盐渍化土壤水肥耦合对向日葵苗期生长影响的试验

Effects of coupling of soil water and fertilizer on the growth of sunflower during its seeding period in saline soil

采用盆栽试验定量分析方法,模拟研究了不同盐分胁迫下,水肥对向日葵苗期冠层形态特征、干物质量及其分配的影响,揭示了盐渍化土壤水肥耦合机制。结果表明:水盐胁迫使向日葵的生长发育显著受阻,苗期明显滞后、株高、茎粗及叶片数显著减少,干物质量下降;在养分供应到一定程度上有助于缓解水分胁迫对向日葵生长发育产生的影响,而且养分供应不足时水分的增产作用会受到影响。据试验结果初步确定水盐(中度含盐处理)双重胁迫条件下的水肥配合值为:灌水定额为田持的75%(中水)并配施肥300 kg/hm2(中肥)时,最大干物质量为845.1 kg/hm2。合理施肥、量水配肥是盐渍化地区节水灌溉提高作物产量的有效措施。

According to the pot experiment and by quantitative analysis, simulation of the different water and N management patters influencing the canopy physiological shape, dry matter and different distribution of sunflower seeding stage in water-salt stress was conducted. Results showed that the development of sunflower was stunted and plant height, the quantity of leaf and the amount of dry matter were obviously decreased in water-sah stress. When the nutrient supplied reached a certain extent which would release the effect on development of sunflower, then the nutrient supplied was insufficient the effect of water increasing in yield would be influenced. The coupling ＂effects of soil water and fertilizer on the interdependence of canopy physiological shape, dry matter and different distribution of sunflower were investigated, which discloses the high efficiency coupling principle of water and fertilizer. According to the result of preliminary experiment determination of water salt （moderate salt treatment） dual forces under which the water and fertilizer coordination value is： When irrigateing the fixed quantity to hold for the field 75 % （moderate water） and matching fertilizer application 300 kg/hm^2 （moderate fertilization）, the most going all out quality is 845.1 kg/hm^2. Therefore, proper fertilization is an effective method for water saving irrigation in saline area.