Bagged pears have good quality, and managing them well after bag removal is key

In recent years, pear bagging technology has developed rapidly and has played an important role in improving pear fruit quality and economic returns. However, in production, a small number of bagged pear orchards have not achieved the expected results, mainly because the timing of bag removal is not accurately determined and management after bag removal is neglected, rather than poor management before and during bagging. In view of this, bag removal and post-removal management should be strengthened.

Timely bag removal: the time to remove fruit bags should be determined according to variety and climatic conditions. In order to prevent obvious fruit dots on the fruit surface, sunburn, fruit dehydration, fruit surface contamination and fruit surface bruising, for varieties that do not need coloring during the fruit ripening period, bags are generally not removed before harvest; instead, the fruit is harvested together with the bags after ripening, and the bags are removed during grading, so the peel is tender and not rough. For red-skinned pears and brown-skinned pears whose fruit needs coloring during the ripening period, the bags should be removed in two stages before harvest. First, 15-20 days before harvest, remove the outer bag of the double-layer bag so that the fruit inside the bag quickly adapts to strong light and other external conditions and sunburn is prevented. When the fruit will no longer be scalded, remove the inner bag. Red-skinned pears whose inner bags have been removed will quickly turn red; even brown-skinned pear varieties such as Huanghua pear, Qingxiang pear and Fengshui pear will quickly change from brown to red. Bag removal should be scheduled on sunny days from 10 a.m. to 4 p.m. Remove fruit bags on the east and north sides of the canopy in the morning and on the south and west sides in the afternoon; this can reduce the occurrence of sunburn. When removing bags, hold the fruit with one hand and untie the binding wire at the bag opening with the other to prevent the fruit from falling.

Leaf removal: removing leaves that block sunlight from reaching the fruit can increase light intensity, thereby promoting fruit surface coloring and even coloring, and increasing the content of soluble sugars in the fruit. For red-skinned pear varieties and brown-skinned pear varieties that need coloring and require bag removal before harvest, remove leaves from the 6th to the 7th day after bag removal. Focus on removing part of the leaves on upright branches on the back in the middle and upper parts of the canopy, vigorous water sprouts in the inner canopy, and competitive branches, as well as leaves directly covering the fruit and blocking light. It is appropriate to remove about 15%% of the leaves of the whole plant. To prevent excessive leaf removal, leaf turning can also be partly used; before harvest, turn leaves that directly block the fruit surface to the side or back of the fruit so that they no longer block sunlight from the fruit surface. When removing leaves, they can be cut off with scissors, but care should be taken to retain the petiole so as not to affect the development of young buds.

Fruit turning means changing the direction of the naturally shaded side of the fruit. Its effect is similar to leaf removal: to promote fruit surface coloring, especially even coloring. It can generally increase the fruit coloring index by about 20%%. Turn the fruit from the 6th to the 7th day after bag removal, preferably in the early morning or evening; do not turn fruit at noon when the temperature is high. When turning fruit, fix the fruit to an adjacent branch with transparent tape, and be careful to support the fruit with your hand and gently move it in the same direction; never rotate it back and forth, so as to avoid fruit drop. After the first fruit turning, turn it once every 5-6 days, for 2-3 times in succession.

Laying reflective film after bag removal can increase the reflected light from the ground to the canopy in the orchard and increase the sugar content of the fruit. 15-20 days before fruit harvest, after leveling the tree basin, promptly lay plastic film coated with silver powder and with a strong reflective effect under the canopy, align the outer edge of the film with the outer edge of the canopy, and press it down firmly at multiple points with bricks, stones and clods of soil to prevent it from being blown away by the wind. Each mu of pear orchard needs about 360 square meters of reflective film.