kukorica hibridek (
L.) szemtermésére és N-műtrágyareakciójára tartamkísérletekben az 1970–1991. Években. (Effect of N-fertilization and year on the grain-yield and N-fertilizer-reaction in maize hybrids (
L.) in long-term trial in
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.
As many have noted, the journal impact factor (JIF) may be the most widely used scientometric indicator. This indicator is computed for each year (Y) according to the following equation (Glänzel and Moed 2002
The yield, protein and starch content of Martonvásár maize hybrids belonging to different FAO groups were examined in experiments involving early, optimal and late sowing dates in two different years (drought — 2007, favourable water supplies — 2008) on a calcareous chernozem soil with loam texture at the Látókép Experimental Station of the Centre of Agricultural Sciences and Engineering, University of Debrecen.Sowing date had a significant effect on maize grain yield in the dry year. The grain yields of hybrids with longer growing periods were significantly higher than those with shorter growing periods in both years, but they reacted sensitively to the change in sowing date in the dry year. Due to the rainfall distribution in the growing season, sowing date did not modify the performance of the hybrids in the year with favourable water supplies. Sowing date had a significant effect on the grain protein content in the dry year, with significantly higher values after late sowing than after early or optimal sowing. Averaged over the sowing dates, the protein content of the FAO 200 hybrid was significantly higher in both years than that of hybrids in other FAO groups. In the dry year, the greatest difference in protein content could be observed between the early and late sowing dates for hybrids in all four FAO groups. A negative correlation was found between yield and protein content. Sowing date significantly increased the starch content of maize in the favourable year, with a significant difference between early and late sowing dates.In the dry year higher starch contents were recorded for all the hybrids and for all the sowing dates than in the favourable year. In the dry year, sowing date only caused a significant difference in the starch content in the case of FAO 200 sown at optimal and late sowing dates. In the favourable year, a significant difference was only obtained for the starch content of the FAO 400 hybrid sown at early and late sowing dates. Satisfactory quality can only be achieved if suitable genotypes are grown with appropriate technologies.
Cooper, Z., Doll, H. A., Hawker, D. M., et al.: Testing a new cognitive behavioural treatment for obesity: a randomized controlled trial with three-year follow-up. Behav. Res. Ther., 2010, 48 (8), 706–713.
Short-term fluctuations of indoor radon may occur due to weather conditions, seismic activity etc. These average out during the year. According to our measurements, in the very same room the yearly average of radon concentration may also change by 25–50% from year to year. This observation may make the comparison of indoor radon levels of houses measured in different years unjustified; large scale radon maps based upon such data are less reliable. Possible causes of such year-by-year changes are discussed empirically. The conclusions may be helpful to foresee long-term tendencies, implied by changes of living habits and by climatic shifts.
.: Prospective randomized trial comparing endovenous laser ablation and surgery for treatment of primary great saphenous varicose veins with a 2-year follow-up. J. Vasc. Surg., 2010, 52 , 1234–1241.
Gyenesné Hegyi, Z., Pók, I., Illés, O., Szőke, C., Kizmus, L., Marton, L. C. (2002): A termőhely, a tőám és az évjárat hatása kukoricahibridek terméselemeire. (Effect of growing site, plant density and year on the yield components of maize hybrids