Fusarium – Problematik bei Körnermais (Zea Mays L.)

In the last few years in maize stalk and ear rots caused by fusarium spp. was increasing, often causing contamination with mycotoxins. Most prevalent was fusarium graminearum, mainly producing Deoxynivalenol (DON) in kernels and stalk. DON is suspected to cause several diseases in humans and livestock. In our study, injection of conidial suspension in the silk channel was the most successful method for artificial inoculation. Due to significant differences between several hybrids, it could be concluded that resistance against the fungus is genetically controlled. Intensity of resistance is varying extremely, depending on environment. The mycotoxin concentration of the kernels was positively correlated with percentage of visible infected kernels, obtaining levels up to 95?ppm. Susceptible hybrids even showed in the rest plant extremely high levels of DON (up to 60?ppm). Naturally infected plants showed high mycotoxin concentrations above and below the main ear, exceeding the recommended level of forage for cattle. High mycotoxin levels in kernels and rest plants show the importance of resistance breeding against fusarium.     

Nitrate and Phosphate Leaching under Turfgrass Fertilized with a Squid-based Organic Fertilizer

Consumer demand for cleaned squid generates a substantial amount of waste that must be properly disposed of, creating an economic burden on processors. A potential solution to this problem involves converting squid by-products into an organic fertilizer, for which there is growing demand. Because fertilizer application to lawns can increase the risk of nutrient contamination of groundwater, we quantified leaching of NO₃–N and PO₄–P from perennial ryegrass turf (Lolium perenne L.) amended with two types of fertilizer: squid-based (SQ) and synthetic (SY). Field plots were established on an Enfield silt loam, and liquid (L) and granular (G) fertilizer formulations of squid and synthetic fertilizers were applied at 0, 48, 146, and 292 kg N ha⁻¹ year⁻¹. Levels of NO₃–N and PO₄–P in soil pore water from a depth of 60 cm were determined periodically during the growing season in 2008 and 2009. Pore water NO₃–N levels were not significantly different among fertilizer type or formulation within an application rate throughout the course of the study. The concentration of NO₃–N remained below the maximum contaminant level (MCL) of 10 mg L⁻¹ until midSeptember 2009, when values above the MCL were observed for SQG at all application rates, and for SYL at the high application rate. Annual mass losses of NO₃–N were below the estimated inputs (10 kg N ha⁻¹ year⁻¹) from atmospheric deposition except for the SQG and SYL treatments applied at 292 kg N ha⁻¹ year⁻¹, which had losses of 13.2 and 14.9 kg N ha⁻¹ year⁻¹, respectively. Pore water PO₄–P levels ranged from 0 to 1.5 mg P L⁻¹ and were not significantly different among fertilizer type or formulation within an application rate. Our results indicate that N and P losses from turf amended with squid-based fertilizer do not differ from those amended with synthetic fertilizers or unfertilized turf. Although organic in nature, squid-based fertilizer does not appear to be more—or less—environmentally benign than synthetic fertilizers.