不同氮素形态对蒙古栎幼苗生长及生理特性的影响

Effects of Different Nitrate Form on the Growth and Physiological Characteristics for Quercus mongolica Seedlings

为揭示不同氮素形态对蒙古栎幼苗生长与生理的影响,以1年生蒙古栎幼苗为试验材料,采用温室栽培方法,测定不同硝铵配比处理下蒙古栎幼苗生物量、光合作用、叶绿素含量以及可溶性蛋白含量。结果表明:增加铵态氮的比例能够显著提高幼苗生物量、光合作用、叶绿素含量以及可溶性蛋白含量;不同硝铵比对蒙古栎幼苗生物量影响差异显著,NO-3-N与NH+4-N摩尔比为2∶6处理下全株生物量最大,分别是纯硝和纯铵处理的1.27倍和1.34倍,但与NO-3-N与NH+4-N摩尔比为4∶4处理下生物量差异不显著;幼苗光合速率和蒸腾速率在NO-3-N与NH+4-N摩尔比为4∶4处理下达最大;光合速率分别是纯硝和纯铵的2.65倍和1.88倍,蒸腾速率分别是纯硝和纯铵的3.11倍和2.13倍;叶绿素a、类胡萝卜素以及可溶性蛋白含量均在4∶4处理下最高。以上结果表明,铵态氮与硝态氮等量混合更能促进蒙古栎幼苗的生长。

To reveal the effects of different nitrogen forms on growth and physiology of Quercus mongolica,the biomass,photosynthesis,chlorophyll and soluble protein contents were measured in annual seedlings by cultivating in green house.The results showed that increasing the proportion of ammonium nitrogen could significantly increase the seedling biomass,photosynthesis,chlorophyll contents and soluble protein contents.The effect of different nitrogen forms ratios on the biomass was significantly different.The whole plant biomass was the highest when the ratio of NO-3-N/NH+4-N was 2∶6.The biomass was 1.27 and 1.34 times respectively that the pure nitrate and the pure ammonium.But the difference was not significant between NO-3-N/NH+4-N of 4∶4.The photosynthetic rate(Pn)and transpiration rate(Tr)reached the maximum when the ratio of NO-3-N/NH+4-N was 4∶4.The Pn was 2.65 and 1.88 times of pure nitrate and pure ammonium.The Tr was 3.11 and 2.13 times of pure nitrate and pure ammonium.The contents of chlorophyll a,carotenoid and soluble protein appeared highest at NO-3-N/NH+4-N ratio of 4∶4.These results suggested that the equal mixing of ammonium and nitrate can promote the growth of Quercus mongolica seedlings.