水保所知识产出(1956---)知识库

探寻不同覆盖措施下玉米籽粒氮素积累和物质转移的“源-库”过程。【方法】以中国西北黄
土高原典型旱作农业区春玉米生产体系为对象，通过 2 年田间试验，对覆盖地膜、覆盖砂砾和不覆盖 3 个处理的
光能捕获和土壤温度进行定位观测，分析干物质累积转移和氮素的积累，揭示地表覆盖对“源-库”过程的影响。
【结果】覆膜处理的有效积温显著高于不覆盖处理，与覆砂处理差异不显著。覆膜处理辐射生产效率显著高于覆
砂处理。覆膜处理的积温生产效率显著高于其他处理，其辐射生产效率在 2010 年与其他处理差异不显著，但在
2011 年显著高于不覆盖处理，低于覆砂处理。茎+叶鞘的干物质转移量最大，地表覆盖对转移干物质贡献率及干
物质转移率影响不显著。覆膜条件下，玉米单穗粒重及单穗粒数在收获时均高于其他处理。在吐丝后前 30 d，覆
膜处理籽粒平均含氮量明显高于覆砂和不覆盖处理；灌浆 30 d 至成熟，处理间籽粒含氮量差异较小，覆膜处理略
高于覆砂和不覆盖。由于籽粒干重差异，覆膜处理籽粒氮累积量显著高于覆砂处理和不覆盖处理。覆盖处理有效
提高了果穗上部籽粒氮素累积，其次为中部和下部籽粒；覆膜处理果穗各部分籽粒氮累积量明显高于覆砂和不覆
盖处理；干物质转移量和转移干物质贡献率均与单穗粒重和有效积温呈正相关，达到了显著水平，而与单穗粒数、
光合有效辐射捕获量、积温生产效率及辐射生产效率虽呈正相关，但未达到显著水平。覆膜通过影响单穗籽粒数
及穗粒干重而增加籽粒干物质累积能力，进而促进籽粒氮素累积，增加产量。【结论】覆膜促使源能力和库容量
的协同增加是玉米增产的根本原因。

A field study on dryland spring maize in three treatments was conducted to explore the source-sink
relationship between nitrogen accumulation and dry matter transfer in different mulching treatments on the Changwu Tableland of
the Loess Plateau in northwest China. 【Method】The light energy capture and soil temperature in treatments of plastic film mulching,
gravel mulching, and no mulching (CK) were observed, and dry matter accumulation and nitrogen accumulation were analyzed
through two years.【Result】The effective accumulated temperature of the plastic film mulching was significantly higher than that of
the CK treatment, but no significant differences compared with gravel mulching treatment. The radiation utilization efficiency of the  plastic film mulching treatment was significantly higher than that of the other treatments. The accumulated temperature production
efficiency of plastic film mulching treatment was significantly higher than that of other treatments, the difference of its radiation
production efficiency with other treatments was not obvious in 2010, and however, its radiation production efficiency was
significantly higher than that of CK treatment and lower than that of gravel mulching treatment in 2011. The dry matter transfer
amount of stem and leaf sheath reached the maximum. The contribution rate of soil surface mulching to dry matter transfer and its
impacts on dry matter transfer rate were not significant. At reproductive growth stage, the single grain weight of corn grain increased
with growth of corn. However, the number of single grain decreased instead. Under the condition of plastic film mulching, the weight
and number of single grain in harvest time were higher than that in other treatments. Within 30 days after silking, the average
nitrogen content of corn grain in plastic film mulching was significantly higher than that in gravel mulching and CK treatments;
within 30 days after grain filling and up to mature period, the difference of nitrogen content in corn grains was not significant and the
nitrogen content in plastic film mulching treatment was slightly higher than that in gravel mulching and CK treatments. As the
difference in dry weight of corn grains, the nitrogen accumulation amount in plastic film mulching was significantly higher than the
that in grave mulching and CK treatments. The mulching treatment had effectively increased the nitrogen accumulation of grains in
upper, middle and lower parts of corn ear; the nitrogen accumulation amount of grains in each parts of corn ear in plastic film
mulching treatment was significantly higher than that in gravel and CK treatments. The dry matter transfer amount and contribution
rate to dry matter transfer were positively related to the volume and weight of single grain and effective accumulated temperature,
which reached at a significant level; however, although the dry matter transfer amount and contribution rate to dry matter transfer
were positively related to the number of single grain, the fractional interception of photosynthesis active radiation and production
efficiency of accumulated temperature and radiation, it did not reach at a significant level. The plastic film mulching increased the
dry matter accumulation capacity based on the number of single grains, and dry weight of ear grain to facilitate nitrogen
accumulation of corn grains, improve the nitrogen use efficiency and increase production.【Conclusion】The plastic mulching
promoted the accumulation of nitrogen and improved the utilization efficiency of nitrogen, thus improved the yield of maize on the
Loess Plateau.