Effect of boron on crop growth and development

Boron is not part of a variety of organisms in the crop, but it enhances some important physiological functions of the crop. Boron sufficient supply, plant lush growth, full grain, root system good, harvest protection; conversely, the lack of supply of boron, will result in serious crop production or even cut off.
Effect of boron on crop growth and development
1, cell elongation and tissue differentiation
There is a clear interaction between auxin (indole acetic acid) and boron. Boron inhibits indoleacetic oxidase activity in the root system. In the indole acetic acid stimulation, root elongation is normal. Indoleacetic acid is formed only in vascular plants in green plants and is involved in the differentiation of xylem vessels. Therefore, the general demand for boron is also limited to vascular plants. However, part of the boron plant wood weakened. Stem-forming layer cell division to strengthen, the formation of stratum cell proliferation.
2, enzyme metabolism and wood formation
The accumulation of phenolic compounds inhibits the activity of indole acetic acid oxidase. Boron can complex with phenolic compounds to overcome the inhibitory effect of phenolic compounds on indole acetic acid oxidase. Boron inhibits the activity of hydroxylase phenolic enzymes during lignin formation and xylem ductal differentiation.
3, carbohydrate transport and protein metabolism
Boron in carbohydrate metabolism has two roles: the formation of cell wall material and sugar transport. Boron can promote glucose-1-phosphate cycle and sugar conversion. Boron and calcium together play the role of "cell glue." Boron affects the synthesis of RNA, especially uracil.
The lack of boron in new leaf protein content is low, which is limited to the cytoplasm, and chloroplast protein content is not affected, so lack of boron plants green is not common. Boron can enhance crop photosynthesis, promote the formation of carbohydrates.
When the crop boron deficiency, it will cause a large accumulation of carbohydrates such as sugar and starch leaves, can not be transported to the seeds and other parts, thus affecting crop yield.
4, root growth and development
Boron can promote the normal development of vascular bundle in the roots of leguminous crops, and promote rhizobia to get sufficient supply of carbohydrates, thus enhancing the nitrogen fixation ability of leguminous crops, increasing the content of protein, increasing the fiber content of hemp crops and improving it The quality
Boron forms a complex with gluconic acid 6-phosphoglycerate in the body of the crop so that 4-phosphoglyceridic acid does not form (an important starting material for the formation of acid compounds), whereas organic acids accumulate in the root when the crop is deficient in boron Apex meristematic cell differentiation and elongation are inhibited, the occurrence of cork, causing root necrosis.
Boron can make the root tips of the crop and stem growth point equal meristem growth. Boron and alcohols, sugars and other compounds form peroxides, which improve the supply of oxygen to the roots of crops. Especially in the absence of oxygen, the application of boron fertilizer can promote crop root development. Therefore, root tubers, tubers such as sugar beet, potatoes, radish, boron fertilizer application is better.
5, crop resistance
Boron can enhance crop drought resistance and disease resistance. Boron in the body to control the role of water in the body, can improve sunflower, buckwheat and other plant protoplasm viscosity, and enhance the ability of colloidal water.
Application of boron can promote the formation of vitamin C, vitamin C can increase the plant's resistance to stress. Insufficient Boron supply to crops, reduced ability to resist stress and disease, and some physiological damage to crops.
The use of boron can greatly reduce the incidence of these diseases in these crops: "heart rot" of beet, "brown rot" of radish, "scab" of potatoes, "stalk cracking" of celery, Stem rot ", radish hollow, cabbage, poor growth of spinach, sweet potato" brown spot ", linen" blight ", sunflower" white rot "and" gray mold "beans" charcoal " Wait.
6, early crop improvement
Boron can promote crop precocity. According to domestic data, under the influence of boron, the spring wheat will be shortened by eight days for winter wheat.
Boron application in cotton increased before frost and the seed cotton yield and fiber quality increased. Corn, rice boron to make the main growth period in advance, the seeds mature about five days earlier. This accelerated precocity of boron is of particular interest, both in the cold regions of the mountains and in the two crops. Thirdly, the development of agricultural production in some areas has some positive significance.
Rape boron can reduce protein and increase fat content. Cucumber, tomato boron can increase the vitamin C content. Apple, citrus boron can increase the sugar content, reduce acid content.
The application of boron fertilizer in hybrid seed production can make the reproductive organs of both parent and maternal plants reach the same maturation stage and promote the significant increase of seed production, meanwhile increase the seed setting rate of distant hybridization.
7, pollen germination and pollen tube growth
The indirect effect of boron may be related to the increase of sugar content in nectar and the change of its composition, making the flowers of the arboreal plant more attractive to insects.
The direct role of boron and pollen anther production ability and pollen grain vitality are closely related. Boron can stimulate pollen germination, especially pollen tube elongation.
Boron can promote the normal crop reproductive organs, is conducive to flowering and fruiting. Appropriate use of boron fertilizer, can accelerate the development of floral organs, increase the number of pollen, and promote the pollen grains germination and pollen tube growth.
Rape lack of boron caused by the "flowers and not real" reasons, the results show that boron deficiency and can flowering, but can not be normal and strong development of male and female gametophyte rape, ovary structure is complete, but due to lack of attachment of boron stigma The ability of pollen, the anther wall destroyed and the ability to lose shells, pollen blocks and the development of low rate, resulting in rape can only flowering and can not be strong. This result strongly supports the importance of boron in the growth of reproductive organs.