Ten new lycodine-type alkaloids, named casuarinines A-J (1-10), along with eight known analogues (11-18), were isolated from the whole plant of Lycopodiastrum casuarinoides . The new structures were established by spectroscopic methods and chemical transformations. Casuarinines A-D (1-4) and J (10) are common lycodine alkaloids possessing four connected six-membered rings, while tricyclic casuarinines E-H (5-8) are the piperidine ring cleavage products. In particular, casuarinine I (9) has an unprecedented five-membered tetrahydropyrrole ring instead of the piperidine ring. A plausible biosynthetic pathway to 9 is proposed. Among the compounds reported, casuarinine H (8) exhibited significant neuroprotective effect against hydrogen peroxide (H₂O₂)-induced neuronal cell damage in human neuroblastoma SH-SY5Y cells, while casuarinines C (3) and I (9) showed moderate inhibitory activity against acetylcholinesterase (AChE).

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Maximum tiller number and productive tiller number are important traits for wheat grain yield, but research involving the temporal expression of tiller number at different quantitative trait loci (QTL) levels is limited. In the present study, a population set of 371 recombined inbred lines derived from a cross between Chuan-Nong18 and T1208 was used to construct a high-density genetic map using a Wheat55K SNP Array and to perform dynamic QTL analysis of the tiller number at four growth stages. A high-density genetic map containing 11,583 SNP markers and 59 SSR markers that spanned 4,513.95 cM and was distributed across 21 wheat chromosomes was constructed. A total of 28 single environmental QTL were identified in the recombined inbred lines population, and among these, seven QTL were stable and used for multi-environmental and dynamic analysis. These QTL were mapped to chromosomes 2D, 4A, 4D, 5A, 5D, and 7D, respectively. Each QTL explained 1.63–21.22% of the observed phenotypic variation, with an additive effect from -20.51 to 11.59. Dynamic analysis showed that cqTN-2D.2 can be detected at four growth stages of tillering, explaining 4.92–17.16% of the observed phenotypic variations and spanning 13.71 Mb (AX-109283238-AX-110544009: 82189047-95895626) according to the physical location of the flanking markers. The effects of the stable QTL were validated in the recombined inbred lines population, and the beneficial alleles could be utilized in future marker-assisted selection. Several candidate genes for MTN and PTN were predicted. The results provide a better understanding of the QTL selectively expressing the control of tiller number and will facilitate future map-based cloning. 9.17% SNP markers showed best hits to the Chinese Spring contigs. It was indicated that Wheat55K Array was efficient and valid to construct a high-density wheat genetic map.

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Five new preussomerin analogues, ymf 1029A (1), B (2), C (3), D (4), and E (5), were isolated from the liquid cultures of an unidentified freshwater fungus YMF 1.01029, along with four known compounds, preussomerin C (6), preussomerin D (7), (4RS)-4,8-dihydroxy-3,4-dihydronaphthalen-1(2H)-one (8), and 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one (9). The structures of new metabolites were determined by analysis of NMR and MS data and by analogy with the data for the known bis-spirobisnaphthalene preussomerins. In vitro immersion experiments showed that these metabolites displayed weak nematicidal activity against Bursaphelenchus xylophilus, while compound 7 was the most potent. This is the first report of these compounds, which antagonize the Bursaphelenchus xylophilus nematode.