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Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) is able to infect many economically important crops and thus causes substantial losses in the global agricultural economy. Pst DC3000 can be divided into virulent lines and avirulent lines. For instance, the pathogen effector avrRPM1 of avirulent line Pst-avrRpm1 (Pst DC3000 avrRpm1) can be recognized and detoxified by the plant. To further compare the pathogenicity mechanisms of virulent and avirulent Pst DC3000, a comprehensive analysis of the acetylome and succinylome in Arabidopsis thaliana was conducted following infection with virulent line Pst DC3000 and avirulent line Pst-avrRpm1. In this study, a total of 1625 acetylated proteins encompassing 3423 distinct acetylation sites were successfully identified. Additionally, 229 succinylated proteins with 527 unique succinylation sites were detected. A comparison of these modification profiles between plants infected with Pst DC3000 and Pst-avrRpm1 revealed significant differences. Specifically, modification sites demonstrated inconsistencies, with a variance of up to 10% compared to the control group. Moreover, lysine acetylation (Kac) and lysine succinylation (Ksu) displayed distinct preferences in their modification patterns. Lysine acetylation is observed to exhibit a tendency towards up-regulation in Arabidopsis infected with Pst-avrRpm1. Conversely, the disparity in the number of Ksu up-regulated and down-regulated sites was not as pronounced. Motif enrichment analysis disclosed that acetylation modification sequences are relatively conserved, and regions rich in polar acidic/basic and non-polar hydrophobic amino acids are hotspots for acetylation modifications. Functional enrichment analysis indicated that the differentially modified proteins are primarily enriched in the photosynthesis pathway, particularly in relation to light-capturing proteins. In conclusion, this study provides an insightful profile of the lysine acetylome and succinylome in A. thaliana infected with virulent and avirulent lines of Pst DC3000. Our findings revealed the potential impact of these post-translational modifications (PTMs) on the physiological functions of the host plant during pathogen infection. This study offers valuable insights into the complex interactions between plant pathogens and their hosts, laying the groundwork for future research on disease resistance and pathogenesis mechanisms. [ABSTRACT FROM AUTHOR]

Salt–alkali stress threatens the resilience to variable environments and thus the grain yield of rice. However, how rice responds to salt–alkali stress at the molecular level is poorly understood. Here, we report isolation of a novel salt–alkali-tolerant rice (SATR) by screening more than 700 germplasm accessions. Using 93-11, a widely grown cultivar, as a control, we characterized SATR in response to strong salt–alkali stress (SSAS). SATR exhibited SSAS tolerance higher than 93-11, as indicated by a higher survival rate, associated with higher peroxidase activity and total soluble sugar content but lower malonaldehyde accumulation. A transcriptome study showed that cell wall biogenesis-related pathways were most significantly enriched in SATR relative to 93-11 upon SSAS. Furthermore, higher induction of gene expression in the cell wall matrix polysaccharide biosynthesis pathway, coupled with higher accumulations of hemicellulose and pectin as well as measurable physio-biochemical adaptive responses, may explain the strong SSAS tolerance in SATR. We mapped SSAS tolerance to five genomic regions in which 35 genes were candidates potentially governing SSAS tolerance. The 1,4-β-D-xylan synthase gene OsCSLD4 in hemicellulose biosynthesis pathway was investigated in details. The OsCSLD4 function-disrupted mutant displayed reduced SSAS tolerance, biomass and grain yield, whereas the OsCSLD4 overexpression lines exhibited increased SSAS tolerance. Collectively, this study not only reveals the potential role of cell wall matrix polysaccharides in mediating SSAS tolerance, but also highlights applicable value of OsCSLD4 and the large-scale screening system in developing SSAS-tolerant rice. [ABSTRACT FROM AUTHOR]

Precision agriculture technology can transform farming related data into useful information, which may lead to more efficient usage of agricultural resources and increase sustainability. This paper compares precision agriculture technology with traditional practices in scheduling fungicide application so as to manage late blight disease in tomato production. The following three fungicide scheduling strategies were evaluated: a calendar-based strategy, the BlightPro Decision Support System based strategy (DSS-based strategy), and a strategy that does not involve fungicide application. The data from field trials and computer simulation experiments were used to construct distributions of the net return per acre for the calendar-based and the DSS-based strategies. These distributions were then compared using three standard approaches to ranking risky alternatives, namely: stochastic dominance, stochastic dominance with respect to a function, and stochastic efficiency with respect to a function. Assuming no yield differences between the calendar-based and the DSS-based strategies, the calendar-based strategy was preferred for highly late blight susceptible cultivars, and the DSS-based strategy was preferred for moderately susceptible and moderately resistant cultivars. Assuming no yield differences, the value of the BlightPro Decision Support System ranged from −$28 to $48 per acre. With the yield improvement for the DSS-based strategy included, the DSS-based strategy was preferred for the cultivars in all of the disease-resistance categories with the value ranging from $496 to $1714 per acre. [ABSTRACT FROM AUTHOR]