Selection of Broccoli Varieties for Summer Planting, Seedling Raising, Transplanting, and Pest and Disease Control Techniques

Broccoli, also known as green cauliflower, Italian cauliflower, Italian kale, tree cauliflower, green cauliflower, stem cauliflower, and broccoli. It is easy to cultivate, has a long supply period, and has great development prospects.So which varieties can be chosen for summer broccoli planting? How to raise seedlings and transplant? What are the pest and disease control techniques?

I. Variety Selection

For summer sowing, choose Xinxiu, Yousheng, and Japanese Lvxue, which are rain-tolerant, have slightly thicker flower buds, and are disease-resistant.

II. Seedling Raising

Since broccoli is a high-grade export vegetable with expensive seeds, the soil must be finely prepared to improve sowing quality and reduce production costs. For seedling bed raising, choose vegetable land with fertile, loose soil, good ventilation, light penetration, and convenient drainage and irrigation. Apply sufficient base fertilizer, mix with carbendazim to disinfect the soil, and make a seedling bed 1-1.2 m wide with high furrows. Irrigate with sufficient bottom water, then sow. Sow about 25-30 g per 6-7 sq m of seedling bed, which can provide seedlings for 1 mu of field. After sowing, spread a layer of screened culture soil made of half manure and half soil, just enough to cover the seeds. During the seedling bed period, use mancozeb or metalaxyl spray to control cabbage black leg disease. Transplant when there are 5-6 leaves.

III. Field Soil Preparation and Transplanting

Choose a field with loose, fertile soil, good drainage, and no clubroot disease. Before plowing, apply 2000-3000 kg of organic fertilizer per mu, 30 kg/mu of phosphorus, potassium, and compound fertilizer, and 0.5 kg of borax. For acidic soil with a pH below 5.5, apply 50-100 kg of quicklime per mu before making the beds to neutralize soil acidity, and make beds 1.5-2 m wide including the ditch.

Use high-bed cultivation. When transplanting, the plant spacing and row spacing should be about 40×40 cm.

IV. Field Management

From transplanting to survival, pay attention to watering to help the seedlings recover. After survival, appropriately reduce the frequency of watering to promote root growth. During the vigorous vegetative growth period and the curd formation period, increase the amount and frequency of irrigation to prevent drought. During the rainy season, pay attention to drainage to prevent waterlogging.

Broccoli has a high fertilizer requirement, so topdressing should be applied in a timely manner, following the principle of “promote early, control midway, and push late.” After transplanting and survival, apply 10 kg of urea, 20 kg of calcium superphosphate, and 10 kg of potassium fertilizer per mu dissolved in water. In the early bud emergence stage of the curd, foliar spray boron fertilizer and molybdenum fertilizer at a concentration of about 0.2%. When the curd grows to 4-5 cm in size, apply 15 kg of urea, 20 kg of calcium superphosphate, and 10 kg of potassium fertilizer per mu dissolved in water, and water after fertilizing. Every 10 days, spray once with 0.5% urea, 0.2% potassium dihydrogen phosphate, and 0.2% borax water to facilitate the rapid growth of the main curd and the development of side-shoot buds.

V. Pest and Disease Control

(I) Diseases

1. Downy mildew: spray with 69% dimethomorph · mancozeb wettable powder at 500 times dilution, or 80% mancozeb (Dithane) wettable powder at 600 times dilution, or 72% cymoxanil · mancozeb (Curzate) at 600 times dilution, or 25% metalaxyl wettable powder at 800 times dilution, or 75% chlorothalonil wettable powder at 700 times dilution, alternating the chemicals.

2. Black spot disease: spray with 10% difenoconazole (Score) water-dispersible granules at 1000-1500 times dilution, or 50% iprodione (Rovral) wettable powder at 1000 times dilution.

3. Black rot: spray with 70% fenaminosulf wettable powder at 1000 times dilution, or 72% agricultural streptomycin sulfate soluble powder at 4000 times dilution, or 90% streptomycin? soil (Xinzhimeisu) soluble powder at 4000 times dilution, or 77% copper calcium sulfate (Duoning) wettable powder at 600 times dilution for control.

(II) Insect Pests

1. Aphids: spray with 50% pirimicarb wettable powder at 2000 times dilution, or 10% imidacloprid wettable powder at 4000 times dilution, or 2.5% deltamethrin at 3000 times dilution for control.

2. Diamondback moth: use physical insect-killing lamps to trap and kill adults. Promote the use of biological pesticides to reduce resistance and achieve long-lasting control. Choose 1.8% abamectin emulsifiable concentrate at 4000 times dilution, or 10% chlorfenapyr (Chujin) suspension concentrate at 1200-1500 times dilution, or 2.5% spinosad (spinosyn) suspension concentrate at 1000-1500 times dilution, or 3% acetamiprid emulsifiable concentrate at 1000-1500 times dilution for spray control.

3. Cabbage caterpillar: refer to diamondback moth for chemical control.

4. Leafminer: remove vegetable residues damaged by leafminers; use fly-killing paper and yellow sticky boards to trap and kill adults; begin spraying as soon as egg-laying marks and feeding holes are seen. Select the right pesticide and alternate their use. The following chemicals can be chosen for control: (1) 48% chlorpyrifos emulsifiable concentrate 50 mL added to 20-50 kg of water for uniform spraying; (2) 5% abamectin emulsifiable concentrate at 3000 times dilution sprayed at the early stage of pest occurrence; (3) 75% cyromazine (Qianke) wettable powder at 5000-7000 times dilution for spraying; (4) 5% flufenoxuron (Cascade) floating oil at 2000 times dilution for spraying.