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How large are the DNA differences between different breeds of dogs?
In an issue of the journal Science, researchers wrote that the genetic differences between different breeds of dogs are unusually pronounced, so much so that they can determine a dog's breed based solely on its DNA. This phenomenon is related to humans controlling inbreeding in dogs over the past 300 years to obtain different dog characteristics. This shows that humans can indeed play an important role in the field of species evolution. When researchers analyzed the DNA genetic code of dogs in an attempt to further understand the genetic factors of human diseases, they were surprised to find that, in just the past few hundred years, not
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What to do when large silkworms are forced to mature prematurely by high temperatures? Do a good job of heat prevention and cooling
(1) In hot weather, prevent mulberry leaves from wilting and overheating. When feeding the silkworms, wait until the mulberry leaves have cooled before feeding. When feeding at noon, provide appropriate supplementary water to help cool things down and delay mulberry leaf wilting. This can be combined with supplementary feeding of miecanying or xiaoteling for disinfection. The standard for supplementary feeding of miecanying is 1 milliliter of miecanying agent added to 0.5 kg of water, fed with 4-5 kg of mulberry leaves, mixed evenly and then fed to the silkworms, with supplementary feeding once every 48 hours. The standard for preparing the xiaoteling agent water solution for disease prevention is to add 25 kg of water to each packet of the main agent. First use a small amount of water to
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Detailed Introduction to the Large-Fruited Sweet Carambola No. 3 Variety
Approval number: Gui Shen Guo 2007004. Variety name: Large-Fruited Sweet Carambola No. 3. Breeding unit: Horticulture Research Institute, Guangxi Academy of Agricultural Sciences. Variety source: selected from bud-sport single plants of Malaysian B17 introduced from Hawaii. Characteristics: branches spreading, tree vigor relatively weak, small branches numerous and dense, soft and drooping. Leaves are odd-pinnate compound leaves, alternate; number of leaflets 7-13, mostly 11, alternate or opposite, 4 cm-9 cm long, 2 cm-5 cm wide; small
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Detailed introduction to the new large peach variety Hongfurong
Hongfurong giant peach is a mid-to-late ripening variety. In the Beijing area, the flowering period is in mid-to-late April, and the fruit can be picked in early August, with a whole growth period of about 110 days. It has extremely strong storage tolerance; the harvested peaches can be kept at normal temperature for 20 days without spoiling or rotting, making it most suitable for long-distance transport. The peaches are especially large, with an average fruit weight of 420 grams and a maximum of up to 1210 grams. The appearance is gorgeous; when ripe, the fruit is nearly round with a flat top, the suture line is obvious, the peach fuzz falls off naturally, and the fruit surface is pink. The flesh is milky white, dense, and hard-melting
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Detailed Explanation of Key Techniques for Transplanting Large Red Spruce (Picea koraiensis) Trees
Red spruce, also known as Tiger-tail Pine, Korean Spruce, etc., is an evergreen tree of the genus Picea in the family Pinaceae. It is native to Northeast China and Korea, and is now widely planted in the Beijing and Qingdao areas, with some distribution in the Northwest as well. This tree species has a graceful form, with a spire-shaped crown and large branches that spread horizontally or extend slightly at an angle; it is highly adaptable, with a shallow root system and well-developed lateral roots, making it relatively easy to survive after transplanting. I. Transplanting Time: Spring is the best time for transplanting large trees. Under complete technical measures, transplanting in late November and late May can both achieve a survival rate of over 98%. II. Transplanting Preparation
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High-grafting method for large-leaf privet and golden-leaf privet
Large-leaf privet (Ligustrum lucidum) and golden-leaf privet (Ligustrum × vicaryi) both belong to the Oleaceae family and the Ligustrum genus. The former is a fine sub-tree for landscaping, but because it is so common, it is often overlooked. The latter is a colored-leaf tree species that has been widely used in recent years. Because golden-leaf privet is a shrub, this limits its practicality. In order to expand the landscaping functions of both, the author used the method of high grafting to draw on each other's strengths to achieve this goal. The steps are as follows: in spring, use branch grafting or bud grafting (after the sap has begun to flow, and preferably before bud break). Use large-leaf privet with a diameter at breast height of 3 cm to 4 cm as the rootstock,
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Cultivation and Management Methods for Large Potted Azaleas
The Wuxi Azalea Garden where the author works mainly grows azaleas in pots. The garden has a number of large azaleas over fifty or sixty years old, which are quite difficult to manage. In addition, it hosts the annual azalea flower show every year, and after the show the azaleas generally resume growth about 20 days later, right when they face the extremely unfavorable hot summer for azalea growth. In order to strengthen azalea growth, we gave careful thought to the growing medium. Azaleas have shallow, fine roots and high requirements for potting soil. In the past we always used orchid soil as the growing medium for repotting. In recent years we found that the quality of some orchid soil on the market
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Key Techniques for Large-Bag Bed-Free Three-Dimensional Cultivation of Pholiota microspora (Nameko Mushroom)
Harvesting: When the mushrooms reach 70-80% maturity, that is, when the veil membrane of the cap has not yet stretched, they can be harvested. When harvesting, hold the substrate surface with one hand and gently twist off the mushroom cluster with the other, so as to avoid pulling up large chunks of substrate. After each flush is harvested, tidy the substrate surface and withhold water for 5-7 days before managing the next flush. Advantages of this cultivation model: it saves the wooden poles needed to build racks. No need to thread curtains or build racks, saving resources and reducing labor intensity; high-altitude work is changed to low-altitude work, making it easier to operate. Moisture in the substrate is easy to maintain, and during fruiting
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Detailed Explanation of Key Technical Points for Pest and Disease Control in Large-Leaf Privet
Large-leaf privet (Ligustrum lucidum) has strong adaptability and is basically free of pests and diseases; only when its growth is too weak will scale insect damage occur. Control methods: 1. Use a grass bundle or brush to wipe and brush off the overwintering female insects on the trunk and branches and the male pupae inside the cocoons. 2. In May and June, spray for control with 50% malathion 600 times dilution, or 25% imidan 1000-1500 times dilution, or 40% dimethoate emulsifiable concentrate 1000 times dilution, or 10% fenbutatin oxide 400 times dilution.
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Detailed Explanation of the Characteristics and Cultivation Techniques of the Large-leaf Privet
Scientific name Ligustrun lucidum Ait., also known as wax tree, Oleaceae, Ligustrum genus. It is an evergreen large shrub or tree, with grayish-brown bark, smooth and not fissured. The leaves are 8-12 cm long, leathery and glossy, remaining green through winter, making it a rare evergreen broadleaf tree in temperate regions. The trunk is upright or two or three trunks emerge together, branches spread obliquely, forming a broad ovate, rounded crown. It can be planted as a street tree, tolerates pruning, and is commonly used as a hedge. The wood is fine and dense, used for joinery. The fruit contains starch and can be used for brewing wine, and is also used medicinally as a tonic.
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