Leafy Vegetables Grower's Tips

  • How to reduce the stress of heat and rain for leafy vegetables?
  • Climate change has become a major threat and consequently created large problem for the leafy vegetable growers. Water limitation and extreme weather (hot sun and frequent rain) is a severe risk that reduce productivity.
  • Various stress such as under watering, extreme heat and drought stress damage many cellular constituents such as carbohydrates, lipids, nucleic acids, and proteins, ultimately retarding plant growth, respiration, and photosynthesis.
  • Various natural products or biostimulants that should increase plant resilience to abiotic stress has been widely explored by leafy vegetable growers. Of all sources of biostimulants, those manufactured from inter-tidal seaweeds are perhaps the best studied with various modes of action being proposed.
  • Particularly, inter-tidal seaweeds are frequently exposed to unfavorable conditions including extreme variations in temperature, salinity, and light produce stress-related compounds that are essential for their survival in these environments. As such, selected seaweed resources are important sources of plant biostimulants and are widely used to promote agricultural productivity.
  • A selected inter-tidal seaweed Ascophyllum nodosum has been demonstrated to improve plant growth, mitigate some abiotic and biotic stresses while also improving plant defences by the regulation of molecular, physiological, and biochemical processes.
  • *MODIFY A NEW DIAGRAM AS THIS
  • Solution:
    • ALMINO; contains selected seaweed extracts from Ascophyllum nodosum aimed to fighting a variety of environmental stresses that limit plants growth and productivity.
    • For leafy vegetable growing, both physical and physiological stress either from hot weather, wet season, and drought will negatively impact plant physiology and thereby crop productivity.
    • Several studies of ALMINO clearly demonstrated that the application of ALMINO alleviated plant stress. The bioactive compounds present in ALMINO when applied to stressed plants have reduced the negative effects of stress by regulating a series of sequential molecular, cellular, and physiological responses including the modulation of several genes, resulting in an an improved antioxidant system and enhanced gaseous exchange through stomatal regulation.
    • ALMINO also showed significant improvement on the plants that affected by plant diseases. Such plant diseases are caused by pathogens such as bacteria, fungi, and viruses. Plants have evolved several defence mechanisms in order to fight this pathogen infection. Two types of disease resistance mechanisms in plants have been reported: systemic acquired resistance (SAR) and induced systemic resistance (ISR). ALMINO have also been reported for their ability to induce SAR and ISR against various plant pathogens.
  • How to differentiate Iron and Magnesium deficiency on leafy vegetables?
  • How to spot an iron deficiency in plants; If young immature leaves are turning pale, yellowing between the leaf veins there might be a lack of iron in the soil. This can happen when plants need more iron than the soil has to offer. As iron deficiency continues the leaf colors will fade until completely yellowing.
  • The symptoms of iron deficiency can look similar to other deficiencies, especially magnesium. In the case of magnesium, symptoms are also uniform interveinal chlorosis, however lower/mature leaves are affected not immature leaves. This is because magnesium is phloem mobile.
  • Iron is important for allowing plants to harness the energy of the sun (photosynthesis). Iron can be unavailable to plant roots in high pH or alkaline conditions. Unlike other macronutrients, iron is relatively phloem immobile. This means that once iron is taken up by the plant and deposited in leaves, it can no longer be moved around within the plant. Because of this, if iron becomes unavailable, the new leaves will first exhibit the symptoms.
  • Solution:
    • First verify that there is sufficient iron in your fertilizer program and correct the soil and water pH.
    • Use Iron supply (and other trace elements) in chelated form which keeps the iron stable (reduces oxidation/precipitation) at higher pH. The most commonly used chelating agents are EDTA and DTPA.
    • For non-EDTA iron, it becomes low available when pH close to above s6.5. For EDTA at pH > 6.5-7.0 about half the iron is still available and by pH 7.0-7.5 very little iron is available.
    • TRACEION 5Fe/2.5Zn/2.5Mn/0.5Cu/1B/3Mgo/0.05Mo; a micronutrient water soluble fertilizer designed for irrigation and foliar application. Among the benefits are following:
      • Highly concentrated with emphasis on iron as preventive and curative treatment.
      • Chelated for better availability.
      • Free flowing and fully soluble.
      • High quality and safe to be used.
  •  There is no fruit on leafy vegetable, do I still need to apply Calcium?
  • Calcium is essential for proper leafy vegetable development. Plants absorb calcium both through their roots from nutrient solutions and through leaves and shoots during foliar applications.
  • Calcium serves several important purposes within leafy vegetables. Strong cell walls require calcium to be incorporated in their structure, with adequate supplies leading to well-formed and healthy leaves. Several biological processes also employ calcium as a signaling molecule, keeping plant responding to changing environments.
  • In leafy vegetables, calcium deficiency often manifests as tip burn on developing leaves, soft leaf, and short shelf life. Especially for tip burn, it gives leaf margins a burned or crinkled appearance and will affect their appearance. The damage continues to affect new leaves and can go on to become necrotic.
  • Identifying the cause of calcium deficiency in leafy vegetables can be a tricky topic, as it is not always caused by a lack of applied calcium fertilizer. Since water carries calcium through the plant as transpiration occurs, calcium movement is dependent solely on transpiration rates. It will not matter how much calcium you supply to the root zone of your crop if you are growing in a humid and low-transpiration environment. Conversely, overly dry conditions causing plants to close their stomates and cease transpiration may also lead to calcium deficiency.
  • Solution:
    • To manage calcium deficiency, first relies on identifying the cause. Step one is looking at the fertilizer used. Is there sufficient calcium supply? Next, look at the environmental conditions, such as appropriate watering, planting density, ventilation/airflow is essential. Lastly consider complement Calcium with various mode such as soil application and foliar application.
      • CALBOR: Foliar application + fast soluble & available = supply calcium to whole part of plant, especially young and new leaves.
      • NICALBOR: Soil application + fast soluble & available = supply calcium to whole plant to supply required calcium and strengthen the plant.

4. Which form of Nitrogen is the best leafy vegetables? Is NO3-N or NH4-N?

  • Nitrogen (N) availability is a major factor determining plant growth and productivity. Plants acquire inorganic N from the soil, mainly in the form of nitrate NO3-N and ammonium NH4-N.
  • Nitrates easily dissolve in water and soil, therefore rainfall will wash nitrates downward into soil profile where they may be lost through leaching and is the major cause of nitrogen loss from coarse-textured sandy soils.
  • Although water-soluble, ammonium attaches to clay and organic matter particles, thus preventing it from leaching away. Then soil microorganisms convert the ammonium to nitrate, which is the main form taken up by plants.
  • Nitrate Nitrogen is most preferred by plants but it can be leached and lost to the atmosphere through gaseous loss. Similarly to nitrates, ammonium can be lost from the soil via gaseous loss; however it is less prone to leaching because of its positive charge. This enables it to be held in the soil.
  • Solution:
    • Mixtures of nitrate and ammonium are beneficial in terms of plant growth, as compared to nitrate or ammonium alone, and therefore synergistic responses to both N sources are predicted at different steps. Therefore, the ratio between these two forms of nitrogen is highly significance, and affects both the plants and the soil.
    • NIFOSK Series; all NIFOSK series of compound fertilizers are welly created with right combination of Nitrogen type of nitrate and ammonium.
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