Watermelon transplanting should avoid these seven points:
Avoid low ground temperature.
The lowest temperature condition of watermelon radicle elongation and lateral root regeneration is 65438 03℃, while the normal rooting requires 65438 08℃ ground temperature. Transplanted melon seedlings in early spring often encounter the situation that the underground 10 cm ground temperature cannot reach 15℃ and cannot take root. Transplanting should be carried out after taking measures such as film locking and spraying rooting powder. Take measures to raise ground temperature or promote roots in advance.
Second, avoid transplanting old seedlings.
The suitable age for normal transplanting of watermelon is four-leaf stage. Because of the small growth, poor adaptability and resistance to the outside world, seedling emergence is slow. However, if the seedling age is too large (more than five leaves), it will cause adverse consequences such as root injury, stem bark cork in the ground, hollow pulp and so on, thus affecting the slow seedling.
Three bogeys: the seedbed is short of water and the watering is uncomfortable.
Traditional transplanting methods often cause the root epidermis and root nutrient soil to be blocked or loose, which will seriously damage the root system. After transplanting, flooding irrigation will reduce the soil temperature and make the ridge soil dense. Pouring some water after planting will make the soil of seedling lump and ridge bed not combine well, and the gap ventilation of transplanted seedling bed will also affect the root growth.
The correct method is: control the temperature and moisture before transplanting the seedbed to keep the root system healthy and intact; After transplanting, under the condition of keeping the ground temperature, pour some water or some dark water to bridge the compact bed soil and foreign soil.
Avoid using raw manure as base fertilizer, because the soil in the base fertilizer is not evenly mixed.
After transplanting watermelon, when it comes into contact with immature organic fertilizer and high concentration chemical fertilizer, the roots will burn, which will slow down the seedling pushing or lead to seedling death. Therefore, the applied organic manure such as chicken manure, pig manure and cow dung must be fully decomposed before application, and the base fertilizer should be fully mixed with the soil in the field bed.
Five taboos ignore soil treatment
Due to the expansion of watermelon production scale and the increase of crop biological yield in recent years, the stock of pathogens and pests in the soil is also increasing. Such as Fusarium oxysporum and Colletotrichum gloeosporioides of watermelon, with the increase of ground temperature, the occurrence period of diseases and insect pests will be advanced. If we neglect the prevention and control of soil diseases and insect pests, it will also have serious consequences. In furrow cultivation, broad-spectrum fungicides such as carbendazim, thiophanate, trichlorfon and phoxim will have good effects.
Six taboos are uncomfortable.
Early-maturing watermelon cultivation often adopts measures such as buckling shed and covering with plastic film to increase temperature and keep warm. Watermelon seedlings can withstand the high temperature of 38℃ and the low temperature of 10℃ without direct contact with the plastic film in the greenhouse. If the temperature exceeds this limit, it will cause baking or chilling injury.
7. Avoid topdressing and watering prematurely.
The amount of fertilization should be determined according to the seedling situation and soil fertility. Generally, the fertilizer and water supply after delayed seedling of watermelon should be after the five-leaf stage, and appropriate amount of nitrogen and phosphorus fertilizer or foliar fertilizer should be applied after watering to promote the early development and rapid growth of watermelon. Premature supply of water and fertilizer is usually harmful.