For a fortunate few, Harvest 2012 is drawing to a protracted and very difficult close, certainly this is a year that we aren't going to forget in a hurry!
It has been a revelation this year, a 'shake out' year as one of our breeders described it, as some serious issues that potentially threaten wheat breeding program's are starting to emerge with some very serious consequences for UK farming.
In the past some breeding program's have focused on genetic resistance to regular disease pressures, septoria tritici being the main one, with other traits being bolted on. Some other breeders have been focusing on all out yield, regardless of how genetically strong these varieties were, their consensus being that disease risk could be managed by chemistry tailored to curb disease outbreaks. Barn filling varieties with poor to average disease traits proliferated as farmers bought into the idea that chemistry could solve all disease problems. As with anything in nature, disease pressures and mutations give rise to new challenges. Single gene resistance to disease instead of dual, or multiple gene resistance is easier to breed into new varieties and allows quick turn around from lab to field. As a consequence we are now seeing multiple incidences of varieties succumbing to Yellow Rust and Brown Rust strains that are evolving, varieties that have only just been registered on the HGCA recommended lists, with the resultant increase in usage of full blown ag-chem programs to try and control these issues.
Throw into this mix one of the wettest growing seasons, especially from pre flowering all the way to harvest with low solar energy levels, high humidity and very damp soil conditions and you have a perfect storm scenario for a whole host of new diseases to make their presence felt too, especially Fusarium which has quite literally sucked all yield out of wheats this year, apart from those like Istabraq that has not suffered as much and is still producing a reasonable sample.
A common theme I am hearing on farm is a new level of questioning with regard to ag-chem inputs, how expensive this last season has been to get a crop that basically isn't near covering costs. It's is interesting to note how some of these chemistry suppliers have gone from small scale operations to giants in the industry in a very short period of time, considering how long the 'green revolution' in agriculture has been going on for. In a very short time span, farmers have seen their supply base of agricultural chemicals diminish considerably down to just a handful of players in the market, with the agronomy angle reduced even further and geared almost exclusively to structured spray programs. In a wet year like this last one, total reliance on sprays to control disease has been severely tested and the basic fundamentals of genetic resistance and a variety's ability to cope under stress have been fully on display. Some have coped and a lot have not.
Soil science, I would say is one of the most important factors governing yield, has been largely forgotten, farmers have devolved responsibility in many areas to their ag-chem supplier and crop walkers who supposedly are more knowledgeable in maximising yields and thus returns on their behalf. The knowledge gap on farm has been further diminished as a result of squeezed margins in the 'naughties' that lead to farmers farming more acres with less personnel and thus being more time restricted to chase knowledge in this regard. Universities and Agricultural Colleges too reduced the soil science input and concentrated more on the chemistry and machinery aspects of tillage, horsepower and technology as soil science generally was considered boring by most students. How many modern day farmers really understand and know what is going on in their soils?
A common theme I hear on farm is this; "why is it that with all your new fancy varieties you are breeding I am still only getting the yields we were getting 10 years ago"? Well, this time I heard an answer that came from a soil specialist company that has been growing a database on soils across the UK for the last 10 plus years and what he said was scary. The basis of it is this, pure arable farmers have been depleting the soil organic matter for so long with simple cereal and rape rotations that in some areas these levels are so low as to be irreplaceable, the soils have had all the life sucked out of them and as a result they physically are unable to provide the growing crops with the nutrients to attain their genetic potential.
It really has been noticeable in fields this year, those with good organic matter, good structure, good nutrient status have still delivered a reasonable yield and machinery has still been able to travel at critical times without leaving 3ft deep ruts. A farmer I know in Wiltshire has been chopping his straw for 10 years now, been applying copious amounts of compost and maintaining his lime and nutrient status with almost religious zeal. On very heavy clay over chalk, he has managed to keep going during harvest when his neighbours were getting stuck, his fields have a natural 'sponginess' to them as you walk them with very few areas of standing water in any of them, whilst neighbours have had 6" across whole fields of standing water for long periods of time. When you look where the combine has been traveling, there are no deep ruts, look over the hedge and it looks like a battlefield.
The genetic potential of some of the older wheat varieties like Einstein is well in excess of 25t/ha, we know from data attained in New Zealand these varieties are currently doing 18t/ha on farm in places consistently where the fertility of the soils has been maintained and the soils well managed in terms of rotation, organic manure levels, trace element replacement and most importantly, soil structure. These farmers have good rotations with break crops designed to replace organic matter and recharge the soil nutrient levels, instead of relying on stuff out of a bag. UK farmers in the main have not been doing this and yield increases have largely flatlined.
We need a radicle rethink in how we manage crop rotations, increase soil organic matter levels, improve soil structure and rejuvinate trace element levels. We need to sometimes stop and think; the soils we are farming are the product of millions of years in the making, yet with our modern cropping methods we are depleting their ability to produce the very food that our growing populations will need in the future.
How are the future generations of young farmers going to produce a decent crop that provides an economic return if the very medium needed to grow it is barren? Those who think GM will gallantly ride to the rescue are sadly going to be disappointed because the focus in GM at present is geared towards mainly chemistry, rather than soils.
The last 5 years have in the main been benign to cereal varieties, yes there has been pressure from disease, but the weaker ones were still able to deliver a credible yield with a lot of ag-chem help. This year we hit chamber six and it has blown a huge hole in many a bottom line Lets hope this year the HGCA clamps down on low disease threshold varieties whose presence on the list now is very questionable and we move away from 'spray and weigh' varieties.
