にんじんの種はとても小さいです、 したがって、細かいストレーナーを使用するか、シードを細かいメッシュのチーズクロスに入れてこの熱処理を行うと役立ちます。 You need the hot water to reach all of the seeds to sterilize any bacteria or fungi on their surface, so it is easiest to do this in small batches.
Bacterial or Microbial Diseases
Bacterial diseases often develop if the weather is warm and there’s a lot of humidity around your plants. These conditions make it more likely that bacteria in your soil will make it into your produce. It can also continue to thrive in plant debris, so maintain a clean garden.
A number of bacterial soft rots (Erwinia carotovora, Erwinia chrysanthemi, and Pseudomonas marginalis in particular) can strike carrots. These turn the carrot root to mush, softening it so the bacteria can feed and leaving the outer skin of the carrot intact.
There are no treatments for bacterial soft rot once it occurs, so you’ll need to dispose of all affected plants. The bacteria may remain in the soil for a while afterward and prevent you from further planting, but solar sterilization by super-heating the soil can kill it off if done properly.
Bacterial leaf blight (Xanthomonas campestris) is also a risk. This causes brown spotting on the carrot leaves, often surrounded by a yellowish halo. A sticky, amber-hued goo may also be visible oozing down from the leaves and is exuded by the bacteria.
This particular blight is usually seed-borne, and so your best bet to avoid it is to purchase seeds from reliable sources that are bacteria-free. You can also be able to do a hot water seed treatment to kill off Xanthomonas bacteria on home-grown seeds.
べと病 (Peronospora umbellifarum) is a disease caused by oomycetes, a form of microbe. While it colonizes similarly to the fungal powdery mildew, it produces a darker spore and can rapidly spread through your carrot greens, causing damage to the foliage.
I prefer to use a copper-based fungicide such as Monterey Liqui-Cop to treat downy mildew when it surfaces, しかし neem oil is a good preventative.
Fungal Diseases
A number of fungi also wreak havoc in your carrot beds. Let’s go over some of these.
Two different alternaria fungi cause two different forms of damage. Alternaria dauci causes carrot leaf spot 、 and alternaria radicina can cause black rot on the roots before and after harvest. Treatment with a liquid copper fungicide such as Monterey Liqui-Cop is advised.
Another leaf blight is caused by cercospora fungi. NS cercospora leaf blight looks very similar to the alternaria leaf blight, and treatment with Monterey Liqui-Cop is also recommended for this particular blight issue.
Sclerotinia sclerotiorum causes what’s called cottony soft rot 。 Also called white mold, this disease creates white, cottony masses at the top of the root, and can cause a distinctive soft, liquidy rot in the root mass. This is a complicated one to combat as few organic measures treat it.
One thing which is becoming more common in the fight against cottony soft rot is a beneficial fungus, Coniothyrium minitans 。 This fungus can prevent development of the cottony soft rot and protect your carrots when combined with good crop rotation techniques.
Rhizoctonia fungi can cause two different symptoms. In newly-sprouted plants, it can cause ダンピングオフ 。 In older plants, it causes the plant to develop crown rot 。 Both are typically caused by リゾクトニアソラニ 、 a common culprit in the home garden.
The usual culprit for Rhizoctonia development is warm, overly-wet soil or foliage. If your soil is holding too much water, this may become a recurring problem. Provide good airflow around your plants and ensure your soil is well-draining.
Pythium fungi 原因 減衰オフ in new carrot seedlings and fungal cavity spot in older ones. It often occurs in conjunction with Rhizoctonia fungal growth.不幸にも、 it’s also quite destructive when it occurs, and crop rotation doesn’t help.
This fungi is spread through flowing water, and so it’s important to provide well-draining soil and to avoid splashing of soil particulates onto the carrot tops. Using a soaker hose to water with is generally a safe choice. There is no treatment other than destroying infected plants.
One other form of 減衰オフ is spread by Fusarium fungi 。 Also known as fusarium wilt 、 it has very few treatment solutions and can dwell in your soil for years.ありがたいことに、 damping off is the only common effect that fusarium can have on your carrot crops.
いくつか mycorrhizal treatments have shown promising signs in reducing fusarium in the soil. Products like MycoStop may be an option for preventing fusarium development, and they can help with other fungi as well.
灰色かび病 is often referred to as grey mold 、 and it is relatively easy to treat as long as you catch it early in its development. Use a liquid copper fungicide such as Monterey Liqui-Cop to treat this condition.
Last on the fungal list is うどんこ病 。 While nowhere near as destructive to carrots as some of these other fungal diseases are, it can slow the plant’s ability to create chlorophyll, which can result in plant stunting. Regular spraying of neem oil will wipe this problem out.
Viral Diseases
When viral diseases strike, usually nothing can stop them. Infected plants will have to be destroyed. Often spread by aphids or leafhoppers, these can become extremely destructive, and eliminating the pests is your best means of protection.
The two most common viral diseases when growing carrots are aster yellows と mosaic viruses 。
Aster yellows is caused by a phytoplasma, a form of bacteria. It’s distributed by leafhoppers and causes chlorosis (yellowing) of the carrot leaves, as well as causing leaves to grow stunted or to easily break off at the slightest touch.
Mosaic viruses can also strike your plants. Most commonly, NS celery mosaic virus また きゅうりモザイクウイルス are the most common in carrot crops, が alfalfa mosaic virus is starting to impact carrots as well.
The majority of mosaic virii are transmitted by aphids. Like aster yellows, carrots infected by mosaic viruses should usually be destroyed.しかし、 if the infection happens right before harvest, you may be able to harvest early and still consume the carrot root.
Carrots do have a lot of random problems, but once you’ve grown them once, you’ll never want to buy carrots at the supermarket again. What’s your favorite carrot variety? Do you prefer the exotic or the tried-and-true? Tell me about your carrot patch in the comment section!
