Hi welcome to Taiga Bonzai, in this article we attempt to answer some of the questions that continue to perplex the most learned concerning the demise of flora. In many cases the answer is given in a reasonably short time frame, but there are instances where no definitive explanation can be agreed upon.

Introduction – with the planet constantly evolving evidence exists of events that have resulted, some have been of minor consequence whilst others have caused complete devastation for example.

In 1954, a swarm of locusts Schistocerca gregaria invaded Kenya covering an area of 200km². The estimated density was 50 million individuals per km², a total number of 10 billion locusts in that swarm. This caused a major catastrophe in the loss of crops resulting in a famine situation. Today not much has changed Africa still suffers from this onslaught.

Life expectancy – nothing on this planet lasts forever, all flora, fauna including humanoids have a life expectancy and nothing can change this phenomenon. Even planet Earth has a life expectancy, a subject for another time as the implications associated would make this article far too long. Nonetheless, for those of a inquisitive nature we point you to the NEW ATLAS and their scientific author Michael Irving, who wrote an article on this subject in March 01 2021. Link below.

https://newatlas.com/environment/earth-atmosphere-oxygen-life-expectancy/

Humanoids and fauna – it can be argued that a debate on these two species would make for interesting discussion and much has been written by notable academics. Including, Alfred Russel Wallace and Charles Robert Darwin, works include; The Descent of Man and Selection in Relation to Sex (1871), The Expression of the Emotions in Man and Animals (1872).

Flora – all humans especially government officials are responsible for the planet’s well being concerning plant life regardless of the scale. Pests and disease transmitted by our actions either knowingly or not have been in existence for thousands of years.

We have discussed this topic at length including the deadly disease Xylella fastidiosa, first discovered by plant pathologist Newton Pierce in 1892. A disease that is an aerobic, Gram-negative bacterium of the monotypic genus Xylella. This plant pathogen is transmitted exclusively by xylem fluid-feeding sap insects. 

There is no chemical control for X. fastidiosa as is the case for many pests and disease. Infected plants are destroyed to prevent the disease spreading further. Resulting in a loss of crop production costing vast sums of revenue to the tune of billions.

Although many countries are deeply concerned, they just cannot find common ground to find a solution to the problem. Yet they whine, moan and sabre rattle on unimportant trivial items, hence it is difficult to comprehend their logic and justification for such.

The enemy – most common plant pathogens are fungi, bacteria, mollicutes, parasitic higher plants, parasitic green algae, nematodes, protozoa, viruses, and viroids. Here is a brief description on these and their functionality should you encounter them.

Fungi – many people believe fungi are plants, this a misnomer they are neither plants nor animals, but organisms that form their own kingdom of life. The way they feed themselves is different from other organisms, they do not photosynthesize like plants nor do they ingest their food like animals.

Fungi can be deadly poisonous as in the ‘Death cap’ Amanita phalloides variety and is the world’s most toxic mushroom. It contains alpha-amanitin which is responsible for causing liver and kidney failure.

Bacteria – are both beneficial and pathogenic, beneficial bacteria are involved in such diverse processes as digestion in animals. Nitrogen fixation in the roots of certain legumes and the decomposition of animal and plant remains and sewage disposal systems.

Pathogenic bacteria called fastidious vascular bacteria grow in either the xylem or phloem tissues. They interfere with the transport of water and nutrients in the plant, vectored by sucking insects such as leafhoppers, planthoppers and psyllids.

Mollicutes – are parasites in the class of bacteria distinguished by the absence of a cell wall. The word ‘Mollicutes’ is derived from the Latin mollis and cutis. Individuals are very small, typically only 0.2–0.3 μm in size and have a very small genome size. The best-known genus in the Mollicutes is Mycoplasma colonies which show the typical ‘fried-egg’ appearance. (shown below)

Parasitic higher plants and Green algae – hemiparasites often referred to as water parasites, do injure their host plants, absorbing water and mineral nutrients from them. They possess chlorophyll and can manufacture their own carbohydrates by photosynthesis.

Green algae are a foliar disease most commonly seen in warmer climates or in greenhouses. The main organism is Cephaleuros virescens, a green parasitic alga whose usual hosts are plants with leathery leaves such as litchi, magnolias, hollies, rhododendrons and viburnums.

Nematodes – often called ’roundworms’ are the most numerous multicellular animals on earth. A handful of soil can contain thousands of the microscopic worms many of them parasites of insects, plants or animals. Free-living species are abundant, including nematodes that feed on bacteria fungi and other nematodes. There are nearly 20,000 described species classified in the phylum Nemata many of which are associated with disease.  
 

Protozoa – are a group of single-celled eukaryotes either free-living, or parasitic that feed on organic matter such as other microorganisms or organic tissues and debris. They come in many different shapes and sizes ranging from an Amoeba which can change its shape to Paramecium with its fixed shape and complex structure. Some are parasitic meaning they live in other plants and animals including humans where they cause disease. 

Viruses, and viroids – viruses are a submicroscopic infectious agent that replicates only inside the living cells of an organism. They infect all life forms from animals, plants and other microorganisms, including bacteria and archaea. Viroids are infectious pathogens, they are small single-stranded, circular RNAs. Unlike viruses, they have no protein coating, all known viroids are inhabitants of angiosperms (flowering plants) and most cause disease.

The hidden menace – is an undetected problem that remains hidden until it becomes visible, mainly caused by either insect damage, or that of fungi and canker. Signs are usually browning of the leaves or loss of leaf drop due to chlorosis and white fungus caused by Verticillium wilt sp., for which there is no effective treatment.

Verticillium wilt can lie dormant until the conditions are such that is activated, it can spread rapidly. There are various strains of this fungal disease including, (Verticillium albo-atrum, Verticillium dahliae), Fusariosis (Fusarium sp.) and decay caused by fungi from the genera Phytium, Alternaria and Botrytis. 

In the next post we continue this discussion as it is an important factor for the well being of plants. More information made public via written text can only be beneficial to those dealing with horticulture including bonsai. Until next time, BW, Nik.