Effect of Zeolite and Foliar Application of Selenium on Growth, Yield and Yield Component of Three Canola Cultivar under Conditions of Late Season Drought Stress

Abstract

In order to study the effect of zeolite soil application and selenium foliar application on growth, yield and yield components of three canola cultivar under conditions of late season drought stress an experiment was conducted in two growing seasons in 2006 and 2007. Site study was a field of Seed and Plant Improvement Institute, Karaj, Iran. The experimental design was a Randomized Complete Block arrangement in factorial split plot with three replications. Irrigation factors were chosen at two levels, included complete irrigation and irrigation holding at stem elongation stage. Zeolite was used at two levels, non application and 10 ton per hectare. Also, selenium was sprayed at three concentrations, 0, 15 and 30 gr per liter from sodium selenate. These treatments were randomized in main plots while three canola cultivars (‘Zarfam’, ‘Okapi’ and ‘Sarigol’) were randomized in sub plots. The results showed that the main effects of different irrigation levels have a significant effect on all traits and drought stress decreased significantly all traits. Foliar application of selenium had a significant and additive effect on plant height, number of pods per plant, number of seeds per pod, seed yield, biological yield, harvest index and oil yield. There was a significant difference between zeolite application and non-application on all traits except oil percent and harvest index. It was shown that canola cultivars were different in all of the studied traits. Comparison of means showed that four critical traits, respectively the seed yield, biological yield, harvest index and oil yield were affected by experimental treatments. Different cultivars have different responses under unlike conditions inside upon traits. Under different treatment conditions especially drought stress, zeolite and selenium application have a positive and significant effect on traits related to yield. In finally, zeolite and selenium application in dry lands that are exposure to late season drought stress can be helpful for yield improvement and prevention of decreasing yield.