Manganese deficiency in crops first shows that the mesophyll loses green, and the leaf veins are still green, the grass crops are parallel leaf veins, the green loss patches are elongated, the dicots are reticulated leaf veins, and the green loss patches are round. The leaf protrusions between the veins of the leaves wrinkle the edges of the leaves. In severe cases, small green patches are enlarged and connected, brown spots appear on the leaves, and even cauterization appears, and growth stops.
Zinc deficiency Crops with zinc deficiency are most susceptible to corn. The outstanding characteristics are that the plant is short, the internodes are shortened, the base of the new leaves of the seedlings becomes thin, white and brittle, translucent and then expands to the leaf margin, it is easy to tear and break when blown by the wind, and it is white and green in color, so it is also called "white flower seedling", and the leaf tips turn from red to brown when it is serious, and the whole leaf is dry and dies. When apples, citrus, pears, peaches and other fruit trees are deficient in zinc, the veins at the base of the leaves lose green, the internodes are short, the leaves are small, and the clusters are clustered, which is commonly known as "leaflet disease".
Boron deficiency Boron deficiency in crops has different symptoms for different crops, and when boron deficiency is severe, some common symptoms occur in some sensitive areas. The plant is boron deficient, the growth point is blocked, the internodes become shorter, the plant is dwarfed, the tip is wilted, and there are a large number of axillary buds, the leaves are uneven, easy to thicken and brittle, curl and atrophy, and the petiole is short and thick and even cracked. Boron deficiency makes crops have fewer and smaller flowers, reduce the seed setting rate or fruit setting rate, have a high empty shell rate, and even have the phenomenon of "flowers but not fruits". Leguminous and cruciferous plants, as well as root crops such as sugar beet, potato, and sweet potato, are sensitive to boron and require large amounts.
Iron deficiency When crops are deficient in iron, the stems, leaves, and veins lose green and yellowing (iron is immovable in the crop), and in severe cases, the whole new leaf turns yellow, and the leaf veins gradually turn yellow, and finally almost white. The old leaves also show the disease of yellowing of the leaf veins, the leaf margins or leaf tips appear scorched and necrosis, and the leaves fall off if they continue to develop, and the plant grows sluggish and dies.
Lack of copper crops, leaves are prone to lack of green, starting from the tip of the leaf, the tip of the leaf loses green, dry and curled, the symptoms of gramineous plants are basically similar, the tip of the leaf is gray-yellow, and then turns white, there are many tillers but no heading or few ears, the panicle is white, the plant is dwarf, the top is withered and the internodes are shortened like a clump of grass, and the particles are not harvested when it is severe. Fruit groves are prone to die.
Molybdenum deficiency Crop molybdenum deficiency is the most sensitive to leguminous raw fertilizer, and the general symptoms are first manifested in the old leaves, and the green loss between the veins of the leaves. Yellow-green or orange-red leaf spots are formed, and in severe cases, the stems are weak, the tips are gray, the leaf margins are curled, withered and necrosis, and then develop to new leaves, sometimes dying at the point of growth. Leguminous crops have small, pale nodules, stunted development, and delayed flowering and fruiting.
