Are seedless grapes really injected with birth control pills?

I believe many people have heard reports about seedless grapes being grown using contraceptives, so many people usually dare not buy seedless grapes. In fact, seedless grapes are not necessarily grown using contraceptives. Although seedless grapes do not contain seeds, they are a special variety. They are more expensive than ordinary grapes, and the cultivation process is more difficult, so seedless grapes can be eaten with confidence.

Rumor : Seedless fruits contain large amounts of hormones and are processed with contraceptives to achieve the seedless effect. Frequent consumption is harmful to the human body.

Fact : Seedless fruits do not have viable seeds to reproduce. But the creation of seedless fruits has nothing to do with the contraceptives used by humans. Seedless fruits are grown either through breeding or treatment with plant hormones to achieve the seedless effect. These treatments do not affect the safety of the fruit.

All kinds of colorful, sweet and delicious fruits are everyone's favorite food. It is always a disappointment to bite into a hard seed while enjoying a delicious meal. So farmers and breeders worked to make them seedless by studying the developmental characteristics of the fruit. However, some people think that seedless fruits are "unnatural" and even suspect that contraceptives have been used on the fruits. This is really unfair! Let's take a look at the principle behind seedless fruits.

Why do fruits have seeds?

From a botanical point of view, the fruits we eat are basically the fruits of angiosperms. When the fruit organ appeared in the late Jurassic period, it had a sacred mission - to protect and better spread the plant larvae contained inside it: seeds. This is how the name "angiosperm" came about. The fruit coating allows the seeds to spread better, allowing us to eat delicious fruits today.

The ovary and ovules of the flower develop into fruits and seeds respectively. 2

The ovary and ovules of the flower develop into fruits and seeds respectively.

After double fertilization, the seeds begin to develop and the entire ovary is also undergoing significant changes: under the stimulation of seed activity, the ovary wall cells continue to divide and expand, making the entire ovary become enlarged and loose; at the same time, a large amount of water and nutrients (proteins, sugars, organic acids, etc.) are transported to the enlarged ovary wall cells and stored. Afterwards, under the influence of the hormone ethylene produced by the fruit itself, the entire ovary becomes thick and juicy, becoming the fruit we eat, and the seeds wrapped inside are the seeds we hate. In seeded fruits, if the ovules in the seeds do not develop, they will not be able to produce enough hormones, the ovary will wilt and fall off, and no fruit will be formed.

After understanding the process of fruit and seed formation, people realized that if they could prevent the development of seeds without affecting the development of the ovary wall, they could get seedless fruits that are both fresh and juicy without having to spit out seeds. So, people embarked on the journey of producing seedless fruits.

The power of hormones

In plants, there are two types of hormones that have the greatest impact on promoting fruit development: auxins and gibberellins. Auxin is produced by a series of enzymatic reactions from tryptophan, one of the 20 amino acids in organisms. It plays a vital role in plants. From seed germination, bud elongation to the establishment of plant morphology, the participation of auxin is indispensable.

Introduction: Recently, a video claiming that seedless grapes are grown with birth control pills went viral on WeChat Moments. In the video, a fruit vendor from an "unnamed fruit shop" was talking to someone in his car, saying that seedless grapes were "contaminated with birth control pills" and could not be given to children. What is the truth? Take a look at this article on Guokr.com. 1

Auxin promotes plant phototropism, organ growth and enlargement.

Let’s talk about gibberellins. The word "gibberellic acid" in the name of gibberellin refers to the source where it was originally discovered - Gibberellic acid. In the 1930s, Japanese scientists discovered that rice could sometimes be infected by the fungus Fusarium fusarium, with the result that the infected plants grew quite tall. By extracting and studying the secretions of Fusarium, people found that the secretions contain substances that can promote the rapid division and elongation of rice internode cells. Later, after continuous separation and purification, people discovered that this substance is actually a large class of substances with similar structures and the same physiological functions, and they collectively called these substances gibberellins. Subsequent studies also showed that plants themselves can produce gibberellins to regulate their own physiological processes. By the way, the dwarf rice that promoted the "green revolution" in agriculture is essentially the result of a mutation in a key gene in the gibberellin synthesis pathway, which leads to a disorder in gibberellin synthesis.

Rice with gibberellin synthesis disorder (left) is shorter and stronger than normal rice (right). 1

Rice with gibberellin synthesis disorder (left) is shorter and stronger than normal rice (right).

Seeing this, perhaps smart readers have already seen the clues. Auxin and gibberellin can both promote the division and growth of plant cells, and the essence of fruit development is the division and growth of ovary wall cells. The developing seeds of all angiosperms are able to synthesize large amounts of auxin and gibberellins, allowing fruits to develop. So if we can find a way to provide enough hormones to the fruit when the seeds do not develop, we can get seedless fruit.

The birth of seedless fruit

So how can we provide enough hormones to promote fruit development while the seeds are not developing? There are several methods:

1. Apply a certain concentration of plant hormones to the fruit to inhibit seed development while promoting fruit development;

2. Through hybridization, the seeds cannot develop normally, and at the same time, a certain stimulation is given so that the fruit itself can produce enough plant hormones for its development;