No abstract

No abstract

Each organ plant has been formed perfectly to support physiological processes in an unfavorable environmental condition. Rice (Oryza sativa L.) be included plants sensitive to drought conditions during a stage of growth and development. This will cause pressure (stress) resulting in a decrease in rate metabolism in leaf cells. Leaf anatomical characteristics are criteria that can be used to identify plants that are tolerant to drought. Anatomical response leaves in drought conditions inform the development of leaf photosynthetic parts carrying out changes in anatomical structure morphology includes changes in cell walls, organ size, changes in direction growth, including dropping leaves and enhancing the life cycle. The research aimed to determine the anatomic response leaves rice varieties (Oryza sativa L.) to drought stress. Five rice varieties used were given drought-stress treatment for 12 days. Identification leaf anatomical structures using microscopic slices of transverse was made according to the paraffin method. Changes in the anatomical structure of leaves of drought-stress have decreased bulliform cells increase in size, the thickness epidermis cells in an effort to retain the water content in cells, and reducing the size and total stomata with purpose process control flow of transpiration and water use efficiency.

Rice is an important food crop that consumed by more than half of the world's population, but almost every year there is decrease rice production in field, this is due availability of land and water as main source of agriculture. Therefore optimization of dry land as agricultural is needed, but many things are of concern to dry land, especially water sources are minimal. Therefore, it is need have rice seeds are suitable and adaptive to dry land, the response of rice plants to drought can observed from physiological, morphological and anatomical changes. This research was conducted in August to December 2018 in research laboratories, wire houses and plant physiology laboratories, Faculty of Mathematics and Natural Sciences, Padang State University. This study was to obtain a drought tolerant morphological index from several paddy seeds in West Sumatera, so indexes showed that rice seeds were tolerant to drought by observing morphological changes, namely leaf rolling (DPD), shoot top index (IKP). ), and plant recorvry (TP) using the SES (Standard Evaluation System) method for rice. Data is processed using cluster analysis with hierarchical analysis methods. The results showed the most resistant varieties to drought stress were’s Baroto, Situ Bagendit, Randah Kuniang, and Harum.

Penelitian ini bertujuan untuk mengetahui analisis e-learning dalam pembelajaran evolusi mahasiswa pendidikan biologi selama pandemi covid-19. Penelitian ini adalah penelitian studi pustaka (library research). Sumber data berasal dari jurnal nasional dan internasional bereputasi, buku dan sumber relevan lainnya. Teknik pengumpulan data dengan menelusuri jurnal dan buku yang berkaitan dengan kemampuan metakognitif mahasiswa. Hasil penelitian ini disimpulkan bahwa pembelajaran e-learning selama Covid-19 berjalan dengan efektif dalam pembelajaran evolusi dan memberikan kemudahan kepada mahasiswa dalam memahami materi pelajaran.