As soon your seed is harvested its time to think about getting it tested, the earlier you test the better! I can say this with complete confidence, as an analyst offering routine analysis to the Canadian seed industry I have had the opportunity to study the behavior of seed and the business needs of seed growers and merchants. Seed physiologists will tell you that seed is at its peak within hours of being harvested and it begins to deteriorate as soon as it goes in the bin. Germination can remain fairly constant if all the stars align, but the vigour will change very rapidly.
There have been numerous articles about early testing and especially given the challenges with harvest this season it’s recommended that a germination test be the first item on your agenda. Germination is fundamental in establishing basic seed quality. Early reports were indicating that the quality was quite good in some regions, however some areas are reporting frost and others a high incidence of disease across the Prairies. Regardless, every region is different and it is important to consider what your seed quality is like on a regular basis to determine how stable the germination is now, in effect a preliminary germination test after harvest is key, and testing later after cleaning will assist in establishing how well it will store for next spring.
I often refer to our tool kit these are the various tests that make up a complete package of tests that will give you the entire quality picture. The most important tests in the beginning are germination and vigour. There are many attributes to consider when we think of seed quality, and we refer to these as building blocks that are required to obtain a complete diagnostic profile on your seed lot. The diagnostic profile and complete package can be done at a later stage after you have had your preliminary work done. There is no point investing in a product that has issues that are apparent in the beginning.
Let’s start at the beginning.
A preliminary germination is worth every penny. Germination is the foundation upon which you should base your storage, treating, sales and later on seeding plans. It is most certainly one of your most economical inputs that should be considered as a return on your investment. An accredited germination will provide a sound result and should give you an indication of the seeds physical quality.
After the seedlings have been evaluated the first category is the normal seedlings. These are seedlings that will withstand normal seeding conditions. Keep in mind a germination test is designed to get the best result from your seed, optimum conditions in the growth chamber equals optimum output because no stress is imposed on the seed.
Next we evaluate the abnormal seedlings. There is a lot of information gleaned from how the seed presents itself and each crop is different. There are many individual symptoms that will indicate that there has been some sort of detriment and I will concentrate on some of the more important ones in the paragraphs to follow. In reality there are numerous situations that we encounter and a good seed analyst could almost write the book on your crop history without you telling us anything up front.
This season there are four key factors that are affecting the quality; frost, immaturity, mechanical damage and disease. All of these can really hurt the seed quality and longevity of your product regardless of crop type.
Frost for example affects the cell membranes and overall structure of the important growing parts of the seed, often into the embryo. In some cases this year for example faba bean seeds are black which is a good indication that frost was the cause. Frost is easy to decipher in cereals it will have a white cast or blistering on the seed coat, but sometimes its does not affect the appearance. It is best examined after germination as the seedlings will be shredded and tattered, often dead. However the symptoms of frost although very apparent in early testing can over time continue to disrupt the cells and cause the germination to drop. In this case it’s important to test periodically throughout the winter, or source new seed right away.
Immaturity, this phenomenon presents itself as an “unripe” seed. In canola it is seen as green seed, and in cereals it will be small, shriveled and discolored. The seed in germination will have symptoms of dormancy. Green seed in canola is very undesirable; it will affect the oil quality as well as affect the germination. Green seed can ripen if it’s almost mature, and in most cases it can be cleaned out because it is generally smaller. It’s a well known fact that green seed will deteriorate a lot quickly so it’s important to make sure the germination is well above 90%. Green seed lacks vigour and is often dormant or dead.
In cereals immaturity is commonly described as dormant and if the seed is close to ripe it can be overcome with gibberellic acid or potassium nitrate as a growth promoter. This is administered during the germination period, a pre-chill period is also provided to break the dormancy. Most shriveled or undersized grain is cleaned out so knowing what you have prior to cleaning is a good start.
Mechanical damage is seen predominately in large pulses and beans. The seed has been harvested when the moisture content is low, combine (cylinder) speed and auguring also compound the problem causing a dry seed to either break internally, crack its seed coat or split in half. The seedlings will be malformed either lacking a root or a shoot or both, again mechanical damage can affect the entire lot, and the vigour will almost certainly be compromised.
DISEASES AND PATHOGENS
There is a plethora of diseases that we encounter today but we are also much more knowledgeable about the effects of certain pathogens and the diseases they cause. In fact a complete disease diagnostic can determine the level and type of infection that is present. Diseases are often observed in the germination test and although the analyst can not identify it, they do have a very good idea of the severity and impact on quality. In this case the seed lot is offered forward for further testing by a qualified pathologist or molecular scientist.
These symptoms mentioned above need to be noted on the report of analysis as they do impact the overall quality and outcome of your product. So please remember to study your report of analysis for all the information you need because you can determine early on what you need to be thinking in terms of sourcing new seed or the longevity of the germination.
Adding a vigour test that will stress the seed further is an excellent resource. Vigour is a predictor of performance under a wide range of storage and field conditions. A combination of germination and vigour is a match that will save you a lot of leg work later on.
Seed testing is a crucial element in your farm operation and by using a simple germination and vigour test this will reveal all the magic the seed has to offer.
These tests have more potential than most people realize. It’s disheartening as often seed testing is overlooked, especially if it is bin run and the farmer wants to use it for himself, or simply if the seed ‘appears to look good’. I have heard all too often that seed has gone into the ground without a scrap of information about its potential performance. That’s like choosing the wrong fuel for a high performance car. It is not a practical business decision given the costs that are associated with equipment, fuel, fertilizer and the seed to move along without testing one or more elements.
In years where environmental factors have played the role in affecting quality it is also important to put a sample aside for testing and reference. Always keep a small bag on the farm as a bench mark. Also remember that accurate sampling is critical in obtaining a representative sample.
20/20 Seed Labs Inc., has researched and developed tests over the years that are commercialized for routine use. These tests have been designed to compliment the standard recognized accredited tests and when used together provide a powerful information package.
After successfully testing your seed for a germination and assuming the quality is good, you should consider the vigour test, a 1000 kernel seed weight, and a complete disease profile. Once you have all the information and you are satisfied that the quality is within an acceptable range you should use a recommended seed treatment.
Technology today is more powerful than it has ever been and techniques within seed testing are becoming more sophisticated, we have the knowledge to arm you with every angle you need to produce a good stand with excellent yields. Use your seed lab for valuable information as early as you can.
20/20 seed Labs Inc is a private independent seed testing laboratory that has established a brand for excellence in determining seed quality through routine analysis and molecular testing. In addition we have a full compliment of qualified seed analysts and experts who can consult you on your results or make recommendations about the type of testing that you need.