The latest grapefruit tree cultivation techniques tutorial

Pomelo is also known as Wendan, Xiangluan, Zhuluan, Neizi, Stripe, Lei Pomelo, Luyou, Hu Gan, Stink Orange, Stink Pomelo, Throw, Bud, etc. Pomelo is the mature fruit of Rutaceae Pomelo, produced in Fujian, Jiangxi, Guangdong, Guangxi and other southern regions of China. Pomelo fragrance, sour, cool, rich in nutrition, medicinal value is very high, is one of the fruits that people like to eat, but also recognized by the medical community as the most therapeutic fruit, pomelo tea and pomelo peel also have practical value.

biological characteristics

1. Division of varieties

① Grapefruit varieties pollinated fertile, bearing multi-seeded fruit. Such as white sour pomelo, red sour pomelo, etc.

(2) Grapefruit varieties are pollinated incompatibly, the fertility rate is very low, and they can bear a few fruits with few seeds. The fruit setting rate is high only when the pollen of different varieties (strains) is pollinated, but the fruits have many seeds. Such as Shatian pomelo (white meat), Zaohe pomelo, Sangma pomelo, Jinlan pomelo, Zhaipo pomelo, Cuntou sleeve, Caijia pomelo, Shitou pomelo, Jincun pomelo, Changshou Shatian pomelo Duan pomelo, ancient money Shatian pomelo, silk pomelo, etc.

3. Pollen pollination of grapefruit varieties was sterile, parthenocarpy ability was strong, seedless fruit could be produced, but fruit setting rate was low, fruit cracking was easy, fruit setting rate was significantly increased, fruit cracking was reduced, but fruit seeds were more. Such as Yuhuan flat cone round pomelo, Guanxi pomelo, Dukou pomelo, Duwei pomelo, Liangping pomelo, Yue pomelo No.5, Xishi pomelo, etc.

(4) Stamen degenerated, pollen deficient (male sterile), but parthenocarpy was strong, seedless fruit could be produced, fruit setting rate was significantly increased by cross-pollination, but fruit seeds were more. Such as hairy orange pomelo and so on

2. Growth habits

Pomelo is evergreen tree, pomelo leaves like orange, orange is mostly long oval or long oval, wing leaves are heart-shaped; fruit is mostly gourd-shaped, pear-shaped or spherical, surface yellow, orange is more, fruit surface luster has concave points, generally has irritating smell, peel is relatively thick, can be peeled by hand. Fruit is larger than citrus, single weight often up to 1 kg or more, 15-25 cm in diameter. There is a white sponge layer between the pericarp and the pulp. The flesh is red or yellow-white, white is more common, rich in juice and rich in flavor, sweet or sour, sometimes bitter, mainly due to its biological glycosides. Grapefruit can be stored in the natural environment for months without spoiling. Flesh petals for 12-15 petals, artificial cultivation often do bagging treatment to make it seedless, natural state of a single fruit seeds can reach more than 100. Usually grapefruit ripens between October and November, while early-maturing varieties can be marketed in September, and late-maturing varieties can be as late as January or February of the following year. The root system is shallow and concentrated in about 1 to 3 meters.

1. Root system. Root system distribution: the seedling tree crown is tall, the taproot is developed; the grafting tree lateral root is developed. New root growth alternates with shoot growth, so there are several peaks of root formation per year. The first rooting peak occurred after the spring shoots stopped and before the summer shoots sprouted, which was the highest rooting number in the whole year. High temperatures inhibit root growth.

2. Branch tip. Pomelo young trees grow vigorously, 1 year can pull out spring, summer, autumn, late autumn 4 shoots, large number of branches, crown expansion rapidly. 4-5 When the annual grapefruit enters the fruiting stage, the crown has a large number of fruiting parts, which is an important reason for the high yield of grapefruit in the early stage. After entering the peak fruit stage, only spring shoots are generally taken, not summer shoots. The new shoots from the beginning of spring to the beginning of summer are called spring shoots. The spring shoots are neatly concentrated, the number is large, the branches are dense, short and strong, and the length is 10-20 cm. They are the main new shoots for fruiting and creating accumulated nutrients in that year. Strong spring shoots can become the basal shoots of summer and autumn shoots, medium growth can develop into the fruiting mother shoots of the following year, and spring shoots developed from mixed buds can develop into the fruiting shoots of the current year. The quantity and quality of spring shoots depend on the nutritional status of the tree. If the nutrient accumulation of last year is sufficient, the quantity and quality of spring shoots are more and better, and the quantity and quality of spring shoots determine the quantity and quality of fruiting branches of this year and fruiting mother branches of next year. The prerequisite for high and stable yield is to cultivate spring shoots with high quantity and good quality.

3, flowering habits

Grape trees generally begin to bear fruit in 8-10 years, grafted trees bear fruit in 4-5 years, and 1-2 years after the initial fruit is entered into the peak fruit period. 5-7 Annual trifoliate orange rootstock grafted trees yield 15-50 kg, 8-10 years up to 50-100 kg.

1. Fruit mother branch. The spring shoots of grapefruit are the main fruiting mother shoots. The leaf axils of each node of the mother branch can differentiate flower buds and produce fruiting branches, and the fruiting branches produced by the top nodes are more. According to the investigation, 23.7% of the fruiting branches were extracted from the first node, and 72.7% from the first to the fourth node. The fruiting branches with several nodes at the top have large flower buds and high fruit setting rate. Therefore, fruits are mostly concentrated on the fruiting branches with a few nodes at the tip of the fruiting mother branch, and short fruiting mother branches should be avoided when pruning. The fruit bearing ability of fruit bearing mother branches of different lengths was investigated. The fruit bearing ability of fruit bearing mother branches of 10-20 cm length was the strongest, and the fruit bearing capacity accounted for 56.9% of the total.

2. Fruit branches. Grapefruit flower buds are mixed buds, sprouting in spring and flowering. The fruiting branches can be divided into four types according to morphology: inflorescence branch, leafless inflorescence branch, leafless single flower branch and leafless single flower branch. A leafy single flower branch, that is, a leafy spring shoot with a flower bud on the top, flowering a little later, high fruit rate, good fruit quality, but less quantity. Fruit setting rate of leafy fruiting branches was higher than that of leafless fruiting branches. There are many leafless fruiting branches and low fruiting rate. Strong tree vigor, leafy inflorescence branches and flowering branches more; weak tree vigor, leafless inflorescence branches more. Therefore, it is of great significance to cultivate strong tree vigor and good fruiting mother branches, strive for more leafy fruiting branches, especially more leafy single flower branches, reduce flower bud quantity and nutrient consumption, and improve fruit setting rate for achieving high and stable yield. Pomelo bore branches have strong bearing ability, and those with weak light intensity can differentiate into normal flower buds and bear fruit. This is also one of the important factors for good yield of grapefruit.

(3) flowering and fruiting. Pomelo flowers solitary or in racemes. Flowers begin in late April and flourish in early May. The fruit with seeds can be produced by pollination and fertilization of normal pistil and pistil. Pomelo also has the ability of parthenocarpy. The ovary without pollination and fertilization can also expand and develop into seedless fruit. Physiological fruit drop: grapefruit physiological fruit drop from mid-May to the end of June basically ended. Fruit drop accounts for 17.8% of total fruit drop in mid-May, 40.6% in late May, which is the peak period of physiological fruit drop. Fruit drop accounts for about 90% of total fruit and flower drop from mid-May to mid-June, and basic fruit drop results in early July. Grapefruit ripens around the beginning of winter.

3. Growth conditions

Climatic conditions. The annual average temperature of the place of origin is 17.5℃, the extreme high temperature is 40.5℃, the extreme minimum temperature is-9.2℃, the frost-free period is 238 days, the annual precipitation is 1725.3 mm, and the annual sunshine is 1898.6 hours. Grapefruit has better tolerance to low temperature than sweet orange, mandarin orange and satsuma orange.

2. Terrain and terrain. Grapefruit is not strict with terrain requirements, plains, beaches, hills, low mountains, mountains below 500 meters above sea level, slopes not exceeding 25 degrees can be planted.

(3) Pomelo is not strict with soil, soil pH value is 5.5-6.5. Alluvial soil, red yellow soil, purple sand soil, vegetable garden soil, as long as the soil layer is deep and the drainage is good, it can be planted. Sandy loam is the best soil quality.