Effect of Planting Date on Fusarium spp. and Diaporthe/Phomopsis Complex Incidence and its Relationship with Soya Bean Seed Quality

Abstract

Fifteen soya bean genotypes from maturity groups IV, V and VI were planted on three dates at Manfredi Experimental Station – INTA, Córdoba Province, Argentina. Seeds were harvested at maturity and evaluated for seed infection by Fusarium spp. and Diaporthe/Phomopsis complex, and for physical and chemical parameters. There was a significant negative correlation between planting date (PD) and fungal incidence (P=0.05). A higher percentage of fungal incidence at earlier PD was consistent with lower seed weight and volume, higher oil content and no change in protein content. The highest values of fungal incidence were associated with increased oleic acid and decreased linoleic and linolenic acid contents. These results suggest that planting late maturity cultivars or delaying the planting of early and mid‐season cultivars may reduce seed infection by Fusarium spp. and Diaporthe/Phomopsis complex.

Effect of fungal damage by Fusarium spp and Diaporthe/Phomopsis complex on protein quantity and quality of soybean seed

“…An interaction between Fusarium spp and fungi of the Diaporthe/Phomopsis complex has been detected in many soybean growing areas from Argentina. 22 Those findings have been confirmed and, in addition, it was found that the fungi most frequently recovered were Fusarium semitectum, Phomopsis longicolla and Diaporthe phaseolorum var sojae. There were significant differences in field fungal incidence among the soybean genotypes studied.…”

“…There were minor differences in protein profiles between infected and uninfected seeds from FH 6686 cultivar. In a field trial, 22 this cultivar had reduced fungal incidence and severity. In this work, although the seed samples of symptomatic seed lots were chosen to obtain a 100% fungal incidence, it was noteworthy that fungal severity in the FH 6686 cultivar was lower than in the other two cultivars, resulting in a negligible degradation of the seed protein profile in the former cultivar.…”