Blackberry and raspberry have high nutritional, health value, and are popular with consumers for their unique flavors. To explore the relationships between nutrient accumulation, antioxidant substance contents in blackberry and raspberry fruits, and fruit growth and development, seven Rubus cultivars were selected, and contents of the main active substance were determined. “Clode Summit” had the highest soluble sugar and fructose contents, “Chester”—the highest total phenol content, and “Bristol’—the highest anthocyanin content. Generally, the contents of flavonoids and total phenols showed a downward trend with the development of fruit in seven Rubus cultivars, and the content of anthocyanins increased rapidly in the later stage of development. Pearson correlation analysis showed extremely significant correlation between antioxidant activity and the contents of vitamin E, total phenols, and flavonoids. Flavonoids were extremely significantly positively correlated with the content of total phenols, and the contents of flavonoids and anthocyanins in various cultivars were highly negatively correlated. Considering the different nutritional ingredients and active antioxidant substance contents, “Clode Summit”, “Bristol”, and “Chester” are recommended for raw consumption, processing, and medicinal purposes, respectively. These results provide a reference for comparing the main active substance contents in different Rubus cultivars and their changes across fruit development stages.

Background: Transcription factors (TFs) play important roles in plants. Among the major TFs, GATA plays a crucial role in plant development, growth, and stress responses. However, there have been few studies on the GATA gene family in foxtail millet (Setaria italica). The release of the foxtail millet reference genome presents an opportunity for the genome-wide characterization of these GATA genes. Results: In this study, we identified 28 GATA genes in foxtail millet distributed on seven chromosomes. According to the classification method of GATA members in Arabidopsis, SiGATA was divided into four subfamilies, namely subfamilies I, II, III, and IV. Structural analysis of the SiGATA genes showed that subfamily III had more introns than other subfamilies, and a large number of cis-acting elements were abundant in the promoter region of the SiGATA genes. Three tandem duplications and five segmental duplications were found among SiGATA genes. Tissue-specific results showed that the SiGATA genes were mainly expressed in foxtail millet leaves, followed by peels and seeds. Many genes were significantly induced under the eight abiotic stresses, such as SiGATA10, SiGATA16, SiGATA18, and SiGATA25, which deserve further attention. Conclusions: Collectively, these findings will be helpful for further in-depth studies of the biological function of SiGATA, and will provide a reference for the future molecular breeding of foxtail millet.

• The FT1 shading treatment yielded the largest values for blueberry single fruit weight. • The highest total phenol, anthocyanin and vitamin C contents under the FT1 shading treatment. • 470 known metabolites were obtained from blueberry fruits. • This study provides scientific basis for improving the quality of blueberry fruit.

Blackberries are an emerging third-generation fruit that are popular in Europe, and specific nitrogen (N) supply is an important factor affecting their growth and development. To study the optimal N fertilizer for blackberry seedlings, no N (CK), nitrate (NO₃⁻)–N, ammonium (NH₄⁺)–N and urea were applied to one-year-old ‘Ningzhi 4’ blackberry plants at a key growth period (from May to August) to explore the effects of different N forms on the physiological characteristics. Correlation and principal component analysis were used to determine the relationships between various indexes. Ammonium (NH₄⁺) or urea-fed plants had a better growth state, showed a greater plant height, biomass, SPAD values and enhanced antioxidant enzyme activities and photosynthesis. In addition, NH₄⁺ was beneficial to the accumulation of sugars and amino acids in leaves and roots, and promoted the transport of auxin and cytokinin to leaves. NO₃⁻ significantly inhibited root growth and increased the contents of active oxygen, malondialdehyde and antioxidants in roots. Correlation and principal component analysis showed that growth and dry matter accumulation were closely related to the antioxidant system, photosynthetic characteristics, amino acids and hormone content. Our study provides a new idea for N regulation mechanism of blackberry and proposes a scientific fertilization strategy.

Blueberry belongs to the genus Vaccinium L. in the Ericaceae and is an economically important shrub that produces small berries that are rich in nutrients. There were differences in the appearance of blueberry leaves under different shade treatments. To explore the differences in metabolites in blueberry leaves under different shading treatments, nontargeted liquid chromatography–mass spectrometry (LC–MS) metabonomic analysis was performed. Different shade intensities resulted in significant differences in the contents of metabolites. A total of 6879 known metabolites were detected, including 750 significantly differentially expressed metabolites, including mainly lipids and lipid-like molecules and phenylpropanoid and polyketide superclass members. Based on a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, the flavone and flavonol biosynthesis pathways were the most significantly enriched. The results of this study provide a reference and scientific basis for the establishment of a high-quality and high-yield shaded blueberry cultivation system.

To study the optimal form of nitrogen (N) application and to determine the best harvest date for blackberries, different N fertilizers were applied during the critical growth period of blackberry plants. The results showed that NH₄⁺–N significantly improved the appearance of blackberry fruits, including their size, firmness, and color, and promoted the accumulation of soluble solids, sugars, anthocyanin, ellagic acid, and vitamin C (VC), while fruit treated with NO₃⁻–N accumulated more flavonoids and organic acids and had improved antioxidant capacity. In addition, the fruit size, firmness, and color brightness decreased with the harvest period. While the contents of sugars, anthocyanin, ellagic acid, flavonoids, and VC were higher in the early harvests and then decreased as the season progressed, the total antioxidant capacity and DPPH radical scavenging capacity increased. In all, application of NH₄⁺–N is recommended, as it is more beneficial to fruit appearance, taste, and nutritional quality. Harvests in the early stage help to obtain a good fruit appearance, while harvests in the middle and later stages are more beneficial to fruit taste and quality. This study may help growers to determine the best fertilization scheme for blackberries and choose the appropriate harvest time according to their needs.