孕穗期水分灌溉处理对香稻香气及生理特性的影响

Effects of different irrigation modes on aroma content of aromatic rice at booting stage

以常规香稻品种桂香占和美香占为材料,采用盆栽试验,研究了孕穗期水分对香稻香气及生理特性的影响。结果表明:孕穗期土壤水势维持在0～-25(±5)kPa时显著增加了2个香稻品种糙米的香气含量,并在一定程度上显著提高了游离脯氨酸含量和成熟期叶片、籽粒的脯氨酸氧化酶活性。孕穗期土壤水势维持在0～-50(±5)kPa时减少了2个品种糙米的香气含量,同时降低了2个品种籽粒脯氨酸氧化酶活性,但没有达到显著水平。因此,适当的孕穗期节水灌溉模式能有效提高香稻香气含量;而较强的水分胁迫影响了水稻后期的生理活性,减少了香稻2-AP的合成与积累。两个水分处理均显著降低齐穗期倒二叶相对含水量。

Effects of different irrigation modes on aroma content and physiological characteristics in brown rice were studied in pot, by using Guixiangzhan and Meixiangzhan of the conventional aromatic rice for material at booting stage. The results showed that the sol water potential maintained at 0-25 （±5））kPa could significantly increase free proline content to a certain extent and proline oxidase activit~ of rice leaves and grains which could further significantly increase the aroma content of brown rice in both varieties. The soil watel potential maintained at 0-50 （±5）kPa could reduce proline oxidase activity of grains, but not significant, and reduced the aroma content o brown rice. Therefore, appropriate water saving irrigation could effectively improve the aroma content of aromatic rice at booting stage while, high-intensity water stress could affect the physiological activity, and reduced the formation and accumulation of 2-acetyl-1- pyrroline in the later growth process. Two irrigation modes significantly reduced the second leaf relative water content in full heading stage.