Spatial analysis of soybean yield in relation to soil texture, soil fertility and soybean cyst nematode

摘要

The objective of this work was to study the spatial distribution of the soybean cyst nematode (SCN), Heterodera glycines Ichinohe, in relation to soil fertility (pH, P~+, K~+, Ca~(2+), Mg~(2+), and soybean yield spatial patterns in relation to SCN, soil texture and soil fertility. SCN was positively cross-correlated with soil pH within a range of 60-130 m, and negatively cross-correlated with Ca~(2+) up to a range of 110 m in Field B; the correlation was weaker in Field A. Yield was negatively correlated with SCN. Yield was strongly cross-correlated with soil texture (r(sand) = -0.89, r(clay) = 0.84), soil pH (r = -0.60), and Ca~(2+) (r = 0.60) in Field B (range = 130-140 m). We conclude that management zone delineation would be an appropriate strategy to overcome yield losses in fields where soil properties and SCN densities appear spatially structured and where SCN and unfavourable soil conditions pose a strong influence on yield spatial variability.