IMPROVING THE PERFORMANCE OF MAIZE (Zea mays L.) BY SILICON APPLICATION UNDER DROUGHT CONDITION

Abstract

Water shortage on our globe has very deleterious effects on food security. Judicious use of water for crops seems very wise in the current scenario of water scarcity. Huge research work is required to investigate how can we grow crops with less amount of water? To determine the solution for such kinds of problems this research project was designed. The research project entitled, “Improving the performance of maize (Zea mays L.) by silicon application under drought condition” was carried out at Postgraduate Agricultural Research Station (PARS), University of Agriculture, Faisalabad, Pakistan. In the first pot experiment screening of maize hybrids (P-33H25, S-8441, FH-985, ICI-8288, YH-1921, R-3333, FH-963, FH-810) against drought was carried out. Moisture levels of 100%, 80% and 60% field capacity were maintained. From this experiment the most tolerant (P-33H25) and most sensitive (FH-810) maize hybrids against drought were screened out. In the second pot experiment four silicon levels (0, 50, 100 and 150 mg/kg) were optimized under moisture levels of 100% and 60% field capacity maintained. The optimized silicon level (100 mg/kg) was selected for further study. The third pot experiment was conducted to investigate the improvement in drought stressed maize hybrids by exogenous application of silicon. The two selected hybrids from the first experiment were sown under two moisture regimes (100% and 60% field capacity). In this experiment silicon level i.e. 100 mg/kg (optimized in experiment II) was used. Drought was imposed two weeks after emergence and maintained. The fourth experiment was conducted under field condition with two selected maize hybrids (P-33H25 and FH- 810) and two irrigation regimes (100% and 60% FC) from the 1 st experiment and two silicon levels (0 mg/kg and 100 mg/kg) from 2 nd experiment. In this experiment moisture application was maintained at 100 or 60% field capacity. In this experiment the maize crop was sown for two years 2010 and 2011 in both seasons i.e. spring and autumn. The data regarding morphological, physiological and biochemical parameters were recorded by following standard procedures. The analysis of data from the first experiment showed that mild and severe drought had deleterious effects on various morphological and physiological parameters. However, root fresh and dry weight enhanced under mild drought while decreased under severe water limited condition. On the basis of dry matter production the most drought tolerant (P-33H25) and drought sensitive (FH-810) maize hybrids were screened out. In the second experiment best suited silicon level (100 mg/kg) was optimized on the basis of dry matter production. In the third experiment drought severely affected the morphological, physiological and biochemical attributes of maize hybrids. However, silicon application improved the various agronomic attributes, yield and yield components. The same study was conducted in field as that of third experiment to investigate the effect of silicon on maize hybrids grown under water limited condition. Significant effects of silicon application were observed on various agronomic, physiological, yield and yield related parameters. However, further research is required to investigate the silicon mediated drought tolerance in maize hybrids.