硒肥对香稻香气和糙米硒含量以及产量的影响

为了探明齐穗期喷施亚硒酸钠(Na_2SeO_3)对香稻香气、糙米硒含量和产量的影响,为富硒香稻栽培提供理论依据。设置了4个Na_2SeO_3浓度水平,依次为0(Se0),10(Se1),20(Se2),30 mg/kg(Se3),以常规香稻品种美香占和农香18为试材进行盆栽试验,研究了不同硒肥水平对糙米香气含量、茎鞘香气含量、叶片香气含量、籽粒香气含量、糙米硒含量和产量及其构成因素的影响。结果表明:2个供试品种在Se1、Se2水平下,其糙米香气2-AP含量维持在较高水平,这主要得益于在Se1、Se2普遍提高了香稻茎鞘、籽粒以及叶片齐穗后7 d和齐穗后14 d的香气含量。其中晚季美香占Se2显著提高了糙米香气含量,达到了35.73 ng/g,比Se0提高了85.03%,晚季农香18的Se2糙米香气最高,但差异未达到显著水平,早季美香占Se1的糙米香气含量显著高于其他处理,早季农香18的Se1、Se2、Se3糙米香气显著高于Se0。齐穗期喷施Na_2SeO_3能显著提高糙米硒含量。早季农香18的Se3实际产量显著低于其他处理,原因在于较高的硒浓度降低了结实率和千粒质量。齐穗期喷施适当浓度的亚硒酸钠,结实率可以得到提高或保持。在本试验条件下,兼顾2种香稻品种对硒肥的反应,齐穗期喷施Na2SeO_3最适宜浓度为10~20 mg/kg。

Effect of Selenium Fertilizer on Aroma,Selenium Content in Brown Rice and Grain Yield of Aromatic Rice

The effect of foliage dressing Sodium Selenite(Na2SeO3) at full heading stage on aroma,selenium content in brown rice and grain yield of aromatic rice were investigated to provide theoretical basis for suitable selenium fertilizer application rate in aromatic rice production.Pot experiments were conducted with two conventional aromatic rice cultivars Meixiangzhan and Nongxiang 18,using four selenium levels by Na2SeO3 0 (Se0),10 (Se1),20 (Se2),30 mg/kg (Se3),the effects of different selenium levels on 2-Acetyl-1-Pyrroline (2-AP) content in brown rice,2-AP content in stem-sheath,2-AP content in leaves,2-AP content in grains,selenium content in brown rice,grain yield were evaluated.The result showed that the treatments Se1,Se2 were conducive to higher levels of 2-AP in brown rice,as Se1,Se2 improved 2-AP accumulation in stem-sheath,grains and leaves at 7 d after heading stage and 14 d after full heading stage.Compared with Se0,Se2 improved the 2-AP content in brown rice significantly for Meixiangzhan of late rice,with an increased of 85.03％,up to 35.73 ng/g.Se2 achieved the highest 2-AP content in brown rice for Nongxiang 18 of late rice,but the difference was not significant.For Meixiangzhan of early rice,the 2-AP content in brown rice of Se1 was significantly higher than other treatments.Compare with Se0 treatment,Se1,Se2,Se3 for Nongxiang 18 of early rice improved the 2-AP content in brown rice significantly.Foliage dressing Na2SeO3 at full heading stage had a significant increase on selenium content in brown rice.Foliage dressing Na2SeO3 at full heading stage harvested the same level of grain yield as Se0,except that compared with Se0,grain yield of Se3 for Nongxiang 18 of early rice had a significantly decrease.This is maybe due to that Se3 treatment keptthe 1 000-grain-weight in a lower level,and other treatments kept the 1000-grain-weight and seed-setting in higher level.Under the experiment condition,taking into account of the reactions of two aromatic rice cultivars for selenium fertilizer,the suitable Na2SeO3 concentration of foliage dressing at full heading stage was 10-20 mg/kg.