Since the 80s of the 20th century, some places in China began to introduce reticulated melons, reticulated melons with their simple and elegant appearance and sweet and soft taste, quickly gained a firm foothold in the high-end fruit "family". With the help of the favorable policy of planting industry restructuring, the agricultural scientific research and technology extension departments in various localities have carried out germplasm innovation among many varieties based on the characteristics of the local climate, and screened out a series of varieties suitable for local planting.
With the improvement of varieties and the progress of cultivation technology, the planting area of reticulated melon continues to expand, and the sales income of high-grade reticulated melon is more than 60,000 mu, and the economic benefits are very considerable. Increasing the reticulated density of the fruit is an important means to improve the commodity rate of reticulated melon.
1. Biological characteristics of reticulated melon.
Reticulated melon (Cucumismelovar.)Reticulatus) is a variant of the Pachyderma subspecies, native to Africa, widely cultivated around the world, and is one of the top ten fruits in the world.
The flesh of reticulated melon is of high quality, rich in nutrition, with a sugar content of more than 16%, the color of the flesh is often orange-red or light green, the flesh is thick and solid, the texture is fine and soft, the fruit is rich, sweet but not greasy, and has the effects of clearing heat and relieving heat, diuretic and thirst-quenching, etc., which is deeply loved by consumers. At the same time, because it has a round shape, dense reticulation, beautiful and unique, and a strong three-dimensional appearance, it is like an art treasure, which is pleasing to the eye and can't bear to let go. The dense and uniform reticulation not only enhances the ornamentality of the fruit, but also greatly improves its commodity value, and the sales of reticulated melons (Fig. 1) have been high by the market.
High quality reticulated melon.
2. The formation and development of reticulation.
Previous studies have found that in the process of fruit development, due to the imbalance between the growth of the internal pulp tissue and the outer dry peel, the expansion of the internal pulp tissue causes great pressure on the external peel, forcing the exocarp to crack, and the fruit produces a large number of epidermal cells to repair the wound under the mechanism of self-healing, and with the continuous proliferation of epidermal cells, a large number of embolization cells are produced at the cracks, and the callus is finally corked and protrudes on the surface of the pericarp to form a reticulation.
High-density reticulation.
Regarding the aesthetics of reticulation, many scholars have defined or evaluated. Marc et al. used an exponent to express the density of reticulation, and the index was divided into 5 grades, with the number of mesh in the 1st index being small and the number of mesh in the 5th index being large. Sun Xiaofa et al. believe that the number of nets per 9 cm peel area = 50, and the height of the reticulated convex = 0At 6 mm, such a fruit has a more beautiful appearance and is of a higher grade. The author believes that these views are only based on geometric effects, aesthetic levels, and personal preferences, and do not form a unified theoretical basis. However, it is of great significance to grasp the characteristics of the formation and development of reticulation and the social psychology of the public's understanding of reticulation, so as to better study the influence of cultivation methods on the formation of reticulation.
Wang Huaisong et al.'s study on the reticulation development of Zhongmi No. 2 melon variety found that 20 days after pollination, cracks began to appear on the surface of the fruit, most of the middle of the fruit were longitudinal cracks, and most of the navel and fruit stalk were transverse cracks, and the transverse cracks were more than the longitudinal cracksThirty days after pollination, the longitudinal and transverse cracks form a network connection;At 35 days after pollination, most of the fruits were reticulated on the surface, and the density index reached an average of grade 440 days after pollination, all the reticulation was formed, the reticulation thickness continued to increase, and the reticulation gradually raised. In terms of the number of meshes measured in the epidermal area (3 cm 3 cm), the average number of meshes was 23 at 25 days after pollination5, and after 30 days of pollination, the average number of meshes is more than 30, and the scale of reticulation has begun to take shape. Guan Xueyu's research on the development process of reticulation divides the formation of reticulation into five developmental stages, and the development process discussed is basically consistent with the observation of the former.
3. The influence of cultivation methods on the formation of reticulation.
In the long-term evolution process, the reticulated melon has formed its unique genetic characteristics, and the genetic factors determine the external appearance of the reticulated formation, but the development of reticulated melon is also closely related to the cultivation method.
Watering. Since the origin of reticulated melon is in hot and arid Africa, the amount of watering plays an important role in the formation and development of reticulation, Wang Huaisong et al. found that the amount of watering within 20 to 40 days after pollination has the greatest impact on the formation of reticulation, and if the watering amount is too large, the cracks will become coarse, which will affect the beauty of the fruit. Therefore, watering should be controlled at this stage of production to prevent fruit cracking. Li Shengli et al. used substrate bag culture and soil general cultivation as a comparison, and observed that the reticulation formed by the substrate bag culture method was smaller, denser and evenly distributed than that formed by the soil ordinary cultivation method, and the reason for this was that the substrate bag culture method could effectively control the amount of watering.
Graft. Chen Youyuan et al. used black-seeded pumpkin as rootstock to graft Chunli reticulated melon varieties, and the fruit reticulated density was small, with an index of 1;The Chunli cultivar, grafted with Shintosa 1 as a rootstock, produced a fruit with a high reticulated density index of 4. Xu Chuanqiang et al. found that the fruit reticulation density of grafted seedlings was smaller than that of self-rooted seedlings. However, Wang Yuhong used different rootstocks to graft Napoli melon varieties, and found that the melons grafted with different rootstocks had no effect on the reticulated density. From the comparative analysis of the research results of the above scholars, the author believes that grafting has an impact on the density of reticulated grains based on his own experimental observations for many years, but the degree of influence should be analyzed according to different anvil combinations, and cannot be generalized.
But in any case, the effect of grafting on the growth of crops is obvious, and grafting technology has been widely used in the production of melons and vegetables. Previous studies have shown that grafting can not only prevent the occurrence of Fusarium wilt and promote early maturity, but also improve the yield and the ability of plants to resist low temperatures. Crop grafting should first ensure the survival rate of grafted seedlings, and it is particularly important to select suitable rootstocks for different reticulated melon varieties. After years of observation and research, the author prefers to use black-seeded pumpkin as rootstock, which has good production performance in terms of yield and quality, as well as reticulated density.
Fruit set. Wang Yuhong et al. studied the effect of fruit setting on the density of reticulation of Napoli melon varieties, and believed that compared with the 13th and 15th nodes of spring cultivation and the 12th and 14th nodes of autumn cultivation, the reticulated density was larger, the reticulated pattern was more complete, and the fruit shape was better.
In addition, Wang Yuhong et al. also studied the effects of different cultivation methods and different pruning methods on the reticulation formation of Napoli melon, and believed that the density of reticulation in the fruit produced by vertical cultivation was higher than that of climbing cultivationThe pruning method of double vine with 1 plant and 1 fruit was higher than that of single vine with 1 plant and 1 fruit.
Fourth, the method of increasing the density of the reticulation.
To understand the characteristics of reticulation formation and the influence of cultivation environment on reticulation formation, the author proposes the following methods to increase the density of reticulation based on years of experimental observation.
Manage your moisture.
7 10 days after pollination, melons and fruits develop rapidly, entering a period of rapid expansion, at this time the plant needs a lot of water and nutrients, should be watered and watered frequently;14 20 days after pollination, when the fruit develops into the peel hardening stage, that is, the fruit surface begins to form a reticulum, at this time, it should be watered in time and the amount of water should be controlled to prevent the fruit surface from drying out and cracking due to soil dryness. In the 5 7 days before the formation of the reticulation, the accumulation of nutrients in the crop is rapid, and the growth potential of the fruit is uneven inside and outsideWhen the reticulation is completely formed, if the watering is not timely, the soil is too dry, and the fruit surface is easy to form very fine reticulation or incomplete reticulation.
Do a good job of moisture management to form a high-density reticulation.
Control the sitting melon section.
Due to the few leaves on the upper part of the melon, the photosynthesis intensity is low, resulting in the small size of the plant, the fruit surface is difficult to form a reticulum, and the sugar content of the fruit is also low. The melon sitting in the middle node has strong growth potential, the fruit is large and uniform, the sugar content is high, and the reticulation formed is also more beautiful. Therefore, it is necessary to pay attention to the selection of the middle or close to the middle of the melon node. According to the experimental practice, the suitable node position of retained melon in solar greenhouse is 10 13 knots.
Control the sitting melon node position, and the reticulation density is higher.
Avoid direct exposure to bright light.
During the critical period of reticulation formation, if the fruit is directly irradiated by strong sunlight, the fruit surface is prone to incomplete reticulation. At this stage, direct exposure to strong light should be avoided, and the fruit should be wrapped in a paper bag during the reticulation period and before the reticulation is fully formed, and the paper bag should be removed 7 to 10 days before harvest.
Pay attention to fertilization and increase calcium fertilizer.
Fertilization should run through the entire growth process of reticulated melon, and timely topdressing should be carried out during the critical period of plant growth. Before planting, apply sufficient basal fertilizer, apply 5000 8000 kg of decomposed organic fertilizer per mu, 50 kg of three-element compound fertilizer with nitrogen, phosphorus and potassium content of 15, and 150 200 kg of cake fertilizer. In addition, Tan Youcan and others observed that reticulated melons like calcium fertilizer, if the plant is not sufficient calcium fertilizer for a long time, the surface of the fruit is rough and white, so it is necessary to increase calcium fertilizer appropriately. Later, in the early stage of vine extension, the early stage of fruit expansion (young fruit such as the size of an egg), the reticulated formation period of top dressing 3 times, each time the top dressing of nitrogen, phosphorus, potassium content of 15% of the three-element compound fertilizer 15 20 kg, vine extension period and fruit expansion period can be sprayed foliar fertilizer, you can choose 03% potassium phosphate dihydrogen phosphate or 500 times of Nongbaozan organic liquid fertilizer No. 6 should be sprayed to the back of melon leaves.
Advocate the application of well-decomposed organic fertilizer as base fertilizer.
Plant adjustments. Generally, the single vine pruning method is mostly used, and when the vine grows to 30 or 40 cm, the vine should be hung and pollinated manually. When the fruit sets for 5 10 days, it is necessary to choose young melons with large fruits, fruit shapes and circumferences, and slightly longer at both ends, leaving only 1 melon per plant, and when the melon grows to 250 300 grams, it should be hung in time.
Reticulated melon trellis is cultivated and hanging vines bear fruit.
Timely control of pests and diseases.
If the pests and diseases are serious during the reticulation period, the plant growth is weak, which will cause the fruit surface to be unable to form reticulation or sparse reticulation. From the pollination period to the formation of reticulation, there are 4 critical periods of medication. The first dose was administered 1 day before flowering and pollination;The second medication was applied 1 day before pouring the puffed melon water after the pollination of the reticulated melonThe third dose is in the early stage of reticulation;The fourth dose is given after the reticulation is fully formed. The main pests and diseases of the control are downy mildew, vine blight, powdery mildew, aphids, spotted submarine flies, etc., and timely spraying fungicides (such as Dasheng M-45, Pulik, DuPont Kelu, fungus poison, etc.), insecticides (such as aphid lice, Hisun insecticide, Nongdile, etc.), so that the plants grow robustly, form a beautiful reticulation, and improve the quality of fruit products. Winter Farming Meeting