Proline accumulation and nitrate reductase activity in contrasting sorghum lines during mid‐season drought stress

Abstract

Peacock, J. M. 1988. Proline accumulation and nitrate reductase activity in contrasting sorghum lines during mid-season drought stress. -Physiol. Plant. 74: 418-426.Six lines of sorghum {Sorghum bicolor L. Moench) with differing drought resistance (IS 22380, ICSV 213, IS 13441 and SPH 263, resistant and IS 12739 and IS 12744, susceptible) were grown under field conditions in the semi-arid tropics and analysed for proline and nitrate reductase activity (NRA; EC 1.6 6.1) during a mid-season drought. The resistant lines accumulated high levels of proline, while the susceptible lines showed no significant proline accumulation. Most of the proline was accumulated after growth of the plants had ceased. In a separate greenhouse experiment, most of the proline was found in the green rather than the fired portions of leaves. The levels returned to that of irrigated controls within 5 days of rewatering. Proline levels increased as leaf water potential and relative water content fell, and there was no apparent difference among the different sorghum lines with change in plant water status. Susceptible lines accumulated less proline than resistant lines as leaf death occurred at higher water potentials. Proline accumulation may, however, contribute to the immediate recovery of plants from drought. Leaf NRA reached high levels at about 35 days after sowing in both the stressed and irrigated plants, after which it declined. The decline in NRA was more pronounced in the stressed than in the irrigated plants and closely followed changes in the growth rate. Upon rewatering, NRA increased several-fold in all the lines and, in contrast to proline accumulation, genotypic differences in NRA were small, both during stress and upon rewatering. The high sensitivity of NRA to mild drought stress was reflected in the rapid decline of activity with small changes in leaf water potential and relative water content. The results are discussed in the light of a possible role for proline during recovery from drought, and the maintenance of NRA during stress and its recovery upon rewatering.

Comparative study of proline accumulation of Some varieties of Durum Wheat (Triticum durum Desf.) under water Stress Conditions.

“…The results showed that Beni Mestina variety is highly resistant with a production rate of 133. Many studies report that proline accumulated in plants under unfavorable conditions (Sivaramakrishnan et al, 1988) which reflects the character of resistance to water stress (Greenway …”

Proline as a probable biomarker of cold stress tolerance in Sorghum (Sorghum bicolor)

“…In this regard, it has been reported that the accumulation of proline in transgenic plants (Surender Reddy et al, 2015) can mitigate significantly the damage caused by salinity. Moreover, in wildtype plants, it has been observed that genotypes with a higher tolerance to drought stress accumulate a higher concentration of proline on tolerant plants compared to susceptible plants (Sivaramakrishnan et al, 1988). In contrast, reactive oxygen species accumulation was consistently higher in plants of the variety TX430 compared to the variety R19 reaching a more considerable difference in the phenological phase of five leaves.…”

Action de la salinité sur les teneurs en proline des organes juvéniles de trois lignées de fève (Vicia fabaL.)

“…'accumulation de composes organiques azotes comme Ia proline (1-Iubac et al, 1969;Stewart, 1979;Briens et Larher, 1982 ;Rodriguez et Heyser, 1988 ;Goldhirs et al, 1990). Cet acide amine est retenu par de nomhreux auteurs comme indicateur de Ia tolerance au froid, a Ia secheresse ou a Ia salinite (Flowers et Yeo, 1977;Calmes et al, 1985 ;Paquin et Pelletier, 1980) (Hubac et Guerrier, 1972 ;Hanson et al, 1979;Sivaramakrishnan et al, 1988) considerent que ! 'accumulation de Ia proline se produit lorsque Ia plante est en conditions defavorables.…”