摘要:

Iron‐Chlorosis is a world‐wide problem, particularly in semi‐arid regions containing calcareous soils. Although most soils contain adequate total iron, the amount available to the plant is dependent on factors such as iron species and plant genotype.

ISSN:0190-4167    

DOI:10.1080/01904168409363172

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904168409363171

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Many different kinds of soil additives have been studied with the aim of preventing and/or correcting iron deficiencies of plants. Application rates have varied from as little as “parts per million”; of several Fe chelates, to as much as many tons per hectare of acidifying soil amendments, or organic materials such as manures, sewage sludges and plant residues. The chelate Fe EDDHA has generally been considered to be the most effective soil applied material in alleviating chlorosis: its use is somewhat limited, however, by its relatively high cost. Broadcast applications of acidifying materials such as elemental sulfur and sulfuric acid must generally be excessively high to be effective. Recent studies involving band placements of these acidifying materials have shown some promise. Several industrial by‐products have also proven effective, especially when concentrated in bands close to germinating seeds.

ISSN:0190-4167    

DOI:10.1080/01904168409363173

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Fe chlorosis occurs in many plant species although chlorosis of monocots and dicots generally occurs under different soil and climatic conditions. Because an understanding of causal factors for chlorosis is important in diagnosis, the factors which promote iron chlorosis and the regulation of Fe uptake potential are reviewed.

ISSN:0190-4167    

DOI:10.1080/01904168409363174

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Although the total Fe‐concent is sometimes a misleading index of the Fe‐status of crops, it would be nevertheless a desirable one, since it is obtained anyhow in the usual plant analysis. It can be shown for cereals and oilseed rape that the total Fe‐content provides an equivalent good information compared with several extractions of ‘active’ Fe, provided that the plants are carefully cleaned from dust. However, the ‘active’ Fe (obtained with chelates or weak organic acids) has the advantage that even samples of a doubtful degree of cleanliness can be evaluated.

ISSN:0190-4167    

DOI:10.1080/01904168409363175

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904168409363176

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Experiments were conducted to test the ability of ferrous iron (Fe2+) chelating agents to discriminate between Fe2+and ferric iron (Fe3+), to determine ranges of Fe2+detection in reactions, to determine interactions of chelating agents with phosphorus (P) which is common in plant tissue, and to evaluate some of the complexities of methodology for Fe2+determinations. PDTS [ferrozine; 3‐(2 pyridyl)‐5,6‐bis (4‐phenyl‐sulfonic acid)‐l,2,4‐triazine] reacted with only small amounts of Fe3+, had a fairly wide range of Fe2+detection (0–200 μg), P did not interfere with the reaction, and methodology was relatively simple. TPTZ [2,4,6‐tripyridyl‐s‐triazine] was very specific for Fe2+, did not react with Fe3+, had a relatively narrow range of Fe2+detection (0–40 μg), P did not interfere with the reaction, and methodology was relatively simple. BPDS [4,7‐diphenyl 1.10‐phenanthrolinedisulfonic acid] reacted with a small amount of Fe3+, had a fairly wide range of Fe2+detection (40–200 μg), did not react with low levels of Fe2+(<40 μg), P did not interfere with the reaction, and the methodology was relatively simple. OPh [1,10‐o‐phenanthroline] reacted extensively with Fe3+, had a wide range of Fe2+detection (0–200 μg), P did not interfere with the reaction, and methodology was relatively simple. BDTPS [2,4‐bis(5,6‐diphenyl‐1,2,4‐triazine‐3‐yl)‐pyridinetetrasulfonic acid], BPT [4,7‐diphenyl‐1,10‐phenanthroline], and PDT [3‐(2pyridyl)‐5,6‐diphenly‐1,2,4‐triazine] were considered, but the literature indicated that P interferred with BDTPS and BPT reactions, citrate interferred with the BPT reactions, and the methodologies for PDT and BPT were relatively complex (required special separations and extractions). PDTS was the best of the chelating agents tested for Fe2+determinations. OPh plus hydroxylamine (OPhH) was the best of the chelating agents for the determination of total Fe.

ISSN:0190-4167    

DOI:10.1080/01904168409363177

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Experiments were conducted to determine ferrous iron (iron2+, Fe2+) in plant tissues. Iron2+could be readily extracted from leaf tissue with aqueous solutions of the chelating agents OPh (1,10‐o‐phenanthroline) and PDTS [ferrozine; 3‐(2‐pyridyl)‐5,6‐bis‐(4‐phenylsulfonic acid)‐1,2,4‐triazine]. Iron2+values did not increase when leaf tissues were extracted more than 30 minutes. The first two extractions of the same tissue yielded higher Fe2+values than subsequent extractions. After the third extraction of the same tissue, Fe2+remained relatively constant. Even after seven extractions of the same tissue, some Fe2+could be extracted which indicated that some iron (Fe) was probably being converted to Fe2+with each extraction.

ISSN:0190-4167    

DOI:10.1080/01904168409363178

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The Iron Index has been developed to permit its application to the diagnosis and correction of iron chlorosis in culture growth. The stress in the ratio Fe‐Mn‐Zn enables us to diagnose deficiences with respect to some of these elements in the absence of visual signs. Both Iron Index and ratio Fe‐Mn‐Zn, P/Fe, Ca/Fe, Mn/Fe and Zn/Fe were applied to the nutritional research into several lots of walnuts (Juglans regiaL.) autochthonous from Sierra Nevada, Spain, in the same climatic and edaphologic conditions. These walnuts were sampled from the time their leaves were completely developed to their old age. Leaves were analysed and the mentioned index and equilibriums determined, being possible to verify the metabolic fluctuations and their correspondence with the morphological state in which the plants were every instant. There are no significant differences among each lot. They initially present very high nutritional levels, then they get stabliized, and decline abruptly later on. We deduce that during the autumn‐winter season the trees don't interrupt the absorption of nutrients, since at the beginning of the new cycle they presentveryhigh levels again. The equilibrium period coincides with that of the fruit formation.

ISSN:0190-4167    

DOI:10.1080/01904168409363179

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Potassium fertilization at rates of 135 to 405 mg K / kg soil ameliorated iron chlorosis in peanuts grown in an extremely calcareous soil (63% CaCO3); such treatments doubled and tripled chlorophyll contents. Potassium availability in soils was important in achieving this effect. K2SO4was found to be more effective than KCl. These results are attributed to the cation‐anion balance of ion uptake and consequent rhizosphere acidity.

ISSN:0190-4167    

DOI:10.1080/01904168409363180

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor