Fenologia e acumulação de nutrientes por cebola de dia curto em semeadura direta

Growth and Nutrient Accumulation and Export in a Short-Day Onion

“…Number of leaves is a phenological characteristic that can be used instead of DAS to monitor plant development over time. It can thus be used to plan nutrient distribution during growing seasons and in regions where environmental conditions affect the duration of the growing cycle (MORAES et al, 2016).…”

“…The period of highest requirement (0.61 g plant -1 ) was from 70 to 144 DAS, equivalent to 84% of the total ( Figure 3A). K has also been reported to be the most accumulated nutrient for the short-day onions 'Optima' (0.27 g plant -1 ), 'Superex' (0.29 g plant -1 ), 'IPA 11' (0.42 g plant -1 ), and 'Texas Grano 502' (0.79, 0.80 g plant -1 ) and the long-day onion 'Alfa Tropical' (0.24 g plant -1 ) (PÔRTO et al, 2006;2007;VIDIGAL;MOREIRA;PEREIRA, 2010;AGUIAR NETO et al, 2014;MORAES et al, 2016). The data for K accumulation varies widely in the literature and the present study (0.27 to 0.80 g plant -1 ) between genotypes and cultivation conditions, thus emphasizing the importance of studying DM and nutrient uptake.…”

“…The highest estimated accumulation was 0.14 g plant -1 ( Figure 3A). S was also the fourth most accumulated nutrient for 'Superex' (0.07 g plant -1 ), 'Alfa Tropical' (0.07 g plant -1 ), and 'Aquarius' (0.17 g plant -1 ) (PÔRTO et al, 2007;VIDIGAL;MOREIRA;PEREIRA, 2010;MORAES et al, 2016). The maximum requirement began at 75 DAS and remained constant until harvest.…”

“…Ca accumulation also increases until the end of the cycle in the genotypes 'Alfa Tropical' (0.09 g plant -1 ) and Texas Grano 502 (0.24 g plant -1 ) (VIDIGAL; MOREIRA; PEREIRA, 2010; AGUIAR NETO et al, 2014). Ca accumulation, however, tends to stabilize at the end of the growing cycle in 'Optima' (0.15 g plant -1 ), 'IPA 11' (0.53 g plant -1 ), and 'Aquarius' (0.26 g plant -1 ) (PÔRTO et al, 2006;AGUIAR NETO et al, 2014;MORAES et al, 2016).…”

“…Some information is available about the accumulation of nutrients by hybrids and open-pollinated onion cultivars in Brazil, from studies with hybrids Optima (PÔRTO et al, 2006) and Superex (PÔRTO et al, 2007); the cultivars Alfa Tropical (VIDIGAL; MOREIRA; PEREIRA, 2010), IPA 11, and Texas Grano 502 (AGUIAR NETO et al, 2014); and recently the hybrid Aquarius (MORAES et al, 2016) and the cultivar Bola Precoce (KURTZ et al, 2016). The results of these studies, however, indicated large differences in the quantities and proportions of nutrients accumulated by the plants due to the genotypic variations of each cultivar, environmental conditions, and yield increase (FERNANDES; SORATTO; SILVA, 2011).…”