RESUMO
Cytoplasmic male sterility (CMS) has long been used to produce seedless fruits in perennial woody crops like citrus. A male-sterile somatic cybrid citrus (G1 + HBP) was generated by protoplast fusion between a CMS callus parent 'Guoqing No. 1' Satsuma mandarin (Citrus unshiu, G1) and a fertile mesophyll parent Hirado Buntan pummelo (Citrus grandis, HBP). To uncover the male-sterile mechanism of G1 + HBP, we compared the transcriptome profiles of stamen organ and cell types at five stages between G1 + HBP and HBP, including the initial stamen primordia, enlarged stamen primordia, pollen mother cells, tetrads, and microspores captured by laser microdissection. The stamen organ and cell types showed distinct gene expression profiles. A majority of genes involved in stamen development were differentially expressed, especially CgAP3.2, which was downregulated in enlarged stamen primordia and upregulated in tetrads of G1 + HBP compared with HBP. Jasmonic acid- and auxin-related biological processes were enriched among the differentially expressed genes of stamen primordia, and the content of jasmonic acid biosynthesis metabolites was higher in flower buds and anthers of G1 + HBP. In contrast, the content of auxin biosynthesis metabolites was lower in G1 + HBP. The mitochondrial tricarboxylic acid cycle and oxidative phosphorylation processes were enriched among the differentially expressed genes in stamen primordia, meiocytes, and microspores, indicating the dysfunction of mitochondria in stamen organ and cell types of G1 + HBP. Taken together, the results indicate that malfunction of mitochondria-nuclear interaction might cause disorder in stamen development, and thus lead to male sterility in the citrus cybrid.
RESUMO
Objective: The purpose of this study was to help to promote a better understanding of the male fertility preservation status in China. Methods: In this cross-sectional survey, 1,912 healthcare providers and oncologists were surveyed anonymously using 16 questions carried out at community oncology practices in China from September 2018 to April 2021. 16 questions were designed to evaluate their knowledge on male fertility preservation in cancer patients, assess the factors they considered when deciding whether to discuss male fertility preservation with their patients. Results: Among the 1,912 healthcare providers (42.2% male), 1,713 (89.6%) considered that patients with cancer should be recommended for fertility preservation. 1,264 (66.1%) respondents were aware of male fertility preservation, but only 248 (13.0%) respondents knew the correct institutions. Whether a healthcare provide recommended fertility preservation to their patients depended on the provider's educational background, professional qualifications, hospital grade, area, department, and age. Among the healthcare providers, the three main factors for not recommending fertility preservation for patients with cancer were lack of suitability of the patient for fertility (28.2%), lack of knowledge of fertility preservation (28.6%), and lack of knowledge concerning the institutes that provide fertility preservation (25.4%). Conclusion: Despite this, healthcare providers and oncologists in China showed a positive attitude toward fertility preservation in patients with cancer. Hence, the education of physicians should include fertility preservation, with the aim of increasing their knowledge and awareness. There should be more collaboration between oncologists and reproductive medicine specialists.
RESUMO
Yingtan is a rapidly urbanizing city in Jiangxi Province, South China. During rapid urbanization, construction land is expanded at the expense of cropland and forest. Although economic benefits are gained, ecological and environmental damage is irreversible. In this study, a methodological framework for land use simulation using an integrated genetic algorithm-cellular automata-Markov model is proposed to assess the relationship between economic development and cropland protection in Yingtan. This framework considers both the economic and ecological benefits of different land use types. Three land use scenarios are evaluated to seek recommendations for land use practice. The results show that the areas with high suitability for cropland and construction are mainly concentrated in urban fringes. Under the green development scenario, the area of new construction land can meet the land demand for population growth and economic development proposed for 2025 based on population forecasting and government interviews. The expansion for construction land is decreased by ~ 35 km2 while the cropland area is increased by ~ 20 km2 compared with those under natural and controlled development scenarios. Additionally, ecological losses are lowest under the green development scenario. In conclusion, the green development scenario is conducive to both cropland and ecological protection, which is of relevance for future spatial planning in Yingtan.