Production and subsequent sowing of soybeans enriched with molybdenum: physiological quality, chemical and nutritional changes and application times

Abstract

Soybean (Glycine max (L.) Merrill), as well as other crops, need nutrients to grow and reproduce, and studies have shown the importance of the use molybdenum in soybean crops, where this has great importance in the process of symbiotic fixing nitrogen. Thus, the study in question will aims produce soybeans seeds enriched with molybdenum doses, in accord with the micronutrient applied on the culture, and verify the behavior of these seeds as their nutritional and physiological quality, besides use these soybeans enriched with molybdenum for sowing in next crop, and analyze their behavior as the presence and absence of molybdenum at the beginning of culture. The experiment is being developed in the Education Farm, Research and Extension/UNESP - Campus of Ilha Solteira, located in the Selvíria - MS (51° 22'W, 20° 22'S, altitude 335m approximately), in an Oxisol alic and texture loamy. The experiment will be conducted in two years, and will use the cultivars BRS Valiosa RR, in both years, being that, in the first year will be used three doses of molybdenum, with four repetitions. The doses of molybdenum will be 0, 400 and 800 g Mo/ha, and will be applied neither on leaf, in two applications, half in the stadium R3 and half on R6. In the second year the seeds obtained in the first year will be sown for the formation of two experiments that will be conducted in parallel, where an experiment is performed three application methods, with four replications. The application methods are: without application of molybdenum, molybdenum application at the time of sowing at a dose of 25 g Mo/ha, and foliar application at the V4 stage at a dose of 25 g Mo/ha. The second experiment will follow the 4 x 4 factorial (times application x doses) with four replications. Will be held four times of application: V4, pre-flowering, in R3 and R5, as described by Fehr et al. (1971), and the doses used are 0, 25, 50 and 100 g Mo/ha. The following evaluations will be conducted in the first year: plant population, agronomic characteristics, 100 seed weight, seed yield, molybdenum concentration in the seed, physiological quality (% germination, first count, rate of emergency, accelerated aging and conductivity) and nutrition (protein and oil content) seeds. For the second year, evaluations will be: final stand, agronomic characteristics, yield, vigor, and to evaluate the leaf nutrients and number, and dry weight of nodules per plant. (AU)