This will squeeze a significant gain in yield for corn likely on therange of perhaps another twenty percent. Corn is been subjected tomany other beneficial improvements that secures it position as theleading field crop. In time we will have a rich nutrient enhancedproduct that is welcome everywhere.
The conversion to corn culture worldwide continues to be rewardingand well rewarded and is handily providing us much of our foodsecurity. It will clearly continue to expand its range.
It is all good news for the long term as agriculture prepares toshift into organic methods.
Plant scientists atCSHL demonstrate new means of boosting maize yields
by Staff Writers
Cold Spring HarborNY (SPX) Feb 12, 2013
http://www.seeddaily.com/reports/Plant_scientists_at_CSHL_demonstrate_new_means_of_boosting_maize_yields_999.html
A team of plantgeneticists at Cold Spring Harbor Laboratory (CSHL) has successfullydemonstrated what it describes as a "simple hypothesis" formaking significant increases in yields for the maize plant.
Called corn by mostpeople in North America, modern variants of the Zea mays plant areamong the indispensable food crops that feed billions of the planet'speople. As global population soars beyond 6 billion and heads for anestimated 8 to 9 billion by mid-century, efforts to boost yields ofessential food crops takes on ever greater potential significance.
The new findingsobtained by CSHL Professor David Jackson and colleagues, publishedonline in Nature Genetics, represent the culmination of over a decadeof research and creative thinking on how to perform geneticmanipulations in maize that will have the effect of increasing thenumber of its seeds - which most of us call kernels.
Plant growth anddevelopment depend on structures called meristems - reservoirs inplants that consist of the plant version of stem cells. When promptedby genetic signals, cells in the meristem develop into the plant'sorgans - leaves and flowers, for instance. Jackson's team has takenan interest in how quantitative variation in the pathways thatregulate plant stem cells contribute to a plant's growth and yield.
"Our simplehypothesis was that an increase in the size of the inflorescencemeristem - the stem-cell reservoir that gives rise to flowers andultimately, after pollination, seeds - will provide more physicalspace for the development of the structures that mature intokernels."
Dr. Peter Bommert, aformer postdoctoral fellow in the Jackson lab, performed ananalytical technique on several maize variants that revealed whatscientists call quantitative trait loci (QTLs): places along thechromosomes that "map" to specific complex traits such asyield. The analysis pointed to a gene that Jackson has beeninterested in since 2001, when he was first to clone it: a maize genecalled FASCIATED EAR2 (FEA2).
Not long after cloningthe gene, Jackson had a group of gifted Long Island high schoolstudents, part of a program called Partners for the Future, performan analysis of literally thousands of maize ears. Their task was tometiculously count the number of rows of kernels on each ear. It waspart of a research project that won the youths honors in the IntelScience competition. Jackson, meantime, gained important data thatnow has come to full fruition.
The lab's currentresearch has now shown that by producing a weaker-than-normal versionof the FEA2 gene - one whose protein is mutated but still partlyfunctional -- it is possible, as Jackson postulated, to increasemeristem size, and in so doing, get a maize plant to produce earswith more rows and more kernels.
How many more? In twodifferent crops of maize variants that the Jackson team grew in twolocations with weakened versions of FEA2, the average ear had 18 to20 rows and up to 289 kernels - as compared with wild-type versionsof the same varieties, with 14 to 16 rows and 256 kernels. Comparedwith the latter figure, the successful FEA2 mutants had a kernelyield increase of some 13%.
"We were excitedto note this increase was accomplished without reducing the length ofthe ears or causing fasciation - a deformation that tends to flattenthe ears," Jackson says. Both of those characteristics, whichcan sharply lower yield, are prominent when FEA2 is completelymissing, as the team's experiments also demonstrated.
Teosinte, the humblewild weed that Mesoamericans began to modify about 7000 years ago,beginning a process that resulted in the domestication of maize,makes only 2 rows of kernels; elite modern varieties of the plant canproduce as many as 20.
A next step in theresearch is to cross-breed the "weak" FEA2 gene variant, orallele, associated with higher kernel yield with the best maize linesused in today's food crops to ask if it will produce a higher-yieldplant.
"Quantitativevariation in maize kernel row number is controlled by the FASCIATEDEAR2 locus" appears online in Nature Genetics on February 3,2013. The authors are: Peter Bommert, Namiko Satoh Nagasawa and DavidJackson. The paper can be viewed here
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