Seed is one of Nature’s tiny miracles upon which the human race relies for its food and pleasure.
Each grain contains the genetic information for growth, development, flowering and fruiting for the preponderant plant life living on this planet. And when provided with adequate oxygen, moisture, warmth, light, physical support and nutrients germination will result in a new generation of a species. These vary from tiny short-lived alpines to the monumental redwood trees growing for centuries on the Pacific west coast of America.
Humankind has tamed and selected a few plant species for food and decorative purposes.
Seed head of beetroot, the seeds are in clusters.
Seed of these, especially food plants, is an internationally traded commodity. Strict criteria governed by legal treaties apply for the quality and health of agricultural and many horticultural seeds. This ensures that resultant crops are true to type and capable of producing high grade products as claimed by the companies who sell the seed.
Companies involved in the seed industry place considerable emphasis on ensuring that their products are capable of growing into profitable crops for farmers and growers. Parental seed crops are grown in isolation from farm crops thereby avoiding the potential for genetic cross-contamination. With some very high value seed the parent plants may be grown under protection and pollinated by hand.
Samples of seed are tested under laboratory conditions by qualified seed analysts. Quality tests identify levels of physical contamination, damage which may have resulted in harvesting and cleaning the seed and the proportion of capable of satisfactory germination. There may also be molecular tests which can identify trueness to type. Identifying the healthiness of seed is especially important. The seed coat can carry fungal and bacterial spores which could result in diseased crops. Similarly, some pathogens, including viruses, may be carried internally within seed.
Septoria apicola – seed borne pathogen causing late blight of celery
Pests, especially insects, find seed attractive food sources and may be carried with it. Careful analytical testing will identify the presence of these problems in batches of seed.
The capabilities of seed for producing vigorous plants is particularly important with very high value vegetable and salad crops. Vigour testing is a refined analytical process which tracks the uniformity and speed of germination supplemented with chemical tests determining the robustness of plant cells. Producers rely on the quality, uniformity and maturity rates of crops such as lettuce, green broccoli or cauliflower so they meet the strict delivery schedules set by supermarkets. Financial penalties are imposed for failures in the supply chain.
Biology’s seemingly inert tiny seed grains are essential ingredients of humankind’s existence!
This is only the latest in a litany of exotics to ravage American forests. Sixty-two high-impact insect species and a dozen pathogens have arrived since the 1600′s. Only two were detected before 1860.
The emerald ash borer. Image; Wikimedia Commons
Increased global trade and travel, along with climate change and warmer winters, are all fueling the problem. And the devastation has pushed scientists and foresters to look towards biotechnology for a remedy.
‘Almost every day there appears to be a new forest pest and some of these are quite devastating,’ says tree geneticist Jeanne Romero-Severson at the University of Notre Dame, Indiana, US.
‘Biotech approaches such as transgenic technology and CRISPR gene editing could be valuable tools in saving specific species.’
These biotech solutions look sexier to funders, and policymakers, and that is where the resources go. But in many ways, it is a dead end if you don’t have a foundational breeding programme to feed into,’ warns DiFazio, a plant geneticist at West Virginia University, US.
A technology like CRISPR for gene editing is fast and powerful, but mostly it is used in lab organisms where much is known about their genetics. Without deep knowledge of a tree’s genome, CRISPR will be far less useful.
CRISPR is a gene editing tool that first came to prominence in the 1990′s and is considered one of the most disruptive technologies in modern medicine.
Powell, a plant scientist at the State University of New York (SUNY), US acknowledges that ‘the biggest thing is to the get the public onboard; a lot of people are afraid of genetic engineering.
Surveys suggest that knowledge about genetic engineering technology, as well as about threats to forest health, is fairly low amongst the general public. Given these deficits, ‘public opinion might be vulnerable to changes,’ notes Delborne.
Scientists from the Department of Energy’s Lawrence Berkeley National Laboratory, California, US, have designed a method in which semiconducting materials have been turned into quantum machines.
This work could revolutionise the field, and lead to new efficient electronic systems and exciting physics.
Quantum machines are generally made from two-dimensional (2D) materials – often graphene. These materials are one atom thick and can be stacked. When the materials form a repeating pattern, this can generate unique properties.
Studies with graphene have resulted in large advancements in the field of 2D materials. A new study has found a way to use two semiconducting materials – tungsten disulphide and tungsten diselenide – to develop a material with highly interacting electrons.
The researchers determined that the ‘twist angle’ – the angle between the two layers – provides the key to turning a 2D system into a quantum material.
Dr Gary Harris talks about radio technology to quantum materials. Source: TEDx Talks
‘This is an amazing discovery because we didn’t think of these semiconducting materials as strongly interacting,’ said Feng Wang, Professor of Physics at UC Berkeley. ‘Now this work has brought these seemingly ordinary semiconductors into the quantum materials space.’
2D materials have a thickness of just one molecule, which makes them especially promising for use in quantum computing, as electrons are restricted by movement across two dimensions, as the wavelength of the electron is longer than the thickness of the material.
The most well known of these new materials is graphene – a single layer or carbon – which since its Nobel prize-winning synthesis in 2004 has been posited as a game-changer in applications ranging from tissue engineering and water filtration to energy generation and organic electronics.
Now, an international team at DTU led by Assistant Professor Kasper Steen Pedersen has synthesised a novel nanomaterial with electrical and magnetic properties that the researchers claim make it suitable for future quantum computers and other applications in electronics.
Since graphene’s discovery, hundreds of new 2D materials have been synthesised, but the new material, published in Nature Chemistry, is based on a different concept. While the other 2D material candidates are all inorganic, chromium-chloride-pyrazine (chemical formula CrCl2(pyrazine)2) is an organic-inorganic hybrid material.