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21. |
Nitric acid‐ and o‐phenanthroline‐extractable iron for diagnosis of iron chlorosis in citrus lemon trees |
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Communications in Soil Science and Plant Analysis,
Volume 29,
Issue 7-8,
1998,
Page 1035-1043
MunirJamil Mohammad,
Husam Najim,
Saeb Khresat,
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摘要:
Plant analysis for total iron (Fe) is frequency used for diagnosis of Fe‐deficiency chlorosis. However, chlorotic plants frequency contained similar or higher amount of total Fe than the healthy green plants. The objectives of this study were to (i) determine if Fe chlorosis in citrus lemon can be diagnosed by total or active Fe and can be related to the degree of chlorosis, and (ii) determine the optimum extraction time and ratio of extracting solution to plant sample for extracting the active Fe. Leaf samples of different degrees of Fe chlorosis were sampled from different citrus lemon trees from three different sites. Total Fe was extracted with nitric acid (HNO3) and active Fe with o‐phenanthroline from lemon leaves. An extraction time of 20 and 45 hours and the ratios of the extractor to the sample of 5:l, 10:1, and 20:1 were investigated. The results indicated that an extraction time of 20 hours is enough for extracting the active Fe from citrus lemon leaves by o‐phenanthroline. The amount extracted by all ratios (5:1, 10:1, and 20:1) were detectable and at the same time similarly and consistency showed the differences in degrees of chlorosis in all plant samples. Total Fe content was always higher in moderately and severely chlorotic leaves compared to the green leaves and was not related to the degree of chlorosis. Therefore, total Fe cannot be used as a criteria to differentiate between the Fe‐deficient and non‐deficient plants. On the other hand, active Fe tended to decrease with the increase in the degree of chlorosis. The ratio of active to total Fe was calculated and was found to be closely correlated with the degree of chlorosis. This clearly illustrates the failure of plant analysis for total Fe and the effectiveness of active Fe and/or the ratio of active to total Fe for diagnosing Fe chlorosis.
ISSN:0010-3624
DOI:10.1080/00103629809370005
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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22. |
Changes in soil fertility and leaf nutrient concentration at a sugar cane plantation in Papua New Guinea |
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Communications in Soil Science and Plant Analysis,
Volume 29,
Issue 7-8,
1998,
Page 1045-1060
AlfredE. Hartemink,
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ISSN:0010-3624
DOI:10.1080/00103629809370006
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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23. |
Editorial board |
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Communications in Soil Science and Plant Analysis,
Volume 29,
Issue 7-8,
1998,
Page -
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PDF (41KB)
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ISSN:0010-3624
DOI:10.1080/00103629809369984
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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