Premium
In‐vitro‐cultured subclover root can develop Fe‐deficiency stress response
Author(s) -
Wei Liangchou,
Ocumpaugh William R.,
Loeppert Richard H.
Publication year - 1997
Publication title -
physiologia plantarum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.351
H-Index - 146
eISSN - 1399-3054
pISSN - 0031-9317
DOI - 10.1111/j.1399-3054.1997.tb00025.x
Subject(s) - trifolium subterraneum , cultivar , horticulture , shoot , in vitro , biology , chemistry , zoology , botany , agronomy , biochemistry , pasture
The Fe‐deficiency stress response is induced in most plants under Fe‐deficient conditions, but whether the shoot and/or the root control development of the stress response is not known. The objectives of the present study were to determine whether in‐vitro‐cultured subclover roots can develop Fe‐deficiency stress response and to examine this approach as a possible screening technique for Fe‐deficiency resistance. One‐cm long root tips of subclover seedlings were cultured in modified White's medium without (‐Fe) or with (+Fe) 100 μ M Fe 3+ EDTA. Root Fe 3+ reduction and H + release were evaluated. On the first day after transfer to the ‐Fe medium, the Fe‐deficiency‐resistant cultivar Koala ( Trifolium brachycalycinum Katzn. and Morley) started to release H + , resulting in a decrease in pH of the culture medium, while the susceptible cultivar Karridale ( T. subterraneum L.) did not release H + until the second day. The H + ‐release rate of the ‐Fe Koala was approximately twice as high as that of the ‐Fe Karridale for the first 4 days of ‐Fe treatment. Both Koala and Karridale reached their highest H + ‐release rates on the fourth day after ‐Fe treatment initiation. The +Fe Koala released H + after several days of culture, but the H + release of the ‐Fe Koala was severalfold greater than that of the +Fe Koala. The implicit correlation between H + release and Fe‐deficiency resistance was substantiated by using a series of subclover cultivars with a range of susceptibilities to Fe deficiency. The pH of the ‐Fe culture media of the series of cultivars was positively correlated to their Fe‐chlorosis scores reported in previous research. The results of the present study indicate that root itself has the full ability to develop Fe‐deficiency stress response and the response is dependent on the root Fe status. The results also suggest that root culture could be used as a simple and efficient alternative technique for screening germplasm for Fe‐deficiency resistance.