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Once a majestic black diamond, now a glistening, oily turquoise. Its leaves widen at the tip and then abruptly narrow, a unique form displaying its proud and imposing stature. Learn a little each day, improve a little each day!

I. Broad Mite 1. Occurrence and Damage: Broad mites are very small, invisible to the naked eye, but reproduce rapidly. At 28-32℃, they reproduce one generation every 4-5 days; at 18-20℃, one generation every 7-10 days, with approximately 25 generations per year. They mainly reproduce and cause damage in greenhouses, primarily affecting the tender leaves at the top of the plant. As the tender leaves age, the damage shifts to the new tender leaves, hence the name "tender leaf mite." Infested leaves turn brown and shiny on the underside, become twisted and deformed, and in severe cases, the top dries out. Infested flowers and fruits prevent flowering and fruit setting; the fruit peel becomes yellowish-brown, corky, and cracked. 2. Control methods: Use 73% chlorpyrifos at a dilution of 1000 times, or 5% carbaryl EC at a dilution of 1000-2000 times, or 15% fenvalerate EC at a dilution of 1500 times, or 5% nissorun EC at a dilution of 2000 times. Spray once every 5-7 days, for 2-3 consecutive applications. In addition, after harvesting the previous crop, promptly remove and burn all remaining branches and leaves, and spray the entire greenhouse with pesticide to kill any remaining insects.

II. Spider Mites 1. Occurrence and Damage: The main spider mites affecting greenhouse vegetables in winter and spring are the carmine spider mite and the two-spotted spider mite. They have approximately 20 generations per year. Severe infestations occur under high temperature and dry conditions (optimal development temperature is 21-30℃), while temperatures exceeding 30℃ and humidity greater than 70% are unfavorable. They damage leaves by sucking sap with their piercing-sucking mouthparts on the underside of leaves, forming a web. Affected leaves turn pale green, develop small white spots, and eventually wither. They generally damage the lower leaves first, then spread upwards. 2. Control Methods: Refer to the control guidelines for broad mites. III. Aphids 1. Occurrence and Damage: There are three main types of greenhouse aphids: melon aphids, bean aphids, and peach aphids. They have 20-30 generations per year and cause damage year-round. Aphids congregate on the undersides of leaves and tender stems, sucking plant sap with their piercing-sucking mouthparts, causing leaves to turn yellow, curl, and even die. In addition, aphids transmit viral diseases, causing significant damage. 2. Control methods: 10% aphid-killing wettable powder at 2500 times dilution, or 10% cypermethrin at 2000 times dilution, or 50% pirimicarb at 2000 times dilution can be used for control. Spray once every 3 to 5 days, for 2 to 3 consecutive sprays. Aphid-killing smoke agent can also be used for control, with 350 grams per acre each time.

IV. Thrips 1. Occurrence and Damage: Thrips mainly damage melons, eggplants, legumes, and other vegetables. Nymphs are yellow, while adults are brownish-yellow, hence the name "brown-yellow thrips." There are approximately 15 generations per year, with overlapping generations throughout the year. They primarily feed on the undersides of leaves or burrow into petals, sucking sap from tender leaves, shoots, flowers, and young melons. Affected shoots, flowers, and young melons turn dark brown, harden, and shrink, severely impacting growth. 2. Control Methods: Use 25% acetamiprid water-dispersible agent at an 8000-fold dilution, or 5% thiamethoxam suspension at a 2500-fold dilution. Spray every 3 to 5 days, for 2 to 3 consecutive applications. Alternatively, fumigate the protected area with smoke before evening, using 0.5 kg of 20% dichlorvos smoke agent per acre to kill adults.

V. Leafminer Fly 1. Occurrence and Damage: Leafminers mainly damage legumes, solanaceous vegetables, cruciferous vegetables, as well as scallions and leeks. Adults lay eggs inside the leaf mesophyll, and larvae bore into the leaf mesophyll, causing the leaves to lose their green color and turn white. 2. Control Methods: After harvesting vegetables, promptly remove and burn any remaining branches and leaves to reduce pest infestation. In addition, spray with 75% wettable powder of chlorpyrifos at a dilution of 5000 times, or 10% high-efficiency cypermethrin at a dilution of 2000 times, or 52.25% chlorpyrifos EC at a dilution of 1000 to 1500 times, or 80% dichlorvos EC at a dilution of 1000 times, once every 3 to 5 days, for 2 to 3 consecutive applications. During the peak adult emergence period, apply 2000 times dilution of carbaryl dispersible concentrate or 25000 to 30000 times dilution of 70% imidacloprid dispersible granules, for 2 to 3 consecutive applications.