In modern agriculture, the search for sustainable and efficient alternatives has led to the development of innovative solutions such as natural biostimulants. These products, derived from natural sources, are gaining prominence due to their ability to improve crop growth, optimize fruit quality and reduce physiological decline without resorting to synthetic chemicals. In this article, we will explore how natural biostimulants are revolutionizing hormone management in crops and offering a viable alternative for organic farming.
Fruit set is a critical stage in the cycle of any agricultural crop. After fertilization, the flower ovary transforms into fruit, and its development depends on multiple factors: variety, genetics, environmental conditions, nutrient availability, crop health and, especially, hormonal balance.
The interaction of these elements has a direct impact on fruit retention or premature fruit drop, significantly affecting productivity. For example, a prolonged drought will affect varieties with a high tendency to drop more severely, while others with greater resistance will be barely affected. Controlling these factors is essential to minimize physiological flower and fruit drop. To do this, it is necessary to implement optimal crop management that favors pollination, adequate irrigation, specific nutritional strategies, control of environmental conditions and, above all, correction of hormonal imbalances.
Hormone interaction and fruit retention
Physiological fruit drop is a complex phenomenon due to competition for carbohydrates and the interaction between plant hormones. These hormones, known as phytohormones, are key in the regulation of fruit growth, development and retention. The main hormones involved in this process are:
Abscisic acid (ABA): Associated with fruit ripening. High levels of ABA, especially under stress conditions, can induce fruit drop.
Auxins: They are crucial for fruit growth and development. High concentrations in the fruit or peduncle tissue can prevent the formation of the abscission layer, thus preventing fruit drop.
Gibberellins: Promote cell growth and can counteract the effects of ethylene on abscission.
Cytokinins: Stimulate cell division and help maintain the balance of nutrients between the fruit and the plant, which favors retention.
Ethylene: Key hormone in fruit ripening, works synergistically with abscisic acid to induce fruit drop.
Physiological fruit drop can be regulated by a correct balance between these hormones, so that an increase in the levels of gibberellins and cytokinins together with a reduction in the levels of abscisic acid and ethylene will lead to a higher fruit retention and therefore a reduction in physiological drop.
Research and development: Towards the optimization of phytoregulators
The search for artificial mechanisms to help improve plant growth conditions based on phytohormones has led to the development, thanks to biotechnology, of synthetic phytohormones that mimic the role of natural phytohormones (Johan Steven Alcántara Cortés, Acero Godoy Jovanna, Alcántara Cortés Jonathan David, Sánchez Mora Ruth Melida.2019).
Currently, around 700,000 kg/l of phyto-regulating substances are consumed in the Spanish market, with a market value of approximately 16 million euros, the main ones being synthetic auxins (2.4D, dicloprop-p, triaclopir, MCPA) and synthetic gibberellins such as gibberellic acid.
These substances are highly effective, but it is important to apply them at the right time and in a specific concentration, otherwise they could cause serious damage to the crop. In addition, they have only one permitted application and cannot be used in organic farming, leaving an ever-growing market outside their scope of application.
Evolution towards natural strategies: Is it possible?
One of the mechanisms that have not been explored to date for ripening control and fruit quality improvement, but which has great potential, is to take advantage of the mechanisms of hormone interaction in fruit development. Fruit ripening and sensory properties are not determined by a single hormone or hormone group, but by the interaction and balance between several different hormones.
The integral study at physiological, nutritional and hormonal level of a particular crop can allow to know exactly the hormonal balances in the plant during any moment or situation throughout the cycle.
The ANTIOX project, led by LAINCO in collaboration with the University of Barcelona and the company Syntech, has demonstrated that this is possible thanks to the development and marketing of 100% natural biostimulants that stimulate the control mechanisms of the hormonal balance to delay the physiological fall of the fruit in citrus, advance ripening in stone fruit trees and even increase the brix degrees in strawberries.
Laiguant Prime®: Plant biostimulant for organic farming
LAIGUANT PRIME®is presented as one of the first natural biostimulants suitable for organic farming, developed to delay the physiological fruit drop in citrus, as it does not generate residues and is free of safety period, being able to be applied until harvest time. This advantage, in comparison with chemical formulations, is combined with the possibility of repeating the application in case it is necessary to keep the fruit on the tree for a longer period of time.
LAINCO demonstrates that natural solutions are a real and effective alternative to the chemical solutions available on the market. It is possible to face the challenges of modern agriculture with sustainability and respect for the environment. This is achieved without reducing yields or the final quality of the harvest.
