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With the concept of "mosaic warfare," a novel combat style that involves constructing "kill webs" with unmanned aerial vehicle (UAV) swarms has emerged. However, little research has focused on this specific task scenario, particularly concerning the self-organization and adaptive collaboration of heterogeneous combat units in dynamic contested environments. Considering the scales and highly dynamic natures of such swarms, an adaptive communication network mechanism is developed based on the Molloy-Reed criterion. In contrast with common offline/noncombat task scenarios, the self-organization process is refined through agent-based modeling, and a combat effectiveness evaluation is introduced to provide enhanced task execution incentives. The proposed dynamic consensus-based coalition algorithm (DCBCA) addresses UAV intelligence defects such as "confusion," "forgetfulness," and "recklessness" during the dynamic target selection process, enabling effective bottom-up kill webs construction. Extensive simulation results demonstrate that the algorithmic system outlined in this paper can support the efficient and resilient operations of large-scale heterogeneous UAV swarms. The DCBCA outperforms the dynamically improved consensus-based grouping algorithm (CBGA) and the consensus-based timetable algorithm (CBTA) in terms of performance and convergence speed. [ABSTRACT FROM AUTHOR]

Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most destructive diseases that pose a great threat to wheat production. Wheat landraces represent a rich source of powdery mildew resistance. Here, we report the map-based cloning of powdery mildew resistance gene Pm24 from Chinese wheat landrace Hulutou. It encodes a tandem kinase protein (TKP) with putative kinase-pseudokinase domains, designated WHEAT TANDEM KINASE 3 (WTK3). The resistance function of Pm24 was validated by transgenic assay, independent mutants, and allelic association analyses. Haplotype analysis revealed that a rare 6-bp natural deletion of lysine-glycine codons, endemic to wheat landraces of Shaanxi Province, China, in the kinase I domain (Kin I) of WTK3 is critical for the resistance function. Transgenic assay of WTK3 chimeric variants revealed that only the specific two amino acid deletion, rather than any of the single or more amino acid deletions, in the Kin I of WTK3 is responsible for gaining the resistance function of WTK3 against the Bgt fungus. Powdery mildew is a major threat to world wheat yields. Here the authors describe the map-based cloning of Pm24, a gain-of-function powdery mildew resistance allele that encodes a tandem kinase-pseudokinase protein with a deletion in a kinase domain that is endemic to certain wheat landraces. [ABSTRACT FROM AUTHOR]

Verticillium dahliae causes wilt diseases and early senescence in numerous plants, including agricultural crops such as cotton. In this study, we studied two closely related V. dahliae strains, and found that V991w showed significantly reduced virulence on cotton than V991b. Comprehensive transcriptome analysis revealed various differentially expressed genes between the two strains, with more genes repressed in V991w. The downregulated genes in V991w were involved in production of hydrophobins, melanin, predicted aflatoxin, and membrane proteins, most of which are related to pathogenesis and multidrug resistance. Consistently, melanin production in V991w in vitro was compromised. We next obtained genomic variations between the two strains, demonstrating that transcription factor genes containing fungi specific transcription factor domain and fungal Zn2-Cys6 binuclear cluster domain were enriched in V991w, which might be related to pathogenicity-related genes downregulation. Thus, this study supports a model in which some virulence factors involved in V. dahliae pathogenicity were pre-expressed during in vitro growth before host interaction. [ABSTRACT FROM AUTHOR]

In this investigation of the efficacy of the natural product physcion for the control of gray mold of tomato in the field and possible modes of action, physcion was significantly less effective in in vitro antifungal tests than synthetic fungicides pyrimethanil and boscalid. However, in greenhouse tests, physcion dramatically reduced the severity of gray mold on tomato plants. We further found elevated activity of several enzymes associated with the synthesis of phenolic compounds and plant defense reactions, including phenylalanine ammonia-lyase, peroxidase, and polyphenol oxidase. Physcion also significantly increased plant growth, indicating that it can also act as a growth promoter in tomato. The results from two consecutive years of field trials revealed that the application of physcion at a rate of 9 g a.i./ha reduced disease incidence between 63.44 and 69.79%, comparable to the fungicide pyrimethanil. Together, these results indicate that although physcion had little direct effect on the growth of B. cinerea, it increased tomato performance by stimulating an endogenous plant defense response and acting as a growth promoter. The study therefore provides strong evidence that physcion provides an alternative treatment for the management of gray mold in organic and low input tomato production and in traditional integrated pest management programs. [ABSTRACT FROM AUTHOR]

The wheat Pm3 resistance gene against the powdery mildew pathogen occurs as an allelic series encoding functionally different immune receptors which induce resistance upon recognition of isolate-specific avirulence (AVR) effectors from the pathogen. Here, we describe the identification of five effector proteins from the mildew pathogens of wheat, rye, and the wild grass Dactylis glomerata, specifically recognized by the PM3B, PM3C and PM3D receptors. Together with the earlier identified AVRPM3A2/F2, the recognized AVRs of PM3B/C, (AVRPM3B2/C2), and PM3D (AVRPM3D3) belong to a large group of proteins with low sequence homology but predicted structural similarities. AvrPm3b2/c2 and AvrPm3d3 are conserved in all tested isolates of wheat and rye mildew, and non-host infection assays demonstrate that Pm3b, Pm3c, and Pm3d are also restricting the growth of rye mildew on wheat. Furthermore, divergent AVR homologues from non-adapted rye and Dactylis mildews are recognized by PM3B, PM3C, or PM3D, demonstrating their involvement in host specificity. The wheat Pm3 immune receptors confer resistance against powdery mildew by recognizing isolate-specific avirulence (AVR) effectors of the pathogen. Here, the authors identify and characterize two new AVR genes and demonstrate that Pm3 receptors are determinants of host-specificity for grass mildews. [ABSTRACT FROM AUTHOR]