MAX FACTS
growing tips, news and trivia
More Clues on Bee Die-offs
Honeybees have been dying off in huge numbers since 2006, and a new
study finds that a virus could be one cause. The tobacco ringspot virus has
mutated quickly and jumped from tobacco plants to soy plants to bees,
researchers say, and the annual increase in honeybee deaths between
autumn and winter correlates with an increasing number of infections. The
virus exists in pollen, and is likely spread as bees mix saliva, nectar and
pollen to feed their larvae. Mites might also be transmitting the virus when
they feed on bees. Some media outlets are calling the tobacco ringspot
virus a plant STD since it is spread as bees pollinate plants. This virus is
just the latest explanation offered for colony collapse disorder. While there
are a number of other factors to blame, such as pesticides, this is the first
known example of bees contracting a virus from pollen.
(Source: treehugger.com)
MAXFACTS
Growing tips, news and trivia
Catfish Growth
Putting the Heat in Hot Peppers
The genome of the hot pepper, the world’s most widely grown spice
crop, has been sequenced by a large international team of researchers, including scientists at the University of California, Davis. The new
reference genome sheds light on the biology of the pepper’s hallmark
pungency, or spiciness, as well as its fruit-ripening and disease-resistance mechanisms. It also reveals new information crucial for improving
the horticultural, nutritional and medicinal qualities of these peppers,
whose annual global production has grown more than 40-fold during the
past two decades and now exceeds $14.4 billion. The pepper genome
is one of the largest genomes assembled to date, say researchers, who
sequenced a hot pepper landrace, or domesticated variety, from the
Mexican state of Morelos. The variety, known as Criolo de Morelos 334,
has consistently exhibited high levels of disease resistance and is used
extensively in hot-pepper research and breeding.
(Source: news.ucdavis.edu)
22
Maximum Yield USA | March 2014
New USDA research has pinpointed the dissolved oxygen
concentrations needed to keep fish alive and growing.
Dissolved oxygen is the most critical water quality factor
in aquaculture. Traditionally, fish farmers relied on daily
observations to determine if catfish were getting
enough oxygen. If farmers saw fish sucking air at the
water surface, they turned on aeration equipment.
If oxygen gets too low, fish can die or become
partially asphyxiated. Lack of air causes fish to
lose their appetite. As a result, instead of
fish reaching market size in two years,
it may take four to five years. Using an
oxygen monitoring system to maintain
precise minimum dissolved oxygen
setpoints—3.0, 2.0 and 1.5 ppm—
researchers discovered the minimum
dissolved oxygen concentration for optimal
production is 2.5 to 3.0 ppm. At this level,
catfish growth significantly improved, fewer
fish died, feed conversion improved and
the production cycle was shorter.
(Source: ars.usda.gov)