Heat tolerance in food legumes as evaluated by cell membrane thermostability and chlorophyll fluorescence techniques

Abstract

The genotypic variation for heat tolerance in chickpea, groundnut, pigeonpea, and soya bean was evaluated by testing membrane stability and photosystem (PS II) function in leaves at high temperatures . The legumes could be ranked from heat-tolerant to sensitive in the order : groundnut, soya bean, pigeonpea and chickpea. The damage to cell membranes (as reflected by an increased leakage of electrolytes) and PS II (as reflected by a decrease in the ratio of variable to maximum fluorescence) was less, and recovery from heat stress was faster in groundnut than in other crops . Prior exposure of plants to 35 °C for 24 h led to a reduced leakage of electrolytes at high temperatures in all crops but the differences among legumes were consistent . Substantial genotypic variation for heat tolerance was found in all legumes . Membrane injury was negatively associated with specific leaf weight in groundnut (r= -0 .69**) and soya bean (r= -0 .56**) but not in the pulses . Electrolyte leakage and fluorescence ratio were negatively correlated in all legumes . The potential use of electrolyte leakage and fluorescence tests as screening procedures for breeding heat-tolerant legumes is discussed .Abbreviations: RI -relative injury ; Fo -initial fluorescence ; Fm -maximum fluorescence ; Fv -variable fluorescence ; PS II -photosystem II ; PAR -photosynthetically active radiation

Global synthesis of drought effects on cereal, legume, tuber and root crops production: A review

“…The responses of different crops to heat stress, however, co-varied with species, similar to our findings regarding drought (Daryanto et al, 2015, in review-a, b). Different levels of heat tolerance across different legume species, for example, occurred with groundnut having greater heat tolerance compared to soybean, pigeon pea, and chickpea (Srinivasan et al, 1996). Mechanisms at the cellular level appeared to be important for higher heat tolerance in groundnut than in other legumes as it experienced faster recovery from cell membrane and photosystem II (PSII) damages (Srinivasan et al, 1996).…”

“…Different levels of heat tolerance across different legume species, for example, occurred with groundnut having greater heat tolerance compared to soybean, pigeon pea, and chickpea (Srinivasan et al, 1996). Mechanisms at the cellular level appeared to be important for higher heat tolerance in groundnut than in other legumes as it experienced faster recovery from cell membrane and photosystem II (PSII) damages (Srinivasan et al, 1996). Indeed, a more recent finding suggested that screening for heat-tolerant legumes (i.e., chickpea) and potentially other crop groups was based on membrane stability, photosynthetic efficiency, and pollen germinability at high temperature (>35°C) (Basu et al, 2009).…”

Development of laboratory‐based methods for assessing seedling thermotolerance in pearl millet

“…The leakage of electrolytes into a bathing medium after exposure to stress provides an indication of the cellular membrane damage caused by that stress; the more damage caused by the stress, the more solutes will leak into the bathing medium. Electrolyte leakage has been used to assess stress-induced damage in many species (Sullivan, 1972;Martineau et aL, 1979;Blum & Ebercon, 1981;Chen, Shen & Li, 1982;Saadalla, Quick & Shanahan, 1990a;Saadalla, Quick & Shanahan, 19906;Tahir & Singh, 1993;Srinivasan et aL, 1996). The possibility of using electrolyte leakage to assess seedling thermotolerance in both pearl millet and sorghum seedlings has been investigated here in detail in conjunction with both field screening and also the measurement of seedling growth following exposure to high temperature.…”

Heat Stress Related Physiological and Metabolic Traits in Peanut Seedlings

“…During abiotic stress, lipid peroxidation can cause severe membrane injury (MI) and as such, it can be measured to assess the degree of stress in crops including peanuts (Bajji et al, 2002;Blum and Ebercon, 1981;Srinivasan et al, 1996). MI and the F v /F m ratio have previously been used in screening peanut genotypes for salt, heat, and drought stress tolerance (Lauriano et al, 2000;Qin et al, 2011;Srinivasan et al, 1996). Peanut seedlings exposed to a 40/35 C temperature treatment in this study showed on average 18% increased MI compared to control plants (Table 2).…”