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Background: Fructans are water-soluble carbohydrates that accumulate in wheat and are thought to contribute to a pool of stored carbon reserves used in grain filling and tolerance to abiotic stress. Results: In this study, transgenic wheat plants were engineered to overexpress a fusion of two fructan biosynthesis pathway genes, wheat sucrose: sucrose 1-fructosyltransferase (Ta1SST) and wheat sucrose: fructan 6-fructosyltransferase (Ta6SFT), regulated by a wheat ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (TaRbcS) gene promoter. We have shown that T4 generation transgene-homozygous single-copy events accumulated more fructan polymers in leaf, stem and grain when compared in the same tissues from transgene null lines. Under water-deficit (WD) conditions, transgenic wheat plants showed an increased accumulation of fructan polymers with a high degree of polymerisation (DP) when compared to non-transgenic plants. In wheat grain of a transgenic event, increased deposition of particular fructan polymers such as, DP4 was observed. Conclusions: This study demonstrated that the tissue-regulated expression of a gene fusion between Ta1SST and Ta6SFT resulted in modified fructan accumulation in transgenic wheat plants and was influenced by water-deficit stress conditions. [ABSTRACT FROM AUTHOR]

Background: The diacylhydrazine derivatives have attracted considerable attention in recently years due to their simple structure, low toxicity, and high insecticidal selectivity. As well as 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole is an important scaffold in many insecticidal molecules. In an effort to discover new molecules with good insecticidal activity, a series of diacylhydrazine derivatives containing a 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole scaffold was synthesized and bio-assayed., Results: Bioassays demonstrated that some of the title compounds exhibited favorable insecticidal activities against Helicoverpa armigera and Plutella xylostella. The insecticidal activity of compounds 10g, 10h, and 10w against H. armigera were 70.8, 87.5, and 79.2%, respectively. Compounds 10c, 10e, 10g, 10h, 10i, 10j and 10w showed good larvicidal activity against P. xylostella. In particular, the LC 50 values of compounds 10g, 10h, and 10w were 27.49, 23.67, and 28.90 mg L -1 , respectively., Conclusions: A series of diacylhydrazine derivatives containing a 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole scaffold was synthesized and bio-assayed. The results of insecticidal tests revealed that the synthesized diacylhydrazine derivatives possessed weak to good insecticidal activities against H. armigera and P. xylostella. Compounds 10g, 10h, and 10x showed much higher insecticidal activity than tebufenozide, and exhibited considerable prospects for further optimization. Primary structure-activity relationship revealed that phenyl, 4-fluoro phenyl and four fluorophenyl showed positive influence on their insecticidal activities, and introduction of a heterocyclic ring (pyridine and pyrazole) showed negative impacts on their insecticidal effects.