Morphological, physiological and biochemical changes in Magnolia zenii Cheng seed during development

Abstract

An understanding of the seed dynamics of endangered plant species, such as Magnolia zenii Cheng, is important for successful conservation. This study examined the morphological, physiological and biochemical changes that occur in M. zenii Cheng during seed development to determine the appropriate harvest stage. The appearance of the seeds was influenced by the physiological and biochemical changes occurring during the developmental period, during which the colour of the fruits changed from green to red, while that of the seed changed from light brown to dark brown. There was a significant decrease in the seed moisture content from 90 to 120 days after flowering (DAF); however, there was no significant change from 135 to 165 DAF. The seeds from 135 DAF onwards showed developed cotyledonary embryos. The seed viability exceeded 95% from 135 DAF onwards; however, the germination percentage was 0, hypothesising that the seeds of M. zenii Cheng might exhibit physiological dormancy under certain conditions of this experiment. There was a significant increase in the fat, soluble sugar and soluble starch content of the seeds while approaching maturity.There were significant changes in malate dehydrogenase (MDH), glucose-6-phosphate dehydrogenase (G-6-PDH), 6-phosphogluconate dehydrogenase (6-PGDH) and β-amylase activities in the seeds during the developmental period. At 135-165 DAF, the MDH activity remained stable, whereas that of 6-PGDH reached its maximum, indicating that the seeds underwent vigorous metabolism. The findings of this study provide a theoretical basis for researching seed dormancy and seed harvest time. | INTRODUCTIONMagnolia zenii Cheng is a deciduous tree belonging to the subgenus Magnolia and family Magnoliaceae and is endemic to China. The existing natural communities are distributed on the northern slope of Baohua Mountain in Jurong City, Jiangsu province (Xu et al., 2001). M. zenii Cheng is a precious ornamental garden tree, and its flowers and fruits can be used as medicine. Recent studies have shown that the seed extract of M. zenii Cheng has antiinflammatory and anti-tumour effects (Song et al., 2012(Song et al., , 2013Song & Li, 2012a, 2012b. However, owing to the limited environment range of M. zenii Cheng and interspecific competition, the population of adult and seedlings of M. zenii Cheng in the wild is

Aging-Induced Reduction in Safflower Seed Germination via Impaired Energy Metabolism and Genetic Integrity Is Partially Restored by Sucrose and DA-6 Treatment

“…Among them, FUM, MDH, and ODGH may be targeted for TCA pathway regulation [ 46 ]. Furthermore, the PPP is a supplemental source of energy metabolism that directly oxidizes sugar and complements glycolysis to provide cells with NADPH and material to sustain seed germination, as well as providing pentose phosphate for nucleotide metabolism [ 47 ], the expression of its key genes was also down-regulated ( Table S1 ). Taken together, it appears that the entire energy supply chain in safflower seeds is severely damaged during the aging process and increasingly fails to provide sufficient energy for seed germination and seedling establishment.…”

Influence of Seed Development and Maturation on the Physiological and Biochemical Seed Quality

“…Condensed tannins, a group of flavonoids were observed to increase throughout seed development in common bean and decreased after seed maturation [69]. A study in Magnolia zenii Cheng revealed a significant increase in soluble sugar, protein and lipid content of seed between 30 to 165 DAF [70]. In capsicum baccatum, [51] observed that soluble protein content increased by 66% from 10 to 40 DAA and remained unchanged until last harvest at 80DAA while neutral lipids content increased 14-fold between 10 and 30 DAA, reduced from 30 to 60 DAA and later increased until 80 DAA.…”

Insights into the regulation of energy metabolism during the seed-to-seedling transition in marine angiosperm Zostera marina L.: Integrated metabolomic and transcriptomic analysis

“…The pentose phosphate pathway is a supplementary source of cellular energy that can directly oxidize sugars and complement glycolysis to provide the cell with NADPH and materials to promote seed germination (Wang et al, 2021). During the development of Arabidopsis, G6P is metabolized to erythrose 4phosphate, ribulose 5-phosphate, and sedoheptulose 7-phosphate with the release of NADPH and ATP through the pentose phosphate pathway to promote plant development (Andriotis and Smith, 2019).…”