Aster yellows

Aster yellows

Aster yellows is a chronic, systemic plant disease caused by a bacterium-like organism called a phytoplasma.[1] The aster yellows phytoplasma (AYP) affects 300 species in 38 families of broad-leaf herbaceous plants, primarily in the aster family. Symptoms are variable and can include phyllody, virescence, chlorosis, stunting, and sterility of flowers. The aster leafhopper vector, Macrosteles quadrilineatus, moves the aster yellows phytoplasma from plant to plant.[2] Its economic burden is primarily felt in the carrot (Daucus carota ssp. sativus) crop industry as well as the nursery industry. There is no cure for plants infected with Aster yellows. Infected plants should be removed immediately to limit the continued spread of the phytoplasma to other susceptible plants. However, in agricultural settings such as carrot fields, some application of chemical insecticides has proven to minimize the rate of infection by killing the vector.

Treatment

There is no cure for plants infected with Aster yellows. Infected plants should be removed immediately to limit the continued spread.

Click here for the original Source

Prevent and Control Powdery Mildew

Powdery mildew is a fungal disease that is one of the more common plant diseases that many home vegetable gardeners will experience. Powdery mildew is in the order of Erysiphales which contains one family named Erysiphaceae of which many cause powdery mildew.

Powdery mildew begins on a host plant, in this case one of your vegetable plants, when the sexual ascospores, or the asexual conidia germinating on the surface of the plants leaf or stem, resulting in septate mycelium of uninucleate cells.

Powdery mildew is one of the easier plant diseases to spot. If your plants are affected, what you will see are white powdery spots on the leaves and stems. Powdery mildew is most prominent on the lower leaves although powdery mildew will appear on the upper leaves as it progresses. If left untreated, the spots will get larger and more dense as more spores form.

Do you live in an area or environment where you will experience high humidity and moderate temperatures? If so, then you are more likely to experience Powdery mildew.

So what will powdery mildew do to your plants if not addressed? Chances are it won’t kill your plants, but will contribute to the reduction of fruit and vegetable yields.

While many home vegetable gardeners are looking for a cure for powdery mildew, one simply does not exist. So what you need to do is take steps to preventing and controlling powdery mildew. Two good things to make sure your plants are receiving in helping with prevention is air circulation and direct sunlight. Both have shown to inhibit powdery mildew formation.

But, let's say that powdery mildew already exists on your plants. What you have to do now is move into "control" mode. According to Organic Gardening, "Research studies in 1999 and 2003 on infected zucchini and winter wheat (respectively) indicated that spraying cow's milk slowed the spread of the disease."

By mixing 1 part milk and 9 parts water (by volume), you will create a spray that can then be applied to your affected plants. Also you can try a mix of 1 teaspoon of baking soda with 1 quart of water as a spray. This helps raise the pH, which is not a suitable environment for powdery mildew.

At the end of the season, remove all plants that were affected with powdery mildew, bag them up and throw them away. While some sources say they are ok to add to your compost pile, I take a more cautious stand and do not do so.

A Few Tips to Avoid Root Rot

Here in New Jersey we are experiencing a boat load of rain. Last I heard on the news, for our area, we are over a few inches above last year’s total at this same time. Last year’s total rainfall at this time were normal measurements. As Luke Bryan sings, Rain is a Good Thing. However, too much rain, is not a good thing for your vegetable plants.

Good drainage in your vegetable garden beds can prevent the most obvious issue which is root rot. Root rot is a disease that can occur in vegetable plants both indoors and outdoors, which is the decaying of a vegetable plants’ roots. Root rot will occur when the roots of your vegetable plants get too wet, which creates a perfect environment for various fungi that carry out this process.

As stated earlier, making sure the area where your vegetable plants reside has adequate drainage is a major key in preventing root rot. There a few solutions you can implement to prevent excess water around your vegetable plants’ roots.

For vegetable plants that you are growing indoors, let’s start with the obvious. Make sure that whatever your vegetable plants are planted in have enough drainage holes. You may have purchased a pot (or pots) from a home or garden center and think that it may have enough holes, but that is not always the case. Do not be afraid to drill a few more in the bottom of the pot, no less than ¼” in diameter. To prevent soil erosion in your pots, line them with newspaper before you put your potting soil in. This will allow the excess water to drain out, while keeping the soil in.

For your outdoor vegetable garden there are a number of solutions you can go with. For starters, build your garden beds up using raised beds. As vegetable gardening author Chris McLaughlin writes in her book Vertical Vegetable Gardening: A Living Free Guide, raised beds give you better drainage especially in areas wher clay soil dominates.

Many people that have raised beds, build them in such a way as there is no need to actually go into the bed itself and that helps by not compacting the soil every time a step is taken near their vegetable plants.

Finally, whether you are using raised beds or not, mix up a soil solution that aides in wicking away excess water. There are three great products that you can add to your soil before you plant that will help with this. They are peat moss, coir and perlite.

The peat moss and coir are interchangeable. Although you can, you would not use them together as they serve the same purpose. They make your soil loose and friable. Peat moss is far less expensive than coir, and one distinct advantage coir has over peat to justify the price, is coir is more environmentally friendly as a renewable resource since it is derived from the fiber of the outer husks of coconuts.

Peat moss, also referred to as Sphagnum (peat moss’ genus name), grows in dense masses on boggy ground. Peat bogs are valuable to wildlife habitat that rely on them. I was unable to locate any study findings as to how quickly or slowly peat regenerates itself once it’s stripped.

You would mix either peat or coir with perlite though. Perlite is a form of obsidian (A hard, dark, glasslike volcanic rock formed by the rapid solidification of lava without crystallization) consisting of glassy globules, used in plant growth.

Perlite helps loosen heavy soils (high clay content), aerate soil, prevent soil compaction, and aid in preventing overwatering. When it comes to perlite, a little goes a long way. So you do not need to add a lot to your garden beds.

The combination of using raised beds along with items that aid in preventing over watering will help with reducing the potential of root rot on your vegetable plants.