Effects of Flooding Stress on Growth and Root Physiology and Biochemistry of Grafted Red-seed Watermelon Seedlings

[Objectives]This study was conducted to explore how to improve the waterlogging tolerance of red-seed watermelon through grafting,to provide a theoretical basis for its cultivation in rainy season.[Methods]The effects of flooding stress on the growth and root physiological and biochemical characteristics of grafted and own-rooted red-seed watermelon seedlings were studied using Luffa as rootstocks and"Zhongxin 1"red-seed watermelon as scions.[Results]After flooding stress,the biomass and root activity of grafted seedlings of red-seed watermelon were significantly higher than those of own-rooted seedlings.With the prolongation of flooding stress time,the soluble sugar and proline content showed a trend of first increasing and then decreasing,and the grafted seedlings had a larger increase and a smaller decrease,and were always significantly higher than own-rooted seedlings in the same period.The content of malondialdehyde in the root system of grafted seedlings increased first and then decreased,while it continued to increase in own-rooted seedlings,and the increase in own-rooted seedlings was significantly greater than that in grafted seedlings during the same period.[Conclusions]Grafting on Luffa rootstocks could improve waterlogging tolerance of red-seed watermelon.

Heritability of Main Yield Traits in Red-seed Watermelon and Their Correlation Analysis

[Objectives]This study was conducted to provide a reliable theoretical basis for the correct formulation of breeding programs for red-seed watermelon and the effective breeding of hybrid offspring.[Methods]With local varieties and inbred lines of red-seed watermelon as test materials,the generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were estimated by variance analysis;and the heritability,genetic variation coefficients,and correlation of the nine yield traits in 43 red-seed watermelon varieties were studied.[Results]The generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were 12.86%,80.14%,75.96%,74.39%,48.01%,17.12%,24.97%,18.60%,and 37.07%,respectively.The heritability of single-fruit weight,single-fruit seed number and single-fruit seed weight was higher,and early-generation individual selection could achieve a better effect on them;and 1000-seed weight and kernel-producing ratio had a higher coefficient of genetic variation,indicating a high selection potential.[Conclusions]Indirect selection could be achieved for traits such as the single-fruit seed number,single-fruit seed weight,seed kernel weight,and seed volume by selecting the single-fruit weight.In the process of red-seed watermelon breeding,traits with high heritability can be selected in early generations of hybrids,thus playing the role of early-generation orientation.

In vitro Screening of Fusarium Wilt-resistant Germplasm Resources of Red Edible Seed Watermelon( Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao)

[Objective]This study aimed to establish an appropriate technology system for in vitro screening of Fusarium wilt-resistant germplasm resources of red edible seed watermelon and obtain variants resistant to fusaric acid,thus providing resistant materials for breeding Fusarium wilt-resistant red edible seed watermelon. [Method] Using Zhongxin No. 1 red edible seed watermelon adventitious buds as screening materials and fusaric acid( FA) as a stress agent,in vitro screening of Fusarium wilt-resistant red edible seed watermelon clonal variants and identification of Fusarium wilt-resistance of the germplasm resources of red edible seed watermelon were performed. [Result]The results showed that the appropriate FA for in vitro screening of Fusarium wilt-resistant red edible seed watermelon variants was 15 mg/L. In vitro screening system for Fusarium wilt-resistant red edible seed watermelon variants was established preliminarily and FA-resistant regenerated plants were obtained. Among the 36 germplasm resources of red edible seed watermelon,there were 2 highly resistant materials,6 moderately resistant materials,11 slightly resistant materials and 17 highly susceptible materials. [Conclusion]This study confirmed preliminarily that in vitro screening method is effective for obtaining resistant materials of red edible seed watermelon.

Comparative Study on Clinical Characteristics and Outcomes of Overt Diabetes Mellitus and Gestational Diabetes Mellitus in Late Pregnancy

Background: With the rising prevalence in recent years, gestational diabetes mellitus has become one of the leading causes of maternal and child mortality and morbidity worldwide and has raised health concern. It is seriously detrimental to both the women and fetuses. However, there are limited evidences of two types of gestational diabetes mellitus on clinical characteristics and outcomes. Therefore, this study was aimed to explore the clinical characteristics and outcomes of patients with overt diabetes mellitus (ODM) and gestational diabetes mellitus (GDM) at the late pregnancy. Methods: From January 2015 to August 2016, totally 63 gestational diabetes mellitus from the Department of Clinical Nutrition in Beijing Anzhen Hospital were enrolled in the study. Patients were classified into two groups. 31 patients with gestational overt diabetes mellitus were grouped into ODM group and 32 patients with gestational diabetes mellitus were grouped into GDM group. Clinical characteristics and outcomes were compared between ODM and GDM. We collected records of the age, gestational week, family history, past history, pregnancy complications, insulin use, blood pressure, clinical nutrition indexes, blood pressure. Glycosylated hemoglobin (HbA1c), fasting blood glucose (FBG), total protein (TP), albumin (ALB), prealbumin (PALB), hemoglobin (HGB), urea nitrogen (BUN), serum creatinine (CREA), and dynamic blood glucose monitoring were measured. And we recorded the changes of blood glucose and the test data. We statistically analyzed the data of two groups. Results: In the ODM group, HbA1c, FBG, average blood glucose, two-hour postprandial blood glucose (2hPBG) after breakfast, 2hPBG after dinner, the number of hyperglycemic events and high blood glucose time ratio are significantly higher than those of GDM and two groups compared with statistical significance (P < 0.05). The number of patients treated with insulin (10/31) in ODM is significantly more than that in GDM (1/32) (P < 0.05). 45% (14/31) of ODM have a family history of diabetes patients. The ratio is significantly higher than 13% (4/32) of GDM (P < 0.05). There was significant difference in urinary ketone positive rate between the two groups (P < 0.05), but there was no significant difference in urinary microalbumin abnormal rate between them (P > 0.05). The number of preeclampsia in ODM (8/31) is significantly higher than that of GDM (P < 0.05). The level of HGB in ODM is lower than that of GDM (P < 0.05). There was no difference in the pregnancy outcomes between the two groups. Conclusion: Late pregnancy women with ODM have obvious family history, higher HbA1c, higher FBG, higher glucose levels of two-hours after breakfast and dinner, higher average blood glucose, longer hypoglycemia time, higher probability of hyperglycemic events and greater opportunity to use insulin in the treatment of symptomatic patients, higher risk of preeclampsia, lower HGB level than GDM, while GDM has higher positive rate of urine ketone than ODM.

基于实证分析的出版业知识服务技术应用研究

数字经济时代,知识资源已成为我国重要战略资源和生产要素,技术赋能下的知识服务成为数字时代出版服务的重要方式,也是落实出版深度融合的重要抓手。文章采用问卷调研和案例征集的方法,从出版业知识服务的5个环节,即知识资源获取、知识资源组织、知识资源发布、知识应用服务、知识服务运营方面研究各环节技术应用现状及场景,分析现存问题并提出发展建议。