Boron Deficiency Symptoms in Crops

In crops, the boron content of dicotyledonous plants is generally greater than that of monocotyledonous plants. The boron content of monocots is between 2-11 mg/kg, while that of dicots is between 8-95 mg/kg. Generally, crops that require a large amount of boron and crops that are sensitive to boron will suffer from boron deficiency, and different varieties of crops will have different degrees of boron deficiency symptoms: the growth of terminal buds is inhibited, gradually withered, and lateral buds germinate. Weak branches are clustered, and the root system is poorly developed; the leaves are thickened, brittle, shrunken, and the leaf shape is reduced; the stems and petioles are thick and short, broken, and woody corky, with water-soaked spots or chain-like protrusions; the fleshy roots have Brown, necrosis, and rupture; the differentiation and development of reproductive organs are hindered, which may easily cause flower buds to fail to bloom or flower to be fruitless. The following are some common manifestations of boron deficiency in crops.

(1) There are no obvious signs in the early stage of large and wheat. During the flowering stage, due to the lack of boron, the development of stamens is slow, the anthers shrink, and the pollen is reduced or deformed, resulting in the failure of fertilization of the ovary and the appearance of empty and shriveled ears, thus causing "infertility syndrome" .

(2) The upper leaves of the cotton plant are wrinkled, and the lower leaves are thickened and brittle; the plant shape is dense and multi-clustered, and there are dark green rings on the petiole. When there is severe boron deficiency, "buds do not bloom". The young buds are easy to fall off, and sometimes the young bolls are easy to fall off due to poor fertilization or the boll body is small and deformed.

(3) Rapeseed leaves are curled, and the mesophyll becomes thicker; between the veins, there are purple spots, which gradually turn brown, and then shrink. The growth point dies, the stem and petiole rupture, and the tissue outside the root is swollen and brittle. Flower buds shed, pistil stigmas raised, main inflorescence shrunken, lateral inflorescences. Long flowering time, less flowering, less flowering.

(4) The bean sprouts are dry and the leaves become thicker and thicker. Growth is severely retarded, shortened. The main root tip is withered, and the number of lateral roots is less and shorter. If it does not open or does not open, it cannot form normal pods and cannot form abnormal nodules.

(5) When fruit trees such as citrus, apple, peach, pear, etc. lack boron, the fruit becomes hard and deformed, which is called shrunken fruit or pomegranate; Known as "small grain disease".

In addition, beet heart rot, celery stem crack, tobacco top rot, peanut kernelless, etc. are all caused by boron deficiency.