Temperature induction response and accumulation of starch granules as indices to identify the thermotolerance of pulses at early growth stages

Abstract

In pulses, high temperature is a major limiting factor for yield decline. Tamil Nadu has a rich pulse germplasm with high genetic variability. Hence, the present study was designed to develop a technique to screen genotypes for high temperature tolerance. A rapid screening protocol was developed based on the principle of "acquired tolerance". Adapting this temperature induction response (TIR) technique to pulses, popular varieties of TNAU pulses of blackgram (VBG-07-001, VBG-08-003), redgram (CO-6, VBN-2) and soybean (CO-1, CO-2) were screened for thermotolerance. The challenging lethal temperature was standardized as 50°C for 3 hours at which 90 per cent of the seedling mortality occured. The induction temperature was standardized as 36°C to 40°C at which 48.3 per cent of growth reduction over control was noticed. Blackgram showed higher thermotolerance than other pulses in terms of survival percentage and seedling growth. Blackgram seeds showing contrasting behaviour to temperature stress tolerance namely VBG-07-001(tolerant) and VBG-08-003 (susceptible) were analysed for the accumulation and distribution of starch granules responsible for the grain filling under heat stress.

Evaluating thermotolerant sunflower genotypes with temperature induction response (TIR) technique

“…A similar study was conducted in other crops such as groundnut, cotton (Kheir et al, 2012), and banana (Vidya et al, 2017). In field conditions, plants acquire thermotolerance to go through subsequent LT as in pulses (Partheeban et al, 2017), sunflower (Senthil Kumar et al, 2007. The higher TSL of induced seedlings as a consequence of altered metabolism is seen in a sunflower (Senthil Kumar et al, 2007), Several physiological and biochemical processes occur in response to IT.…”

Winter-hardiness assessment in groundcovering roses by histochemistry

“…Nowadays, modern state of investigations in plant hardiness to both high and low temperatures implies application of advanced precision equipment, artificial environment chambers (biotrons); for many studies, model objects, usually herbaceous plants, are used [6][7][8][9]. That is of essential importance for profound understanding of acclimatization training mechanisms and cold stress withstanding, as classical histochemical analysis appears insufficient for the purpose.…”