Duration of Grain Filling and Kernel Weight of Wheat as Affected by Temparature¹

Abstract

Once kernels are set, cereal grain yields are proportional to kernel weight. Thus environmental effects on kernel size merit better understanding as a source of yield variability.Plant phenology was observed, environmental conditions were monitored, and kernel weights were determined for wheat during two seasons at 26°N. Lat. These observations provided data sets for relating mean daily temperature during grain filling (from the beginning of flowering to mealy ripeness of the kernels) to kernel weight and to duration of grain filling.The data indicate a 3.1 day shortening of grain filling per degree C increase in mean daily air temperature during grain filling which compares with 2.8 days C‐1 for seven studies reported in the literature. Kernel weight in this study decreased 2.8 mg kernel ‐1 C‐1 compared with 1.5 mg for each degree C increase in temperature for seven studies in the literature.We concluded that temperature is pacing plant senescence and that shortening the duration of grain filling is its common manifestation in commercial winter and spring wheats. Temperature, when in excess of about 15 C, apparently explains the dependence of 1,000 kernel weight on grain filling duration.The findings imply that genetic variability in plant senescence and grain filling rates need to be searched for and exploited to help stabilize the kernel size component of yield.

The climate of the zone of origin of Mediterranean durum wheat (Triticum durum Desf.) landraces affects their agronomic performance

“…This observation is consistent with the reported longer post-anthesis duration of early-anthesis wheat cultivars (Tewolde et al 2006). The large effect of the environmental conditions on grain filling duration observed in this study and reported by other authors (Wiegand and Cuellar 1981;Santiveri et al 2002) could explain why the 6 days of delay to the date of anthesis of landraces from Z4 compared with those of Z1 were reduced to 4 days of difference in the number of days at maturity. Accumulated ET 0 and relative humidity from anthesis to maturity in the climatic zone of origin were the most important traits in explaining grain filling duration, with both variables accounting for 64 % of variation in the length of this period.…”

Effect of High Temperature at Ripening Stage on the Reserve Accumulation in Seed in Some Rice Cultivars

“…Singletary et al ( 1994) reported that there is a linear decline in maize kernel weight and rice endosperm starch content as the grain filling temperature increases over 22 °C. In addition, studies with wheat and rice also showed that a negative linear relationship between grain-filling temperature and mature kernel weight (Wiegand and Cuellar, 1981;Tashiro and Wardlaw, 1991). Marcellos and Single ( 1972) demonstrated that the duration from anthesis to maturity was reduced by high temperatures in four wheat cultivars.…”

Spot blotch and terminal heat stress tolerance in south Asian spring wheat genotypes

“…U. R. ROSYARA et al Heat stress during GS3 (anthesis to maturity) mainly affects assimilate availability, the translocation of photosynthates to the grain, and starch synthesis and deposition in the developing grain. Increased mean temperature in the range of 12-26°C has been found to be associated with reduced grain filling (Wiegand and Cuellar, 1981). TKW has been reported to be most affected by high spot blotch severity (Sharma and Duveiller, 2004;Rosyara et al, 2007), heat stress (Sharma et al, 2008) and spot blotch combined with heat stress (Sharma and Duveiller, 2004).…”