Dados do Trabalho

Título

SOIL CHEMICAL ATTRIBUTES IN LONG-TERM ONION NO-TILLAGE VEGETABLE SYSTEM

Resumo

The use of cover crops, essential for a no-tillage vegetable system (NTVS), modifies soil chemical attributes. This study sought to evaluate how different winter cover crops affect soil chemical attributes in the onion NTVS conducted for ten years. The work was conducted in an experimental area in the municipality of Ituporanga (SC) that has had onion NTVS since 2009. The treatments were black-oats (BO) (Avena strigosa) single, oilseed-radish (OR) (Raphanus sativus) single, BO+OR intercropped and fallow (weeds) in winter, followed by onion (Allium cepa) in spring and velvet-bean (Mucuna aterrima) in summer, in a randomized block design. After onion cultivation in 2010, 2015 and 2020 soil samples (0-10 cm) were collected for chemical characterization: pH (H2O), organic-matter (OM), P and K+ (Mehlich-1), Ca2+, Mg2+, Al3+, potential acidity, cation exchange capacity (CEC), base sum (SB) and base saturation. There was no difference among treatments, only in the years, except for K+ and Al3+ which did not differ between the factors and ranged from 224-760 mg dm-3 and 0-0.02 cmolc dm-3. In 2010 and 2015, pH increased from 5.6 to 6.3, P from 80.3 to 130.7 mg dm-3; Ca from 5.7 to 8.9 cmolc dm-³, CEC from 15.1 to 16.4 cmolc dm-3, base saturation from 68 to 79% and SB from 10.2 to 12.9 cmolc dm-³, and not differ between 2015 and 2020. From 2010 to 2015, there was a reduction in potential acidity (4.9 to 3.6 cmolc dm-3) and Mg2+ (3.2 to 2.7 cmolc dm-³), values were maintained in 2020. OM, P and Ca2+ decreased between 2015 and 2020, from 4.1 to 3.6%; 130.7 to 107.6 mg dm-3; 8.9 to 8.4 cmolc dm-3, respectively. The use of onion NTVS increases pH, P, Ca2+, CEC, V% and SB and reduces soil potential acidity from five years of management. The reduction of P and Ca between 2010 and 2015, is related to the non-practice of fertilization of the area due to the high nutritional contents found.

Palavras-chave

Allium cepa; Avena strigosa, Cover crops; NTVS; Raphanus sativus.

Instituição financiadora

AGRISUS, Capes, CNPq, FAPESC.

Agradecimentos

AGRISUS, CNPq, CAPES, EPAGRI, FAPESC, PPGRGV.