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 Enquiries SEED News - jan/feb 2006
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This section is coordinated by the professors from the Federal University of Pelotas-Brazil, with the objective of answering the inquiries sent by the readers.
Send your question to e-mail: silmar@seednews.inf.br
We know that the germination test is performed by providing seeds with ideal conditions for their germination, such as water, temperature, and light. In this sense, I would like to know if it is possible to obtain an emergence result that is superior to the ones from germination?
Under normal circumstances, germination is always equal or higher than the emergence in the field. Nevertheless, there are instances in which emergence can be higher, as for the case of soybeans seeds with Phomopsis. It happens because the pathogen is in the seed coat and, when it emerges, it leaves the coverage on the soil and the microorganism is left with it, making seed performance easy. In the germination test on paper towel, the tegument does not detach easily from the seed, affecting its performance.
I liked seeing the cost table for the ones who buy GM seeds related to those who use their own material for sowing. However, I could not quite understand the bonus a farmer gets for purchasing seeds when he sells his soybean as grains. Could you explain?
The table applies to transgenic soybeans, relating production costs by means of a technological tax payment over the RR soybean event. In Brazil, in the agricultural year of 2005/06, the cost for those who use seeds is close to 1%, while it is 2% for those who use their own material. The charge of a technological tax, for those who buy seeds, is effected by means of the seed producer, while for those who do not buy seeds the payment is done upon grain selling. Specifically on the bonus, it is a quantity of grain per hectare that the farmer, who bought the seed, will be prevented from paying the technological fee, which in our case is 69kg for each kg of seed that was bought.
I am experienced in hybrid maize, which really produces much more than the varieties, mainly the ones indicated for high technology. In this sense, I would like to know what is the inconvenience in using the seed more than one time?
The main inconvenience is the decrease in productivity, which can reach more than 30%, because it reduces the heterosis (hybrid vigor) of the material. The other inconvenience is the lack of uniformity from plants, cobs and grains, affecting the commercial product. In synthesis, make savings on seeds is a guarantee of loss. For illustration, maize varieties whose seeds are not produced using the technique of half-brothers, reduce their productive capacity due to auto-fecundation. The same occurs with hybrids (there is also a tax of auto-fecundation for them).
I would like to enter the seed analysis business and for that what are the requirements, beyond trained staff, physical space, and equipments?
Seed analysis laboratories must be certified at an entity, which can be the government or an association (as ISTA International Seed Testing Association). As mentioned, the certification involves several items, but there is one that deserves special attention, which is having a quality system. In Brazil, for domestic market, it is requested to have the quality system ISO 17 025, while for external market, ISTA has its own system, which is specific for seeds. Such requirement is relatively recent, and came to improve laboratory services.
I have been often hearing that a given seed category should not be sold to farmers. Could you please make your comments?
Usually the countries have four seed categories in the certification program, namely: genetic, foundation, certified I, and certified II. The first category encloses few seeds and in general, remains with the plant breeding personnel, the foundation is the genetic's daughter, and it is used for increasing seed quantity and this is normally used to produce the certified I that is distributed to seed producers and this is normally used to produce the certified, so that they can multiply it and so obtaining the certified II category, which is sold to the farmer. Such process is done for obtaining both seed quantity and quality at the same time. Genetic and foundation seed categories are very valued and not much to be directly sold to farmers.
I am preparing my driers to soybeans seeds that is near, and I intend to increase my drying capacity; for that I would like to know what is the maximum air temperature that can be used?
For your intermittent drier, with static capacity of 25 tons with 40 minutes-seed turns, it is recommended to start the drying at 50 °C air temperature, increasing up to 60-65 °C after one hour. With this air temperature, the seed must be with less than 40 °C in the end of the drying process (12-13% moisture) - a temperature that does not affect the seed.
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