Sándor Hoffmann

Effect of mineral and organic fertilization on crop yield, nitrogen uptake, carbon and nitrogen balances, as well as soil organic carbon content and dynamics: results from 20 European long-term field experiments of the twenty-first century

Assembled results from 20 European long-term experiments (LTE), mainly from the first decade of the twenty-first century, are presented. The included LTEs from 17 sites are the responsibility of institutional members of the International Working Group of Long-term Experiments in the IUSS. Between the sites, average annual temperatures differ between 8.1 and 15.3°C, annual precipitation between 450 and 1400 mm, and soil clay contents between 3 and 31%. On average of 350 yield comparisons, combined mineral and organic fertilization resulted in a 6% yield benefit compared with mineral fertilization alone; in the case of winter wheat, the smallest effect was 3%, the largest effect, seen with potatoes, was 9%. All unfertilized treatments are depleted in soil organic carbon (SOC), varying between 0.36 and 2.06% SOC. The differences in SOC in unfertilized plots compared with the respective plots with combined mineral (NPK) and organic (10 t ha−1 farmyard manure) fertilization range between 0.11 and 0.72%, with an average of 0.3% (corresponding to ∼15 t ha−1). Consequently, the use of arable soils for carbon sequestration is limited and of low relevance and merely depleted soils can temporarily accumulate carbon up to their optimum C content.

Influence of mineral and organic fertilizers on soil organic carbon pools

Abstract The influence of farmyard manure (FYM) and equivalent mineral NPK application on organic matter content, hot water extractable carbon (HWC), microbial biomass C (Cmic), and grain yields in a long-term field experiment was assessed after 40 years in Hungary. The unfertilized plot, FYM fertilized plots and plots fertilized with equivalent NPK fertilizer contained 0.99%, 1.13% and 1.05% total organic carbon (TOC) respectively. Compared to the unfertilized plot, FYM application resulted in 8.2% higher TOC than equivalent NPK fertilization. The highest TOC was only 1.21%, much lower than expected for a soil containing 21.3% of clay. The quantity of HWC varied depending on the type of fertilization: Compared to control, FYM treatments lead to 29% more HWC than mineral fertilization (FYM: 328 mg kg−1; NPK: 264 mg kg−1). The impact of FYM and equivalent NPK fertilizer on Cmic was contrary. FYM and NPK resulted in 304 and 423 mg kg−1 Cmic, respectively. The difference was 119 mg kg−1; 42% as compared to the unfertilized plot. Despite the higher HWC content, FYM treatments lead to significantly less (35%) grain yields than equivalent NPK doses; Cmic content showed closer correlation to grain yields.

Humus und Klimaänderung - Ergebnisse aus 15 langjährigen Dauerfeldversuchen

Zusammenfassung Die Quantifizierung des Einflusses von Klimaänderungen auf den Humusgehalt des Bodens ist von großer wirtschaftlicher und wissenschaftlicher Bedeutung. Eine Möglichkeit dieser Quantifizierung besteht in der Auswertung von Dauerfeldversuchen mit der kontinuierlichen Bestimmung des Kohlenstoff- und Stickstoffgehaltes von Böden über einen Zeitraum von mehreren Jahrzehnten unter Wahrung des Ceteris-Paribus-Prinzips. Für die vorliegende Arbeit wurden die Ergebnisse von insgesamt 15 Dauerfeldversuchen an zehn verschiedenen Standorten mit rund 150 unterschiedlichen Düngungsvarianten ausgewertet. Die Versuchsdauer lag mit einer Ausnahme zwischen 40 und 110 Jahren. Die Corg-Daten konnten nahezu lückenlos über einen Zeitraum von jeweils 20 Jahren einbezogen werden. Die Nt-Gehalte wurden in sechs Versuchen berücksichtigt. Die Ergebnisse zeigen, dass bei allen Prüfgliedern mit kombinierter organisch-mineralischer Düngung in der Größenordnung, wie sie der “guten fachlichen Praxis“ oder auch der Humusbilanzmethode entspricht, keine Verringerung der Corg-Gehalte eingetreten ist. In einigen Fällen waren signifikante Erhöhungen zu verzeichnen. In 11 von 15 Versuchen war auch ohne Düngung oder mit ausschließlicher Mineraldüngung keine Reduzierung und somit keine klimabedingte Verringerung der Humusgehalte im Untersuchungszeitraum nachweisbar. Stattdessen wurde in einigen Fällen eine signifikante Erhöhung gefunden. Auch bei den Nt-Gehalten war in keinem Fall eine signifikante Verringerung festzustellen. Umfangreiche Großzahlanalysen und Dauerfeldversuchsauswertungen anderer Autoren bestätigen uneingeschränkt die Ergebnisse.

Grain yield and baking quality of wheat as affected by cropyear and plant nutrition

Hungarian agriculture is traditionally connected with the growing of winter wheat, which emerges from his suitable climatic characteristics. Despite of the general favourable meteorological situation, individual crop years can cause very different climatic conditions and also the territory of our land consists of more and less favourable wheat growing sites. Among climatic impacts especially weather conditions before harvesting influence baking quality (Tandcs et al. 2005). Heat stress can damage flour quality as well (Bencze et al. 2004). Effects of less favourable climatic and site conditions can be reduced by proper agronomy and growing excellent genotypes (Szentpeteri et al. 2004a, 2004b). Long-term field experiments have a very important role for assessment of agronomic impacts, because their history is well known and documented.

Der internationale organische stickstoffdauerdüngungsversuch (IOSDV) keszthely nach 12 versuchsjahren

Der Internationale Organische Stickstoffdauerdungungsversuch wurde 1984 in Keszthely auf einer Braunerde mit 3 Stufen organischer Dungung und 5 Stufen mineralischer N‐Dungung in einer Fruchtfolge mit Mais — Winterweizen ‐ Wintergerste angelegt. Die Kornertrage im Zeitraum 1984–1995 (vier Rotationen) werden mitgeteilt. Die positive Wirkung bzw. Nachwirkung von Stallmist zeigte sich mit abnehmendem Bedarf an mineralischer N‐Dungung bei Mais und Wintergerste und mit hoherem Maximalertrag bei Winterweizen. Die Strohdungung wirkte schwacher und ergab niedrigere Ertrage bei Mais und Wintergerste als die mineralische N‐Dungung allein. Mit fortschreitender Versuchsdauer hat die Fruchtbarkeit des Bodens der organisch und mineralisch gedungten Parzellen zugenommen und wahrend dieser Zeit ist auch die Produktivitat der Nullparzellen nicht gesunken.

Soil fertility as affected by long-term fertilization and crop sequence

In a crop rotation with potato, maize and winter wheat, increasing doses of farmyard manure (FYM) or equivalent NPK fertilizers and their combinations were analyzed with special regard to their long-term influence on soil fertility. The yield-increasing capacity of FYM doses was only 82%, as compared to the equivalent amount of mineral NPK. On the unfertilized plots, fairly high N-release (50.9 kg ha−1) could be observed. Great differences in N-utilization developed depending on the form and dose of fertilizers. N-utilization from FYM was only 29.3%, while that of equivalent fertilizer application was 49.8%. The lowest soil reactions were observed both without fertilization and with the highest NPK doses. Negative N-balances generally resulted in low soil organic matter content. While FYM and equivalent NPK fertilizers similarly influenced the ammonium lactate-extractable AL-K2O content of the soil, an increased AL-P2O5 content could be observed in the case of mineral fertilization. The worst previous crop of wheat was maize (100%), wheat itself was better (133%), and potato was markedly good. The worst previous crop of maize was itself (100%), while wheat and potato were equally favorable (136–137%).

Einfluss langjähriger organischer und mineralischer N‐düngung auf gehalt an Corg und N‐verlagerung

Der Gehalt an Corg verandert sich signifikant durch die Stallmist‐ und Strohdungung, aber die mineralische N‐Dungung allein hat keine Veranderung verursacht. Hohe Eintrage durch die hochsten N‐Stufen mit Strohdungung haben Nitratanreicherung und eine Abwartsbewegung der NO3‐K.onzentrationsspitze bewirkt, die vermutlich zu einer Belastung des Grundwassers fuhren wird. Die Ergebnisse zeigen, das bei einer N‐Gabe uber ca. 150 kg/ha eine weitere N‐Ausgleichdungung fur Strohabbau uberflussig ist, sie kann zur Auswaschung fuhren. Der Stalldung hat, auch bei hoheren N‐Stufen, keine ausgepragte Nitratkonzentration im Unterboden verursacht. Der Ammonium N‐Gehalt im Bodenprofil zeigt keine wesentlichen Differenzen in Abhangigkeit von organischer und mineralischer Dungung. Die Menge Ammonium‐N ist aber bedeutend und macht etwa die Halfte des Nitrat‐N aus, ist jedoch nicht konstant.

Impact of mineral and organic fertilization on yield, C content in the soil, as well as on C, N and energy balances in a long-term field experiment

Data from a 49-year-long organic–mineral fertilization field experiment with a potato–maize–maize–wheat–wheat crop rotation were used to analyse the impact of different fertilizer variations on yield ability, soil organic carbon content (SOC), N and C balances, as well as on some characteristic energy balance parameters. Among the treatments, the fertilization variant with 87 kg ha−1 year−1 N proved to be economically optimal (94% of the maximum). Approximately 40 years after initiation of the experiment, supposed steady-state SOC content has been reached, with a value of 0.81% in the upper soil layer of the unfertilized control plot. Farmyard manure (FYM) treatments resulted in 10% higher SOC content compared with equivalent NPK fertilizer doses. The best C balances were obtained with exclusive mineral fertilization variants (−3.8 and −3.7 t ha−1 year−1, respectively). N uptake in the unfertilized control plot suggested an airborne N input of 48 kg ha−1 year−1. The optimum fertilizer variant (70 t ha−1 FYM-equivalent NPK) proved favourable with a view to energy. The energy gain by exclusive FYM treatments was lower than with sole NPK fertilization. Best energy intensity values were obtained with lower mineral fertilization and FYM variants. The order of energy conversion according to the different crops was maize, wheat and potato.

Cianobaktériumok és eukarióta algák talajszuszpenzióból történő közvetlen vizsgálatának lehetősége áramlási citométerrel

A talajokban elő cianobakteriumok es eukariota algak edafonban betoltott szerepe kulcsfontossagu. Eddig megismert kolcsonhatasaik a talaj mas szervezeteivel es a magasabb rendű novenyekkel, valamint hozzajarulasuk a talajok mikroszerkezetenek kialakulasahoz es a nitrogenellatashoz a legismertebbek. A talajalgak mennyisegi es minősegi kimutatasara meglehetősen keves kozvetlen es kozvetett sejtszamolasi modszer es adat all rendelkezesre. Jelen munkankban Ramannfele barna erdőtalajon őszi buza, biborhere, kukori-ca es szoja parcellakbol gyűjtott talajmintak cianobakterium es eukariota mikroalga sejtszam vizsgalatat vegeztuk el egy — ezen a teren meg ujnak szamito — nagysebes-segű, automatizalt sejtanalitikai modszer, az aramlasi citometria alkalmazasaval. A negy novenykulturabol 2013 juliusaban, Keszthelyen, a felszini ot centimete-res talajretegből hat ismetlesben vett talajmintakbol vizes szuszpenziot keszitettunk, majd mertuk azok aktiv algasejt-tartalmat. A cianobakteriumokat es az eukariota algakat klor...

Adaptability of winter wheat genotypes originating from composite crosses to organic and low input conditions

One of the biggest challenges for the safe maize production is the yield stability in a wide range of environments with different soil fertility, weather conditions, prevailing pests and diseases as well as cultural practices. In order to achieve it, new hybrids with higher tolerance to biotic and abiotic stress are continuously being created. In order to compare performance of maize hybrids in environments with different levels and types of stress, and relate it to the stalk lodging incidence, we compared performance of 64 maize hybrids obtained by crossing 16 inbred lines with four inbred testers in three different environments. Two environments at same location (Rugvica) differed in crop rotation, and the third environment at location Botinec was considered as dry because of low water capacity of the soil. Mixed models that included all design elements and genetic background of hybrids were used to analyze the effect of lodging on yield in different environments. The results show that stalk lodging had a significant effect on yield, but significant lodging x environment interaction indicates that this effect was rather environment specific.Sweet pepper Istra F1 hybrid was grown in a greenhouse on K rich soil. For evaluation of K antagonism, two K rates (55 and 85 kg ha-1) were applied in a randomized complete block design with four replications. Total number of fruits, total number of BER affected fruits as well as average fruit mass were recorded for each harvest. Fruit and leaf K and Ca content were determined at three plant growth stages (at the stage of the first, third and fifth fruit cluster). Higher K rate gave higher : average fruit mass (169.45 g), total number of fruits per plant (7.95), number of BER affected fruits per plant (3.82), K in leaves (5.44% DM), K in fruits (6.35% DM), but negatively correlated with Ca concentration in fruits (0.57% DM) and leaves (3.24% DM). This resulted in decreased marketable yield of sweet pepper fruits.