Effect of methanol on radiation use efficiency, coefficient extinction and optimum leaf area index of sugar beet (Beta vulgaris)

In order to evaluate light extinction coefficient and radiation use efficiency in response to foliar application of on sugar beet a study was performed using completely randomized block design with factorial treatments in 3 replication at research farm of Islamic azad university, Karaj branch(Maahdasht) in 2008-2009. Aqueos solutions 0 (control), 7, 14, 21, 28, 35 %(v/v) methanol and each solution contained 0.2% glycine. These solutions was sprayed 3 times in two week inervals on foliage parts of sugar beet. The plots were sampled 6 times during growing seaseon. Results of the experiment indicated that there was significant differences between effects of solutions on radiation use efficiency. The comparison of 21% (v/v) and 0 (control) indicated that radiation use efficiency was increased about 43 percent in 21%(v/v) also the maximum optimum leaf area index that was gained the maximum CGR related to 21%(v/v). There was not significant differences between effects of solutions on light extinction coefficient. Light extinction coefficient was decreased in comparison with other levels of solution by 21 %(v/v).