Causes and countermeasures of bran heart of radish in early spring

The heart of radish bran is also called hollow, that is, the hollow phenomenon occurs in the central part of the xylem of the fleshy root. 1. The causes are as follows: (1) it is related to variety. For the varieties with large parenchyma cells of fleshy roots, the density of fleshy roots is poor, and bran hearts are easy to appear. (2) related to soil quality. Turnips cultivated in sandy soil appear earlier than those cultivated in loam or clay. (3) improper water supply. During the growth period, the water was uniform in the early stage, but it was dry in the later stage, especially in the stage of fleshy root formation, the soil was short of water and the growth was blocked, resulting in the appearance of bran core. (4) the planting density is unreasonable. Under the condition of wide row spacing, the fleshy root grows too fast, and the growth of leaf and heel is out of balance, so that the organic nutrition produced in the aboveground part is not enough to meet the needs of underground fleshy root expansion, and bran heart is easy to appear. (5) fertilization is unreasonable. Especially in the later stage, the topdressing is too late, the dosage is too much, coupled with the improper collocation of fertilizer varieties and the application of too much nitrogen fertilizer, so that the aboveground growth of radish is too exuberant, and the root tuber is hypertrophic and cause bran heart. (6) the harvest is too late or early bolting has occurred. (7) the wound caused by split skin and crack in the process of harvest, storage and transportation is the enhancement of respiration, excessive consumption of nutrients and bran heart. (8) the storage temperature is too high. The suitable temperature for storage of radish is 1-3 degrees, more than 3 degrees is easy to sprout and grow and lead to the heart of radish bran. (9) dry storage environment. The ideal air humidity is 90-95%. When the radish is less than 90%, the radish is constantly dehydrated to make the tissue soft and bran. two。 Control measures: (1) choose varieties that are not easy to bran heart and have high density of fleshy roots. (2) reasonable close planting. (3) applying fertilizer scientifically. The principle of fertilizing radish in spring should be based on base fertilizer and supplemented by topdressing, and pay attention to the reasonable collocation of nitrogen, phosphorus and potassium. (4) the water supply should be uniform. To prevent the soil from being too dry and wet, keep the soil moisture at 70% Mur80%, especially in the later stage of radish growth. (5) timely harvest. (6) Chemical control, generally spraying 50mg/kg gibberellin solution (do not spray too early, so as not to restrain the expansion of fleshy root) or 10mg/kg naphthylacetic acid solution half a month before harvest, not only does not affect the growth of fleshy root, but also can prevent bran heart and delay ripening. If 5% sucrose and 5mg/kg borax solution are added when spraying 10mg/kg naphthylacetic acid, the effect of preventing bran heart is better. (7) minimize mechanical damage such as broken skin and fracture in harvesting and transportation. (8) pay attention to the temperature and humidity of temporary storage.