Leaf Blight On Cabbage 31/07/2021

Ph.D Nguyen Minh Tuyen

Cabbage is one of the vegetables that are favored by the market and consumed all year round, in large quantities. Therefore, cabbage cultivation often gives high economic income. However, pests and diseases are one of the factors that increase costs and hinder production. One of the diseases that are difficult to control and cause significant damage to the production and quality of cabbage is leaf blight.

* Symptoms and effects:

On mature or rolled plants, the lesion causes dry burn from the leaf margin and is often V-shaped, with the pointed tip towards the main vein. Multiple lesions can appear together and grow larger gradually, causing the entire leaf to dry out and fall prematurely. The disease can spread to many other leaves, causing the cabbage to be exhausted, the cabbage to be small and light, or unable to roll.

After harvesting, during transportation or storage, the disease can continue to spread to other cabbages, reducing the commercial value.

 

* Pathogens and conditions of development:

Cabbage blight disease caused by Xanthomonas sp.

In conditions of high density planting, excess nitrogen fertilization, plants are too young, dense leaves, combined with gardens often watered in the style of rain spray, gardens with excess water, too low humidity,... the disease is often severe. The disease also often arises and thrives in rainy weather conditions - high winds, heat, humidity, and high pest density in the garden..

* Highly effective preventive measures:

The principle is to apply a combination of many measures.

- Clean the remnants on the garden before planting and use disease-free seedlings. Treat the soil or rotate it with crops other than cruciferous plants when the garden is seriously diseased.

- Plant vegetables with appropriate density to ensure ventilation, less rubbing together.

- Raise the bed high enough to help the garden open and dry after rain or watering.

- Limit watering in the form of rain spray with great pressure, so irrigation should be in the trench. Depending on the soil structure, there is a suitable irrigation regime to ensure enough moisture, not excess water.

- Pest control to limit causing mechanical wounds and invading diseases..

- Prune the old leaves to allow the root to be ventilated.

- When taking care, limit damage to vegetable plants.

- Use CALCIUM NITRATE to help increase disease resistance.

- Enhance decomposed manure, apply fertilizer in full balance, do not apply excess nitrogen, avoid young softening.

- Use fertilizer TANO-601 to provide necessary micronutrients to increase resistance.

- In the period of heavy rain and wind, it is necessary to check to detect diseases for timely prevention, or proactively spray to prevent diseases, which will help reduce damage and reduce prevention costs.

- When detecting early disease in the vegetable garden, immediately use one of the less toxic biological products such as SAIPAN 2SL, or ALPINE 80WG. Then spray should be repeated after 4-5 days.

 

Same item

To prevent, in addition to plowing and burying weed seeds, collecting weed stalks and stumps left after tilling the land to burn, not letting weeds produce seeds in production fields, etc., the use of chemical products is still a measure. optimal because of its ability to thoroughly kill weeds, reduce labor and take advantage of more time than manual weeding.To prepare for the coming Summer-Autumn rice crop, we would like to introduce to you a very new product of Saigon Plant Protection Joint Stock Company, which is Butoxim 5GR. This is a granular product used for spreading by Saigon Plant Protection Joint Stock Company in research, production and distribution.

 

 Miner has the scientific name Phyllocnistis citrella Staint., family Phyllocnistidae, order Lepidoptera. The  miner occurs in many countries in the tropics and subtropics. The main host of the miner is the citrus family - Rutaceae. In addition, the miner also attacks mangosteen and some other plants.

 

Adult is a small planthopper, with a body 2-3 mm long, the whole body is ash gray, slightly greenish, the wings are opaque with many small brown spots.Eggs are oval, 0.3 mm long, have a pointed end and are attached directly to the leaf surface, leaf axils.Larvae are very small, oval in shape, newly hatched are bright yellow. Age 2 and age 3 are in green. Age 4 and age 5 are golden brown and 2 small wing sprouts.

 

Green bugs specialize in the fruit of citrus groups (oranges, tangerines, lemons, grapefruits, kumquats...), some people call them orange bugs, or orange suckers. Their scientific name is Rhynchocoris poseidon or Rhynchocoris humeralis.

 In Vietnam, yellow leaf curl disease is very common on papaya trees, especially the disease is often severe in areas of high and continuous planting, areas with hot and arid climates. The disease has significantly reduced the yield and quality of papaya. Gardens that are infected early when the plants are young may not yield. However, up to now, many gardeners still do not know the cause and how to fix it.

 

 Spider mites are common pests on citrus trees, especially in hot and dry climates that are suitable for spiders to grow and cause severe damage.The group of harmful spiders is usually very small in size, unlike the natural enemy spiders.Spiders have a very short life cycle, high reproductive ability, create many generations in a year, so it is easy to break out into epidemics in a short time.

 

 This group includes species that are generally very small in size, causing damage by sucking plant sap (on leaves, fruits, branches, stems).

There are many species of mealybugs present on the group of Oranges,Tangerines,Grapefruits and Lemons (Citrus), which can be divided into 2 groups:

+ Group of sticky mealybugs with common varieties such as Lepidosaphes, Aonidiella, Coccus and Saissetia.

+ Group of flower mealybugs with common genera and species such as Pseudococcus, Planococcus and Icerya purchasi.

Dry branches and berries disease often appear to be common damage on coffee gardens during the rainy season. The disease causes death of branchs, dry fruit, severely affects the canopy structure and coffee yield if not paid attention to prevention.

  

 Pink disease commonly causes diseases on rubber plantations in the rainy season, especially on garden from 4-8 years old. This year, rubber has to go through a period of severe drought, weakening the tree, so now in tnshe rainy season it is easy to get infected. Therefore, it is necessary to pay attention to good management to avoid affecting the garden.

In recent years, the area of citrus has been expanded because it is a fruit tree with high economic efficiency. However, in order to sell at a high price, not only in quality but consumers also require the external beauty of the fruit, so pest management on citrus is a matter of great concern to farmers. The hot season is a favorable condition for thrips to develop and cause damage, affecting the commercial value of fruit.

  • Headquarters
  • SAIGON PLANT PROTECTION JOINT STOCK COMPANY
  • RQ 1, Nguyen Van Quy St., Tan Thuan Dong Ward, District 7, HCM City
  • Tax code: 0300632232
  • Tel: (028) 38 733 295 - 38 732 077
  • Fax: (028) 38 733 003 - 38 733 391
  • Website: www.spchcmc.vn - Email: info@spchcmc.vn
  • SAIGON PLANT PROTECTION COMPANY
  • SAIGON PLANT PROTECTION JOINT STOCK ENTERPRISE
  • Lot C1-C3 Hiep Phuoc Industrial Park, Hiep Phuoc Commune, Nha Be District, HCM City
  • Tel: (028) 3873 4089 - Fax: (028) 3873 4090
  • Affiliated Unit