稻米品质性状对开放式空气二氧化碳浓度增高的响应

利用开放式空气CO2浓度增高(FACE)系统平台。研究大田栽培条件下粳稻武香粳14号稻米品质性状对CO2浓度增高200μmol·mol^-1的响应。结果表明．FACE处理稻谷的出糙率平均比CK高1．4个百分点，整精米率平均比CK低12．3个百分点，较低的供N水平有利于提高FACE条件下的出糙率．较高的供N水平有利于提高FACE条件下的整精米率；FACE处理的稻米垩白略有增加。垩白粒率平均比CK高11．9个百分点，垩白度平均比CK平均高2．8个百分点，较高的供N和供P水平有利于降低FACE条件下垩白大小、垩白粒率和垩白度；FACE处理稻米糊化温度平均比CK平均高0．52℃，胶稠度有提高的趋势，但对稻米直链淀粉含量影响较小，较高的供N和供P水平有利于降低FACE条件下稻米的直链淀粉含量，较低的供N和较高的供P水平有利于降低FACE条件下稻米胶稠度，较低的供N水平有利于降低FACE条件下稻米糊化温度；FACE处理使稻米蛋白质含量比CK平均低0．6个百分点，较低的供N和供P水平有利于降低FACE条件下稻米蛋白质含量。

Response of rice grain quality traits to free-air CO2 enrichment

The study showed that under field condition, when the CO2 concentration was elevated 200 micromol x mol(-1) above control, the average brown rice rate of japonica variety Wuxiangjing 14 was 1.4% higher, while lead milled rice rate was 12.3% lower than control. The brown rice rate increased at lower nitrogen supply level (LN), while lead milled rice rate increased at higher nitrogen supply level (HN). The percentage of chalky grain was 11.9% higher, and chalkiness degree was 2.8% higher than control, but no obvious difference was found in chalkiness area between the FACE and the control. The chalkiness area, percentage of chalky grain and chalkiness degree decreased at HN plus higher phosphorus supply level (HP). The gelatinization temperature was elevated 0.52 degrees C, gel consistency increased, while amylose content was not statistically significant. The amylose content decreased at HN plus HP, while gel consistency and gelatinization temperature decreased at LN plus HP and at LN, respectively. The protein content was decreased 0.6% under FACE treatment and at LN plus lower phosphorus supply level.