Publications by authors named "Jin-fang Tan"

Introduction: The juvenile hormone (JH) and 20-hydroxyecdysone (20E) are the central regulating hormones of insect development. The timing of their secretion usually leads to developmental transitions.

Methods: The developmental transitions were evaluated via the starvation treatment and the expressions of two key metamorphosis inducing factor in .

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Background: Holometabolan pupal-specifier broad-complex (BR-C) and adult specifier ecdysone-induced protein 93F (E93) are essential for metamorphosis; however, their interaction and effects on programmed cell death and cell differentiation during pupation remain unclear.

Results: Here, multiple single-guide RNA (sgRNA)-mediated mosaic knockout of BR-C induced a deformed larva/pupa intermediate phenotype in Spodoptera frugiperda. Quantitative real-time polymerase chain reaction (qPCR) analysis showed that the adult specifier E93 was prematurely expressed in the BR-C mutants during the penultimate and last instar larval stages.

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Plants synthesise a vast array of volatile organic compounds (VOCs), which serve as chemical defence and communication agents in their interactions with insect herbivores. Although nitrogen (N) is a critical resource in the production of plant metabolites, its regulatory effects on defensive VOCs remain largely unknown. Here, we investigated the effect of N content in tomato (Solanum lycopersicum) on the tobacco cutworm (Spodoptera litura), a notorious agricultural pest, using biochemical and molecular experiments in combination with insect behavioural and performance analyses.

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Azadirachtin has been used to control agricultural pests for a long time; however, the molecular mechanism of azadirachtin on lepidopterans is still not clear. In this study, the fourth instar larvae of fall armyworm were fed with azadirachtin, and then the ecdysis was blocked in the fourth instar larval stage (L4). The prothoracic glands (PGs) of the treated larvae were dissected for RNA sequencing to determine the effect of azadirachtin on ecdysis inhibition.

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Root hair development is crucial for phosphate absorption, but how phosphorus deficiency affects root hair initiation and elongation remains unclear. We demonstrated the roles of auxin efflux carrier PIN-FORMED2 (PIN2) and phospholipase D (PLD)-derived phosphatidic acid (PA), a key signaling molecule, in promoting root hair development in Arabidopsis thaliana under a low phosphate (LP) condition. Root hair elongation under LP conditions was greatly suppressed in pin2 mutant or under treatment with a PLDζ2-specific inhibitor, revealing that PIN2 and polar auxin transport and PLDζ2-PA are crucial in LP responses.

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The characteristics of adsorption and desorption of DNA by Red soil colloid, Latosol colloid, Chao colloid and Cinnamon colloid at different pH values were studied using a batch method. It showed that there was an increase of solution pH after adsorption of DNA by the four soil colloids in both NaCl and KCl electrolyte systems. The increasing ranges of pH values were in order of Red soil colloid > Latosol colloid > Chao colloid > Cinnamon colloid, and NaCl electrolyte system > KCl electrolyte system.

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Objective: To study the absorption, translocation and accumulation of N, P and K on Achyranthes bidentata.

Method: The contents of N, P and K were determined by mean of sulfuric acid-hydrogen peroxide assimilating method, vanadium-ammonium molybdate colorimetric method and flame photometric method, respectively.

Result: The contents of N, P and K in the plant were decreasing during the growth period.

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