Studying Autophagy and Senescence of Arabidopsis Stigmatic Cells

The pistil is the most important organ for fertilization in flowering plants, and the stigmatic papilla cells are responsible for pollen acceptance and pollen tube germination. Arabidopsis plants possess dry stigmas exhibiting high selectivity for compatible pollen. When compatible pollens are recognized and accepted by stigmatic papilla cells, water and nutrients are then transported from the stigma to pollen grains through the secretory pathway. Here, we present light microscopy-based methods for investigating autophagy and senescence of stigmatic papilla cells. These methods include the assessment of viability of stigmatic papilla cells using dual staining with fluorescein diacetate/propidium iodide, as well as the examination of vacuolar-accumulated proteins during stigma senescence. These methods can be used to understand the functions of the stigma tissue from a subcellular perspective.