植物耐低氮是受多种因素影响的数量性状,在不同的调查中,不同的参数被用于耐逆性植物的筛选。但是在使用这些指标方面没有达成一致。因此,迫切需要一种能够整合不同参数来评估应力耐受性的方法。
6个玉米基因型遭受低氮胁迫20天。然后对6个与氮相关的玉米基因型的17个性状进行了调查。将氮耐性系数(NTC)计算为低氮性状到高氮性状。然后基于NTC进行主成分分析。基于模糊数学理论,引入D值(十进制综合评价值)评价玉米对低氮的耐受性。
在低氮条件下,具有较高D值的三种玉米(SY998、GEMS42-I和GEMS42-II)具有较好的生长和较高的氮积累。相比之下,D值最低的Ji846具有最低的氮积累量和响应氮限制的生物量。这些结果表明,D值有助于筛选耐低氮玉米,考虑到D值与玉米幼苗的低氮耐受性呈正相关。
本研究引入了D值以评估应力耐受性。D值越高,玉米对低氮胁迫的耐受性更强。该方法可以降低所研究性状的复杂性,并提高胁迫耐受性评估的准确性。此外,这种方法不仅可以快速筛选出耐低氮的潜在耐性种质,但也可以包含尽可能多的相关性状,以避免单一参数的片面性。
Plants tolerant to low nitrogen are a quantitative trait affected by many factors, and the different parameters were used for stress-tolerant plant screening in different investigations. But there is no agreement on the use of these indicators. Therefore, a method that can integrate different parameters to evaluate stress tolerance is urgently needed.
Six maize genotypes were subject to low nitrogen stress for twenty days. Then seventeen traits of the six maize genotypes related to nitrogen were investigated. Nitrogen tolerance coefficient (NTC) was calculated as low nitrogen traits to high nitrogen traits. Then principal component analysis was conducted based on the NTC. Based on fuzzy mathematics theory, a D value (decimal comprehensive evaluation value) was introduced to evaluate maize tolerant to low nitrogen.
Three maize (SY998, GEMS42-I and GEMS42-II) with the higher D value have better growth and higher nitrogen accumulation under low nitrogen conditions. In contrast, Ji846 with the lowest D value has the lowest nitrogen accumulation and biomass in response to nitrogen limitation. These results indicated that the D value could help to screen low nitrogen tolerant maize, given that the D value was positively correlated with low nitrogen tolerance in maize seedlings.
The present study introduced the D value to evaluate stress tolerance. The higher the D value, the greater tolerance of maize to low nitrogen stress. This method may reduce the complexity of the investigated traits and enhance the accuracy of stress-tolerant evaluation. In addition, this method not only can screen potentially tolerant germplasm for low-nitrogen tolerance quickly, but also can comprise the correlated traits as many as possible to avoid the one-sidedness of a single parameter.