Broccoli growth and nutrient accumulation
Single-head broccoli production has been increasingly popular among Brazilian olericulture farmers, although there is still little information regarding its nutrition. The aim of this paper was to study dry matter and nutrient uptake rate in single-head broccoli. The experiment was conducted during the period from March to May 2006 in Itatiba, SP, Brazil. The experimental design was completely randomized, with four repetitions. Plant samples were taken at 15, 25, 35, 45, 55, 65 and 75 days after transplanting (DAT), in order to determine leaf, stem and inflorescence dry matter and nutrients in each period. The plant had slow growth until 35 DAT, with little dry matter accumulation, increasing afterwards until the end of crop cycle. The largest dry matter accumulation occurred between 45 and 55 DAT, with an estimated increase of 2,068.75 mg plant-1 day-1. Nutrient absorption followed the plant dry matter accumulation curve. From its formation, inflorescence becomes the main sink of all nutrients in the broccoli plant. Accumulated nutrients, in decreasing order, were N > K > Ca > Mg > S > P > Fe > > Mn > Zn > B > Cu, respectively.