Among crops, dicotyledonous plants generally contain more boron than monocotyledonous plants. Boron content in monocotyledonous plants ranges from 2-11 mg/kg, while dicotyledonous plants range from 8-95 mg/kg. Generally require a lot of boron crops and boron-sensitive crops, there will be boron deficiency situation, and different varieties of crops, there will be different degrees of boron deficiency symptoms: the growth of the top bud is inhibited, gradually die, lateral bud germination, weak branches clumped, root dysplasia; The leaves become thick, brittle and wrinkled, and the leaf shape shrinks. Stems and petioles are short, broken, woody, with water-like spots or chain protrusions; The succulent roots are brown, necrotic and broken. The differentiation and development of the reproductive organs are hindered, which is easy to cause the buds to fail to flower or bloom. Here are some common crop signs of boron deficiency.
(1) There are no obvious signs in the early stage of large and wheat, in the flowering stage, due to the lack of boron, the development of stamens is delayed, anther atrophy, pollen reduction or deformation, resulting in the inability of ovary to fertilize, empty and shrivel ears, resulting in “sterility”.
(2) The upper leaves of cotton plant were folded, and the lower leaves were thickened and fragile; The plant is densely clustered, the petiole has a dark green ring, severe boron deficiency, “bud but not flower”. The young buds fall off easily, sometimes due to poor fertilization, the young bolls fall off easily or the boll body is small and forms a deformity.
(3) The leaves were curled and the mesophyll became coarse; Between the veins and veins, there is a purple spot that gradually turns brown and then shrinks. The growth point dies, the stem and petiole break, and the tissue outside the root becomes swollen and brittle. Flower buds ablative, stigma of pistil raised, main inflorescence atrophy, lateral inflorescence. Long flowering time, less flowering, less flowering.
(4) The bean sprouts are dried up, and the leaves become coarse and thick. Growth is severely stunted and shortened. The main root tip was withered and the lateral root number was less and shorter. Do not open or not open, can not form normal pods, can not form abnormal nodules.
(5) When fruit trees such as citrus, apples, peaches, pears, etc. lack boron, their fruits become hard and deformed, called shrink fruit or pomegranate; When the grape lacks boron, the ear twists and forms a large number of seedless fruits in the fruit, which is called “small grain disease”.
In addition, sugar beet heart rot, celery stem crack, tobacco top rot, peanut kernel, etc., are due to boron deficiency.