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    Construction and Exploration of Teaching Reform about the Horticultural Plant Biotechnology Course

    2020-12-27 02:47:19
    Asian Agricultural Research 2020年1期

    College of Horticulture, Hainan University, Haikou 570228, China

    Abstract Horticultural Plant Biotechnology is a core course of undergraduate teaching of horticulture with high practicality. For students, its contents are too complex and abstract to master. In order to strengthen the teaching effect of the course, stimulate students’ interest in learning, improve students’ ability to analyze and solve problems, this article makes an in-depth analysis of the complicated and abstract knowledge points, the endless emergence of new knowledge, the disconnection between practice and experimental teaching in the Horticultural Plant Biotechnology course. Based on the analysis, it puts forward the reasonable and blend methods of online teaching, to cultivate innovative and practical ability of students.

    Key words Horticultural Plant Biotechnology, Teaching reform, Online teaching

    1 Introduction

    Aiming at producing products for people, or achieving a certain purpose, biotechnology is a comprehensive subject based on modern life sciences to transform organisms or process biological materials with biological systems and engineering principles. Biotechnology mainly includes the fields of cell engineering, genetic engineering, enzyme engineering, fermentation engineering, protein engineering,etc. It is the core content and pillar industry of the high-tech revolution, and has been widely used in scientific research and industrial development of agriculture, forestry, animal husbandry, fisheries, medicine, food,etc. The Horticultural Plant Biotechnology course is an important part of biotechnology. It is a technology that takes horticultural plants as the main study object to create improved germplasm or produce biological products. As an interdisciplinary subject of horticulture and biotechnology, it mainly includes horticultural plant tissue culture, cell engineering, molecular markers, genetic engineering,etc. With the rapid development of modern agriculture, the close combination of modern biotechnology and traditional agricultural technology has become an important tool in the field of horticultural plant research.

    In recent years, huge economic benefits have been obtained due to wide application of the rapid propagation of seedlings, detoxification technology, and transgenic technology in production practices of horticultural crops. As people continue to study the important subjects of horticultural plant breeding, quality formation, resistance to diseaseetc. to the molecular level, the impact of biotechnology on the field of horticulture is becoming more and more far-reaching. Cultivating a large number of innovative and applied talents with modern biotechnology knowledge has become increasingly important and urgent. For the above reasons, the Horticultural Plant Biotechnology course has been opened successively in the majors of horticulture in agricultural colleges and comprehensive universities, and it plays an important role in the construction of horticultural courses.

    The ultimate goal of the teaching and reform of this course is to make students become interested in the technology and truly master practical skills, guide them to germinate innovative ideas and lay the foundation for serving the society in the future by infiltrating the latest research progress at home and abroad into the teaching of horticultural plant biotechnology within the limited class hours. The knowledge system of the Horticultural Plant Biotechnology course has been updated rapidly, resulting in heavy teaching tasks. In the course of Horticultural Plant Biotechnology, students often complained that the content of the course was so abstract that the teaching effect was not satisfactory. Therefore, we intend to analyze the main problems in teaching of this course in this paper, and come up with recommendations accordingly.

    2 Current problems

    2.1 Too complex and abstract knowledge pointsThe Horticultural Plant Biotechnology course involves many knowledge points and large amount of information, while the theoretical hours of the course are only about 30, which makes it difficult to complete an extensive and comprehensive teaching contents within the given time. According to the requirement and arrangement for undergraduate teaching of horticulture, the courses which are based on the study of botany, biochemistry, plant physiology and genetics, need strong supports of the relevant basic theoretical knowledge, especially in biochemistry and genetics.

    However, in practical teaching, many students do not have a solid grasp of the basic knowledge of biochemistry and genetics, and the learning foundation is relatively weak. Thus, it is difficult for students to fully grasp some important knowledge points. Many contents of the Horticultural Plant Biotechnology course are very abstract, so it is difficult to achieve the ideal teaching effect by using traditional teaching methods. In order to teach as much theoretical knowledge as possible in limited time, teachers usually use the traditional "spoon-feed" methods in the classroom. However, many basic concepts involved in this course, such as gene cloning and DNA, are microscopic. They are so obscure that many students complain they can’t understand after class. As a result, it greatly reduces their enthusiasm of learning. Teachers only pay attention to the transfer and indoctrination of knowledge in the classroom. The lack of effective interaction between teachers and students makes teaching dull, tedious, and inefficient. Students simply receive knowledge and lack proactive thinking. Therefore, how to make full use of modern teaching methods, overcome the shortcomings of traditional teaching methods, and improve efficiency and effect of teaching is a major problem during the teaching reform of the course.

    2.2 Rapid update of knowledgeThe Horticultural Plant Biotechnology course is an emerging and interdisciplinary subject, and knowledge points are updated at a rapid pace. In the actual teaching, the limited class hours make it difficult to complete the basic and new knowledge systematically. Many teachers still prefer to teach classic theoretical knowledge in textbooks, such as plant tissue culture and virus-free technology. The obsolete teaching contents make it difficult for students to keep pace with the development of the times. Even if some emerging technologies, such as RNAi and gene editing, are introduced into the classroom, they fail to completely be explained in detail. Consequently, students’ knowledge and skills are outdated, and it is difficult for them to keep pace with the ever-changing subject situation.

    2.3 Highly practical but difficult to fully implement experimental teachingThe Horticultural Plant Biotechnology course aiming at introducing relevant biotechnological means to students ,guiding them to apply the means to the fields of horticultural plant research and production on the basis of mastering these technologies, has strong practicality. As an important part of the course teaching, experimental teaching can truly test the students’ grasp of the course theory, and help them deepen their understanding and mastering of abstract and incomprehensible theoretical knowledge with systematic experimental operations.

    The smooth development of experimental teaching is extremely important for students to be proficient in the theoretical contents of the courses. However, the experimental contents of the Horticultural Plant Biotechnology course is very complicated, involving several modules of horticultural plant such as genetic engineering, tissue culture, cell engineering, molecular markers,etc., and each module involves many basic experimental skills. For example, there is a common problem of less experimental hours in the most important genetic engineering module which includes gene cloning, nucleic acid extraction, PCR amplification, enzyme digestion, vector construction, genetic transformation, and identification of transgenic plants, so that students do not have enough time to systematically complete any experimental module of horticultural plant biotechnology. Not only that, some experiments such as tissue culture, establishment of protoplast regeneration systems, have a long period of time. It takes several months to accomplish a complete experimental cycle. This kind of experiment, hard to be brought into the experimental teaching category of the course, is very important for students to understand and master related theoretical knowledge. Therefore, it is urgent to reform teaching methods and seek other ways to show the corresponding experimental techniques to students when they are studying related theories.

    In the actual experiment classes of the traditional teaching, teachers prepare the experimental reagents required before class. In the class, teachers will teach students the experimental purpose, materials and steps, and students will follow the teacher’s explanation step by step. When the experiment is completed, students just write down the results in a few sentences on the experiment reports. During the whole process, students lack the ability to create their own works, but only carry out experiments according to the experimental steps, which results in a great reduction in the effect of experimental teaching.

    3 Thoughts and suggestions on improving the teaching quality

    3.1 Reasonable use of online teaching methodsWith the continuous exploration of "Internet+Education" and development of education informatization and internet education industrialization, the current network resources of higher education have changed college students’ tendency of autonomous learning. The teaching methods of autonomous learning mode based on the Internet is gradually in a dominant position in the daily education and teaching of colleges. Gradually implementing online teaching of the Horticultural Plant Biotechnology course by paying attention to the construction and reasonable application of modern Internet teaching methods, can greatly increase the amount of teaching information per unit time and effectively improve teaching efficiency. Teachers can implement multimedia and network in teaching by uploading teaching courseware, electronic lesson plans, electronic question banks,etc. to online teaching platforms . In this way, students can preview and review courses with learning coursewares after school, so that classroom teaching will be organically combined with extracurricular learning. It will help students gain a more thorough understanding and mastery of various knowledge points. With the help of the internet platform, teachers can also introduce new technologies and knowledge to students that could not be taught in limited class time, to reconstruct the curriculum knowledge systems and greatly expands the knowledge boundary of the curriculum. In addition, because many aspects of the Horticultural Plant Biotechnology course such as PCR and molecular hybridization, are relatively abstract for undergraduates who have not engaged in related research, some related animations and videos can be collected to make the teaching contents easily understood. The rich audiovisual materials will provide strong supports for the teaching of courses, enhance students’ perceptual knowledge of the teaching contents, and achieve good results that cannot be achieved by using language description alone. In terms of experimental teaching, the experiments related to the Horticultural Plant Biotechnology course can be classified into several modules such as genetic engineering, tissue culture, cell engineering, molecular markers,etc. The vivid teaching materials of each module can be used on the Internet platform, and each experimental link is introduced in detail to allow students to use extracurricular time for systematic learning. It will help students to have a deeper understanding and mastery of the Horticultural Plant Biotechnology course which has high practicality. In particular, some experiments are too long to be implemented in class, but allowing students to perceive them with learning some materials such as PPT, animation, video, will get better learning results.

    3.2 Blending the teaching methods to cultivate students’ ability of innovation and practiceIn the traditional teaching, teachers are the main body of teaching activities and the imparters of knowledge, while students are inculcated. The teaching mode is not conducive to train students’ creative thinking and ability because of ignoring the role of students’ cognitive subject. Under the premise of the continuous development of internet teaching, the emergence of blended teaching mode provides new ideas for the reform of education and teaching.

    In the internet teaching of horticultural plant biotechnology, students use the extra-curricular time to learn the knowledge of the course systematically. Certainly, it is inevitable for students to meet some contents difficult to understand. In this case, using blended teaching mode can not only give play to the leading role of teachers in guiding, enlightening, and monitoring the teaching process, but also fully reflects the initiative, enthusiasm, and creativity of students as the subject of the learning process. Students’ understanding of the course will be greatly improved when students ask teachers more targeted questions in the classroom initiatively and solve these problems under teacher’s guidance. Moreover, the significance of adopting the blended teaching mode in experimental teaching is even greater. In traditional experimental teaching, teachers prepare the reagents required for the class, and inculcate the experimental purposes and steps to the students, while the students carry out the experimental operations step by step. It is uncreative during the whole process. Teachers mostly chose simpler confirmatory experiments. By comparison, in the blended teaching mode, students can learn experimental knowledge points through the Internet platform. In the real offline experimental teaching, teachers can make some reforms and give some more complex and open comprehensive experimental topics. Students are divided into several groups to discuss how to disassemble the comprehensive experimental topics into a series of basic experimental operations or techniques, establish a corresponding experimental plan and carry out experiments based on this. It means to provide students the opportunity to apply the knowledge in the class. It will greatly improve students’ understanding of the curriculum knowledge points, and cultivate the ability of theory, practice, innovation. It helps students change from studying mechanically to mastering really the knowledge of the Horticultural Plant Biotechnology course.

    4 Conclusions

    In the 21st century, higher requirements have been placed on education standards and methods. So teachers must not only continuously improve their teaching standards, academic standards, practical abilities and teaching attitudes,etc., but also comprehensively reform traditional teaching contents and methods. These require college teachers to devote themselves to teaching research and exploration, and always think about how to continuously improve teaching methods to make them more flexible and better satisfy the needs of students, in order to increase learning interest and stimulate innovative thinking of students. Biotechnology is a rapidly developing modern science. Its combination with plant science and agricultural science has created a large amount of new knowledge, new technologies and new research fields.

    Therefore, the teaching of the Horticultural Plant Biotechnology course must also keep pace with the times, and constantly adjust teaching methods to cultivate professional undergraduates who closely follow the development of science and technology, and meet the growing demand of society for high-quality, comprehensive and innovative agricultural talents.

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