(1) specific reasons: if the pruning is too much and there are few branches and leaves left in the aboveground part, the aboveground and underground parts will lose balance. Furthermore, a large number of roots will die, which will lead to the overall malnutrition. In this case, it is the time of rapid growth that may cause the leaves to turn yellow.
(2) solution: apply 0.3% urea to foliar top dressing, once a week, three times in a row.
(1) specific reasons: such as "root carcinomatosis", "root knot nematode", etc., can cause yellow leaves.
(2) solution: after discovery, cut off the part suffering from diseases and insect pests in time, and then spray medicine, such as Bordeaux liquid, etc.
(1) specific reason: light is insufficient, chlorophyll cannot form, the leaf may turn yellow, also may appear thin phenomenon..
(2) solution: try to let the plants receive enough sunlight. In addition, attention should be paid to pruning to increase the transmittance.
(1) specific reasons: drought and flood may make the leaves yellow or even die.
(2) solution: when the rainfall is very small, or in the rainy season, different measures should be taken to adjust the water balance, such as watering in the early stage and draining in the later stage.
(1) specific reason: if there is too much fruit and too much load, nutrients will be insufficient, so yellow leaves will appear.
(2) solution: don't only pursue the yield, but also the flower and fruit thinning and reasonable weight bearing.
