Stress on plants can result to deficiencies plant growth and yields. In extreme levels, it can lead to permanent damage or death of the plant. Stress occurs in different forms and at different stages of the plant growth. Some stressors are naturally occurring such as wind and drought while others are caused by root disturbances, over and under-irrigation or lack of enough nutrients. In fruit farming, stress is an important factor that should be keenly looked at. This is because it can affect the performance, production, and quality of the fruits. Plant stress factors are divided into two categories;
Categories of Stress Factors
- Biotic factors
- Abiotic factors
They compete with plants for water and nutrients. Orchard owners should ensure that their gardens are free from weeds especially when the plants are still young. Planting cover crops such as legumes and mulching is recommended to minimize the growth of weeds.
Pathogens such as bacteria, viruses, nematodes, and fungi cause diseases to fruit trees which affect the yield and fruit quality negatively. They limit translocation and the plants ability to absorb nutrients from the soil. Under severe conditions, they cause chlorosis, wilting, necrosis, or even plant death. For instance, in Hass avocado, sunblotch causes stunted growth, discoloration of leaves and fruits and reduced yields.
Pests have a significant impact on the plants growth and fruit quality. If not controlled, the can damage 90 percent of the produce. In Hass avocado, mites can cause brown spots on fruits and leaves. They promote leaf and flower drop. Pests should be controlled early enough before they have devastating effects.
Diseases such as powdery mildew spread faster when the trees are poorly spaced and close together. Biotic factors can be controlled by application of good farming practices such as proper spacing, timely pruning, and employing proper irrigation methods.
These are environmental factors that affect the performance and production of the trees. They include;
Drought and wind damage
Plants such as citrus and avocados are able to tolerate drought and extreme weather conditions to some extent. However, others such as watermelon and grapes can barely tolerate drought. Harsh environmental conditions weaken the plant and low its capability to fight pests and diseases. Although drought enhances flowering, exposure for prolonged periods inhibits fruiting and fruit set.
Wind results to breakage of branches and fruit fall. It also damages plants such as passion, strawberry, and grape vines if not well-supported. Planting wind breakers is recommended to minimize effects of strong winds.
The soil pH determines the availability of nutrients in the soil. Nutrients are most available in slightly acidic to neutral pH (a pH range of 5.5 – 7.5). Acidic soils (with a pH below 4) and alkaline soils (with a pH above 8) are notfavorable for fruit farming.
The presence of salts in the soil lowers the plants ability to take in water which results to poor growth rate and production.
To determine the pH for your soil, soil testing is recommended. Oxfarm Ltd will be willing to offer soil testing services and even adjust the pH to the required levels.
Extremely high or low temperatures can impact the lifespan and growth of plants negatively. High temperatures can negatively affect the permeability of plant membranes while low temperatures can minimize the rate of uptake of nutrients and water.
Plants require enough water for optimum growth. Too little water can cause desiccation while too much water can lead to swelling and bursting of cells.
Nutrients enhance the growth and production of fruit trees. Nutrient deficiency results to stunted growth, yellowing of leaves, and poor flowering and fruiting. If not corrected in time, the trees will just be unproductive.
Biotic and abiotic stressors can result to catastrophic losses. When they occur together, abiotic stressors can have devastating effects and can ruin your entire fruit farming investment.