Pollination Biology of Lespedeza davurica

Background: In order to reveal the pollination biological characteristics of Lespedeza davurica, wild L.davurica from eight regions of Shanxi Province was used as test materials to study their floral dynamic, pollen storage and other aspects.Methods: During 2019, the flowering dynamics of wild L. davurica collected from eight regions of Shanxi Province were observed by selecting the better-grown L.davurica. Freshly bloomed flowers were picked, and their pollen was set up for two treatments, dry and undried, for pollen storage experiments. Pollen viability was determined by the TTC (expand for first instance) and MTT (expand for first instance) methods and stigma receptivity was determined by the hydrogen peroxide-benzidine method.Result: The results showed us the following points: the flowers of L. davurica were pale yellow, large and fragrant; it usually opens from the base to the top with distinctly asymmetrical petals; it opens during the day and closes at night; the number of flowers reached its peak between 12:00 and 14:00. After measuring the pollen viability of L. davurica, we found that dry storage at -20°C was the most effective treatment. And with the increase of temperature and decrease of humidity, the pollen viability and stigma receptivity of L. davurica increased continuously and the highest viability value occurs between 12:00 and14:00.

Old-field Succession Sequence in Loess Area in Northern Shaanxi of China

Hierarchical clustering method was applied for division of stages of old-field succession of loess area of Northern Shaanxi, and the similarity among different communities in abandoned field of different abandoned year and site condition can be learnt quantitatively, and stages or sequence of old-filed succession can be determined. The result revealed that the stages of old-field succession are: polydominant association of annual weed artemisia scoparia and other perennial herbage→Lespedeza davurica and perennial herbage association→artemisia vestita and perennial herbage association→tuft grass bothriochloa ischaemum and perennial herbage association→undershrub Buddleja alternifolia association. Among them, the appearance of shrub association (undershrub Buddleja alternifolia) contrasts results in former studies that it was impossible to form shrub association in loess area of Northern Shaanxi. Thus, this study is not only a complement of former studies, but also a new discovery and innovation.

Lespedeza davurica(Lax.) Schindl. Extract Protects against Cytokine-Inducedβ-Cell Damage and Streptozotocin-Induced Diabetes

Lespedezahas been used for the management of diabetes in folklore medicine. The purpose of this study is to investigate the protective effects of the methanol extract ofLespedeza davurica(LD) on cytokine-inducedβ-cell damage and streptozotocin- (STZ-) induced diabetes. RINm5F cells were treated with interleukin- (IL-) 1βand interferon- (IFN-)γto induce pancreaticβ-cell damage. The exposure of LD extract significantly decreased cell death, nitric oxide (NO) production, nitric oxide synthase (iNOS) expression, and nucleus factor-kappa B (NF-κB) p65 activation. Antidiabetic effects of LD extract were observed by oral glucose tolerance test (OGTT) in normal rats and by checking the biochemical, physiological, and histopathological parameters in STZ-induced diabetic rats. In OGTT, glucose clearance levels improved by oral treatment of LD extract. The water intake, urine volume, blood glucose, and serum TG, TC, TBARS, and DPP-IV levels were significantly decreased, and liver glycogen content was significantly increased by treatment of LD extract (250 mg/kg BW) in STZ-induced diabetic rats. Also, insulin immunoreactivity of the pancreases was increased in LD extract administrated rats compared with diabetic control rats. These results indicate that LD extract may protect pancreaticβ-cell damage and regulate the blood glucose in STZ-induced diabetic rats.