冷型小麦氮素吸收积累特性的研究

2002至2004年,通过田间小区试验,研究了4种施肥条件下(不施肥、单施磷肥、单施氮肥和氮磷配施)冠层温度持续偏低的冷型小麦氮素吸收积累特性。供试小麦品种为小偃6号、陕229、NR9405和9430,前两者为冷型小麦品种,后两者为暖型小麦品种。结果表明,花前冷型小麦叶片具有较高的氮素积累量;花后氮素吸收积累量在单施磷肥、单施氮肥和氮磷配施条件下比暖型小麦分别高168.6%、144.6%和217.4%。成熟期冷型小麦子粒中氮素积累量大,功能叶片中氮素残留量多。冷型小麦叶片较高的氮素含量为维持叶片较高的光合速率奠定了良好的氮营养基础;花后氮素吸收积累量较多的特点,与冷型小麦灌浆结实期具有较高的代谢生理活性,根系吸收氮能力强有密切关系。

Studies on nitrogen uptake and accumulation of cold type wheat

Previous studies indicated that the canopy temperature of different wheat genotypes after anthesis was different.There were many reports about the physiological,anatomic and ecological characteristics of different wheat genotypes with lower and higher canopy temperature,but little about their nutritional traits.The objective of this study was to investigate the N uptake and accumulation characteristics of genotypes with lower canopy temperature.Field experiments were conducted from 2002 to 2004 at the Agricultural Experimental Station of Northwest AF University,Yangling,Shaanxi province,China.It is a sub-humid area susceptible to drought.The genotypes Xiaoyan 6(XY6) and Shaan 229(S229) were named cold type wheat(CTW) due to their lower canopy temperature and NR9405 and 9430 were named warm type wheat(WTW) due to their high canopy temperature.For each genotype,four fertilizer treatments were setup: CK(no fertilizer),P fertilization(P2O5 176.25 kg/ha),N fertilization(N 237.0 kg/ha),and NP fertilization(P2O5 176.25 kg/ha and N 237.0 kg/ha).The treatments(variety × fertilizer) were factorial arranged with a 4×4 randomized complete block design.Each treatment was replicated three times.The area of each plot was 2.1 m2. The soil is classified as Eum-Orthic Anthrosol,equivalent to an Udic Haplustalf in the USDA system.The soil had the following chemical properties: OM,9.564 g/kg;total-N,1.08g/kg;available N,17.50 mg/kg;available P,12.27 mg/kg;and available K2O,141.24 mg/kg.The results showed that CTW had a higher N accumulation rate in foliage before anthesis.Under the condition of single application P,single application N and NP combine,N accumulation rate of CTW after flowering were 168.6%,144.6% and 217.4% higher than that of WTW,respectively.N accumulate rate in grain and N residue in the functional leaf of CTW were also higher at maturity stage.The high N content in leaves of CTW established a good N nutritional foundation for maintaining a high photosynthesis rate.The high N accumulation rate after anthesis of CTW was close related to their high metabolic physiological activities at grain filling stage and their strong root N uptake capacity.