The Development in Time of Stress Effects in Two Species of Glycine Differing in Sensitivity to Salt

Abstract

SummaryFor two Glycine species (wightiit and tomentella) varying in sensitivity to salt the development of stress over a range of salinities was traced through changes in growth, water content, and chemical composition of tissues of different type and age.The general picture of salt stress appears to be one of immediate growth reduction through an initial water stress approximately proportional to the concentration of salt applied. At 40 m-equiv/l of sodium chloride osmotic adjustment apparently occurs, control growth rate is regained, and, the data suggest, is likely to be maintained without significant tissue injury developing. At 80 m-equiv/l of sodium chloride, the trends in tissue water content indicate that some osmotic adjustment may occur, particularly in the older leaves, but at this level of salinity and especially at 160 m-equiv/l of sodium chloride the rapid and excessive chloride accumulation injures the leaves and growth rate falls progressively in relation to that of the control. The detrimental effects of salt on nutrient and water content are more pronounced in the young leaf tissue developing during salt treatment than for the older leaves.Species difference in sensitivity appears associated with the leaf injury phase of salt stress. It is thought that leaf injury is greater in tomentella than wightii because of the faster initial increase in chloride concentration in tomentella, particularly in the younger leaf tissue, and also that a reduced potential for protein synthesis in these leaves in tomentella may have aggravated the situation.Analysis of time trends in growth rate and other plant attributes, a technique largely ignored in salt resistance studies, helps to distinguish between the osmotic and toxic effects of ions.

sas1, an Arabidopsis Mutant Overaccumulating Sodium in the Shoot, Shows Deficiency in the Control of the Root Radial Transport of Sodium

“…Thus, Na ϩ overaccumulation is an intrinsic characteristic of sas1 plants. In this respect, sas1 mutants behave in a different manner than dwarf lines of rice (Yeo and Flowers, 1986;Yeo et al, 1990) or Glycine tomentella (Wilson et al, 1970), which overaccumulated Na ϩ and Cl Ϫ , respectively, compared with nondwarf or more vigorous lines.…”

“…Thus, Na ϩ overaccumulation is an intrinsic characteristic of sas1 plants. In this respect, sas1 mutants behave in a different manner than dwarf lines of rice (Yeo and Flowers, 1986;Yeo et al, 1990) or Glycine tomentella (Wilson et al, 1970), which overaccumulated Na ϩ and Cl Ϫ , respectively, compared with nondwarf or more vigorous lines.Detailed analysis of Na ϩ accumulation in different organs of sas1 plants or under different culture conditions, including the culture of calli (Table 1), led to the conclusion that long-range Na ϩ transport was modified in sas1 mutants. Mass flow due to transpiration plays a major role in translocating Na ϩ to the aerial organs.…”

Effect of NaCl on emergence and growth of a range of provenances of Eucalyptus citriodora, Eucalyptus populnea, Eucalyptus camaldulensis and Acacia salicina

“…Although numerous studies have examined effects of NaCl on plant growth (e.g. Wilson et al, 1970;Bernstein, 1975;Munns, 1993;Munns, 2002) little information was available on levels of salt likely to limit establishment and/or growth of eucalypt and acacia species native to central Queensland. Experiments were undertaken to address this.…”

Physiological studies on salinity VI. Changes in water content and mineral composition of some plants over a range of salinity stresses

“…Meiri and P o l j a k o f f -M a y b e r 3° and Meiri et al 31 32 observed a remarkable decrease in water content in chloride salinated bean plants, and also W i l s o n et al 43 in the young leaf tissue of Glycine species (Wightii and tomentella) during salt treatment. The percentual change between normal and 6000 for wheat is greater than for radish.…”