Category Archives: agriculture

How to Strengthen the Immune System of Plants: biodiversity

n the past 150 years, the concentration of carbon dioxide in the atmosphere has risen from 280 parts per million (ppm) to 410 ppm. For farmers this is mixed news. Any change in familiar weather patterns caused by the atmospheric warming this rise is bringing is bound to be disruptive. But more carbon dioxide means more fuel for photosynthesis and therefore enhanced growth—sometimes by as much as 40%. And for those in temperate zones, rising temperatures may bring milder weather and a longer growing season. (In the tropics the effects are not so likely to be benign.) What is not clear, though, and not much investigated, is how rising CO2 levels will affect the relation between crops and the diseases that affect them…

Plant biology is altered substantially by a range of environmental factors. This makes it difficult to predict what effect a changing climate will have on particular bits of agriculture. Carbon dioxide is a case in point. It enhances growth of many plants but,  it also shifts the defences to favour some types of disease over others.

To make matters even more complicated, evidence is mounting that changes in temperature and water availability also shift plant immune responses. André Velásquez and Sheng Yang He, at Michigan State University, wrote an extensive review on the warfare between plants and diseases in Current Biology in 2018. They noted that though some valuable crops, such as potatoes and rice, experience less disease as moisture levels increase, this is not the case for most plants. High humidity, in general, favours the spread of botanical diseases. The same can be said for temperature—with some diseases, like papaya ringspot virus, thriving in rising temperatures while others, for example potato cyst, are weakened.

The problems are daunting, then, but there is a way to try to solve them… Genes which grant resistance to diseases that might become severe in the future need to be tracked down. Modern crops have been streamlined by artificial selection to be excellent at growing today. This means that they have the genes they need to flourish when faced with the challenges expected from current conditions, but nothing more. Such crops are thus vulnerable to changes in their environment.  One way to find genes that may alter this state of affairs is to look to crops’ wild relatives. Uncossetted by farmers, these plants must survive disease by themselves—and have been fitted out by evolution with genes to do so. Borrowing their dna makes sense. But that means collecting and cataloguing them. This is being done, but not fast enough. The International Centre for Tropical Agriculture, a charity which works in the area, reckons that about 30% of the wild relatives of modern crops are unrepresented in gene banks, and almost all of the rest are underrepresented….

[This is becuase] most countries are, rightly, protective of their genetic patrimony. If money is to be made by incorporating genes from their plants into crops, they want to have a share of it. It is therefore incumbent on rich countries to abide by rules that enable poor ones to participate in seed collecting without losing out financially. Poor, plant-rich countries are in any case those whose farmers are most likely to be hurt by global warming. It would be ironic if that were made worse because genes from those countries’ plants were unavailable to future-proof the world’s crops.

Excerpts from Blocking the Road to Rusty Death: Climate Change and Crop Disease, Economist,  Apr. 20, 2019

5,000 Eyes in the Sky: environmental monitoring

The most advanced satellite to ever launch from Africa will soon be patrolling South Africa’s coastal waters to crack down on oil spills and illegal dumping.  Data from another satellite, this one collecting images from the Texas portion of a sprawling oil and gas region known as the Permian Basin, recently delivered shocking news: Operators there are burning off nearly twice as much natural gas as they’ve been reporting to state officials.

With some 5,000 satellites now orbiting our planet on any given day…. They will help create a constantly innovating industry that will revolutionize environmental monitoring of our planet and hold polluters accountable…

A recent study by Environmental Defense Fund focused on natural gas flares from the wells in the Permian Basin, located in Western Texas and southeastern New Mexico. Our analysis proved that the region’s pollution problem was much larger than companies had revealed.  A second study about offshore gas flaring in the Gulf of Mexico, published by a group of scientists in the Geophysical Research Letters, showed that operators there burn off a whopping 40% of the natural gas they produce.

Soon a new satellite will be launching that is specifically designed not just to locate, but accurately measure methane emissions from human-made sources, starting with the global oil and gas industry.  MethaneSAT, a new EDF affiliate unveiled in 2018, will launch a future where sensors in space will find and measure pollution that today goes undetected. This compact orbital platform will map and quantify methane emissions from oil and gas operations almost anywhere on the planet at least weekly.

Excerpts from Mark Brownstein, These pollution-spotting satellites are just a taste of what’s to come, EDF, Apr. 4, 2019

Biodiversity and Respect for Human Rights

The instinctive response of many environmentalists  is to to fence off protected areas as rapidly and extensively as possible. That thought certainly dominates discussions of the Convention on Biological Diversity, the main relevant international treaty. An eight-year-old addendum to the pact calls for 17% of the world’s land surface and 10% of the ocean’s water column (that is, the water under 10% of the ocean’s surface) to be protected by 2020. Currently, those figures are 15% and 6%. Campaigners want the next set of targets, now under discussion, to aim for 30% by 2030—and even 50% by 2050. This last goal, biogeographers estimate, would preserve 85% of life’s richness in the long run.  As rallying cries go, “Nature needs half” has a ring to it, but not one that sounds so tuneful in the poor countries where much of the rhetorically required half will have to be found. Many people in such places already feel Cornered by Protected Areas.” (See also Biodiversity and Human Rights)

James Watson, chief scientist at the Wildlife Conservation Society (wcs), another American charity, has an additional worry about focusing on the fence-it-off approach. If you care about the presence of species rather than the absence of humans, he warns, “‘nature needs half’ could be a catastrophe—if you get the wrong half.” Many terrestrial protected areas are places that are mountainous or desert or both. Expanding them may not translate into saving more species. Moreover, in 2009 Lucas Joppa and Alexander Pfaff, both then at Duke University in North Carolina, showed that protected areas disproportionately occupy land that could well be fine even had it been left unprotected: agriculture-unfriendly slopes, areas remote from transport links or human settlements, and so on. Cordoning off more such places may have little practical effect.

Southern Appalachians, Virginia. image from wikipedia

 In the United States it is the underprotected southern Appalachians, in the south-east of the country, that harbour the main biodiversity hotspots. The largest patches of ring-fenced wilderness, however, sit in the spectacular but barren mountain ranges of the west and north-west. In Brazil, the world’s most speciose country, the principal hotspots are not, as might naively be assumed, in the vast expanse of the Amazon basin, but rather in the few remaining patches of Atlantic rainforest that hug the south-eastern coast.

Deforestation Atlantic Rainforest in Rio de Janeiro. Image from wikipedia

Nor is speciosity the only consideration. So is risk-spreading. A team from the University of Queensland, in Australia, led by Ove Hoegh-Guldberg, has used a piece of financial mathematics called modern portfolio theory to select 50 coral reefs around the world as suitable, collectively, for preservation. Just as asset managers pick uncorrelated stocks and bonds in order to spread risk, Dr Hoegh-Guldberg and his colleagues picked reefs that have different exposures to rising water temperatures, wave damage from cyclones and so on. The resulting portfolio includes reefs in northern Sumatra and the southern Red Sea that have not previously registered on conservationists’ radar screens…

Another common finding—counterintuitive to those who take the “fence-it-all-off” approach—is that a mixed economy of conservation and exploitation can work. For example, rates of deforestation in a partly protected region of Peru, the Alto Mayo, declined by 78% between 2011 and 2017, even as coffee production increased from 20 tonnes a year to 500 tonnes.

Environmental groups can also draw on a growing body of academic research into the effective stewardship of particular species. For too long, says William Sutherland, of Cambridge University, conservationists have relied on gut feelings. Fed up with his fellow practitioners’ confident but unsubstantiated claims about their methods, and inspired by the idea of “evidence-based medicine”, he launched, in 2004, an online repository of relevant peer-reviewed literature called Conservation Evidence.  Today this repository contains more than 5,400 summaries of documented interventions. These are rated for effectiveness, certainty and harms. Want to conserve bird life threatened by farming, for example? The repository lists 27 interventions, ranging from leaving a mixture of seed for wild birds to peck (highly beneficial, based on 41 studies of various species in different countries) to marking bird nests during harvest (likely to be harmful or ineffective, based on a single study of lapwing in the Netherlands). The book version of their compendium, “What Works in Conservation”, runs to 662 pages. It has been downloaded 35,000 times.

Excerpts from How to preserve nature on a tight budget, Economist, Feb. 9, 2919

Who is Afraid of Bats?

More than 50,000 of the fruit bats are thought to have been killed in Mauritius since 2015, in an attempt to protect fruit in orchards.  The bats – also known as flying foxes – are resorting to eating in orchards to survive because only 5 per cent of Mauritius’s native forests remain, animal experts warned.  Fruit bats are vital for biodiversity as they pollinate flowers and scatter seeds, enabling trees and plants to grow and spread, according to conservationists.  But populations of the flying foxes have fallen by more than 50 per cent in four years, said Vincent Florens, an ecologist at the University of Mauritius. Some believe fewer than 30,000 now remain.

The first cull, in 2015, killed 30,000, and in a second cull, the following year, 7,380 were targeted.  The latest cull involved 13,000.  Prof Florens said he believed the number killed is much higher than the 50,300 government figure.  “The culls took place late in the year, when many mothers were pregnant or had babies,” he told National Geographic. “You shoot one bat and basically kill two.” Others were likely to have been injured and died later, he said.

Scientists are supporting a lawsuit against the government on grounds of animal welfare violations to prevent any more culls…Mahen Seeruttun, Mauritius’s minister of agro-industry and food security, told FDI Spotlight: “We have a large population of bats who will eat fruit crops.

Excerpts from Endangered fruit bats ‘being driven to extinction’ in Mauritius after mass culls kill 50,000, Independent, Mar. 4, 2019

From Savior to Villain: Biofuel from Palm Oil

Globally, average palm oil yields have been more or less stagnant for the last 20  years, so the required increase in palm oil production to meet the  growing demand for biofuels  has come from deforestation and peat destruction in Indonesia.  Without fundamental changes in governance, we can expect at least a third of new palm oil  area to require peat drainage, and a half to result in deforestation.

Currently, biofuel policy results in 10.7  million tonnes of palm oil demand.  If the current biofuel policy continues we expect by 2030:
• 67 million tonnes palm oil demand due to biofuel policy.
• 4.5 million hectares deforestation.
• 2.9 million hectares peat loss.
• 7 billion tonnes of CO2 emissions over 20 years, more than total annual U.S. GHG emissions.
It must always be remembered that the primary purpose of biofuel policy in the EU and many  other countries is climate change mitigation. Fuel consumers in the European Union, Norway  and elsewhere cannot be asked to continue indefinitely to pay to support vegetable oil based
alternative fuels
that exacerbate rather than mitigate climate change.

The use of palm oil-based biofuel should be  reduced and ideally phased out entirely.  In Europe, the use of biodiesel other than that produced from approved waste or  by-product feedstocks should be reduced or eliminated.
In the United States, palm oil biodiesel should continue to be restricted from generating  advanced RINs under the Renewable Fuel Standard. Indonesia should reassess the relationship between biofuel mandate, and its  international climate commitments, and refocus its biofuel programme on advanced biofuels from wastes and residues. The aviation industry should focus on the development of advanced aviation biofuels  from wastes and residues, rather than hydrotreated fats and oils.

Excerpts from Dr Chris Malins,  Driving deforestation: The impact of expanding palm oil demand through biofuel policy, January 2018

In Feb. 28, 2019, Norway’s $1 trillion sovereign wealth fund, the world’s largest, pulled out of more than 33 palm oil companies over deforestation risks.

How Nuclear Technology Creates New Plants

Joining the FAO/IAEA coordinated research projects in the area of mutation breeding has led to the development of several barley mutant lines with improved yield and quality under Kuwait’s environmental conditions.  As arable land is limited to small areas, 95% of the country’s food and animal fodder is imported. Barley is a preferred crop for cultivation, because it is relatively drought tolerant and therefore one of the most suitable crops for an arid country like Kuwait. Having high yielding home grown crops is among the key objectives of the country’s agricultural programme to enhance food security.

Drought, salinity and diseases have historically limited staple crop productivity in Kuwait.   Mutation induction by radiation rapidly increases the genetic diversity necessary to produce new and improved varieties and is thus advantageous over traditional breeding…The best adaptable varieties were identified, and the seeds were subjected to induced mutation using gamma rays.

New mutant lines have been generated and they are now examined for drought and salinity tolerance. The selected mutant lines will be advanced, which then can be multiplied for planting. …One of the major challenges was explaining to farmers the safety of the new mutated barley lines developed. “When they heard that ‘nuclear techniques’ were used to create improved barely seeds, they got scared….

Aabha Dixit , Nuclear Technology Helps Develop New Barley Variety in Kuwait, IAEA Press Release, Feb. 18, 2019

Radical New Potatoes

Potatoes are already a staple for 1.3 billion people… but unlike other major crops, however, the potato has not had a breeding breakthrough of the kind that helped dramatically boost yields during the Green Revolution of the 1950s and 1960s. The reason is that creating a new potato variety is slow and difficult, even by the patient standards of plant breeders…Readying a new potato variety for farm fields can take a decade or more.  Many countries continue to plant popular potato varieties that have remained essentially unchanged for decades. But new approaches, including genetic engineering, promise to add more options. Potato breeders are particularly excited about a radical new way of creating better varieties. This system, called hybrid diploid breeding, could cut the time required by more than half, make it easier to combine traits in one variety, and allow farmers to plant seeds instead of bulky chunks of tuber

Solynta Hybrid Potato Seeds

To breed a better potato, it helps to have plenty of genetic raw material on hand. But the world’s gene banks aren’t fully stocked with the richest source of valuable genes: the 107 potato species that grow in the wild. Habitat loss threatens many populations of those plants. In a bid to preserve that wild diversity before it vanishes, collectors have made their biggest push ever, part of a $50 million program coordinated by the Crop Trust, an intergovernmental organization based in Bonn, Germany.

The Crop Trust has provided grants and training to collectors around the world. The effort on wild potatoes, which wraps up this month, has yielded a collection representing 39 species from six nations: Peru, Brazil, Ecuador, Guatemala, Costa Rica, and Chile. Zorrilla’s team alone found 31 species in Peru, including one for which no seeds had ever been collected. They plan to continue to search for four other species still missing from gene banks. “We will not stop,” she says. The plants are being stored in each nation’s gene bank, CIP, and the Millennium Seed Bank at the Royal Botanic Gardens, Kew, in the United Kingdom. The stored seeds will be available to potato breeders worldwide.

THE HARDEST PART comes next: getting desirable genes from wild species into cultivated potatoes….Other researchers are skirting the limitations of traditional breeding by using genetic engineering. CIP’s Marc Ghislain and colleagues, for example, have directly added genes to already successful potato varieties without altering the plants in any other way—an approach not possible with traditional breeding. They took three genes for resistance to late blight from wild relatives and added them to varieties of potato popular in East Africa.

Potato Blight , a disease affecting potatoes

The engineered varieties have proved successful in 3 years of field tests in Uganda and are undergoing final studies for regulators. Transgenic potatoes that resist late blight have already been commercialized in the United States and Canada….

Pim Lindhout has been plotting a revolution that would do away with much of that tedium and complexity. As head of R&D for Solynta, a startup company founded in 2006, he and his colleagues have been developing a new way to breed potatoes….Breeders reduce the complexity either by using species with only two sets of chromosomes (known as diploids) or by manipulating domesticated potatoes to cut the number of chromosomes in half. With persistence, diploid potatoes can be inbred. In 2011, Lindhout published the first report of inbred diploid lines that are vigorous and productive. More recently, Jansky and colleagues also created inbred diploid lines.

Such diploid inbred plants are at the heart of Solynta’s strategy to revolutionize potato breeding. Other firms, including large seed companies, are also working to develop hybrid potatoes. HZPC in Joure, the Netherlands, has begun field trials in Tanzania and in several countries in Asia.

Excerpt from Erik Stokstad, The new potato, Science, Feb. 8, 2019