不同基因型玉米间作的群体质量

采用大田试验,研究了不同基因型玉米间作的群体质量特征.结果表明,HF9‖XD20间作,植株中部叶片平均叶龄延长,而对下部和上部叶片影响不大;ZD958‖LD981间作,ZD958植株下部叶片平均叶龄延长,而中、上部叶片则缩短,LD981植株下、中、上部叶片平均叶龄均有所延长.吐丝前,群体叶面积指数(LAI)单间作无明显差异,吐丝后,HF9和LD981的LAI分别大于和显著大于单作群体,而ZD958和XD20则分别小于和显著小于单作群体.紧凑型品种和半紧凑型品种间作增加了群体透光率,吐丝后10d,4个品种棒三叶叶色值(SPADR)均有所增加,并且除ZD958外,其余3个品种棒三叶净光合速率均有所增加,其中LD981增加显著.间作对吐丝以前的群体干物质积累量影响不大,吐丝后,半紧凑型品种(HF9和LD981)的干物质积累量增加,其中LD981增加显著,而紧凑型品种(XD20和ZD958)的干物质积累量减少,其中ZD958显著减少;间作还提高了收获指数,并且两种间作群体的土地当量比(LER)均大于1.结果提示,紧凑型与半紧凑型玉米品种的间作可以提高群体质量,延长叶片功能期,提高光合效率,增加籽粒产量.

Population quality of different Maize (Zea mays L.) genotypes intercropped

A field experiment on population quality of different maize (Zea mays L.) genotypes intercropped was conducted on the farm of Henan Agricultural University, Zhengzhou, China. The results showed that, compared with that in sole|cropping treatment, mean leaf age of the middle leaves of HF9 and XD20 was lengthened in treatment of HF9 intercropping with XD20, while mean leaf age of the upper and lower leaves changed insignificantly. In treatment of ZD958 intercropping with LD981, mean leaf age of LD981 and that of the lower leaves of ZD958 were lengthened while that of middle and upper leaves shortened. No significant difference was observed in leaf area index (LAI) before silking between sole|cropping and intercropping treatments. However, after silking, LAI of HF9 increased while that of XD20 decreased significantly. LAI of LD981 increased significantly while that of ZD958 decreased slightly. Population transmittance of maize was increased when compact|plant|type hybrids intercropped with semi|compact|plant|type hybrids. Soil and plant analyzer development readings (SPADR) of the three|ear|leaves 10 days after silking of the four maize hybrids were increased in intercropping treatments. Net photosynthetic rate (Pn) for all the four hybrids except ZD958, in particular, increase in Pn of LD981 was significant. Dry matter accumulation (DMA) before silking in intercropping treatments changed slightly. After silking, DMA of semi|compact|plant|type hybrids, HF9 and LD981, was increased while that of compact|plant|type hybrids, XD20 and ZD958, was decreased. Among them, increase in LD981 and decrease in ZD958 was significant. Meanwhile, harvest index and land equivalent ratio were enhanced in intercropping treatments. The results from this study suggested that quality of maize population was improved, leaf life span was lengthened, and leaf photosynthetic efficiency and grain yield were increased when compact|plant|type hybrids intercropping with semi|compact|plant|type hybrids.