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Field experiments were conducted over 3 years to assess the effects of fungicides (F) containing strobilurins (alone and in mixture with morpholine, triazoles) and triazoles (epoxiconazole or propiconazole) on winter wheat ‘Zentos’ grain quality, incidence of Fusarium head blight (FHB) in the field, grain contamination with fungi and mycotoxins. The effect of strobilurins and triazoles on the parameters tested was more dependent on the weather conditions of the growing season than on the F applied. The incidence of FHB was low in 2002 and 2003, but high in 2004. Averaged data suggest that strobilurin treatments decreased the level of FHB. In 2002, grain contamination with fungi was lower than in 2003 and 2004. The data on the impact of fungicides on post-harvest grain infection with Fusarium spp. and contamination with mycotoxins deoxynivalenol (DON), zearalenone (ZEN) and T-2 were controversial. The fungicides only insignificantly affected protein and gluten concentration in grain, as well as sedimentation and falling number. All grain quality components were especially dependent on the year (significant at P<0.01). However, fungicide application significantly, at P<0.01, increased grain protein and gluten yields: they were higher for the strobilurin-treated plots (with a small exception) than for the untreated and those treated with propiconazole.
Gluten proteins composed of gliadins and glutenins are important contributors to the wheat quality properties. Twenty-eight winter wheat cultivars differing in bread processing quality were collected at the experimental fields of the Agricultural Institute Osijek, Croatia, in growing season 2006/2007.The HMW-GS composition and gliadin contents were determined by SDS-PAGE and RP-HPLC, respectively, with the aim to determine their relationship with wheat quality properties. Based on gliadins and HMW-GS data for 28 wheat cultivars PLS models were developed for the prediction of 15 baking quality parameters.NIPALS algorithm was applied for the evaluation of the latent variables and regression coefficient parameters. The obtained 4-th order models have average coefficients of determination R2=0.80.Determined variable importance in projections (VIP) coefficients revealed that HMW-GS data have the dominant influence on the baking quality parameters. For extensographic and farinographic properties the Glu-D1 locus has the main VIP coefficient while Glu-B1 locus is the most important for the indirect quality parameters. The derived PLS models and VIP coefficients could be used in molecular based wheat selection and breeding program.
The current study was focused on fungi colonizing the stem bases of wheat. Particularly, fungal species with significant harmful effect on wheat were studied. The dynamics of the stem base colonization by these fungi over the growing season were observed, and the association between individual pathogenic fungi was also evaluated. In addition, the fungal leaf sheaths penetration, which can cause physical disturbance, was assessed. The asymptomatic presence of fungal DNA in wheat tissue was confirmed. Microdochium nivale was found on the stem bases most frequently. Other fungi, such as Oculimacula spp., Rhizoctonia cerealis and Fusarium spp., were presented considerable less frequently. The statistical significant association was confirmed only between M. nivale var. nivale and M. nivale var. majus . Out of these, M. nivale tended to decrease in summer season, the frequency of occurrence of Oculimacula spp. and R. cerealis increased at later growth stages. Along with this, these species infected only plants previously colonized by M. nivale . Asignificant relationship between visual symptoms and presence of M. nivale DNA in the host tissue was confirmed.
In Hungary rice ( Oryza sativa L.) is cultivated under flooded conditions. Direct seeding into the soil is applied usually. The optimal sowing date is a key factor necessary to the success of this annual crop because of the relatively short growing season. The main objective of this research was to: (1) analyse duration of period from sowing to emergence at different temperature values, (2) determine base temperature of this phenophase and (3) establish a thermal time model for rice emergence. To do this, growth chamber experiments with 5 Hungarian cultivars were conducted to determine the time to median emergence (E 50 ) at constant temperature of 14 to 34 °C in 2 °C steps. The sowing depth was 2 cm, and moisture was not a limiting factor. It was found that the critical thermal zone, which is of highest practical importance, is between 14 and 16 °C. At these values the E 50 is 23.9 and 13.4 days, respectively, showing a border between unfavourable and acceptable conditions. In the temperature interval between 26 and 34 °C the time needed for emergence was only 3.3 to 4.4 days. Variety differences were also detected. Base temperature was found between 9.8 and 10.9 °C. The thermal time requirements of 4 cultivars varied between 69 and 73 °C day. Data of field experiment with 9 sowing dates and a pot experiment with 3 sowings confirmed that our thermal time model can successfully simulate the emergence of rice.
The present work analysed whether grain weight is affected by changes in source:sink ratio in twenty-four durum wheat cultivars from Italy and Spain released through the 20 th century grown under Mediterranean conditions. For this purpose, a field experiment was conducted during the 2002 growing-season in southeastern Spain. Sink strength was modified by removing half of the spikelets, of one side of the spike, one week after anthesis. Spikelet trimming had different effects on both average grain weight and individual grain weight at different positions within the spike. While old cultivars did not respond positively to spikelet trimming, and appear to be mainly sink-limited, intermediate and modern cultivars from Spain increased their grain weight in response to sink reductions, suggesting co-limitation by the sink and source. On the contrary, grain weight of intermediate and modern Italian cultivars remained relatively unchanged suggesting a sink-limitation to grain yield. The differential response to source-sink manipulations observed between Italian and Spanish cultivars could be attributed to their different genetic background, which determines their level of adaptation to harsh Mediterranean environments.
The field research was conducted on hypogley in Vrbanja, Croatia, during four growing seasons from 1992/1993 to 1995/1996. They included five soil tillage systems and three nitrogen fertilization levels in four replications for winter wheat ( Triticum aestivum L. ) after soybeans ( Glycine max L. ) as a preceding crop. Tillage treatments were: PL=conventional tillage (ploughing to 20 cm depth, diskharrowing and standard sowing); DS=diskharrowing and standard sowing; MC=tillage by multitiller and chisel, standard sowing; RS=soil tillage and sowing by RAU-Rotosem; PR=ploughing to the depth of 20 cm + RS. Nitrogen fertilization treatments were 140 (N1), 170 (N2) and 200 kg N ha −1 ) (N3). Wheat grain yields effects by tillage were as follows: 6.00 (PL), 5.79 (DS), 5.65 (MC), 5.61 (RS) and 5.90 t ha −1 (PR). Significant differences of yields were found only in the first year of testing. Nitrogen fertilization resulted by non-significant differences of yields as follows: 5.56 t ha −1 (N1), 5.85 t ha −1 (N2) and 5.96 t ha −1 (N3). The conclusion is that under certain environmental conditions it is possible to apply reduced soil tillage and moderate N fertilization.
The effect of the N, P and K fertilisation on yield and quality parameters of cultivar Žitarka during two growing seasons (2002/03 and 2003/04) was studied. Fertilization increased yield, although only treatment with 200 kg N ha −1 yielded significantly higher than treatments with 80 kg N ha −1 . Protein content increased significantly (P<0.001) with the application of 80 kg N ha −1 , 120 kg N ha −1 and 160 kg N ha −1 . The highest N applications with 200 kg N ha −1 and 240 kg N ha −1 increased protein content on the same level as with 160 kg N ha −1 . Wet gluten and sedimentation value were also significantly (P<0.001) affected by N fertilizer treatments. Although increment of N fertilization increased values of these quality parameters, 120 kg N ha −1 , 160 kg N ha −1 and 200 kg N ha −1 treatments showed similar effect, while treatment with 240 kg N ha −1 resulted with significantly higher values. Gluten index increased only with applying 80 kg N ha −1 while the highest N levels (200 kg N ha −1 and 240 kg N ha −1 ) showed dramatically gluten weakening. Considering grain hardness only treatment with 80 kg N ha −1 had significant (P<0.001) influence. Simultaneously, P and K did not affect grain yield and quality, neither comparing PK to controle, or N 2 P 1 K 1 to N 2 P 2 K 2 .
Winter barley were grown under field conditions during the 2004 growing season and residual influences of liming with carbocalk (waste of sugar factory) and phosphorus fertilization with MAP (monoammonium phosphate) were tested. By using the lowest lime rate (15 t ha −1 ) barley yield was increased by 30%. Overliming (90 t ha −1 ) resulted by significant yield decreases in comparison with application 15 and 30 t of lime. Using of 45 and more lime per hectare protein contents was significantly increased. In general, liming considerably influenced on grain composition of barley. For example, by application of the lowest lime rate, grain P, K, Ca, Mg, Fe, Cu, Mo and Na significantly increased in comparison with the control. Differences of grain composition among lime treatments were mainly non-significant. Ameliorative P fertilization significantly increased grain yields of barley up to 25% in comparison with the control. In general, grain composition differences among applied treatments were mainly non-significant because significant differences only for P and Mn (increasing trend due to P application) as well as for Zn and Mo (decreasing trend) were found.
Maize and soybeans were grown under field conditions on acid soil (pH in KCl = 3.99). The field trail was conducted in spring 2004 as follows: a = ordinary fertilization, b = a + NPK-1, c = a + NPK-2, d = a + NPK-3 and e = a + NPK-4. The fertilizer NPK 10:30:20 was source of P and K (using in amounts 416, 1249, 2082, 2916 and 3748 kg/ha, for the treatments a, b, c, d and e, respectively. Nitrogen amount was equilized for all treatments by addition of adequate quatities of CAN (calcium ammonium nitrate: 27% N) were used. The experiment was conducted in four replicates. By application of the ameliorative rates of NPK fertilizer, grain yields of maize significantly increased to level of 14% compared to standard fertilization (12.33 and 14.00 t ha −1 , for the control and the second rate of NPK fertilization, respectively. Only the highest rate of NPK fertilizer resulted by significant increase of protein in grain. Residual response of soybean (the growing season 2005) to the fertilization was considerably higher compared to maize, because yields of soybeans were increased up to 32%. Protein contents in soybean grain were independent on the fertilization, while oil contents were increased up to 0.66% compared to the control.
Five maize ( Zea mays L.) hybrids were grown for four growing seasons on gleysol characterized by moderate supply with potassium (K). Three rates of KCl were applied in four replicates at the beginning of April 2001 as follows (kg K 2 O/ha): 150 (control), 650 and 1400. The highest rate of KCl resulted in significant increases of yield of 14%, 24% and 12%, for 2001, 2002 and 2003, respectively; while in the fourth year similar yields to the control were found. The OsSK552 and Bc5982 hybrids (4-year mean 8.70 t/ha) were more susceptible to soil stress in comparison with OsSK444 and OsSK458 (mean 9.07 t/ha). At the same time, Florencia hybrid yielded 9.37 t/ha. Four hybrids responded similarly to applied fertilization (yield increases from 13 to 16% in comparison to the control), while Florencia had low response to KCl (yield increase for 5% only). Under these conditions we recommend combined solution using 1000 kg K 2 O/ha every third year and a choice of tolerant hybrids.
