Germination Characters and Seed Reserve Mobilization During Germination of Different Wheat Genotypes Under Variable Temperature Regimes

Abstract

A laboratory experiment was conducted in the Crop Botany Laboratory , a t Bangabandhu Sheikh Mujibur Rahman Agricultural University, Salna, Gazipur during 15 October to 15 November, 2001 to study the influence of three temperature regimes (15OC, 25OC and 35OC) on germination characters and seed reserve qobilization in six wheat genotypes. Three heat tolerant ( Aghrani, Kanchan and CB-30) and three heat sensitive (Sonora, CB-24 and CB-34) wheat genotypes were used as study material. Speed of germination expressed a s rate of germination, coefficient of germination and germination vigor index was found to be increased with increasing temperature from 15 O C to 35OC in all wheat genotypes, but heat tolerant ability based on speed of germination was not found. Generally shoot and root growth of HS genotype in relation to length and dry weight were affected more than those of HT genotypes a t high temperature. The amount of seed reserve loss a s respiration increased from 25OC to 35OC in all genotypes, but the increment was higher in Sonora (14.1%) and CB-24 (13.21%), moderate in Kanchan (6.36%), CB-30 (5.22%) and CB-34 (4.95%) and lowest in Aghrani (2.03%). At 15OC, the amount of seed reserve loss a s respiration was also increased from that a t 25°C in all genotypes except in Aghrani and CB-30. But again the increment was higher in Sonora, CB-24 and CB-34 (2.79 to 8.84%) than that of Kanchan (1.67). In case of ~~h r a n i and CB-30, it even decreased. At 25OC temperature the seed reserve mobilization efficiency was significantly higher than that a t 15OC and 35OC in all wheat genotypes. But the heat sensitive genotypes had higher efficiency (2.58 to 3.48 glg) than that of the heat tolerant genotypes (1.99 to 2.09 gig) a t 25OC. Based on reduction of efficiency both a t 15OC and 35OC from that of 25OC, Sonora, CB-24 and CB-34 (HS) were found more affected than Aghrani, Kanchan and CB-30 (HT).

Effect of Different Temperatures on Germination and Early Seedling Growth of Grass Pea (Lathyrus Sativus L.)

“…Barpate et al (2015) reported that the low temperatures caused delayed germination and slow seedling growth, increased temperature from 4 to 30° C had positive impact on fresh shoot weight and dry root weight of cotton seeds (Gossypium hirsutum L.). Buriro et al (2011) and Hassan et al (2004) claimed that the increase in temperature promoted shoot fresh weight and shoot dry weight of wheat (Triticum sp.) seedlings from 10 to 35°C.…”

Biochemical and physiological constituents and their correlation in wheat (Triticum aestivum L.) genotypes under high temperature at different development stages

“…As the temperature increased the germination of seeds decreased in both genotypes but the ratio of decreased in heat susceptible genotype J-2010-11 was more. Germination characters increased with increasing temperature from 15 to 35°C in all wheat genotypes but heat tolerant ability was not based on speed of germination (Hasan et al, 2004). Germination characteristics in heat tolerant cultivars increased with increasing temperature as compared to heat sensitive cultivars (Sikder and Paul, 2010).…”

“…The seedling vigor is adversely affected by heat stress (36°C) which resulted in reduced shoot and root length (Grass and Burris, 1995). Generally shoot and root growth of heat susceptible genotype in relation to length is affected more than thoseof heat tolerant genotype at higher temperature-35°C (Hasan et al, 2004).…”

Temperature Regimes on Seeds Germination and Growth Parameters of Wheat (Triticum aestivum L.) Genotypes at Early Seedling Stage

“…Mahan et al (1995) observed that thermal stress influence morphology and physiology of the root system which may influence water movement through the plant. Hasan et al (2004) also reported that from a low temperature to high temperature (15 to 30 °C), the shoot length of wheat seedlings showed an increasing tendency.…”