两个黑麦草种生产性能的比较

COMPARISON ON PRODUCTIVITY BETWEEN ITALIAN RYEGRASS AND PERENNIAL RYEGRASS

用4个多花黑麦草品种和7个多年生黑麦草品种进行田间试验,分析比较了两个黑麦草种的生长速率(CGR)、叶面积指数(LAI)和净同化率(NAR)等生产性能。结果表明:黑麦草种间的出叶速度无显著差异,但多花黑麦草的叶面积扩展速度显著大于多年生黑麦草;多花黑麦草生产性能显著优于多年生黑麦草;其原因是前者生长各阶段 CGR 均显著大于后者;CGR 与 LAI 成显著正相关,黑麦草种间、品种间的生产性能优劣主要决定于 LAI 的大小;品种间 CGR 与 NAR 成显著正相关, 但 NAR 对 CGR 的影响远小于 LAI.

4 cultivars of Italian ryegrass Lolium multiflorum Lam.and 7 cultivars of perennial ryegrass L.perenne L.were used in field experiments to compare their productivity,crop growth rate(CGR),leaf areaindex(LAI)and net assimilation rate(NAR).The results showed that(1)the leaf appearance rate didnot differ significantly between two ryegrasses,but the leaf expansion rate of Italian ryegrass was significantlyhigher than that of perennial ryegrass;(2)the productivity of Italian ryegrass was significantly superior toperennial ryegrass,because the CGR of the former was higher than that of the latter;(3)CGR wassignificantly positively correlated with LAI,and the difference of productivity between the species and be-tween the cultivars mainly resulted from the difference of LAI;(4)CGR also significantly positively relatedto NAR,but the effect on CGR of NAR was less than that of LAI.