An Introduction to Parthenocarpy

A brief presentation on the toipc of Parthenocary. This topic has created by me after study many books, journals and online educational websites.

1. An introduction to Parthenocarpy Presented By :- Vikas Kumar Student of B.sc Agriculture Gochar mahavidyalya Rampur maniharan saharanpur

2. Introduction What do bananas and figs have in common? They both develop without fertilization and produce no viable seeds. This situation in plants is called Parthenocarpy. Parthenocarpy is a very old procedure to produce seedless fruit. The oldest known cultivated plant is a Fig. This parthenocarpic Fig was grown at least 11200 years ago. Up to 20% of the wild fruits are parthenocarpic . When pollination is unsuccessful it may be an advantage to a plant because it is helpful to provide food for the plant’s seed disperse.

3. Parthenocarpy: definition Parthenocarpy is derived from greek words “ parthenos ” means “virgin” and “ karpos ” means “fruit.” Parthenocarpy introduced by Noll in 1902. Parhthenocarpy may be defined in following ways:- “Natural or artificially induced fruit development without pollination and fertilization.” In boatany and horticulture :- “Parthenocarpy is the natural or artificially induced production of fruit without fertilization of ovules, which makes the fruit seed less.”

4. 1. Genetical Parthenocarpy Common Cultivated in wild plants. Mutations, Hybridization, Incompatibility are the reasons responsible for genetical parthenocarpy. In incompatible plants, pollen tube growth is extremely slow and flowers fall much before the tube reaches the ovary. In natural genetical parthenocarpy is associated with high auxin content and are triploids i.e. Grapes.

5. 2. Environmental Parthenocarpy Climatic factors like Fog, Temperature particularly noctural temperature. The low temperature slow down pollen tube growth and pollen tube fails to reach the ovary. In cucurbits pepo , preventing the pollination factor and subjecting the plant to 15c during night can induce the parthenocarpy. Low temperature and short day promote pistillate flowers in cucurbits and inhibits flower abscission in tomato and thereby promote parthenocarpy.

6. 3. Chemically induced Parthenocarpy Gustafson (1939) made a comparative study of hormones in seeded fruits and found that seedless varieties have bigger Auxin content. Auxin application in plants prevent abscission layer and encourage the development the vascular system in the stalk, brings abortion of seeds and reduces water loss from fruits. Vegetative parthenocarpy can be induced in Morus alba if pollination is prevented through bagging.

7. Types of Parthenocarpy: on the basis of pollination Parthenocarpy on the basis of pollination can be categorized into two parts:- Vegetative Parthenocarpy :- This generally takes place without pollination and due to the absence of pollination, no seeds are produced within the fruits. Seedless cucumber, Pear and Fig are the examples of vegetative parthenocarpy.

8. 2. Stimulative Parthenocarpy :- If a fruit develops from the stimulus of the pollination (but without fertilization) , this phenomenon is known as stimulative parthenocarpy. E.g. Seedless Watermelon, Papaya. Etc.

9. 3. Steno-spermocarpy:- In Black Corinth variety of grapes, pollination and fertilization take place but the embryo gets aborted subsequently resulting in seedlessness. This phenomenon of development of seedless fruits is referred to as steno-spermocarpy. e.g. Seedless Grapes , guava or oranges .

10. Factors affecting Parthenocarpy Environmental factor (High or low temperature). Chromosomal abrreation ( Genetical Disorder). Growth regulator. Self Incompatibility. Genetic factors like gene controlling meiosis.

11. Causes and induction of parthenocarpy of fruit crops:- Fruit Crop Causes Guava e.g. Allahabad Seedless Due to triloidy . Failure of fertilization of well differentiated ovules. Degenration of fertilized ovules. Grape Due to embryo abortion. Citrus Due to Self- incompatibilty ( Madarin ) Cytoplasmic male sterility (Satsuma Mandarin) Chromosomal irregularities (Tahiti Lime, Oroblanco , Melogold ) Apple Lack of pollination. Banana Due to triploidy .

12. Advantages of parthenocarpy This is more healthy and the results are achieved easily. Provides seedless fruits and improve quality. It reduces the complete cost of production. It improves crop yields without using organic pesticides. Parthenocarpy can reduce the total time required by a crop. Parthenocarpy keeps the insects and pests away because there is no need of insects for pollination. Parthenocarpy is a require trait at present in edible fruit such as banana, pineapple, grape, orange, tomato and summer squash.

13. Disadvantages of Parthenocarpy Seedless fruits can not be used to produce the new progeny of any plants. The seed is only the medium by which any plant can be produced. Parthenocarpy is undesirable in nut crops because there seed is the edible part. Quality and size of fruits get changed in case of parthenocarpuc fruits as compared to the natural fruits.

14. Limitations in parthenocarpy Lack of stability and uniformity in the expressions of parthenocarpy. Small sized fruits. Presence of knots or malformed fruits. Hampers the production of commercial seeds.

15. Future Thrust High level and stable parthenocarpy. Combining several parthenocarpy genes. Developing parthenocarpy in high value crops. Combining parthenocarpy with male sterility.

16. Parthenogenesis Parthenogenesis is derived from Greek words “ parthenos ” means “virgin” and “genesis” means “creation”. Parthenogenesis is the development of a zygote from the egg cell without act of fertilization. This is found in many lower plants e.g. spirogyra, chara , mucor , certain ferns and certain species of selaginella . In some flowering plants and certain species of compositae and Solanaceae . It is two types:- Gonial Parthenogenesis. Somatic Parthenogenesis.