Effect Of Foliage Dressing Sodium Selenite At Full Heading Stage On Aroma, Selenium Content And Grain Yield Of Aromatic Rice

In this paper, the effect of foliage dressing Sodium Selenite(Na2Se O3) at full heading stage on aroma2-acetyl-1-pyrroline(2-AP), selenium content 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 ‘Nongxiang18’, using seven selenium levels by Na2 Se O3 Se0: 0mg/kg, Se1: 0.5 mg/kg, Se2: 2 mg/kg, Se3: 5mg/kg, Se4: 10mg/kg, Se5: 20mg/kg, Se6: 30 mg/kg. The effects of different selenium levels on 2-AP content, characteristic of related typical products of 2-AP synthesis, selenium content, grain yield and quality of aromatic rice were evaluated. The results are as follows:Spraying appropriate concentration Na2 Se O3 in the full heading stage can improve the content of aroma 2-AP in aromatic rice effectively. The content of aroma 2-AP in late rice cultivar Meixiangzhan, late/early cultivar Nongxiang18 tended the peak in Se2 and reached 38.07ng/g, 7.52ng/g, 21.17ng/g respectively, which 99.00%, 100.78%, 59.94% proportionally higher than the content in Se0. However, differences are shown in the early ricecultivar Meixiangzhan, that 2-AP content peak at Se4 with 27.93ng/g, 24.83% higher than that at Se0 level. 2-AP content at Se3 level is significantly higherthan Se0 as well. This is mainly related with that the appropriate selenium treatment which increase the 2-AP content in stem-sheath, leaves, and grains and maintain relatively high proline content, proline dehydrogenase activity, pyrroline-5-carboxylic acid synthetase activity,diamine oxidase activity, and ornithine aminotransferase activity in them.The Se content of brown rice tended to increase according to the growing of spraying Se concentration. There is a significant increase in most of the brown rice,except for the Se1 treatment of late rice cultivar Meixiangzhan and early rice cultivar Nongxiang18. This is mainly related with that spraying Se can improve the Se content in the leaves and grain.Yield and its component factors performance are as follows:Theactual yield of late rice cultivar Meixiangzhan in Se1 was higher than that in Se0. This is related with that Se1 treatment significantly enhancedthe seed-setting and kept the 1000-grain-weight in a higher level. The actual yield of late rice cultivar Nongxing18 in Se1 was highest, followed by Se2, which 1000-grain-weight was significantly higher than others, but the differences of them are not significant. The actual yield of early rice cultivar Meixiangzhan in Se1 was higher than others. This is mainly related with that Se1 treatmentsignificantlyenhanced the seed-setting and the 1000-grain-weight. The actual yield of early rice cultivar Nongxiang18 in Se2 was higher than others. This is mainly related with that Se2 treatment kept the seed-setting, the1000-grain-weight and the grains per paniclein a higher level.Under the experiment condition, taking into account of the aroma, selenium content and grain yield, the suitable Na2 Se O3 concentration of foliage dressing at full heading stage was 2mg/kg for late cultivar Meixiangzhan and late/early cultivar Nongxiang18 and 10mg/kg for early cultivar Meixiangzhan.