An optimized histological proceeding to study the female gametophyte development in grapevine

Area of Science:

• Plant reproductive biology
• Angiosperm embryology
• Plant histology

Background:

• Successful seed and fruit set in plants relies on functional female gametophytes.
• Existing grapevine embryo sac analysis methods are often lengthy and complex.
• Safranin O and fast green FCF staining offers a simpler alternative for plant embryology.

Purpose of the Study:

• To detail a streamlined paraffin-embedding protocol for grapevine ovule histology.
• To establish an efficient method for observing megasporogenesis and megagametogenesis in grapevine.
• To provide a viable staining technique for routine screening of grapevine ovules.

Main Methods:

• Paraffin-embedding of grapevine ovules at various phenological stages.
• Sectioning at 5 µm thickness.
• Staining with safranin O and fast green FCF.

Main Results:

• A 1.5-day histological sample preparation process was established.
• The method yields sections with good contrast using safranin O and fast green FCF.
• Megasporogenesis and megagametogenesis events were observable across different phenological stages.

Conclusions:

• The described paraffin-embedding method is suitable for routine histological analysis of grapevine ovaries.
• The safranin O and fast green FCF staining combination is a simple and effective technique.
• This method facilitates basic screening for normally developed ovules and potentially functional embryo sacs in grapevine.