EjGASA6 promotes flowering and root elongation by enhancing gibberellin biosynthesis

The Gibberellic Acid-stimulated Arabidopsis(GASA)gene family is involved in the regulation of gene expression and plant growth,development,and stress responses.To investigate the function of loquat GASA genes in the growth and developmental regulation of plants,a loquat EjGASA6 gene homologous to Arabidopsis AtGASA6 was cloned.EjGASA6 expression was induced by gibberellin,and ectopic transgenic plants containing this gene exhibited earlier bloom and longer primary roots since these phenotypic characteristics are related to higher gibberellin content.Transcriptome analysis and qRT-PCR results showed that the expression levels of GA3ox1 and GA20ox1,which encode key enzymes in gibberellin biosynthesis,were significantly increased.Furthermore,we confirmed that EjGASA6 could promote the expression of GA20ox1 via the luciferase reporter system.Overall,our results suggest that EjGASA6 promotes blooming and main-root elongation by positively regulating gibberellin biosynthesis.These findings broaden our understanding of the role of GASAs in plant development and growth,and lay the groundwork for future research into the functions of EjGASA6 in regulating loquat growth and development.

Genome assembly of wild loquat (Eriobotrya japonica) and resequencing provide new insights into the genomic evolution and fruit domestication in loquat

Wild loquats(Eriobotrya japonica Lindl.)provide remarkable genetic resources for studying domestication and breeding improved varieties.Herein,we generate the first high-quality chromosome-level genome assembly of wild loquat,with 45791 predicted proteincoding genes.Analysis of comparative genomics indicated that loquat shares a common ancestor with apple and pear,and a recent whole-genome duplication event occurred in loquat prior to its divergence.Genome resequencing showed that the loquat germplasms can be distinctly classified into wild and cultivated groups,and the commercial cultivars have experienced allelic admixture.Compared with cultivated loquats,the wild loquat genome showed very few selected genomic regions and had higher levels of genetic diversity.However,whole-genome scans of selective sweeps were mainly related to fruit quality,size,and f lesh color during the domestication process.Large-scale transcriptome and metabolome analyses were further performed to identify differentially expressed genes(DEGs)and differentially accumulated metabolites(DAMs)in wild and cultivated loquats at various fruit development stages.Unlike those in wild loquat,the key DEGs and DAMs involved in carbohydrate metabolism,plant hormone signal transduction,f lavonoid biosynthesis,and carotenoid biosynthesis were significantly regulated in cultivated loquats during fruit development.These high-quality reference genome,resequencing,and large-scale transcriptome/metabolome data provide valuable resources for elucidating fruit domestication and molecular breeding in loquat.

Effects of Different Fertilization Treatments on Soil, Leaf Nutrient and Fruit Quality of Citrus grandis var. longanyou

The five-year-old “Longanyou” trees were used as the experimental material to study the effects of different fertilization treatments. The nutrient contents in soil and leaves, fruit yield and quality were determined, and then the correlations were analyzed. The results showed that: 1) The soil nutrient contents of 0 - 20 cm depth were more than the 20 - 40 cm, and the trends of nutrient contents of the 0 - 20 cm soil layers were as follows: treatment 2 (T2) > treatment 3 (T3) > treatment 4 (T4) > treatment 1(T1) > control (CK). However, the 20 - 40 cm depth had not significant difference between different treatments, but T2, T4 and T3 were higher than T1 and CK. It indicated that the soil effective nutrient content increased in T2 and T3. 2) Compared with the control, the content of K and B elements was improved obviously in leaves with the increase of organic manure application. The contents of P (1.60 g·kg-1), B (26.00 mg·kg-1) and Mg (1.18 g·kg-1) were the highest, and other nutrients contents were also higher, indicating that T2 could effectively improve the leaves’ nutrient contents. 3) The fruit yield per plant was the highest in T2 (95.40 kg plant-1), and the single fruit weight, total sugar, sugar and acid ratio, vitamin C were also the highest, but titratable acid was lower. It indicated that T2 effectively improved fruit yield and quality. 4) There were positive correlations between multiple factors of soil nutrients and the quality index, such as fruit peel thickness, total sugar, solid acid ratio, sugar and acid ratio, Vc content and single yield etc. There was significant correlation between K, B, Zn, Fe contents and fruit yield and quality index, and the contents of B, Zn and Fe in leaves were significantly correlated with soil nutrient, indicating that the contents of K, B, Zn, Fe in soil and leaf were closely related to fruit yield and quality. In sum, the T2 was the best fertilization scheme for orchard management practice of “Longanyou”.

Genetic Diversity Analysis of Balsam Pear(Momordica charantia L.) by ISSR Marker

[Objective] The aim was to explore the relationship between the classification and regional distribution of balsam pear. [Method] In the research, 30 varieties of balsam pear were analyzed by ISSR marker. [Result] The research showed that172 bands were amplified by 18 primers, in which, 132 bands were polymorphism and the polymorphic proportion was 76.7%. All of the samples can be divided into four categories by UPGMA analysis. [Conclusion] The results indicated that the classification of balsam pear is similar as varieties' regional distribution, which will be useful for genetic relationships analysis and parents selection in hybridization breeding.

Global Lysine Acetylome Analysis of Flower Bud Development in Catalpa bungei

Lysine acetylation,a reversible and dynamic post-translational modification,plays pivotal roles in regulating many biological processes in plants.However,the information of lysine acetylation during flower development of woody angiosperm remains unclear.Herein,we identified a total of 667 lysine acetylation sites in 467 proteins in flower buds of Catalpa Bungei.The acetylated proteins were mainly involved in the pathways of carbon metabolism,glycometabolism and oxidative phosphorylation.Using functional enrichment analysis,61 and 13 acetylated proteins were involved in the glycometabolism and oxidative phosphorylation pathways,respectively.This suggests that lysine acetylated proteins play critical roles in the energy metabolism pathways.Accordingly,the protein–protein interactions were also highly enriched in the carbon metabolic pathway.Integrative analysis of lysine acetylome and transcriptome showed that transcript level changes of seven key lysine-acetylated proteins/genes involved in energy metabolism were significant different during floral transition.Importantly,compared with the normal flowering variety,the expression levels of phosphoribulokinase,phosphoenolpyruvate carboxykinase,ATP synthase and pyruvate dehydrogenase complex genes were significantly up-regulated at the stages of vegetative and transition buds during early flowering of C.bungei.These data represent the first lysine acetylome in the C.bungei flowers,and can serve as an essential basis for exploring the function of lysine acetylated proteins in the flower bud development of plants.

Segregation Correlation of SSR Markers and Flower Traits in Aneuploid Tobacco

Few reports have been seen on the segregation of polyploids and on the relationship between the segregation of SSR loci and that of the morphological traits in polyploid progeny. This paper attempted to gain an insight into the segregation of the hexaploid tobacco progeny and to understand the correlation of the segregation of SSR loci with that of the flower morphological traits. The segregation was evaluated with both SSR markers and morphological traits of the flowers. Twenty pairs of SSR primers were screened and a total of 42 SSR loci were identified. Chi-square analysis showed that the segregation ratio of the SSR loci in the aneuploid progeny was between 1:1 and 2:1. Six morphological traits of flowers, including the lengths of the flower and the calyx, the widths of the calyx, the corolla tube and the corolla, and the coloring of the flower, from 180 progeny and 2 progenitor plants, were determined and Chi-square analyzed. All traits were in consistent also with a segregation ratio of 1:1 to 2:1 except the width of the calyx.