Friday, October 21, 2016

Gene Editing - Developing A Hornless Cow

Gene editing potentially offers a fast track to some significant breakthroughs in genetics.

A recent case is relevant with hornless cows developed through some simple gene editing.

The story goes like this.........

Dairy cows, which come from the Holstein breed, naturally grow horns. On farms, the horns are often physically removed because they can pose a threat to other cows, a well as to farm workers handling the cattle. 
typical Friesian heifer - note horns

But a group of researchers from the University of California, Davis has developed a method to remove the horns through gene-editing. 

The team inserted a gene from the naturally hornless Angus breed to create hornless Holsteins [ often called Friesian cows in Australia]. 

Have the researchers developed a new type of cow, or are they just speeding up the breeding process? 

Animal geneticist Alison Van Eenennaam, who led the research, and Jennifer Kuzma from the Genetic Engineering and Society Center talk about the future of biotechnology in agriculture, what defines a “genetically modified organism,” and how these technologies might be regulated.

Many regulatory authorities do not categorise gene editing as GM technology, as it is dealing with genes within the same species most commonly.

Whatever........it certainly offers a neat way to develop hornless cattle in breeds where horns are more common, as it is well known that horned cattle are prone to more damage and certainly have a reputation with causing injury to stock handlers, and themselves.

Friday, October 07, 2016

Zoysia matrella - Manilla Grass - History in North Australia



The first known widespread use of Zoysia matrella in northern Australia seems to be in Darwin at the Roman Catholic Cathedral in about 1963.  The church still has extensive areas of Z.matrella around the buildings with the Smith St frontage in very good condition, and at the adjacent residential buildings, although some areas are somewhat degraded from poor maintenance, low nutrition and ingress of weeds. The weedy grass Chrysopogon acidulatus has been a significant invader in some areas, as have a few other taller perennial grasses.

It seems that the material was sourced from the Philippines by a CSIRO rice agronomist/ breeder [ECB “Butch” Langfield] who spent considerable time at IRRI at Los Banos in the early 1960s as part of rice variety assessment, but along the way became intrigued by the turf common at IRRI as well as in parts of Manilla where it was used as turf.  The exact source is unknown.

However, it did come to Darwin through quarantine and was provided to the Bishop of Darwin during the building of the Cathedral in 1962-63, where it was planted.  The house site occupied by Butch Langfield at Humpty Doo CSIRO village also had a full Zoysia matrella turf area on the large house block by 1967.

The author developed an early interest in Z. matrella turf after seeing these areas and then found Z. matrella was present over a small area at the first house owned in Darwin [1968] and subsequently developed to plant the entire allotment.  The origin of the small patch is not definitively known but had been planted by the original house occupant, presumably from the Catholic Cathedral – it seemed to be the only place where it was grown.  Material was provided to others between 1968 – 1975 to start zoysia lawns, and by 1976 also used to plant another entire suburban allotment where a new house was built after Cyclone Tracy [and zoysia is still present as the turf on the lot].  

As far as is known, no commercial sod producer of zoysia was active in Darwin or anywhere else in the NT or Australia prior to this time, so use and movement was based around a few local enthusiasts who saw Z. matrella as a superior turf to the local strain of a very itchy Paspalum notatum also non commercially distributed as required between households.

An upsurge of interest in turf and garden activity occurred following Cyclone Tracy, and planting material was readily supplied to neighbours and colleagues.  The same materials were also supplied to the Department of Primary Industry at Berrimah Farm for turfing a large area around a new building there at around this time [1975 – 78], and propagation and herbicide evaluation trials carried out.   

Availability and use of slow release fertiliser from the late 1990s has also been an important cultural improvement for this relatively slower growing turf species, allowing steady but low levels of particularly nitrogen and potassium with reduced “surge” growth. 

Reduced problems with lawn grubs has also been noted with Z. matrella in the NT in comparison to most other local turf species with both leaf silica levels and use of slow release nitrogen possible beneficial factors.  It is also non-itchy to bare skin eg if laying or sitting on the turf.

Movement of the Z. matrella material seemed to transfer into the commercial arena in the late 1970s and the 1980s, capitalising on the early local success with Z. matrella with interest from a number of local nurseries who began using it for domestic landscaping projects and selling the product to householders, albeit in a modest way as plugs, not as full sod rolls.

The local type around Darwin which superficially appears morphologically close to Emerald, is now quite widespread, but several turf sod growers now also commercially supply other named lines including X japonica types mostly since the mid-1990s to meet local demand.

It is commonly known locally just as zoysia, not the more widespread common name Manilla grass.
Zoysia matrella lawns Legislative Assembly Darwin overlooking the harbour

The local zoysia was the turf of choice for the immediate areas around the new Legislative Assembly Building when constructed from 1990 [completed 1994] and the iconic site for this zoysia type is now on the Speakers Green outside the Great Hall of the Legislative Assembly overlooking Darwin Harbour.