WHAT TO DO WHEN SPRING


ONIONS TURN YELLOW?



Spring onions are an important ingredient in Chinese cuisine and can be grown all year round in Taiwan. However, starting from May, the rainy season arrives, and the weather is getting hot. Waterlogging and the control of pests and diseases become a challenging during this time. In recent years, in order to comply with the international trend of reducing pesticide risks and ensuring the safety of agricultural product, Integrated Pest Management (IPM) has been widely promoted. The fertilization management aspect of IPM helps plants maintain resistance and prevent or reduce the damages caused by waterlogging, drought, pests, and diseases resulting from climate change. It is better to prevent these risks than to remediate them after the damage occurs, making it an important component of agricultural and food safety.

 

 

The possible reasons cause spring onions turning yellow include

(1) poor drainage caused by heavy rainfall

(2) black/soft rot diseases

(3) Bulb mite

(4) root-knot nematodes

(5) nutrient deficiencies.

In addition to using plant protection materials, biological control, adding special elements through fertilization management to increase plant resistance and promote growth is also one of the methods. Especially in environments with poor drainage where the roots are unable to effectively absorb nutrients, supplementing nutrients through foliar application can be beneficial.

 

7 days after planting:

Root Forte 110 (Special for Rooting and Germination)

It contains Vitamin B complex, which is a natural stimulant that stimulates the roots, so that root hairs will continue to grow, and new leaves will continue to germinate.

- Nucleotides can enhance the root absorption capacity, activate the activity of ribulose diphosphate carboxylase to strengthen the ability of carbon dioxide fixation, and increase the chlorophyll content in leaves to promote photosynthesis.

- Glucose (a product of photosynthesis) can moderate a climate or environment with insufficient sunlight.

 

14 days after planting and use every 7 days:

Mix Go Growing 370 (Special for Growing, High in Nitrogen) and Ca Strong 801(Special for Summer and Water Retention)

- The combination of high nitrogen, phosphorus and potassium can make leaves grow fast.

- High calcium (Ca) and appropriate amount of silicon (Si) can enhance rapid expansion and thickening of stems and leaves, enhances the strength and stability of cell walls and tissues, and improves plant disease resistance and stress tolerance.

- Potassium (K) and lignin can promote rapid thickening of the stem epidermis and vascular bundles. Besides, lignin is a naturally occurring polymer in plants that helps against pests and pathogens.

It contains Betaine, which is a natural amphoteric surfactant that disrupts the permeability of pathogenic cell membranes, resulting in antibacterial effects.

Natural protection products can be use at all stage, performance in conventional farming (traditional farming) can use them during the safe harvest period.

Nafertino SP01(Plus) and Nafertino 01

Contain natural mineral and Silicon (Si), Nafertino SP01(Plus) has added chitosan, uses physical charges to adsorb pathogens, effectively reducing pathogen count and reducing the probability of disease occurrence.

Nafertino 03

Natural bitter tea extract, uses the tea saponin’s characteristics of non-ionic surfactants to block insect spiracle, increasing insect mortality and reducing feeding, making pests sluggish and inhibiting their reproduction.

 

 

Reference:

蔬菜類-生產管理手冊, 111.12版

https://www.agriharvest.tw/archives/95935

https://diag.tactri.gov.tw/Search/SiteSearch......

https://www.mdais.gov.tw/....../web_structure/6259/A01_1.pdf

https://money.udn.com/money/story/7307/6351669......