This section is coordinated by professors from the Federal University of Pelotas/Brazil, with the aim of answering enquires sent by the readers. Send your questions to

    I found very interesting the central matter of the last SEEDnews, covering the seed drying with dehumidified air by cold. In this sense, I wonder if this type of drying may be used for bean, as in the traditional models there is a risk of gases or smoke of altering the culinary qualities of the bean.

    The drying with dehumidified air by cold can be used for any species, not changing the physiological seed quality and neither the culinary or industrial qualities of the grain. It is a technological innovation that facilitates the drying process with more precise temperature control, only modifying the physical properties of the air.

    I got into the soybean seed business recently, and for this growing season, which begins in October, I will be acting in order to meet the farmers’ complaints about seed quality. Knowing that the task is difficult, I would appreciate to have some guidance on how to proceed.

    In Brazil, 25 million hectares are cultivated with soybeans, and from these, around 16.7 million are grown with seeds that farmers purchase. As we know, not every seed will produce a new plant, and in some cases, there will be the need to replant the field, and when this occurs, the farmer will complain about the seed quality and then check other causes. At this point, it comes the experience and knowledge from who sold the seed. The best suggestion is to know the quality of the seed that we are commercializing and have the records in hands, in order to be able to adequately argue with the farmer.   

    I have heard and read that the production of hybrid rice seeds is difficult, and the production fields, when properly handled, exhibit less than 40% of the production of hybrid F1. Could you comment on this?

    For the production of rice hybrid seeds, two parents are used - one that serves as female and the other as male. The female plant is male-sterile and, for forming the seed, it will receive pollen from the male, being this process fairly critical, because  it will depend on the timing of maturation of the male pollen with the mother stigma. In addition to this factor, there are others such as air speed for the pollen transporting, opening of the palea and lemma from the mother plant, plant height, among others. Thus, the productivity of the production fields of hybrid rice seeds is usually considered low.

    I have attended some meetings where it was talked a lot about patent and plant variety protection. In this sense, I wonder if you could clarify me if a plant breeder may use in his breeding program a patented material.

    There are several ways to protect a material, the most common being the plant variety protection act and the patent law. In the plant variety protection act, it is contemplated that the plant breeder can use in his breeding program any commercial material protected by this law and use it for research and possible commercialization. On the other hand, in the patent law, the plant breeder does not have the freedom to use a patented material in his breeding program (only for research in some countries like Brazil). This means that only after the patent finishes after a few years, is that a patented material will be available for sale in its generic form.

    I have been buying seeds for many years and one of the first things I do, as soon as the seed arrives, is to look assurance certificate, in order to see the germination percentage of the lot. I have observed that lots with the same germination have different performance in the field, which, according to experts, it can be attributed to the vigor. So, I wonder if it is also possible to do a vigor test in the seed lots for a better assessment of their physiological quality.

    There are several vigor tests that can be used, as the accelerated aging test, cold test, among others. However, using the vigor test as a commercial standard is difficult, mainly due to its expiration time, because the seeds tend to decrease its vigor linearly as the storage time increases. There are, at the present moment, strong academic and commercial discussions for a better use of the seed vigor information.



Receba nossas melhores
matérias em primeira mão!