Plant Biology Experimental Courses in Universities: Status Quo, Limitations and Prospects

Plant biology, as a significant compulsory course for biological science students, is intuitive and practical, which plays a unique role in improving students' comprehensive quality and cultivating their innovation ability. Because of its strong practical characteristics, the experimental course is of great necessity in the study of this course. This paper analyzes the traditional teaching mode of plant biology experiment, as well as its shortcomings in modern teaching, and puts forward diversified reform methods based on the development of contemporary plant biology to promote the teaching mode of plant biology experiment to meet the needs of contemporary students on this subject. Based on the rapid development of modern science and technology, this paper includes the teaching contents, teaching methods, and assessment system of plant biology experiments, and discusses them respectively. This paper aims to improve the teaching efficiency of modern plant biology experiments and help to achieve the goal of efficiently improving students' innovation and scientific research ability.

The Making of Plant Armor: The Periderm

The periderm acts as armor protecting the plant's inner tissues from biotic and abiotic stress. It forms during the radial thickening of plant organs such as stems and roots and replaces the function of primary protective tissues such as the epidermis and the endodermis. A wound periderm also forms to heal and protect injured tissues. The periderm comprises a meristematic tissue called the phellogen, or cork cambium, and its derivatives: the lignosuberized phellem and the phelloderm. Research on the periderm has mainly focused on the chemical composition of the phellem due to its relevance as a raw material for industrial processes. Today, there is increasing interest in the regulatory network underlying periderm development as a novel breeding trait to improve plant resilience and to sequester CO2. Here, we discuss our current understanding of periderm formation, focusing on aspects of periderm evolution, mechanisms of periderm ontogenesis, regulatory networks underlying phellogen initiation and cork differentiation, and future challenges of periderm research. Expected final online publication date for the Annual Review of Plant Biology, Volume 73 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Supraspecific classification.

The definitions of genera and subgenera used in the classification of the Dacini have been in a continual state of change for over a century. The early definitions were based on often homoplasious morphological characters, some examples for the Oriental and Australian regions being Tryon (1927), Perkins (1937), Hardy (1951), May (1951) and Drew (1972). More recently revised subgeneric definitions for most species groups were published by Drew and Hancock (2016) and Hancock and Drew (2006, 2015, 2016, 2017a,b,c,d,e, 2018a,b,c, 2019), based on detailed analyses of dacine biogeography, host plant biology and morphology. This chapter discusses the evolutionary origins of the Dacini, the host plant and its influence on speciation in the Dacini.

Bryophyta (Mosses) of Senegal: the case of Mosses in Herbaria and databases

In Senegal, Mosses constitute a large and diverse systematic group. This work is a contribution to the knowledge of Bryophyta in the herbaria of Senegal. It specifically proposes to determine the structure of the Bryophyta on the prospected sites in order to provide basic knowledge for a better sustainable management. This study is carried out in the first place in the herbaria of the University Cheikh Anta Diop of Dakar/Senegal: the herbarium of the Institut Fondamental d'Afrique Noire Cheikh Anta Diop (IFAN) and the herbarium DAKAR of the Department of Plant Biology of the Faculty of Sciences and Techniques. Secondly, a consultation of different checklists and databases was conducted to collect more information. This research work on the flora of the mosses allowed us to identify a total of 70 species divided into 44 genera, 24 families and 12 orders. The orders Hypnales, Dicranales and Hookeriales are the most represented. Bryaceae are dominant followed by Pottiaceae, Calymperaceae, Dicranaceae and Hypnaceae. The genera Fissidens, Calymperes, Bryum, Gemmabruym and Leucoloma are more diversified. These results are important for the conservation of the environment and the enhancement of plant biodiversity in Senegal.

Contribution to the biosystematic study of liverworts (Marchantiophyta) of Senegal: Case of Senegaleses herbaria and check-lists

The aim of this work is to contribute to a better knowledge of liverworts in the herbaria of Senegal in order to provide basic knowledge for a better sustainable management. This study is carried out in the firstly in the herbaria of the University Cheikh Anta Diop of Dakar/Senegal: the herbarium of the Herbarium of the Institut Fondamental d'Afrique Noire (IFAN UCAD) and the herbarium DAKAR of the Department of Plant Biology of the Faculty of Sciences and Techniques. Secondly, a consultation of different checklists and databases was conducted to collect more information. This research work on the flora of liverworts is rich with nearly 39 species divided into 24 genera and 13 families. The order Jungermanniales is dominant in terms of families and the Porellales Jubulineae in terms of genera and species. The family Lejeuneaceae is in the majority in this flora before the families Ricciaceae, Plagiochilaceae and Metzgeriaceae. These results are important for the conservation of the environment and the development of the plant biodiversity of Senegal.

Long-Distance Transported RNAs: From Identity to Function

There is now a wealth of data, from different plants and labs and spanning more than two decades, which unequivocally demonstrates that RNAs can be transported over long distances, from the cell where they are transcribed to distal cells in other tissues. Different types of RNA molecules are transported, including micro- and messenger RNAs. Whether these RNAs are selected for transport and, if so, how they are selected and transported remain, in general, open questions. This aspect is likely not independent of the biological function and relevance of the transported RNAs, which are in most cases still unclear. In this review, we summarize the experimental data supporting selectivity or nonselectivity of RNA translocation and review the evidence for biological functions. After discussing potential issues regarding the comparability between experiments, we propose criteria that need to be critically evaluated to identify important signaling RNAs. Expected final online publication date for the Annual Review of Plant Biology, Volume 73 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.