EP-3079460-B1 - FERTILISATION INDEPENDENT FRUIT FORMATION IN EGGPLANT

Inventors

• VAN DEN ENDEN, JOHANNES HENRICUS JACOBUS

Dates

Publication Date

20260506

Application Date

20141211

Claims (11)

1. Eggplant seed capable of growing into a plant that is cytoplasmic male sterile and capable of producing eggplant fruits without fertilization, which seed is obtainable by crossing a mother plant of NCIMB 42053 with a father plant.
2. Eggplant seed as claimed in claim 1, wherein the father plant is parthenocarpic.
3. Plant grown from seed as claimed in claim 1 or 2, which plant is cytoplasmic male sterile and capable of producing eggplant fruits without fertilization.
4. Egg plant seed as claimed in claim 1 or 2 or plant grown from the seed as claimed in claim 3, wherein the eggplant fruit produced by the plant grown from the seed does not show negative pleiotropic effects.
5. Egg plant seed or plant grown from the seed as claimed in claim 4, wherein the negative pleiotropic effects are hollow core and/or deformed shape.
6. Egg plant seed or plant grown from the seed as claimed in claim 4 or 5, wherein the eggplant fruit produced by the plant grown from the seed has one or more of the following characteristics: a) a size that is similar to the size of a fruit produced after fertilization; b) a coloration and ripening process that is the same as the coloration and ripening process of a fruit produced through fertilization.
7. Progeny of an eggplant as claimed in claim 3 that has retained the cytoplasmic male-sterility and capability of fertilization independent fruit formation as found in the parent plant.
8. Propagation material derived from a plant as claimed in claim 3 that has the cytoplasmic male-sterility and the capability of fertilization independent fruit formation.
9. Propagation material capable of growing into a plant as claimed in claim 3, wherein the plant has cytoplasmic male-sterility and the capability of fertilization independent fruit formation.
10. Propagation material as claimed in claim 8 and 9 wherein the propagation material is selected from the group consisting of: microspores, pollen, ovaries, ovules, embryos, embryo sacs, egg cells, cuttings, roots, stems, cells, protoplasts, leaves, cotyledons, hypocotyls, meristematic cells, roots, root tips, microspores, anthers, flowers, seeds, callus and stems or tissue culture or parts thereof.
11. Method for the production of an eggplant having the combination of parthenocarpic fruit formation and cytoplasmic male sterility, by using a seed that comprises the combination of the traits parthenocarpic fruit formation and CMS for growing the said eggplant, wherein the seed is a seed of which a representative sample was deposited with the NCIMB under deposit number NCIMB 42053.

Description

The present invention relates to a seedless eggplant and to a method for producing such a plant. The eggplant or aubergine (Solanum melongena) is a member of the Solanaceae plant family and part of the Solanum genus which comprises more commercially interesting species such as tomato, potato and pepper. Because of its large, pendulous, purple or white fruit, the eggplant is an important food crop. It has been cultivated in southern and eastern Asian countries since prehistory but is now also grown commonly in the Western world. The fruit contains numerous small, soft seeds. From a commercial point of view seedlessness is a very desirable trait in edible fruit and vegetables, like the eggplant. The presence of seeds in ready-to-harvest fruits is considered as a negative quality. This is inter alia because seeds can lead to undesired browning of the flesh. Furthermore, seedless fruits are in general more sweet than fruits with seeds. Industrial or domestic applications which require seed removal from the fruits can also benefit strongly from the absence of seeds. Seedlessness or the absence of seeds can be the result of parthenocarpic fruit formation, where fruits set without fertilization. In certain species parthenocarpic fruit set still requires pollination or another stimulus, in particular spraying the flowers with plant growth regulators, such as gibberellin, auxin and cytokinin. This is termed artificial parthenocarpic fruit formation. Parthenocarpic fruit formation is not only interesting for obtaining seedless fruits. Unfavourable environmental conditions such as high or low temperatures and drought can hamper normal pollination which leads to poor fruit set and as a consequence yield loss. When fruit formation independent of fertilization or parthenocarpic fruit formation can be harnessed as a trait, it could significantly contribute to an economically more efficient production of eggplant fruits. In addition to contributing to harvest security, parthenocarpic fruit formation is also important for fruit quality. Parthenocarpic eggplant fruits have been mentioned to have a better flavour (less bitter) as well as a higher dry matter content as compared to seeded eggplant fruits. The higher level of soluble solids is especially important for processing eggplants which are used in industry for paste production. In addition, such fruit can be advantageous for the fresh cut industry which requires firm fruits which are not leaky. Several parthenocarpic eggplant varieties are known (e.g. Talina, Galine). During winter cultivation of such eggplant varieties fruit production may be hampered by suboptimal environmental conditions. These are usually counteracted by treating flower buds with plant growth regulators. However, these phytohormonal treatments make the production process more expensive due to the cost of both chemicals and labour. The involvement of the plant hormones auxin and gibberellin has been extensively documented although their precise role remains elusive. The application of either auxin or gibberellin to the unfertilised ovule leads in many plant species including eggplant to fruit formation. In practice, these hormones are applied to improve fruit set when greenhouse conditions are suboptimal. Although the application of auxin and gibberellin has some practical value it increases costs and it may lead to irregularities in fruit shape. In addition, the use of hormones is under discussion or prohibited in some countries. Parthenocarpic fruit formation has also been genetically engineered in eggplant by using the DefH9-iaaM gene. The DefH9-iaaM gene codes for tryptophan monoxygenase and confers auxin synthesis, while the DefH9 controlling regions drive expression of the gene specifically in the ovules and placenta. This leads to a significant increase in fruit production concomitant with a reduction in cultivation costs. However, in many countries genetically modified crops are not well accepted. Besides the above described drawbacks of the current parthenocarpic eggplants and methods available, there is another issue. An eggplant that possesses the trait parthenocarpic fruit formation can still produce fruits that contain seeds if the eggplant was able to self-pollinate in certain conditions. The quality of the eggplant fruits can be negatively influenced by the presence of seeds. As a consequence, in case one desires guaranteed seedless pepper fruit, manual emasculation (removal of anthers before maturation) of the pepper plant flowers is a necessity even if the plant itself is parthenocarpic. The prevention of self-pollination is also an issue in the production of F1 hybrid seeds. The flowers of eggplants are complete, containing both female and male structures, and may be self-pollinated or cross-pollinated. This self-pollination is non-desirable in F1 hybrid seed production, because F1 hybrid seed is produced after crossing of two different plant lines. The unwanted self-pollination can