Boron & fruit blossom: Macro-nutrients as well micronutrients are of primary importance in our agriculture system but due to unawareness of our farmers about importance of applying micronutrients to soils which are becoming deficient in micronutrients.
Boron is one of those micronutrients which are rapidly being deficient in soils. Boron element is different from nitrogen, phosphorus and potassium element, the amount is small, but it is also irreplaceable, it is not only the key trace element related to the fruit tree flowering and bearing, but also affects all kinds of life activities of the fruit tree.
Internal necrosis is an emerging physiological anomaly of developing fruits due to boron deficiency which may also lead to fruit cracking. The total B concentration in soils is in the range of 20 – 200 mg/kg dry weight, most of which is inaccessible to plants. The available, hot water soluble fraction in soils adequately supplied with B ranges from 0.5 – 2.0 mg B/L
1. Boron element. Trace element must be added in the flowering period of fruit trees.
Studies have shown that, in the case of boron deficiency, if the nutrient growth stage of the fruit tree, the influence on the growth of the fruit tree is not obvious, if the boron deficiency in the reproductive growth stage, it will directly affect the flowering quality, reduce the fruit setting rate, and eventually will lead to fruit tree production.
Visual symptoms of Boron deficiency generally become evident in dicots, corn and wheat at tissue concentrations of less than 20-30, 10-20 and 10 mg kg-1 weight, respectively. Nutritional disorders attributed to Boron deficiency are also prevalent among vegetables, fruit and nut trees.
2. How does boron affect the fruit tree?
Boron has an obvious effect on the pollen germination and pollen tube growth of fruit trees. If boron is absent, the pollen grain activity will be significantly reduced, and the pollen tube growth will be inhibited. In addition to this effect, boron also has an effect on fruit quality. Plants respond to decreasing B supply in soil solutions by slowing down or ceasing growth.
Boron deficiency inhibits root elongation through limiting cell enlargement and cell division in the growing zone of root tips. In the case of severe B deficiency, the root cap, quiescent centre and protoderm of root tips disappear and root growth ceases, leading to the death of root tips.
Although vascular bundles are weakly developed in B-deficient roots, early effects of B deficiency on their initiation and differentiation is poorly understood. Inhibited leaf expansion by low B indirectly decreases the photosynthetic capacity of plants.
In general, it is recommended to add boron fertilizer and the amount can be determined according to the local boron shortage by analyzing soil samples taked from pre-ploughed soil. Leaf spraying supplementary boron fertilizer is the most convenient and fast,
It is recommended that everyone in the selection of boron fertilizer, can choose high purity boron source library, the utilization rate of boron fertilizer is general boron fertilizer 8~10 times, and use more safe. In flowers, low B reduces male fertility primarily by impairing microsporogenesis and pollen tube growth.
4. When is the best time to apply boron fertilizer?
The only way to overcome the boron deficiency is its external application. Once laboratory testing has confirmed deficient boron, corrective action can be taken. Boron may be applied to the soil as a straight boron material such as borax, or it may be mixed with a fertilizer. Alternatively it can be dissolved in water and sprayed on to the crop or the soil. It can also be fed into the irrigation water.
Positive responses to B application, which provide clear evidence of B deficiency, have been reported in over 80 countries and on 132 crops over the last 60 years. Suggested to use boron fertilizer in fruit trees blossom before or at the beginning of flowering, fruit trees budding to flowering period, is the most important period of boron fertilizer application,
It also determines the success or failure of the fruit trees blossom, over the years many citrus crops, such as the bud quality is not high or flowers and general boron source library from 1000 to 1500 times the spraying is more appropriate, can be applied at trees when applying pesticide, for the first time to join.