Boron Deficiency in cereals and SugarCane crops

Boron deficiency in barley

Boron deficiency causes similar symptoms in wheat, barley, oats, and rye.

Small chlorotic spots form between the veins of the youngest unfolded leaves. The spots enlarge and coalesce to form the characteristic white stripes. The stripes do not develop on mature leaves. Leaf unfolding is likely to be delayed and abnormal. Sterility of ears occurs, probably as a result of impairment of pollen germination and growth.

Some increased tillering may be observed and internodes can be short. There are indications that boron deficient wheat and barley is more susceptible to mildew (Erysiphe graminis) than healthy plants.

Boron applications have been known to reduce the incidence of ergot (Claviceps purpurea) on barley. It is likely that infection is facilitated by the sterility of the flowers and by the open configuration of the spikelets when boron is deficient.

Boron deficiency in corn

Boron is a key element in plant nutrition. University researchers have found yield increases ranging from 9 to 37 bushels of corn per acre where boron was added. Corn requires high levels of all nutrients to ensure maximum economic yields.

Boron is necessary for:

• Stimulation of root and shoot development
• Tassel and silk formation
• Movement of sugars from leaves to ears
• Pollen germination
• Pollen tube growth and seed formation
• Better water use efficiency and drought tolerance

Irregular distribution of kernels and a general reduction in growth are the first signs of boron deficiency. Severe boron deficiency results in short bent cobs of corn with under-developed tips and very poor kernel development. Yellow or white spots develop between the veins on young leaves, and the spots often coalesce forming streaks. These streaks, which may be waxy and raised from the leaf surface, do not normally develop on fully grown leaves. The leaf tips may be curled. There is also a shortening of the internodes and often the young leaves fail to open. There are indications that high-lysine corn is more susceptible than normal corn to boron deficiency.

Boron deficiency in millet

The limited work on these species indicates that boron deficiency results in the symptoms that are common in the graminae; namely, white streaks on the young leaves and ear sterility.

Boron deficiency in oats

Boron deficiency causes similar symptoms on wheat, barley, oats, and rye.

Small chlorotic spots form between the veins of the youngest unfolded leaves. The spots enlarge and coalesce to form the characteristic white stripes. The stripes do not develop on mature leaves. Leaf unfolding is likely to be delayed and abnormal. Sterility of ears occurs, probably as a result of impairment of pollen germination and growth.

Boron applications have been known to reduce the incidence of ergot (Claviceps purpurea) on oats. It is likely that infection is facilitated by the sterility of the flowers and by the open configuration of the spikelets when boron is deficient.

Boron deficiency in rice

Boron is essential to rice growth. Without sufficient levels of this essential micronutrient, boron deficiency occurs in rice, negatively impacting both crop health and yield. However, sufficient boron in the soil has the following benefits for rice:

• Increased pollination and seed set
• Increased grain filling
• Reduced chaffiness
• Reduced bursting when cooking
• Increased uptake of macronutrients which leads to greater vigor and better use of the fertilizer for rice
• Speeds maturity
• Increased yield, quality, and income from the crop

When there is not enough boron in the soil, boron deficiency results in reduced pollen viability.

What causes boron deficiency in rice?

Boron deficiency in rice can be caused by one or more of the following:

• Very little available boron in soil
• Boron adsorption on organic matter, clay minerals, and sequioxides
• Reduction in boron mobility due to drought
• Excessive liming

The critical soil level for occurrence of boron deficiency is 0.5 mg B kg^-1.

How common is boron deficiency in rice?

Boron deficiency is not very common in rice, but can occur in the following soils:

• Highly weathered, acid red soils and sandy rice soils in China
• Acid soils derived from igneous rocks (as opposed to soils formed from marine sediments)
• High organic matter status soils in Japan

What are the symptoms of boron deficiency in rice?

In rice plants, boron is relatively immobile—it does not move throughout the plant. Because it does not move to new growth, boron deficiency symptoms usually appear first on young leaves. These leaves don’t grow properly, remaining short and narrow with faint white or yellow, rolled leaf tips.
 
The next emerging leaves are folded, bent, and almost white. If such leaves open, a large part of the blade will quickly dry up. Boron deficiency also leads to shorter plant height. When the deficiency is severe, growth stops completely, but new tillers continue to be produced. These tillers will quickly show the same symptoms and remain stunted.
 
The panicles in rice are also severely affected by boron deficiency. Rice plants may fail to produce panicles if they are boron deficient at the panicle formation stage. Roots of severely affected plants are stubby, tough, and light brown in color.

Prevent and cure nutrient deficiencies in rice

With the right fertilizer and appropriate application of boron in rice, you can prevent or correct any deficiencies. Below, you'll see our options for borate fertilizers for rice and application recommendations: 

• Granubor^® is an ideal material for dry blends that are applied broadcast preplant or sidedressed.
• Fertibor^® works best in fertilizer suspensions for preplant broadcasts, sidedressing, or band sprayed over the pre-emergent seed row.
• Solubor^® allows the most flexibility for applying boron. It can be dissolved alone in water or in liquid fertilizers and/or pesticides and then applied to the soil or directly onto the foliage.
• Apply 20 Mule Team^® borate fertilizers in soluble forms for rapid treatment of boron deficiency broadcast and incorporated before planting, topdressed, using Fertibor or Granubor or as foliar spray using Solubor during vegetative rice growth.
• For foliar application, 10g of Solubor in 15L of water is a recommended concentration of the spray solution. Solubor can be mixed with common insecticides or fungicides used in the nursery. Split the boron foliar spray into three or four applications along with the insecticidal or fungicidal spraying rounds.
• For soil application, broadcast or topdress 4-6kg of Fertibor or Granubor per hectare in one time application before planting or split on twice application half dosage before planting and half dosage at vegetative growth stage.

Boron deficiency in rye

Boron deficiency causes similar symptoms on wheat, barley, oats, and rye.

Small chlorotic spots form between the veins of the youngest unfolded leaves. The spots enlarge and coalesce to form characteristic white stripes. The stripes do not develop on mature leaves. Leaf unfolding is likely to be delayed and abnormal. Sterility of ears occurs, probably as a result of impairment of pollen germination and growth. Some increased tillering may be observed and internodes can be short.

Managing ergot infection

Ergot (Claviceps purpurea), can negatively impact the quality of small cereal and rye grain, and in turn, the profitability of the crop. A fungal parasite, the second phase of ergot development generates spores from the primary germinating sclerotia. As the spores become wind-borne and settle onto the flower of the plant, intercellular hyphae grow downward between the cells of the style and extend into the ovary. Because of the nature of spore transmission, ergot infection is most successful when the plant’s flower is fully open.

The fungus becomes increasingly prolific and difficult to manage during unseasonably cool, wet spring weather. The excessive moisture and cool weather prolong the flowering period and encourage the plant to form shallow roots.

Research supports that infection risks may be mitigated through proper micronutrient management. Boron applications have been known to reduce the incidence of ergot on barley. It is likely that infection is facilitated by the sterility of the flowers and by the open configuration of the spikelets when boron is deficient.

Boron deficiency in sorghum

Sorghum is grown for both food and forage in semi-arid and subtropical regions around the world. Fertilizing sorghum with a minimum amount of boron is crucial role for:

• Helping sugars and nutrients move from leaves to reproduction systems
• Supporting the development of plant organs
• Increasing pollination
• Increasing seed development
• Strengthening cell walls

Under normal growing conditions, boron can maximize forage yields. But, when you have high salinity soils, you may also have high concentrations of boron.

Boron deficiency symptoms include white streaks on the young leaves, narrow gray leaves with transparent stripes, and ear sterility. In addition, sorghum seed heads may not be fully filled.

Reducing boron deficiency

A recent study has shown that using 5 mg L^-1 of boron under higher salinity levels could significantly increase forage yields in terms of green and dry matter weights.* In addition, other research indicates increased yield for rain-fed crops that receive balanced fertilization.**

Before applying boron added fertilizers, take soil tests to know nutrient levels then, follow up with sorghum tissue samples in the growing season to verify root uptake by the plants.

 

* Alkhamisi, Saif, et al. (2017) Influence of Boron on Sorghum (Sorghum Bicolor L.) Forage Yield under Different Water Salinity Levels. Int J Contemp Appl Res, 4:8. 50-61.

** K. L. Sahrawat, et al. (2008) Sulfur, Boron, and Zinc Fertilization Effects on Grain and Straw Quality of Maize and Sorghum Grown in Semi-Arid Tropical Region of India, J Plant, 31:9, 1578-1584.

Boron deficiency in sugar cane

Although boron is essential to the health and quality of sugar cane, it’s often the most deficient micronutrient in sugar cane plantations. Boron plays a crucial role in a number of vital processes and is highly important for sugar cane yield.

Fertilizing sugar cane plants with adequate boron is necessary for:

• Synthesis of nucleic acids
• Metabolism of carbohydrates
• Formation of cell walls
• Transportation of sugars through the cell membranes
• Cell division
• Proper development of leaves

The first symptoms of boron deficiency appear as small, narrow watery spots developing parallel to the vascular bundles on the young leaves, resulting in a distinct striping. The lesions soon enlarge and the leaf tissue may later separate, forming a fracture with a serrated inner edge. Sugar cane leaf tips can become necrotic, apical growth is retarded, and the young leaves are small, narrow and somewhat chlorotic. Internal brownish streaks frequently develop at, and slightly below, the growing point. Young sugar cane plants are bunched with many secondary stalks. The spindle leaves turn white and dry out.

Note that “pokkah boeng,” a disease caused by Fusarium monoliforma and injury from the herbicide Dalapon, can cause symptoms similar to boron deficiency.

Boron deficiency in wheat

Boron deficiency causes similar symptoms on wheat, barley, oats, and rye.

Small chlorotic spots form between the veins of the youngest unfolded leaves. The spots enlarge and coalesce to form the characteristic white stripes. The stripes do not develop on mature leaves. Leaf unfolding is likely to be delayed and abnormal. Sterility of ears occurs, probably as a result of impairment of pollen germination and growth.

You may see some increased tillering and internodes can be short. There are indications that boron deficient wheat and barley is more susceptible to mildew (Erysiphe graminis) than healthy plants.

Boron applications have been known to reduce the incidence of ergot (Claviceps purpurea) on wheat. It is likely that infection is facilitated by the sterility of the flowers and by the open configuration of the spikelets when boron is deficient.