<h1 class="pgc-h-arrow-right" data-track="1" > (1) germination period</h1>
It takes about 10 days from sowing to the time the cotyledons flatten the true leaves are revealed, mainly relying on the nutrients stored in the seeds themselves, and the growth amount is small. The temperature at which melon seeds germinate is 25 to 35 °C, the optimal temperature is 30 °C, and it cannot germinate at 15 °C (some varieties are 12 °C). After the seedlings are unearthed, it is easy to elongate the hypocotyl to form seedlings under the condition of high temperature and high humidity, so when the seedlings are unearthed in cultivation, the temperature and humidity must be strictly controlled to prevent the growth of young shoots.
<h1 class="pgc-h-arrow-right" data-track="22" > (ii) seedling stage</h1>
From the flattening of the cotyledons and the exposure of the true leaves to the appearance of the fifth true leaf, it takes about 20 to 25 days, this period is dominated by leaf and root growth, although the growth amount is small, but this stage is the key period of flower bud differentiation and seedling form formation. The flower bud differentiation begins after the first true leaf is unfolded, the 2 to 4 true leaf period is the vigorous period of flower bud differentiation, and the main vine can differentiate more than 20 nodes by the first appearance of the fifth true leaf. One plant can differentiate 138 young leaves, 27 lateral vine primordial groups, and more than 100 flower primordial groups. The flowers, leaves and side branches related to cultivation have been differentiated, and the structure of the seedling body has been preliminarily established. Therefore, the quality of management in this period is good or bad for the morning and evening of flowering and fruit setting in the future,
The quality of both flower and fruit development has a great influence. Under the conditions of 30 °C during the day, 15 to 18 °C at night, and 12 hours of sunshine, the flower buds differentiate early, and the female flower nodes are low and of high quality.
<h1 class="pgc-h-arrow-right" data-track="23" > (3) elongation period</h1>
From the appearance of the fifth true leaf to the opening of the first female flower, it takes about 20 to 25 days. At this stage, the root system rapidly expands in the direction of depth, and the absorption capacity is enhanced; The growth of stems and leaves increases rapidly, and the side vines continue to occur and elongate rapidly; The leaves are increasing, the leaf area is rapidly expanding, and the photosynthetic capacity is enhanced. The vigorous growth of these vegetative organs of rhizomes and leaves, the enhancement of absorption function and photosynthetic ability, prompts the plant to enter a vigorous growth stage.
During the elongation stage, the young flowers continue to divide cells and grow up, so it is an important period for field management. In order to prevent the growth of nutrients from being too vigorous and affecting flowering and fruit setting, plant adjustment should be carried out in time at this stage, the growth of stems and leaves should be moderately regulated, and the fertilizer water should be properly controlled, so as to promote the robust growth of offspring vines, but not to cause the stems and leaves to grow.
<h1 class="pgc-h-arrow-right" data-track="24" > (iv) melon period</h1>
From the flowering of the female flower at the melon site to the maturity of the fruit, it generally takes about 20 to 40 days for early maturing varieties and 50 to 60 days for medium and late maturing varieties. According to the changes in the morphology and anatomy of melon fruit development, the development process includes fruit cell division growth period (ovary development period), fruit expansion growth period and fruit maturity stage, the initial development is the increase in the number of peel and placenta tissue cells, and then the expansion of the cell volume. The size of the melon fruit is mainly determined by the number of cells and cell volume of the fruit, and the fruit size is positively correlated with the cell size. In addition to the genetic factors related to the melon itself, the changes of these factors are also affected by many internal and external factors. Before and after flowering, cell division is vigorous, the growth and development of the ovary wall is mainly carried out through cell division, and after pollination, the growth and development of the fruit is mainly the increase of cell volume. In the late stage of fruit expansion (usually reaching the harvest period), the seeds are rapidly developed
Breeding, first the formation of the seed coat, followed by the enrichment of the embryo. According to the reproductive characteristics of different stages of fruit development, the melon stage is divided into three stages.
<h1 class="pgc-h-arrow-right" data-track="25" > (5) fruit setting</h1>
It takes about 8 to 10 days from the time the female flowers bloom to the young fruit to the size of the egg. It is a period when the plant begins to transition from vegetative growth to reproductive growth, and the growth advantage of the fruit is gradually formed. At this time, the corolla falls off, the fur on the fruit surface begins to fade (that is, hair loss), the fruit droops due to the increase in weight, the fruit stalk is bent (that is, the twisted handle), which marks that the young fruit has been basically seated and is no longer easy to fall off (that is, the melon), the ovary cells of the melon female flower before and after the opening of the ovary cells divide sharply, and enter the cell expansion stage 5 to 7 days after flowering. At this time, although the volume and weight of young fruits do not increase much, the quality of management is not only related to whether it can set fruit in time and avoid falling flowers and fruits, but also has a great impact on the development of fruits.
<h1 class="pgc-h-arrow-right" data-track="26" > (vi) puffed melon stage</h1>
The fruit rapidly expands to stop expanding. The length of this period varies depending on the variety, and thin-skinned melons take about 10 to 20 days. At this time, the total growth of the plant reaches the maximum, and the daily growth reaches the highest value. The growth of the plant is mainly based on the growth of the fruit, which is the fastest growing period of the fruit, and the weight is increased by 50 to 150 grams per day. The growth of roots, stems and leaves is significantly reduced. During this period, the pulp cells expand rapidly, and nutrients are continuously transported to the fruit. Therefore, the middle of the results is a critical period for determining the yield of the fruit. Fertilizer management needs to be strengthened in cultivation to prevent premature plant aging.
<h1 class="pgc-h-arrow-right" data-track="27" > (vii) maturation period</h1>
The fruit stops expanding to maturity. Early maturing varieties take about 10 to 14 days. At this time, the growth of the rhizome of the plant tends to stop, and the fruit volume increases very little, but the weight of the fruit still increases. This period is mainly the transformation of a large number of substances in the pulp, the peel fully shows the mature color, the flesh becomes sweet and fragrant, the flesh turns from tight to crunchy, and the seeds are full and completely colored. To improve the fruit
Solid quality, production often take measures such as controlling watering, strengthening drainage, turning melons and cushioning melons, and preventing and controlling pests and diseases.
Early maturing varieties, the growth and ripening of the fruit in the later stages are carried out at the same time; The fruit of the late ripening variety is too long, and then the material transformation of the ripening process begins, and there is a phenomenon of post-ripening, so the fruit develops for a long time. The fruiting period of large-fruit varieties requires a larger temperature difference between day and night; When the temperature difference is small, even if it can ripen, the sugar content of the fruit will be significantly reduced.
The increase in fruit volume is mainly longitudinal growth at first, and then turns to lateral growth after a certain stage. therefore. If the expansion of the fruit in the later stage is affected by environmental factors or the nodal position and nutrient area of the melon, the shape is always longer. The result period was better than the daily temperature of 27~30 °C, the night temperature of 15~18 °C, and the temperature difference of 13 °C or more; At the same time, sufficient sunshine is required. The whole branch is reasonable, the water and fertilizer management is appropriate, and the temperature difference is small, and good quality fruits can be obtained.
Melon cultivation techniques