-Cabetas, M.J. 2012 Physiological and biochemical parameters controlling waterlogging stress tolerance in Prunus before and after drainage Physiol. Plant. 144 357 368 Bailey-Serres, J. Cho Lee, S. Brinton, E. 2012 Waterproofing crops: Effective flooding
effects created by plagiotropic growth form relative to BC and MC and potentially reduced floodtolerance relative to BC. The greater tolerance of BC to flooding may preclude major gains in salt tolerance improvement for use in coastal wetland restoration
periodic inundation of the root zone, and traditional thinking may suggest that only taxa adapted to upland sites will offer increased drought tolerance. However, many riparian habitats fluctuate between seasonal inundation and drought ( Hodges, 1998
Growth and physiological responses of Intsia bijuga trees to flooding were determined in a series of five container experiments to assess the relative tolerance of this species to flooding. The first measurable response to flooding was reduced leaf gas exchange, which began within 5 to 6 days of the onset of flooding. Development of hypertrophied lenticels at the water line and paraheliotropic leaflet movement were evident by 17 days of flooding. Emergence of adventitious roots on the stem above the water line began after about 30 days of flooding. Leaflet abscission was greatly accelerated by flooding. After more than 3 months of flooding, regrowth of roots, stems, and leaves began within two weeks of draining the medium. The data and observations support a relative ranking of moderate flood tolerance for Intsia bijuga.
diversity of salinity tolerance of cultivars of seashore paspalum in general is also limited ( Lee et al., 2005 ). With this in mind, a container-oriented investigation involving established ‘SeaDwarf’ seashore paspalum was conducted at Edison College in
The effects of flooding calcareous soil on physiology and growth have been studied for several subtropical and tropical fruit crops including avocado (Persea americana Mill.), mango (Mangifera indica L.), carambola (Averrhoa carambola L.), and several Annona species. In calcareous soils that have a high pH, short-term flooding can actually be beneficial to subtropical and tropical fruit crops by increasing the solubility of particle-bound nutrient elements such as Fe, Mn and Mg due to flooding-induced decreases in soil pH. Additionally, flooding reduces the redox potential in the soil, resulting in Fe being reduced from Fe3+ to Fe2+, which is the cation metabolized by plants. As with other woody perennial crops, one of the early physiological responses of subtropical and tropical fruit trees to flooding is a decrease in stomatal conductance and net CO2 assimilation. If the flooding period is prolonged, lack of O2 (anoxia) in the soil results in a reduction of root and shoot growth, wilting, decreased nutrient uptake and eventual death. The flooding duration required to cause tree mortality varies among species, among cultivars within species, and with environmental conditions, particularly temperature. Several tropical and subtropical fruit crops have anatomical or morphological adaptations to tolerate prolonged flooding, such as development of hypertrophied stem lenticels, adventitious rooting or formation of porous aerenchyma tissue. For grafted trees, flooding-tolerance is conferred by the rootstock and not the scion. Therefore there is a possibility to increase flood tolerance of subtropical and tropical fruit crops by identifying or developing flood-tolerant rootstocks.
A circulating system with sufficient versatility to permit monitoring and control of solutions in the flooded root rhizosphere is described. The system circulates anaerobic solutions around plant roots or can be used to simulate the type of flooded environment necessary for anaerobic bacterial activity. The composition of the solution can be monitored before, during, and after contact with the roots. Oxygen deficiency per se was relatively harmless to citrus roots, whereas severe root damage occurred from exposure to < 3 ppm total sulfides at pH 6 for 7 days. Tolerance to flooding of rough lemon appears to be associated with tolerance to injury by H2S.
One-month-old seedlings of 20 entries of tomato (Lycopersicon esculentum Mill.) were subjected to flooding for 3 days, or drenched with ethanol or (2-chloroethyl)phosphonic acid (ethephon) solution. Flooding reduced stem growth and leaf chlorophyll content of thelower leaves and promoted epinastic curvature of leaf petiole and adventitious roots. Application of ethephon elicited a response similar to that of flooding. No prominent morphological and physiological changes were observed from ethanol application. Flooded plants show increases in their endogenous free proline pool, which can be reduced by the withdrawal of flooding. Flooded L-123 plants, the most tolerant entry, accumulated the least free proline among three entries tested. Proline level appeared to indicate the intensity of oxygen deficiency during soil flooding by reflecting oxygen supply, and could serve as in indicator in relating plant injury to flooded conditions. The tolerance of L-123 to soil flooding, at least in part, depends on its ability to transport oxygen from the aerial part to the root.
Young ‘Ruby Red’ grapefruit (Citrus paradisi Macfad.) trees on 20 rootstocks were tested for chloride (Cl−) and boron (B) tolerance by trickle and flood irrigation methods. Hybrids with trifoliate orange parentage had high, lemons moderate, and Alemow and limes low Cl− levels. Citrumelo W-2, the limes, most of the lemons, and Alemow had Cl− tolerance similar to that of Cleopatra mandarin, a Cl−-tolerant rootstock. Trees had similar vigor and Cl− toxicity symptoms in the trickle and flood treatments but took up more Cl− in the flood. All rootstocks except the two Alemows accumulated excessive B. The rootstocks took up similar amounts of B in the flood and trickle treatments but were more vigorous and exhibited more B toxicity symptoms in the latter.
Photosynthesis and transpiration rates of seedlings of 4 citrus rootstocks under flooded conditions were measured over a 10-day period. For all rootstocks photosynthesis and transpiration decreased, but photosynthesis decreased relatively less than transpiration. Stomatal closure is inferred to account in part for the reductions observed.
Flooding did not increase ethanol concentration in either tops or roots, suggesting that ethanol is not an end-product of. anaerobic respiration in citrus seedlings. Only in the neutral soil was rough lemon (Citrus limon L. Burm. f.) found to be more tolerant to short-term flooding than ‘Cleopatra’ mandarin (Citrus reticulata Blanco) and trifoliate orange (Poncirus trifoliata L. Raf.). Tolerance to flood injury was greater at a soil pH of 7 than 4.5.