应用^(15)N稀释法筛选高固氮能力的大豆品种

USE OF ^( 15) N DILUTION METHOD FOR SCREENING SOYBEAN LINES WITH HIGH YIELD AND HIGH NITROGEN FIXATION ABILITY

应用１５Ｎ稀释法筛选出了具有高固氮能力的大豆品种和品系。大豆品系１００５、８５０２、２０９６、１４５４、９４３和东农４２是高固氮品系，它们的固氮效率高达７０％，大豆品系１４５４和１５５５既高产又高固氮。根据方差分析，不同大豆品种或品系固氮效率差异显著，固氮效率与产量无相关关系，与成熟期呈正相关，成熟期越长，固氮效率越高。有１０个品种或品系在１９９２和１９９４年两次进行试验，尽管两年的降雨情况有较大的差异，１０个品种或品系中有７个品种或品系固氮效率是一致的，说明在不同年份大多数大豆品种的固氮效率是稳定的。但是，有两个品系８５０２和２０９６，在降雨较多的１９９４年固氮效率增长了１９％，说明个别大豆品种，在不同条件下固氮效率可能改变。

N dilution method was used for screening soybean lines with high nitrogen fixation ability. Screened lines 1005,8502,2096,943,1454 and Dongnong 42 have high nitrogen fixation ability with their %Ndfa of about 70%. 1454 and 1555 are both high yield and high nitrogen fixation lines. The ability of nitrogen fixation was not related to the yield, but related to maturing time. The cultivars with different maturing time have different levels of nitrogen fixation ability. The longer the maturing period is, the greater the ability of nitrogen fixation it has. There were ten cultivars or lines used in the test of 1992 and 1994. Although the weather condtion were greatly different between the two years the results of seven cultivars or lines were the same, indicating that nitrogen fixation ability of the soybean is stable with years. Using 15 N dilution method to estimate nitrogen fixation ability of soybean is reliable, however, the %Ndfa of lines 8502 and 2096 increased by 19% in 1994, a rainy year, indicating that a change in %Ndfa with a few varieties maybe caused by weather.