Main subject - sept/oct 2007   Improving Seed Performance Leopoldo Baudet lmbaudet@ufpel.edu.br Fabrício Peske In the July/August 2007 edition of SEED News, Prof. Peske wrote an article "Improving perception of seed value", which included a graph describing the different costs responsible for the final prize of soybean seed in Brazil. The aim was to show the array of different technologies available to the grower at the time of executing a rather simple task: place the seed in the soil and ensure that is completely covered. These different technologies involve the seed in the first place, which should be of high quality, as well as the application of products such as fungicides, inoculants, film coating, micronutrients and insecticides, among others. Table shows that to take the maximum advantage from these technologies the grower has to be certain that the seed complies with high standards and that the different products were applied properly, in concentration and distribution along the seed surface, so that they can effectively accomplish their function. In any business there's a time for investments, a time to collect the revenues and the seed is the best example to this, since the beginning of time. However, the arrival of the different technologies that transformed agriculture has reinforced this concept. The use of high quality seeds which grant a good performance is widely acknowledged by farmers as one of the most effective means to minimize costs and risks. Once every possible measure has been taken to produce quality seed, the farmer can further increase their performance through the improvement of conditions at planting and in the environment that surrounds the seeds. The improvement on seed performance will come through special treatments, processing and procedures to improve conditions at planting. High technology strategies to match the farmer's expectation on crop performance The seed of many species (soybean, cotton, hybrid corn, rice, vegetables and flowers) is currently subjected to intense competition as a result of the acknowledgement by growers of the importance of seed quality and that any failure in uniformity of germination and emergence will eventually prejudice the product's image. The different alternatives that are being implemented to improve seed performance involve covering them with specific products to deliver protection through an extended period, pre conditioning (osmotic or hydric) or seed priming, the enhancement of processes such as germination and emergence beyond their genetic potential and the enhancement or alteration on seed physical properties that determine its planting capacity. Finally, the application of biochemical treatments such as growth regulations can deliver uniformity and speed of germination and seedling emergence. Thanks to the seed covering products, it is now possible to stick to the seed powder products as well as liquids and forget about the traditional seed treatments, but rather think of which and how many of the different products we are going to incorporate on the seed. This means not only protecting the seed from any potential pathogens present in the soil or carried by the seed itself, but enhance her with micronutrients, hydrophobic products or even hormones. All these possibilities gain further relevance when the seed in question is of high value, which is the case for hybrids from rice and corn, vegetables and flowers in general, species in which a low percentage of dead seeds or seedlings imply significant losses when we consider their role on the potential population and productivity. Several experimental results show that a small investment on seed treatment relative to the seed cost not only improves the performance on germination, emergence and seedling health, but also has an enormous impact on the level of production per hectare. For rice, the treatment with insecticides has boosted yields by as much as 713 kg/ha, while in vegetables the application of fungicides to the seeds has reduced the incidence of damping-off in pre and post emergence by Alternaria, Pythium, Phytophora and Rhizoctonia. In the forage grass Brachiaria, the addition of hydrophobic products to the seed ensures that they will germinate only when sufficient soil moisture is available, avoiding the germination waves caused by occasional precipitations. Each crop, cultivar or even region can demand or need a different seed treatment. For soybean and corn, the treatment with insecticides amounts to 12 to 22% of the seed cost, since it may be just the only kind of treatment to effectively reach specific soil pests, thus increasing grain yield in up to 128%. When considering hybrid corn and hybrid rice, the situation is even clearer, since planting rates for these species are lower than for conventional cultivars and the seed has an inherently higher value. Aside from the traditional treatment with fungicides (either systemic or contact) or insecticides (chemical or biological), treatments with giberellic acid (growth regulator) in rice seeds and lettuce, and with hydrogen peroxide in seeds of soybean, sugarbeet and common bean, have been reported as enhancing seed performance by improving germination and seeding emergence. See components costs of various crops in Brazil page 2 ->> Improving Seed Performance