By David Jones, Broad Acre Agronomist
As harvest gets into gear around Timau, I decided to ask local farm manager Daniel Moore to share his thoughts in this week’s THINK AGRONOMY on Farm Saved Seed and how to make it a success. Producing your own seed can save you money if done correctly, but can cause real problems without the right approach. Daniel has extensive experience in managing machinery and harvesting, and uses our Agronomy Service to fine-tune his decision making.
Firstly what is Home-saved Seed?
Seed which has been saved from a previous commercial crop with the view of planting and producing another crop.
Seed is one of the largest production costs of any arable farming system. It is claimed that you can save over a quarter by home-saving compared to buying first generation seed also known as C1 seed. With this in mind it’s understandable that us as farmers home-save seed in order to cut production costs and increase profitably of our businesses.
So Why Would We Not Home-save Seed?
There are two main reasons why home-saved seed may not be such a good idea, low vigour and carry over diseases, these problems increase in probability the older the generation of the seed.
Low Vigour is defined as a general lack of “energy” from the seed/ crop, this can show itself in many different forms throughout the growth stages of the crop. Firstly low vigour can be seen at the germination stage, as a decreased percentage of seeds germinating resulting in a bad stand for the rest of the season. Next it can be seen as a susceptibility to stress like nutrient deficiency and drought (very appropriate for the last few seasons). Slow growth can also be the result leading to more disease pressures. Overall a low vigour can result ultimately in a poor yield and low quality, potentially costing you more money than you saved (see gross margins below). C1 hybrid seed is practically prone to low vigour and shouldn’t be home- saved.
The top theoretical gross margin shows a crop grown with C1 seed bought from a merchant. The bottom gross margin shows the home-saved equivalent with a saving of a quarter of seed cost, in this case 1500ksh/ha ($15/ha). For the purpose of this demonstration the home-saved seed performed 0.1t/ha worse than the C1 seed after several years of home-saving, with even this small reduction of yield it reduces the margin by 2000ksh/ha ($20/ha) greater than you initial saving.
Carry over diseases are often a problem with home-saved seed. The picture on the right shows a crop grown from home-saved pea seed on a fixed four crop rotation over a period of 10 years to reduce soil borne Fusarium, with this in mind it led us to believe that this was a seed borne Fusarium which the labs later confirmed. Seed borne Fusarium can also lead to further disease infections such as seed rot, seedling blight and root rot damaging yield further and spreading throughout the field. Furthermore the pathogen can stay in the ground and infect future crops. It is recommended that you send your home-saved seed for pathogen analysis.
Note- It is worth bearing in mind that the longer you home-save a particular variety the further away your crop becomes from the original variety you planted, losing desirable traits and disease resistance effectiveness. Leaving you asking yourself is this even the same variety?
Decreasing your chances of problems when home-saving.
In an ideal world you would refresh your seed every four or five plantings with fresh C1 seed from the seed merchants. You can then start the cycle over again and hence minimising your chances of occurring problems. Obviously this is not an option for everyone due to the price implications.
How to successfully home-save seed if buying new seed is not an option.
1) Pick an area of the field from planting and give it special treatment, some more trace nutrients or an extra fungicide/ herbicide when required. Avoid including headlands as these often harbour more disease and weed pressures from the field margin and spray misses. In the case of cereals, make sure it is a first cereal after a break crop to avoid volunteer contamination.
2) Apply an ear fungicide at early flowering in cereals to protect the crop from ear diseases.
3) Try to harvest your seed crop when the crop is dry between (12%-15% moisture for cereals). Avoid drying as over drying a crop can damage the seed effecting germination in the next crop. (It’s worth noting that seed exposed to an atmospheric relative humidity of over 90% can cause grain to increase in moisture to over 20% moisture even if the crop was dry when but into storage. Under these conditions the seed loses viability and vigour.)
4) If tramlines are still green at harvest, leave them. Cut them separately at the end to avoid contaminating the sample with green grains. DO NOT APPLY GLYPHOSATE TO A SEED CROP PRE HARVEST – germination may be unaffected but seed vigour can be.
5) Inspect the seed looking for any abnormalities which could indicate disease or pest problems which may have occurred whilst growing or in storage. Ensure that the seed is of a good and even size, research carried out in the UK by AHDB has found that Canola seed size has a greater impact on vigour than whether the seed is Hybrid or Conventional.
6) Do a germination test before planting the seed to assess vigour. This can easily be done on farm with a tray of soil and a sample of the seed, plant the seed and water leave for a few days until a good germination appears remembering to water throughout. Then count the amount of seeds that have germinated compared to those which haven’t. A good germination result is above 95%.
7) Send your seed for a pathogen test to reduce disease carryover such as fusarium.
8) Make sure to dress the seed with an appropriate product for your situation to give it a good start.
David Jones is the Broad Acre Specialist at Crop Nutrition Laboratory Services Ltd. (CROPNUTS). David has a keen interest in soils and no till farming systems where he has undertaken work looking into weed levels and changes in soil structure, and has extensive experience in field trials and in the development of precision farming techniques. In his spare time he enjoys playing rugby.