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Microbiology and International Conference on Applied Biology and Biotechnology. August 1988, Hong Kong, pp. 565-569. Tsang, L.J., Reid, I.D. & Coxworth, E.C. (1987): Delignification of wheat straw by Pleurotus spp. under

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Mészlepedékes csernozjom vályogtalajon, az MTA ATK TAKI Nagyhörcsöki Kísérleti Telepén (Mezoföldön) vizsgáltuk a K, B és Sr elemek közötti kölcsönhatásokat oszi búzában. Az alaptrágyázás általában 100–100 kg N és P2O5·ha−1·év−1 volt, amelyet 25%-os pétisó és szuperfoszfát formájában adtunk ki. A K-szinteket megismételt 0, 1000, 2000 kg K2O-, a B-szinteket megismételt 0, 20, 40, 60 kg B-, a Sr-szinteket 67 kg Sr hektáronkénti adaggal állítottuk be. Mutrágyaként 60%-os KCl-ot, 11%-os bóraxot és 33%-os SrCl2·6H2O sót alkalmaztunk. Foparcellánként 3 K-kezelés, alparcellánként 4 B-kezelés, al-alparcellánként 2 Sr-kezelés szolgált, 24 kezeléssel×3 ismétlésben = 72 parcellával, osztott parcellás elrendezésben.A kísérlet beállításakor (1987 oszén) a szántott réteg 5% CaCO3-ot, 3% humuszt, 20% agyagot tartalmazott. A pH(H2O) 7,8; a pH(KCl) 7,3; az AL-oldható K2O és P2O5 180–200 és 100–120, a KCl-oldható Mg 110–150, a KCl+EDTA-oldható Mn 60–80, a Cu és Zn 1–2, valamint a B 0,7 mg·kg−1 értékkel volt jellemezheto. A termohely kielégíto K-, Ca- és Mg-; közepes N- és P-; valamint gyenge Zn- és Cu-ellátottságú. A talajvíz szintje 13–15 m mélyen található, a terület aszályérzékeny. Az átlagos középhomérséklet 11°C, az éves csapadékösszeg 400–600 mm közötti, egyenetlen eloszlással.A fobb megállapítások, levonható tanulságok:

  1. Ezen a káliummal és bórral egyaránt kielégítoen ellátott mészlepedékes csernozjom vályogtalajon trágyahatások a termésben nem jelentkeztek. Az elovetemény cirok kiszárította a talajt, a búza 9 hónapos tenyészideje alatt mindössze 234 mm csapadékot kapott. Ebben a száraz évben 3,0 t·ha-1 szalma- és 3,5 t·ha−1 szemtömeg képzodött átlagosan.
  2. A szalma és szem B-tartalmát a B- és K-trágyázás egyaránt közel a kétszeresére emelte, így a kontrollon mért B-tartalmak átlagosan a négyszeresére nottek. A Ktrágyázás ezen túlmenoen nagyobb K-, illetve mérsékeltebb Mg-tartalmakat eredményezett a szalmában. A Sr-trágyázással enyhén nott a szalma Sr-, illetve mérséklodött Na-tartalma.
  3. A kicsi szalmatermés és az extrém nagy K-kínálat nyomán a szalma 4,22% K-tartalmat halmozott fel. Az 1 t szemtermés és a hozzátartozó melléktermés ún. fajlagos/egységnyi K-tartalma és Mg-tartalma több mint kétszeresen haladta meg a szokásosat, ezért félrevezeto lehet a szaktanácsadás számára.
  4. A felvett K 90%-át, illetve a Sr 98%-át a melléktermés szalma halmozta fel.

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Both deficiency and excess of P, Zn and Cu are common in soils and crops of Hungary. The excess and deficiency of P occurring in agricultural soils and crops is a consequence of previous fertilization practice. Zn deficiency occurs mainly on calcareous soils well fertilized with P under maize, while Cu deficiency is often detected on poor sandy soils and on organic soils under other crops. Zn and Cu excess has been measured in city soils, in soils near highways and industrial areas.  In the present paper the effect of P supply is shown on yield and P/Zn ratios of crops, presenting the phenomena of the P-induced Zn deficiency on a calcareous loamy chernozem soil. In an other long-term field trial on the same soil, the effect of Cu and Zn loads was studied on soil and crop. The main conclusions drawn from these long-term field experiments are as follows: 1. An excess of available P in the plough layer of this soil might be detected by the ammonium lactate (AL) method when the soil analysis shows concentrations higher than 150-200 mg/kg P 2 O 5 . The P/Zn ratios of 6-leaf stage shoots and harvested straw of maize grown on these plots might be higher than 200, while that of grain 150-200. 2. In the frame of a fertilization program, P-induced Zn deficiency can be counterbalanced effectively on such calcareous chernozem soils with the application of P and Zn fertilizers in a ratio around 10:1. 3. The Cu content of crops could not be markedly raised by using CuSO 4 fertilizer, even with rates as high as 270 or 810 kg/ha Cu. However, as an effect of increased NxP fertilization, the Cu content of maize grain doubled, or that of maize straw was 4-times higher. This is an important tool for the Cu enrichment of animal diet, when maize straw is also used for animal feeding. 4. The soil and plant analysis data are proper means of controlling soil fertility and crop nutritional status when the soil and plant data are previously calibrated in long-term field experiments.

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Field experiments with 12 winter wheat cultivars differing in N grain concentration were carried out during the vegetative years 2004/05 and 2005/06 using three variants of N fertilization (N1 = 0 kg N ha−1, N2 = 100 kg N ha−1, N3 = 200 kg N ha−1). The aim was to determine the effect of cultivar, N fertilization and weather conditions of the respective years on the relative N translocation and grain quality. Biomass N concentration at the stages of heading (Nbh) and maturity (Nbm), grain N concentration (Ng) and straw N concentration (Nv) were determined. The decrease of N concentration in vegetative biomass during grain filling Nv / Nbh was denoted as a relative N translocation — RNT and ratio Ng / Nv as a relative N accumulation — RNA. Low differences in Nbh and Nbm were observed between years and significant difference in Ng and Nv was due to different RNT and RNA efficiency. In the year with low RNT efficiency, Nv was high and Ng and RNA low. N fertilization increased biomass N concentration, more in the vegetative organs than generative ones. Higher N rates decreased efficiency of fertilization which was expressed in RNT and RNA decrease. In the year with low RNT efficiency, the decrease of fertilizer efficiency had a multiplier effect. Cultivars have differed in Nv, Ng, RNT and RNA but their response to N fertilization was similar. Only some cultivars (Zlatka, Renan and Tamaro) possessed N grain concentration answering food end-use without N fertilization but only in the year favourable for N translocation. Certain cultivars (Sonata and Malyska) did not have food quality at all, not even at rate 200 kg N ha−1. Straw N concentration depended strongly on the cultivar efficiency of decreasing N concentration in vegetative biomass during grain filling (RNT). On the contrary, a negative relationship was observed between straw N concentration and Nbh. Cultivars with high RNT efficiency had low Nv, high Ng and high RNA. Possibilities of utilization RNT and RNA as selection criterions on high Ng were recommended.

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-Methangärung organischer Abfallstoffe 1982 Llabrés-Luengo P., Mata-Alvarez J.: Influence of temperature, buffer, composition and straw

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The results of a field study revealed that the application of fertilizers to the companion crop in a millet/legume intercropping system is essential to optimize the yield of the legume component. Supplying nutrients to the main crop alone tended to decrease the productivity of the companion crop, probably because of shading as a result of overgrowth of the main crop. The highest contents of N and P in the grain and straw of the intercrop were recorded with 100% of the recommended dose to both the component crops (M100I100). However, the uptake of nutrients was highest from the plots receiving 50 and 100% of the recommended dose to the main and companion crop, respectively (M50I100). Higher uptake was due to the fact that the yields increased to a greater extent than the nutrient concentrations.

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Experiments involving the intercropping faba bean with each of lupin, fenugreek and Egyptian clover as well as growing faba bean alone were carried out at Assiut University on a farm naturally infested with Orobanche in two seasons. The major objective of the study was to investigate the effect of different intercropping combinations with faba bean on the infestation with Orobanche. The results obtained revealed that intercropping faba bean with each of lupin, fenugreek and Egyptian clover markedly reduced the Orobanche crenata Forsk infestation of faba bean. the number of branches, the height of the first pod, the number of pods, the seed yield and the number and dry weight of Orobanche spikes were significantly affected by the intercropping treatments, but these had no significant influence on plant height, straw yield or 100-seed weight. intercropping faba bean with each of lupin, fenugreek and Egyptian clover increased the faba bean seed yield, consequently the economic return was also increased.

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Durum wheat landraces are still cultivated to take advantage of their excellent grain and straw quality, adaptation to abiotic stresses, and extremely wide variety of uses. The safeguarding and rehabilitation of genetic inheritance requires genetic characterization and evaluation. In this study, forty durum wheat landraces originating from Mediterranean countries were evaluated according to agro-morphological and technological properties. We show that the germplasm was highly variable. The mean yellow pigment and protein content was higher in landraces (15.58%; 7.32 ppm) than in the Moroccan cultivars used as controls (14.6%; 5.48 ppm). In addition, principal component analysis identified five groups showing variable agronomic and qualitative characteristics that might be useful in the rational design of breeding programs.

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The first grown deep-rooting crop, maize in 1991 and sunflower in 1998 did not reveal any yield loss on the contaminated soil. The crops responding most sensitively to As were peas, winter wheat and winter barley. In the 4 th year of the trial the peas practically died out on the highest As level.  The “total” As (digested with cc. HNO 3 + cc. H 2 O 2 ) amounted to 70-80% of the As added to the ploughed layer 4 years earlier. The NH 4 -acetate + EDTA soluble As fractions revealed great fluctuations during the sampling time. In the first 4 years the ratio of As detectable in the ploughed layer in this form ranged between 12 and 30%, while in 2000 between 10 and 13%. On the basis of deep profile sampling, it was established that As displayed no significant vertical movement after 10 years, using the HN 4 -acetate + EDTA method (Lakenen & Erviö, 1974). The concentration of As, as a rule of thumb, declined in the direction from root-shoot-leaves-straw-grain in grain crops. The mobility of As is limited within the soil-plant system at this site. Even on the heavily loaded soil, the amount of As in the whole above-ground biomass remained negligible, usually below 5-10 mg As/kg dry matter. Under such conditions, the remediation of soil contaminated with higher loads would theoretically take thousands of years in the case of As via plant uptake. The transfer coefficient, expressing the total straw/soil As concentration by barley, had a value of 0.02. As does not seem to be a very dangerous contaminant either to soil, plants or groundwater. Extreme loads, however, caused phytotoxicity in some crops and resulted in products unfit for animal or human consumption. Soil life was also damaged. Higher As loads decreased nodule formation by green peas, and the endomycorrhizal symbiosis was hindered as well. 

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Field experiments were conducted for two crop years at the Indian Agricultural Research Institute, New Delhi to study the effect of enriching wheat residue with legume residue on the productivity and nitrogen uptake of a rice-wheat cropping system and soil fertility. The incorporation of wheat residue had an adverse effect on the productivity of the rice-wheat cropping system. When it was incorporated along with Sesbania green manure, not only did its adverse effect disappear but the response to fertilizer N was also increased. There was no response to fertilizer N when Sesbania green manure was incorporated. When wheat residue was incorporated along with Sesbania green manuring, rice responded significantly to fertilizer N up to 120 kg N ha-1 in the first year and to 60 kgN ha-1 in the second year and at these levels of N, Sesbania + wheat residue gave 0.8 to 1.2 t ha-1 more grain, 0.6-1.0 t ha-1 more straw and 8-15 kg ha-1 more N uptake of rice resulting in 0.04-0.17% more organic C, 3-8 kg ha-1 more available P and 17-25 kg ha-1 more available K content in the soil than wheat residue alone at the same rates of N application. The respective increaseas caused by Sesbania green manure + wheat residue over Sesbania green manure alone were 0.3-0.5 t ha-1 in the grain and straw yield, 1-9 kg ha-1 in the N uptake of rice, 0.02-0.10% in organic C, 1-8 kg ha-1 in available P and 35- 70 kg ha-1 in available K content in the soil. These treatments also gave higher residual effects in succeeding wheat than wheat residue alone. The incorporation of residues of both wheat and Sesbania is thus recommended to eliminate the adverse effect of wheat residue and to increase the beneficial effects of Sesbania green manuring.

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