A new ligand {2-(5-nitro-furan-2-yl)-1H-1,3,7,8-tetraaza-cyclopenta[l]-phenanthrene} (nftp) and its Ru(II) complexes [Ru(phen)(2)(nftp)](2+) (1) (phen = 1,10-phenanthroline) and [Ru(bpy)(2)(nftp)](2+) (2) (bpy = 2,2'-bipyridine) were synthesized and characterized. The binding properties of the two complexes to calf thymus-DNA (CT-DNA) were investigated by different spectrophotometric methods and viscosity measurements together with equilibrium dialysis and circular dichroism spectroscopy. The results suggest that both complexes bind to DNA through intercalation and enantioselectively interact with CT-DNA. However, complex 1 is a better candidate as an enantioselective binder to CT-DNA than complex 2. Although no emission is generally observed in water or organic solvents for Ru(II) polypyridyl complexes with a nitro group, complexes 1 and 2 can emit luminescence in both media. When irradiated at 365 nm, complex 1 cleaves DNA more effectively than complex 2.

Spikelet number and grain number per spike are two crucial and correlated traits for grain yield in wheat. Photoperiod-1 (Ppd-1) is a key regulator of inflorescence architecture and spikelet formation in wheat. In this study, near-isogenic lines derived from the cross of a synthetic hexaploid wheat and commercial cultivars generated by double top-cross and two-phase selection were evaluated for the number of days to heading and other agronomic traits. The results showed that heading time segregation was conferred by a single incomplete dominant gene PPD-D1, and the 2 kb insertion in the promoter region was responsible for the delay in heading. Meanwhile, slightly delayed heading plants and later heading plants obviously have advantages in grain number and spikelet number of the main spike compared with early heading plants. Utilization of PPD-D1 photoperiod sensitivity phenotype as a potential means to increase wheat yield potential.

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