Nitrogen effect on the productivity, physiological quality and characteristics of dry bean seed

The results of fertilizing with N on bean yield are questionable, and most of the works does not study the effect of the N on the physiologic seed quality and size (screen grading). The experiment was set out in São Manuel, SP, Brazil, in the agricultural year 1993/94, on a Yellow Red Latosol (Haplorthox) using bean cultivar IAC-Carioca, in randomized blocks design with four replications. The objective of this research was to study three rates of N (0,0; 12,5 and 25,0 kg ha-1) applied at seed sowing time, combined with the same rates broadcasted after seedling emergence. At harvest the following characteristics were evaluated: yield components (number of seeds per plant and one hundred seeds weight), seeds yield, percentage of germination, first counting germination percentage, germination speed index and electrical conductivy. There was no significant effect of the interaction of N applied at seed sowing times broadcasting. Applied N rates did not shown any favorable effects on seed germination and seed vigor. Supplying 25,0 kg ha-1 of N at sowing time increased yield components, without increasing yield. Availability of N, due to broadcasted fertilizer increased seed size.

Phaseolus vulgaris; mineral nutrition; seed quality; classification of seed

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