wall defenses in the fight against R. solanacearum

Genome-Wide Analysis of Sorghum GT47 Family Reveals Functional Divergences of MUR3-Like Genes

Sorghum (Sorghum bicolor) is an important bioenergy crop. Its biomass mainly consists of the cellulosic and non-cellulosic polysaccharides, both which can be converted to biofuels. The biosynthesis of non-cellulosic polysaccharides involves several glycosyltransferases (GT) families including GT47. However, there was no systemic study on GT47 family in sorghum to date. Here, we identified 39 sorghum GT47 family members and showed the functional divergences of MURUS3 (MUR3) homologs. Sorghum GT47 proteins were phylogenetically clustered into four distinct subfamilies. Within each subfamily, gene structure was relatively conserved between the members. Ten gene pairs were identified from the 39 GT47 genes, of which two pairs might be originated from tandem duplication. 25.6% (10/39) of sorghum GT47 genes were homologous to Arabidopsis MUR3, a xyloglucan biosynthesis gene in primary cell walls. SbGT47_2, SbGT47_7, and SbGT47_8, three most homologous genes of MUR3, exhibited different tissue expression patterns and were selected for complementation into Arabidopsis mur3-3. Physiological and cell wall analyses showed that SbGT47_2 and SbGT47_7 may be two functional xyloglucan galactosyltransferases in sorghum. Further studies found that MUR3-like genes are widely present in the seed plants but not in the chlorophytic alga Chlamydomonas reinhardtii. Our results provide novel information for evolutionary analysis and functional dissection of sorghum GT47 family members

Investigation of Water Absorption Behavior of Recycled Aggregates and its Effect on Concrete Strength

The water–cement ratio (w/c) has a significant effect on the strength of recycled concrete. In this study, considering the effects of water/cement ratio, strength, and water content of recycled aggregates, two kinds of pulse sequences of low-field nuclear magnetic resonance (LF-NMR) were applied to investigate the water migration behavior between simulated recycled aggregates (SRA) and water or fresh mortar. Three sets of concrete strength tests were designed and the results were used to verify the findings of LF-NMR imaging tests. The results showed that the depth of water migration in the SRA increases with time: at first the change rate is rapid, then slows down, and eventually tends to remain stable. When the SRA is in contact with fresh mortar with low w/c, no water migration occurs because the hydration of the cement in the mixture consumes a large amount of water, resulting in the inability of water to migrate into the SRA through capillary pressure. For the recycled aggregate concrete with high strength, the addition of extra water will increase the effective w/c and reduce the compressive strength of the concrete

Genome-Wide Identification and Expression Profiling Analysis of the Xyloglucan Endotransglucosylase/Hydrolase Gene Family in Tobacco (Nicotiana tabacum L.)

Xyloglucan endotransglucosylase/hydrolase genes (XTHs) encode enzymes required for the reconstruction and modification of xyloglucan backbones, which will result in changes of cell wall extensibility during growth. A total of 56 NtXTH genes were identified from common tobacco, and 50 cDNA fragments were verified by PCR amplification. The 56 NtXTH genes could be classified into two subfamilies: Group I/II and Group III according to their phylogenetic relationships. The gene structure, chromosomal localization, conserved protein domains prediction, sub-cellular localization of NtXTH proteins and evolutionary relationships among Nicotiana tabacum, Nicotiana sylvestrisis, Nicotiana tomentosiformis, Arabidopsis, and rice were also analyzed. The NtXTHs expression profiles analyzed by the TobEA database and qRT-PCR revealed that NtXTHs display different expression patterns in different tissues. Notably, the expression patterns of 12 NtXTHs responding to environment stresses, including salinity, alkali, heat, chilling, and plant hormones, including IAA and brassinolide, were characterized. All the results would be useful for the function study of NtXTHs during different growth cycles and stresses

Attribution and Risk Assessment of Wind Erosion in the Aral Sea Regions Using Multi-Source Remote Sensing and RWEQ on GEE

The rapid desiccation of the Aral Sea has transformed the region into one of the world’s most severe soil wind-erosion hotspots. Despite growing concern, long-term, high-resolution assessments and driver attribution remain insufficient. This study integrates the Revised Wind Erosion Equation (RWEQ) with multi-source remote sensing data on the Google Earth Engine (GEE) platform to simulate wind erosion dynamics from 1990 to 2020. The residual trend method was used to disentangle the contributions of climate change and human activities, while erosion risk was assessed using the Information Quantity model and Analytic Hierarchy Process (AHP). This study reveals five key findings: (1) wind erosion increased significantly after 2011, peaking in 2015 with an annual growth rate of 2.418 kg/m2. (2) The Aral Sea Basin’s relative contribution to regional erosion declined sharply, indicating a shift in dominant erosion zones to peripheral deserts. (3) Climate change emerged as the primary driver, contributing 70.19% overall, and up to 92.13% in recent years, while human activities showed a peak influence (55.53%) in 2005. (4) Spatial attribution showed climate dominance in desert areas and localized human impact in exposed lakebeds. (5) High-risk erosion zones expanded rapidly into the Kyzylkum Desert after 2010, due to rising wind speeds and vegetation loss. This study provides a robust remote sensing–based framework for wind erosion monitoring and attribution, offering critical insights for erosion mitigation and ecological restoration in arid, climate-sensitive regions

Progress in Optimization of Agrobacterium-Mediated Transformation in Sorghum (Sorghum bicolor)

This review archives the achievements made in the last two decades and presents a brief outline of some significant factors influencing the Agrobacterium-mediated transformation of Sorghum bicolor. Recently, progress in successful transformation has been made for this particular monocot crop through direct DNA delivery method and indirect method via Agrobacterium. However, lower transformation rate still proved to be a bottleneck in genetic modification of sorghum. An efficient Agrobacterium transformation system could be attained by optimizing the preliminary assays, comprising of explant source, growth media, antibiotics, Agrobacterium strains and agro-infection response of callus. The selection of competent strains for genetic transformation is also one of the key factors of consideration. Successful transformation is highly dependent on genome configuration of selected cultivar, where non-tannin genotype proved the best suited. Immature embryos from the field source have higher inherent adaptation chances than that of the greenhouse source. A higher concentration of Agrobacterium may damage the explant source. Utilization of anti-necrotic treatments and optimized tissue culture timeframe are the adequate strategies to lower down the effect of phenolic compounds. Appropriate selection of culture media vessels at different stages of tissue culture may also assist in a constructive manner. In conclusion, some aspects such as culture environment with medium composition, explant sources, and genotypes play an indispensable role in successful Agrobacterium-mediated sorghum transformation system