Effect of Animal Manure and Superabsorbent Polymer on Corn Leaf Relative Water Content, Cell Membrane Stability and Leaf Chlorophyll Content Under Dry Condition (Report‪)‬

Introduction Corn (Zea mays L.) is an important plant that is used as human food (20-25%), livestock and poultry feed (60-75%) and as raw material in industry (5%) (Emam, 2004). Corn is one of the best plants for producing green forage, silage forages and grain due to its high content of sugar and starch, as well as it yields more than 80 tone forage per hectares (Tajbakhsh and Pour Mirza, 2003), on the other hand, in Iran we have shortage in producing animal feeds, so, corn production is very important in Iran. The dearth of water is one of the important factors for corn production. Plant will experience water stress if transpiration is very high and available water decreases for roots (Ober and Sharp, 2003). The use of organic fertilizers including animal fertilizers and superabsorbent polymer is very effective in reducing drought stress effect and to improve the plants yield and stability in agriculture production. Plant reaction to drought stress is dependent on the intensity of water shortage. Plants have a short term or long term physiological respond to the drought stress. Changes in leaf relative water content and leaf chlorophyll content is a short term reaction to stress and it could be source adapting in drought stress condition (Ahmadi and Ceiocemardeh, 2004). Cell membrane stability is a source indicator of plant resistance to environmental stresses (Saneoka et al., 2004). Puor mousavi et al., (2007) and Costa-Franca et al., (2000) reported that leaf relative content in soybean and bean reduced by drought stress. Saneoka et al., (2004) in a research on Agrostis palustris reported that leaf osmotic potential reducing by nitrogen nutrition as a result of leaf water relative content increased. Also potassium nutrition increased leaf water relative under drought stress condition (Azizi and Rashed Mohasel, 1998). Leaf chlorophyll content is an important factor in determination of photosynthesis rates and dry mater production (Ghosh et al., 2004). Chlorophyll A in wheat decreased in heading and 20 days after anthesis and chlorophyll B decreased in heading stage only in drought stress condition (Ahmadi and Ceiocemardeh, 2004). Ommen, and Donnelly (1999) reported that chlorophyll content in wheat increased in flag leaf by drought stress in anthesis stage in comparison with non stress condition. The result of some researches showed that cell wall was destroyed by increasing fat content in cell wall in drought stress (Macarrone et al., 1995; Hieng et al., 2004). Blum and Ebercon 1981 found that cell wall in wheat has been resistance in drought stress condition. Cell membrane stability increased by drought stress in comparison with nitrogen fertilizer in bent plant; however cell membrane stability decreased by without application of nitrogen fertilizer in drought stress condition (Saneoka et al., 2004). Ouattar et al., (1997) reported yield reduction in corn by drought stress due to decrease grain weight by lessen during grain filling. Tollenaar and Lee (2002) believed that the most drought stress effect on during grain filling was on grain weight that grain weight decreased by drought stress. Plants light absorption decreased by leaf area reduction due to drought stress (Ghosh et al., 2004). This research carried out to study the effect of animal manure and superabsorbent polymer on leaf relative water content, cell membrane stability and leaf chlorophyll content of corn under drought stress condition.