Accessory fruit

Incorporated organs

The following are examples of accessory fruits listed by the plant organ from which the accessory tissue is derived:

Fruit with fleshy seeds, such as pomegranate or mamoncillo, are not considered to be accessory fruits.

Examples

Apples and pears

The part of apples and pears that is consumed is, in fact, the hypanthium. The ovary is the papery core that surrounds the apple seeds. As the hypanthium ripens it forms the edible tissues.

Roses

For roses, the hypanthium is the tissue that composes the edible part of rosehips. Roses and apples are both members of the Rosaceae family; the fact that they have similar fruit morphology is a major consideration in placing them in the same taxonomic family.

Strawberries

The edible part of the strawberry is formed, as part of the ripening process, from the receptacle of the strawberry flower. The true fruits (hence, containing the seeds) are the roughly 200 pips (which are, technically, achenes, a true fruit that contains a single seed from a single ovary). These pips dot the exterior of the strawberry.

Cashew apple

The cashew apple is an oval- or pear-shaped structure that develops from the pedicel and the receptacle of the cashew flower and is technically called a hypocarpium. It ripens into a yellow or red structure about 5–11 cm long. The true fruit of the cashew tree is a kidney–shaped drupe that grows at the end of the cashew apple; the seed inside this drupe is the cashew nut of commerce.

Pineapple

The pineapple is formed when 50 to 200 unpollinated flowers coalesce in a spiral arrangement— the flowers form individually and then fuse as a single 'multiple fruit'. The ovaries develop into berries and the fruit forms around an intercalary spike. The intercalary inflorescence (cluster of flowers) results when the terminal cluster of flowers are left behind by the growth of the main axis of the plant. Each polygonal area on the pineapple's surface is an individual flower.

Research

Current research has proposed that a single class of genes may be responsible for regulating accessory fruit formation and ripening. A study using strawberries concluded that hormone signaling pathways involving gibberellic acid and auxin affect gene expression, and contribute to the initiation of accessory fruit development. Metabolic modifications in different developing accessory fruit tissues are due to the varied distributions of compounds such as triterpenoids and steroids.

References

References

1. Esau, K. 1977. ''Anatomy of seed plants''. John Wiley and Sons, New York.
2. "Glossary Details – The William & Lynda Steere Herbarium".
3. Merriam Webster Collegiate Dictionary entries for [http://www.merriam-webster.com/dictionary/syconium ''syconium''], [http://www.merriam-webster.com/dictionary/accessory_fruit ''accessory fruit''], [http://www.merriam-webster.com/dictionary/core ''core''], and [http://www.merriam-webster.com/dictionary/strawberry ''strawberry''], Merriam-Webster, Inc., 2006
4. (2009). "Pomegranate: Botany, Horticulture, Breeding". John Wiley & Sons, Ltd.
5. Michaels, Tom. (2022-06-20). "The Science of Plants".
6. (1964). "Anatomy of the pseudocarp in ''Anacardium occidentale'' L.". Proceedings of the Indian Academy of Sciences, Section B.
7. (1983). "''Anacardium occidentale'' L.". Handbook of Energy Crops. (unpublished); In: NewCROP, New Crop Resource Online Program, Center for New Crops and Plant Products, Purdue University.
8. (7 April 2020). "Cashew". Encyclopedia Britannica.
9. Morton. (1987). "Cashew apple, ''Anacardium occidentale'' L.". Center for New Crops and Plant Products, Department of Horticulture and Landscape Architecture, Purdue University.
10. "Plant Details – Information about Ananas comosus Plant".
11. (13 December 2012). "Apple SEPALLATA1/2-like genes control fruit flesh development and ripening". The Plant Journal.
12. (March 2021). "Gibberellin and auxin signaling genes RGA1 and ARF8 repress accessory fruit initiation in diploid strawberry". Plant Physiology.
13. (25 August 2021). "Distribution of Triterpenoids and Steroids in Developing Rugosa Rose (Rosarugosa Thunb.) Accessory Fruit". Molecules.