Just like humans, plants need a balance of sunlight and water to thrive. But when plants receive too much sunlight, they experience a form of sunburn. More precisely, when plants are exposed to sunlight for prolonged periods of time, they dehydrate, turn yellow, wither, and die.
Plants that produce fruits and vegetables are particularly sensitive to overexposure from the sun. In fact, to protect themselves from complete dehydration, these types of crops will slow down or stop growing and reproducing, which leads to a poor harvest and low yield.
In this article, we’ll examine some of the many ways sunlight can kill crops, and how farmers can mitigate these harmful effects in order to maximize crop growth and the quality of their product.
Everything in moderation
From a farmer’s perspective, sunlight and water availability are the two most important environmental factors that affect crops. Without sunlight, plants can’t convert light energy for photosynthesis, and therefore grow to reach their full biomass.
But too much sun can cause irreparable damage to crops and disrupt their natural growth cycle. Here are a few ways in which that happens:
- Heat stress: High temperatures and excessive sunlight can accelerate the rate of water evaporation from leaves, causing dehydration and wilting, while damaging a plant’s tissues and disrupting metabolic processes.
- Sunburn: Excessive sunlight, especially during hot weather, can impair photosynthesis and cause a plant’s leaves, stems, and fruit to brown, yellow, or bleach, in effect giving it a sunburn.
- Increased transpiration: Intense sunlight increases the rate of transpiration, or the process by which plants lose water through their leaves. When water loss exceeds the plant’s ability to absorb water from the soil, it can result in dehydration, nutrient imbalances, and stunted growth.
- Over-oxidation: Plants use the molecules chlorophyll and carotenoid for photosynthesis. But when those molecules are exposed to too much sun, or overheat, they produce reactive oxygen species (ROS) that damage plant cells and tissue.
- Photoinhibition: Photoinhibition is a process where a plant’s photosynthetic management becomes overwhelmed by excessive light energy. This can be influenced by factors such as light intensity, temperature, and the availability of CO2. Photoinhibition can increase the rate of ROS, and therefore worsen oxidation.
It’s important to note that while excessive sunlight can be damaging to plant growth, it’s not the only weather condition that can cause crop failure. Both extreme rain and wind can damage plants if not properly managed or mitigated. Too much rain can lead to rotting plants, while high winds can lead to breaking and lodging, making it difficult for crops to absorb nutrients.
More control
Traditionally, farmers have used various techniques such as crop rotation, planting in appropriate locations, providing shade when needed, and using artificial lighting in controlled environments like greenhouses to manage sunlight exposure.
But today there’s a better way for farmers and commercial growers to maximize crop growth and yields. Opti-Harvest’s climate-smart Opti-Filter products are designed to help farmers harness the power of sunlight while safeguarding crops from adverse environmental damage. With Opti-Harvest, the future of sustainable agriculture and agribusiness is here.