Two isolates each of Fusarium moniliforme and Fusarium proliferatum isolated from maize were compared for growth and fumonisin B 1 production on maize, wheat, and barley extract agars and on irradiated maize, wheat, and barley grain in relation to water availability and temperature. Growth rates of both Fusarium spp. were similar or higher on wheat and barley than on maize extract agar. Regardless of temperature, all isolates produced fumonisin B 1 only on irradiated maize grain, but not on wheat or barley. This might be a reason for the low natural occurrence of fumonisins on those grains.

In field experiments conducted over 2 years, triticale was compared with barley, bread wheat and oats for its dual-purpose (forage and grain) capability.The effect of spring forage removal on grain yield ranged from small yield increases (in the triticale and barley genotypes that otherwise lodged) to a 53% decrease, and was dependent on species, genotype, stage of development when cut, and time for recovery before grain harvest. A key factor influencing grain yield after early cutting was the number of spikes that developed.The complete types of triticale were better than the one substituted type tested for dual purpose but, as there is variability among them, selection for good mixed aptitude is possible.The production of the best triticale averaged over 2 years 3 t of forage DM ha"' (with 684 kg of crude protein ha-') and then 4-3 t of grain ha~'. In this instance, neither the grain yield nor the number of spikes per plant were reduced after clipping, in spite of the fact that the shoot apices were removed.Plant height and lodging were reduced by a forage cut. In triticale, the number of days to heading was increased even more when the cut was late, but no effect was observed in barley.

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The influence of cutting stage on forage and grain yield and quality has been studied in three barley and one triticale varieties, using two sowing dates in each of two sites. When cut at the first detectable node stage (C.31), forage yield was almost double the yield at the pseudostem erect stage (C.30). Barley yielded more forage than triticale at both cutting stages. Both species had similar forage protein content, but forage fibre content was greater in barley than in triticale. Cutting at stage 30 reduced grain yield by about 11 % and at stage 31 by nearly 35 %. Barley and triticale had similar grain yield. Grain protein content was not affected by forage removal, but was significantly greater in triticale than in barley. The later the stage of cutting, the greater was the delay in heading date. Triticale was more responsive to environmental conditions than barley.

An index method was applied for groundwater risk estimation at national scale in Portugal.• Integrating N hazard and aquifer vulnerability was a useful approach for risk estimation and rating. • Reducing N leaching may not reduce the N contamination risk if the reduction in precipitation is high. • Index method predicted current vulnerable zones and additional hotspots.

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Tiger nut (Cyperus esculentum) is a very profitable crop in Valencia, Spain, but in the last years, part of the harvested tubers presents black spots in the skin making them unmarketable. Surveys performed in two consecutive years showed that about 10% of the tubers were severely affected by the black spot syndrome whose aetiology is unknown. Disease control procedures based on selection of tubers used as seed (seed tubers) or treatment with hot‐water and/or chemicals were assayed in greenhouse. These assays showed that that this syndrome had a negative impact on the germination rate, tuber size and yield. Selection of asymptomatic seed tubers reduced drastically the incidence of the black spot syndrome with respect to using seed tubers with severe symptoms (selection of healthy seed tubers was not possible because the causal agent is undetermined). Thermal treatment of seed tubers with severe symptoms reduced the number of unmarketable harvested tubers by half but was detrimental for the germination. Chemical treatments of seed tubers with severe symptoms decreased the incidence of the black spot syndrome about 40% for sodium hypochlorite and about 10% for hydrochloric acid, trisodium phosphate and the fungicide trioxystrobin.

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