For 600 million rural people across Africa, the food they grow is the food they eat. A new plant breeding academy in Kenya is using advanced genomic technologies to produce more robust and nutritious crops, writes Howard-Yana Shapiro.
Growing Bt crops reduces the use of insecticides applied to them, but these crops could affect soil microorganisms and their activities. We evaluated the effects of Bt (Cry1Ab) corn... and deltamethrin... insecticide application on soil microbial biomass C (MBC), β-glucosidase enzyme activity (final season only), bacterial functional diversity, and bacterial community-level physiological profiles (CLPPs) in corn monoculture in five seasons.We also determined if growing Bt corn in crop rotation would alter these effects.
Statistical analysis of pooled data across seasons did not show any effects of Bt technology, insecticide application or crop rotation on soil microbial biomass or diversity even though differences between seasons and between the rhizosphere and bulk soil were observed.
Annual analyses of results also showed that neither the Bt technology nor insecticide application affected soil MBC, enzyme activity, or functional diversity of bacteria in corn rhizosphere, but shifts in bacterial CLPPs due to Bt trait were observed in one year.
Crop rotation effects on soil microbial properties were not observed in most cases. Where effects were observed, Bt corn grown in rotation resulted in greater MBC, enzyme activity and functional diversity than Bt corn grown in monoculture or conventional corn grown in rotation, and these effects were observed only in bulk soil.
Therefore, the Bt technology is safe with respect to the non-target effects measured in this study. However, the effects of repeated use of Bt crops over many years on the soil environment should continue to be monitored.
Chen M et al, 2012 - Plant Breeding Volume 131, Issue 5, pages 584–590
"2-acetyl-1-pyrroline (2AP) is the principal compound responsible for grain fragrance in rice. In fragrant rice cultivars, BADH2 (betaine-aldehyde dehydrogenase 2) is inactivated. Here, we describe the effect of amiRNA (artificial microRNA) transgenesis targeted at BADH2......"
Using a gene for a domestication trait (determinate growth) to study the multiple domestications of common bean.
"Background and Aims The actual number of domestications of a crop is one of the key questions in domestication studies. Answers to this question have generally been based on relationships between wild progenitors and ..."
Compatible/incompatible interactions between the tomato wilt fungus Fusarium oxysporum f. sp. lycopersici (FOL) and tomato Solanum lycopersicum are controlled by three avirulence genes (AVR1–3) in FOL and the corresponding resistance genes (I–I3) in tomato.
The three known races (1, 2 and 3) of FOL carry AVR genes in different combinations. The current model to explain the proposed order of mutations in AVR genes is: i) FOL race 2 emerged from race 1 by losing the AVR1 and thus avoiding host resistance mediated by I (the resistance gene corresponding to AVR1), and ii) race 3 emerged when race 2 sustained a point mutation in AVR2, allowing it to evade I2-mediated resistance of the host.
Here, an alternative mechanism of mutation of AVR genes was determined by analyses of a race 3 isolate, KoChi-1, that we recovered from a Japanese tomato field in 2008. Although KoChi-1 is race 3, it has an AVR1 gene that is truncated by the transposon Hormin, which belongs to the hAT family.
This provides evidence that mobile genetic elements may be one of the driving forces underlying race evolution. KoChi-1 transformants carrying a wild type AVR1 gene from race 1 lost pathogenicity to cultivars carrying I, showing that the truncated KoChi-1 avr1 is not functional. These results imply that KoChi-1 is a new race 3 biotype and propose an additional path for emergence of FOL races: Race 2 emerged from race 1 by transposon-insertion into AVR1, not by deletion of the AVR1 locus; then a point mutation in race 2 AVR2 resulted in emergence of race 3.
What happened in 2003 was of course that the genetic code – that is the sequence of bases in DNA – was revealed for the entire human genome, but even more astonishing is what happened next. Even computing science can't match that ...
If you (or your children) turn up your nose at brown apple slices, would you prefer fresh-looking ones that have been genetically engineered? Neal Carter, president of Okanagan Specialty Fruits... certainly hopes so. His company has created the new, non-browning, "Arctic" apples, and he's hoping for big orders from despairing parents and food service companies alike.
Food service companies, he says, would no longer have to treat their sliced apples with antioxidant chemicals like calcium ascorbate to keep them looking fresh. The cost savings "can be huge," he says. "Right now, to make fresh-cut apple slices and put them in the bag, 35 or 40 percent of the cost is the antioxident treatment. So you could make a fresh-cut apple slice 30 percent cheaper." ...
The non-browning trait was created by inserting extra copies of genes that the apple already possessed. These genes normally create an enzyme called polyphenol oxidase, which is responsible for the chemical reaction that causes browning... The USDA has studied the apple and released a preliminary conclusion that Arctic apples are pretty much as harmless as conventional ones...
Okanagan Specialty Fruits does not plan to grow large quantities of apples itself. It will license its variety to commercial growers, charging them a one-time fee of $1,500 per acre of trees. Carter says this is comparable to the license fees that growers currently pay for the right to produce patented varieties such as Gala or Fuji.
Carter is convinced that most consumers will be curious to try the apple. The company conducted focus groups... and asked them, "Would you buy it?" "Typically, it's about 80-20," says Carter. "80 percent say, 'Fantastic, bring it on.' And 20 percent say, 'Hmm. I don't think I like genetic engineering.' But they all eat it. Even if they were a nay-sayer that was never going to eat any GM fruit, they will eat a slice...
China has sacked three officials for breaching Chinese laws and ethical regulations during a trial in which children were fed genetically modified rice. The trial’s legitimacy was questioned in August by the environmental group Greenpeace. A three-month investigation, led by the Chinese Center for Disease Control and Prevention (CDC), culminated in the decision on 6 December to sack two members of the CDC’s own staff — Yin Shi’an, the principal investigator of the Chinese arm of the project, in Beijing, and Hu Yuming at the CDC's regional office in Hunan province, where the study took place — as well as Wang Yin, head of science and technology at the Zhejiang Academy of Medical Sciences...
Forms of Hordeum vulgare ssp. vulgare (barley) that possess a naked caryopsis are an important human staple and are mainly found today in eastern Asia. However, naked barley has not always been an eastern crop: archaeobotanical data show that it was prevalent in Europe and the Near East during various periods in prehistory. In this review we have collated data on the incidence of hulled and naked barley at archaeological sites in Europe and the Near East from two sources: archaeobotanical literature reviews and an archaeobotanical database, both assembled by Helmut Kroll. We have also examined the incidence of hulled and naked barleys in extant germplasm collections. Our compilation of this archaeobotanical data has enabled us to elucidate long-term changes in the ratio of hulled to naked barley under cultivation in these regions; specifically, these records show that naked barley begins to disappear from the archaeobotanical record from the Chalcolithic/Bronze Age onwards in the Near East, and from the Iron Age/Roman periods onwards in Europe. We discuss the possible causes of this decline in naked barley cultivation in these regions, along with the present-day prevalence of naked barley landraces in eastern Asia, particularly in relation to genetic evidence, which shows that naked barley has a single origin.
Dienekes' Blog posts on two papers that build on the controversies about barley and rice domestication:
(1) Tibet is one of the centers of domestication of cultivated barley by Fei Dai, & al. in PNAS, and (2) A map of rice genome variation reveals the origin of cultivated rice, by Xuehui Huang et al.in Nature.
"Sub-Saharan Africa's population is expected to reach 1.5–2 billion by 2050. Already the population is ballooning; in many areas, the risk of drought and flood is increasing; most soils are poor; and richer nations are buying up Africa's arable land for their own food or fuel security. African farmers have demonstrated the promise of perenniation. It is time to scale up its use and put it firmly on the research-and-development map."
A gene from wild Indian rice plants can significantly raise the yield of common varieties in nutrient-poor soils. Scientists from the International Rice Research Institute (IRRI) identified a gene that helps uptake of phosphorus, nitrogen and potassium, and transferred it into commercial strains. Their yield was about 60% above normal in phosphorus-poor soils, the team reports in the journal Nature. Large swathes of Asia have soil that is phosporus-deficient.