新麦草饲草产量相关农艺性状的关联性分析

Correlation Analysis of Agronomic Traits Related to Forage Yield of Psathyrostachys juncea

为了解新麦草饲草产量与农艺性状的关系,以30个新麦草种质为材料,进行相关分析、回归分析、通径分析,结果表明:新麦草种质多数农艺性状间存在较大变异;相关分析表明,单株地上生物量与株高、生殖枝数和营养枝数呈极显著正相关,与基丛径、叶层高度显著正相关;通过逐步回归分析得到回归方程Y=-483.662+3.515X1+3.103X2+1.190X7(R2=0.6554,P<0.01),表明株高(X1)、基丛径(X2)和营养枝数(X7)对新麦草地上生物量的贡献最大;主成分分析表明,基丛径、叶长、叶宽、营养枝数、株高这5个指标对新麦草地上生物量的累积贡献率达86.48%。通径分析结果表明,对单株地上生物量的直接通径系数为株高>基丛径>叶宽>生殖枝数>营养枝数>叶长>叶层高>干鲜比>再生高度。

Russian wildrye(Psathyrostachys juncea)is a perennial grass species with strong drought and winter tolerance,which could be cultivated in arid and cold area in north China.In order to understand the relationship between forage yield and agronomic traits of P.juncea,30 P.juncea accessions were used as materials for correlation analysis,regression analysis and path analysis.The results showed that most agronomic traits were quite varied among the 30 accessions.The correlation analysis showed that the aboveground biomass of a single plant had a significant positive correlation with the plant height,the number of reproductive tillers and the number of vegetative tillers,and a significant positive correlation with the diameter of the basal plexus and the height of the leaf layer.Stepwise regression analysis showed the regression equation was Y=-483.662+3.515X 1+3.103X 2+1.190X 7,which indicated that the plant height,basal perimeter and the number of vegetative tillers contributed the most to the biomass of P.juncea.Principal component analysis showed that the cumulative contribution rate to biomass of the five indicators were 86.48%,including basal diameter,leaf length,leaf width,number of reproductive tillers and plant height.Path analysis showed that the direct path coefficient for aboveground biomass(Y)of single plant was plant height>basal diameter>leaf width>number of reproductive tillers>number of vegetative tillers>leaves length>leaf layer height>dry fresh ratio>regeneration height.