Maize seed sown in cold soil during the first ten days of April will only produce a satisfactory stand if the hybrid chosen has adequate chilling tolerance and if the seed has high biological value (germination percentage, cold test) and is treated with a high quality dressing agent. The emergence date is influenced to a great extent by the heat sum, so only a small proportion of the considerable difference in the sowing date is manifested in the emergence date. Nevertheless, healthy plants emerging from early-sown seed have more rapid initial growth and development, as demonstrated by their greater shoot dry matter accumulation. It is not worth risking early sowing in heavily infected soil, with seed lots having poor germination ability, without adequate seed dressing, or with chilling-sensitive hybrids.
Twelve silage hybrids were included in field experiments in Martonvásár in 2007 and 2008 to compare the agronomic traits and chemical quality traits of leafy and non-leafy hybrids. The climatic data for the two experimental years differed considerably. The results reflected the differences in weather conditions. Thanks to the plentiful rainfall in 2008 the hybrids reached their genetically determined height (274.32 cm on average), while in 2007 the average height was only 238.03 cm. In both years a leafy hybrid was the tallest, while the shortest plants were non-leafy. The assimilation leaf area above the main ear was greatest for the five leafy hybrids in both years, with values of 0.35–0.45 m
per plant for conventional hybrids and 0.53–0.84 m
per plant for leafy hybrids, averaged over the two years. The larger leaf area in leafy hybrids could be attributed both to the larger number of leaves and to the fact that they were broader. The greatest ear mass per plant was produced by Mv Massil (198.66; 320.00 g), a leafy hybrid which also had the greatest leaf area above the main ear. In addition to large green mass (leaf, stalk), an ideal silage maize hybrid should also have satisfactory grain yield. Several of the leafy and non-leafy hybrids in the experiment gave favourable results. In the present experiment the highest starch content was recorded for a leafy hybrid, while the highest protein and oil contents were characteristic of early maturing, non-leafy hybrids. Nevertheless, three of the leafy hybrids had above-average protein content.
Some agronomical characters of twelve single-cross maize hybrids were investigated at five different locations in Hungary over a three-year period. The characters examined were individual plant production (total mass of the ears on a single plant), thousand-kernel mass, number of kernel rows, ear length, number of kernels per row, shelling % and the assimilating leaf area above the main ear. Among these yield components, the individual plant production, the ear length, the number of kernels per row and the grain-cob ratio (shelling %) were influenced to the greatest extent by the year, followed by the variety and the location. The greatest average yield was achieved by the tested hybrids at all five locations in 1997 (263 g/plant). The average yields in 1998 and 1999 were significantly lower (221 and 203 g/plant, respectively). The outstanding yields achieved in 1997 could be attributed to the favourable ecological conditions, which led to the development of secondary ears in Keszthely and Sopronhorpács. At the other three locations there was only one ear per plant, but these ears were longer than in the following years. The greatest year effect was recorded in Sopronhorpács, where the individual plant production amounted to 305 g/plant in 1997 and 238 g/plant in the worst year, 1999. In Gyöngyös conditions were very dry in all three years, so the year effect was least pronounced at this location (grand mean of 195 g/plant in 1997 and 201 g/plant in 1999). Stability analysis was carried out using the coefficient of variance for individual plant production. Hybrids Mv 3, Mv 5, Mv 9 and Mv 12 were found to have the best adaptability. The shelling % was not significantly influenced by the location; the grain-cob ratio is relatively stable for maize hybrids. A correlation was found between the individual plant production and the leaf area above the main ear (R2=0.658). Hybrids with the largest leaf area above the main ear also had the greatest ear mass.
Authors:Z. Hegyi, Z. Zsubori-Tóth, J. Pintér, and C. Marton
Experiments have been underway in Martonvásár for many years to develop leafy silage hybrids, which have a greater aboveground mass than conventional silage hybrids. The best hybrids for biogas production would be those that produce a large quantity of biomass and are rich in starch. The chief characteristic of leafy hybrids is that they have more leaves than normal hybrids. Due to this enhanced leaf area above the ear, the vegetative period of leafy genotypes is shorter, while the grain-filling period is longer, which has a positive effect on both yield and grain quality. The results of the present experiment show that during the anaerobic fermentation of the silage, leafy hybrids produced more biogas (640 l per 1000 g dry matter) than conventional hybrids (606 l per 1000 g dry matter). There were no significant differences between the methane contents of the leafy and non-leafy hybrids tested in the experiment. A strong positive correlation was found between biogas yield and the starch content of the silage, and a moderate positive correlation between biogas yield and the sugar content. The correlation between biogas yield and the lignin and protein contents was negative, in accordance with other literary data.
Authors:Z. Tóthné Zsubori, I. Pók, Z. Hegyi, and C. Marton
Leafy hybrids represent a new direction in the breeding of silage maize. Not only does the increased number of leaves above the ear in these hybrids lead to an increase in dry matter production, but the large quantity of carbohydrates formed and stored in the leaves results in silage with better chemical quality. Many papers have been published abroad on this subject, but few data have been reported in Hungary.The present work aimed to examine the effect of genotype and year on six leafy and non-leafy silage maize hybrids over a period of four years (2002–2005), with special emphasis on the plant height, ear attachment height, leaf number, and fresh and dry matter yield.The results showed that the number of leaves above the ear was much higher for the two leafy hybrids (8.00 and 9.35) than the average of the other hybrids (5.56, averaged over the years). This trait was in close negative correlation (r
= −0.7346) with the ratio of ear attachment height to total plant height, a trait with strong genetic determination, little influenced by the year. In leafy hybrids the main ear was located far lower down, but the total plant height was similar to that of the other hybrids. The ratio of ear attachment height to plant height was 0.36 for the leafy hybrids, but ranged from 0.41 to 0.45 for the other hybrids (averaged over the years). In wetter years the hybrids were taller and had greater dry matter production per plant than in the dry year.
Authors:Z. Gyenes-Hegyi, I. Pók, L. Kizmus, and et al.
The plant height and the height of the main ear were studied over two years in twelve single cross maize hybrids sown at three different plant densities (45, 65 and 85 thousand plants/ha) at five locations in Hungary (Keszthely, Gönc, Gyöngyös, Sopronhorpács, Martonvásár). The results revealed that plant height and the height of the main ear are important variety traits and are in close correlation with each other. It was found that the hybrids grew the tallest when the genetic distance between the parental components was greatest (Mv 4, Mv 5). The height of the main ear was also the greatest in these hybrids, and the degree of heterosis was highest (193% for plant height, 194% for the height of the main ear). The shortest hybrids were those developed between related lines (Mv 7, Mv 11). In this case the heterosis effect was the lowest for both plant height (128%) and the height of the main ear (144%). The ratio of the height of the main ear to the plant height was stable, showing little variation between the hybrids (37–44%). As maize is of tropical origin it grows best in a humid, warm, sunny climate. Among the locations tested, the Keszthely site gave the best approximation to these conditions, and it was here that the maize grew tallest. The dry, warm weather in Gyöngyös stunted the development of the plants, which were the shortest at this location. Plant density had an influence on the plant size. The plants were shortest when sown at a plant density of 45,000 plants/ha, and the main ears were situated the lowest in this case. At all the locations the plant and main ear height rose when the plant density was increased to 65,000 plants/ha. At two sites (Gönc and Sopronhorpács) the plants attained their maximum height at the greatest plant density (85,000 plants/ha). In Keszthely there was no significant difference between these two characters at plant densities of 65 and 85 thousand plants/ha, while in Gyöngyös and Martonvásár the greatest plant density led to a decrease in the plant and main ear height. The year had a considerable effect on the characters tested.
Authors:E. Nagy, I. Timár, Z. Hegyi, T. Spitkó, and L. Marton
The chemical composition of maize makes it suitable for a wide range of nonconventional uses, including utilisation as a new source of energy for the 21st century as a raw material for biofuel. The aim of the experiments was to amalgamate the application of genetic markers with conventional breeding methods to produce maize hybrids whose starch content and ecostability satisfied the demands of industrial use, while having yield potential and agronomic traits on a par with those of hybrids currently cultivated. The chemical quality of 220 lines was evaluated using the NIR spectrometric technique, and the five maize inbred lines with the lowest and highest starch contents were selected for genetic marker studies. The variety identification of the lines was carried out using the isoenzymes stipulated by UPOV. The following SSR (simple sequences repeat) markers were tested: phi 095, umc 1057, nc 004, phi 096, nc 007, umc 1564, phi 85, y1 SSR, umc 1178, nc 009, phi 070, umc 1066, umc 1741, umc 1069, phi 033, phi 061, wx, phi 032, phi 084 and phi 062. The analysis of the fragment patterns revealed three SSR markers that appeared to be correlated with the starch content of the maize lines. These were the primer pairs
y1 SSR, umc 1069
. These results are only of a preliminary nature, however, as the incorporation of starch is probably regulated by several genes, and the studies suggest it is also influenced by several environmental factors. It also appears likely that the bioethanol yield is determined not only by the starch content, but also by other parameters. Further research should thus be expanded to include investigations into the structural and fermentability traits of starch molecules, including the characterisation of these traits using genetic markers.
Authors:T. Berzy, T. Janda, Z. Hegyi, and J. Pintér
The research, carried out in the Martonvásár phytotron in 2007, was aimed at determining how the leaf water potential of maize hybrids produced in direct and reciprocal crosses, and thus possessing different levels of seed vigour, changed as the result of water withholding in the flowering phenophase. In the case of the silage maize hybrids Mv 290 and Lima it was found that seedling vigour influenced the plant height (measured at 30 days) of adult plants. Crosses produced on chilling-sensitive female genotypes (GL, AM, H29), such as the hybrids Káma, Maraton and Hunor, proved to be unambiguously stress-sensitive if water was withheld for more than six days. In all cases drought stress reduced the relative quantum efficiency, irrespective of the crossing combination.
An experiment was set up at five locations in Hungary in 2005, in a randomised block design with four replications. At each location 24 hybrids were tested from each of four maturity groups (FAO 200, FAO 300, FAO 400, FAO 500). Evaluations were made of the yield average (t/ha) and the yield components of the sample ears: ear length, number of kernel rows, thousand-kernel mass and kernel/cob ratio. This was followed by chemical analysis to determine the protein, oil and starch contents of the kernels. The chemical quality parameters were recorded for almost 100 hybrids, and the correlations of the protein, oil and starch contents with yield and yield components were analysed. It was found that in all the maturity groups the yield was closely correlated with the thousand-kernel mass (0.72). In each maturity group the highest yield averages were associated with the greatest average starch contents, except for the FAO 500 group in the Szarvas location, where the development of secondary ears contributed to the achievement of the highest yield average. A very close correlation was found between the starch content and the thousand kernel mass (0.91). The variety caused greater differences in protein content than the location. This was also true for the oil content in the FAO 200 and FAO 400 groups, but only in the FAO 400 group in the case of starch content. More starch was incorporated at wetter locations, where the protein content of the samples was lower.
Authors:Z. Hegyi, I. Pók, T. Berzy, J. Pintér, and L. Marton
A total of 96 hybrids from four maturity groups (FAO 200, 300, 400, 500) were tested in two years (2006, 2007) at two locations in Hungary (Martonvásár, Szarvas). Considerable differences were found between the years for the grain yield per hectare and for the grain quality parameters. In 2006 record yields were achieved at both locations, averaging 11.61 t/ha in Martonvásár and 12.20 t/ha in Szarvas, due primarily to well-timed irrigation in Martonvásár and to good rainfall supplies in Szarvas. In 2007 both locations suffered from drought, with less rainfall than average during the critical months of the vegetation period, which was partially compensated for by irrigation in Martonvásár, giving a yield average of 5.96 t/ha, while the hybrids grown in Szarvas had a yield average of 5.06 t/ha. The grain quality parameters exhibited a close correlation with the grain yield in the individual FAO maturity groups. Hybrids of the flint type, which have a short vegetation period, had high protein and oil contents, but the yield averages were low due to the slower rate of starch incorporation. Hybrids of the dent type have a longer vegetation period and more intense carbohydrate accumulation, but low protein and oil contents. In wet years and locations there was a higher rate of starch accumulation, while dry years are favourable for protein and oil accumulation. The Bravais correlation coefficient was calculated between the yield and the grain quality parameters (averaged over years, locations and varieties). A positive, moderately strong correlation (0.68) was found between the yield and the starch content, a negative, moderately strong correlation (−0.52) between the yield and the protein content, and a loose negative correlation (−0.19) between the yield and the oil content.