Effect of Radiation and Temperature on Efficiency of Cereal Leaves during Grain Growth |
| |
Authors: | WELBANK P J; WITTS K J; THORNE GILLIAN N |
| |
Institution: | Rothamsted Experimental Station Harpenden, Herts |
| |
Abstract: | Grain: leaf ratio, G (the ratio of grain yield to leaf areaduration between ear emergence and maturity), in 15 experimentson wheat and barley in different seasons (Group A experiments)was highly correlated with mean daily radiation, R, mean dailytemperature, Tµ, and mean daily maximum temperature, Tmax,during the grain growth period. The regression of G on R accountedfor 81 per cent of the variance of G, and introducing Tµto the regression significantly increased this to 88 per cent.The regression of G on Tmax alone accounted for 87 per cent,perhaps because Tmax effectively integrates radiation and temperature. When R was varied artificially by shades in two experimentson wheat in different years (Group B experiments) the relationshipbetween G and R was approximately linear in both, but the slopeof the line was less in one year, when R and temperature wereless, than in the other. For this second year, when R and temperatureswere about the middle of the ranges found in Group A experiments,the calculated relationship agrees with the Group A resultsafter correcting values of G for differences of Tu from itsvalue in the shading experiment. A formula relating G and Rderived from the results of both Group B experiments and theobserved correlation of R and temperature in the field, assumingthat the regression of G on R depends on temperature, agreeswith the relationship between G and R in the Group A experiments. It is concluded that differences in radiation and temperatureare about equally responsible for the differences in G foundbetween seasons. The positive effect of temperature on G suggeststhat factors other than leaf photosynthesis, e.g. translocationrate or capacity of the grain to accumulate carbohydrate, areimportant in determining G. |
| |
Keywords: | |
本文献已被 Oxford 等数据库收录! |
|