caa a22 4500 477112293 CHVBK 20180405111612.0 cr unu---uuuuu 170330e19960601xx s 000 0 eng 10.1007/BF02185570 doi (NATIONALLICENCE)springer-10.1007/BF02185570 Effects of waterlogging on chickpeas II. Possible causes of decreased tolerance of waterlogging at flowering [Elektronische Daten] [A. Cowie, R. Jessop, D. MacLeod] Waterlogging tolerance of chickpeas was found, in earlier work, to decrease sharply at flowering. Three experiments were performed to attempt to explain the mechanisms involved in this response. In the first, a range of treatments was imposed to modify the plant's source/sink relationships, as carbohydrate supply and partitioning were considered possible determinants of waterlogging tolerance. Plants from which buds were removed showed the most rapid recovery after waterlogging. Defoliation immediately before waterlogging reduced the rate of recovery. Application of benzyladenine plus gibberellic acid prior to waterlogging delayed stomatal closure and leaf senescence, inhibited apical growth and stimulated axillary growth. The second experiment aimed to confirm the influence of bud removal and to determine whether waterlogging tolerance is correlated with carbohydrate supply. Treatments comprised two sowing times, ten days apart, and two bud treatments (retained and removed). Waterlogging was imposed when older plants had been flowering for seven days and younger plants were in bud. Waterlogging caused soluble sugars to accumulate in the lower stem, suggesting that a deficiency of assimilates did not contribute to waterlogging injury. Similarly, waterlogging increased nitrogen concentration in the stem, through mobilisation from senescing leaves. Bud removal enhanced leaf survival and reduced mortality rate after waterlogging; it also increased starch concentration in the lower stem, indicating that storage of assimilates decreased in flowering plants. However, across all treatments, starch concentration was not correlated with waterlogging tolerance. In the third experiment, the effect of the senescence-promoting factor ethylene on preflowering and flowering plants was assessed, using the ethylene-releasing agent ethephon. Ethephon reduced growth to a slightly greater extent when applied prior to flowering than at flowering. There was no evidence that inadequate supply of carbohydrates or nitrogen in the stem, or increased sensitivity to ethylene, contributed to waterlogging intolerance in flowering chickpea plants. Kluwer Academic Publishers, 1996 carbohydrate nationallicence chickpea nationallicence Cicer arietinum nationallicence ethylene nationallicence flowering nationallicence physiological age nationallicence starch nationallicence waterlogging nationallicence tolerance nationallicence Cowie A. Department of Agronomy and Soil Science, University of New England, 2351, Armidale, NSW, Australia aut Jessop R. Department of Agronomy and Soil Science, University of New England, 2351, Armidale, NSW, Australia aut MacLeod D. Department of Agronomy and Soil Science, University of New England, 2351, Armidale, NSW, Australia aut Plant and Soil Springer Netherlands; gopher://gopher.wkap.nl 183/1(1996-06-01), 105-115 0032-079X 183:1<105 1996 183 11104 https://doi.org/10.1007/BF02185570 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02185570 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Cowie A. Department of Agronomy and Soil Science, University of New England, 2351, Armidale, NSW, Australia aut NATIONALLICENCE 700 1- Jessop R. Department of Agronomy and Soil Science, University of New England, 2351, Armidale, NSW, Australia aut NATIONALLICENCE 700 1- MacLeod D. Department of Agronomy and Soil Science, University of New England, 2351, Armidale, NSW, Australia aut NATIONALLICENCE 773 0- Plant and Soil Springer Netherlands; gopher://gopher.wkap.nl/ 183/1(1996-06-01), 105-115 0032-079X 183:1<105 1996 183 11104 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer