不同木薯品种留叶数处理的叶绿素荧光和产量差异OACSCDCSTPCD

Using compact varieties SC205,GR4 and umbrella varieties SC12,SC15 as the experimental materials,five treatments of 9,36,63,90 leaves remained and no leaves removed were designed to study the differences of chlorophyll fluorescence and fresh tuber root yield to clarify the differences of chlorophyll fluorescence of functional leaves in dif-ferent growth stages and leaves remained treatments and the effects of leaves number on fresh tuber root yield.The re-sults showed that with the increase of leaves,the fresh tuber root yield increased,and the tuber root number,the fresh weight of stems and leaves and the harvest index increased first and then decreased.The average of tuber root yield per plant of 9,36,63,90 and no leaf removed treatments was 0.94 kg,2.22 kg,2.65 kg,2.91 kg and 3.35 kg,respectively.The maximum fluorescence yield(Fm)and maximum quantum yield(Fv/Fm)of compact varieties were higher than those of umbrella varieties.Fm and Fv/Fm of compact varieties was 0.885 and 0.739,respectively,and those of umbrella varie-ties was 0.838 and 0.707,respectively.The minimum fluorescence yield(F0)of compact type was smaller than that of umbrella type,and that for the two plant type varieties was 0.219 and 0.231,respectively.F0,Fm,Fv/Fm,ETR and Y(II)decreased with the progress of leaf removed.With the increase of PAR,ETR increased gradually,and Y(II)decreased sharply first and then slowly.The variation trend of chlorophyll fluorescence of cassava varieties with different plant types was the same,but the variation rule of different leaves was different.The ETR and Y(II)of cassava functional leaves increased slightly when the number of leaves remained was small.