No abstract

Nitrogen loss after urea application and the low nitrogen utilization rate of plants are major issues in fertilizer application. We therefore adopted a combination of urea and 3,4-dimethylpyrazole phosphate (DMPP) applications in order to investigate the response of DMPP in ‘sweet sapphire’ (V. vinifera L.) grape seedlings growth. Three combinations of DMPP and urea were tested to screen suitable DMPP application concentrations for grape seedlings’ growth. Transcriptome differential expression analysis was adopted to elucidate the regulation mechanism of DMPP. The results showed that the application of DMPP with urea significantly increased grape seedlings’ root dry weight, as well as the above-ground dry weight. The application of DMPP with urea significantly improved the total root length, surface area, volume, and root vigor. The application of urea nitrogen content with 1% of DMPP (T2) showed optimum effects. The application of DMPP can also significantly increase the net photosynthetic rate, photosynthetic pigments, and fluorescence intensity of grape leaves. Furthermore, the transcriptome differential expression analysis under T2 treatment revealed that members of the Nar (7) and NRT (12) gene families were up-regulated, which promotes nitrogen uptake and metabolism. Moreover, the LHC (11), Psa (7), Pet (4), and Psb (5) genes were up-regulated, which promotes photosynthesis.

Vitis vinifera × Vitis labrusca ‘Shenhua’ is a tetraploid grape, a Franco-american species. This study first published the complete chloroplast genome of Vitis vinifera × Vitis labrusca ‘Shenhua’ was assembled. The chloroplast genome is 160928 bp in length, including a large single copy region (89,148 bp), a small single-copy region (19,072 bp) and a pair of inverted repeats of 26,354 bp. The chloroplast genome encodes 133 genes, comprising 88 CDSs, 37 tRNA genes and 8 rRNA genes. The phylogenetic tree demonstrated that Vitis vinifera × Vitis labrusca ‘Shenhua’ is different from the other 16 varieties.