不同诱变处理对苜蓿叶绿素含量及光合作用的影响

为研究60Co-γ射线、紫外线、零磁空间和EMS诱变处理对苜蓿SP1代叶片叶绿素含量及光合作用的影响，筛选最优诱变处理梯度，选育适合高寒地区种植的苜蓿新品系或品种。以‘公农1 号’、‘Wega7F’、‘WL319HQ’、‘敖汉’4 个苜蓿品种试验材料，设置60Co-γ射线150、300、450 Gy射线强度，紫外线30、60、90 min 照射时间，EMS 0.1%、0.2%、0.4%(v/v)溶液浓度，零磁空间处理180 天；测定苜蓿叶片叶绿素a、叶绿素b、叶绿素总量、叶绿素a/b 值以及净光合速率。结果表明，‘公农1 号’450 Gy60Co-γ处理、紫外线处理时间为30 min和0.4%EMS处理下叶绿素a 含量最高，均高于对照3.17 mg/g，但与对照差异不显著，其他处理均低于对照。‘Wega7F’在紫外线60 min 时间处理下，叶绿素b 值明显增加，且显著高于其他处理(P<0.05)。‘公农1 号’在450 Gy 60Co-γ辐射处理下叶绿素含量最高，a/b 比值最小，其他3 个品种在150 Gy处理下叶绿素含量最高，但a/b 比值最小。各苜蓿品种不同诱变处理净光合速率大小依次为：60 min 紫外线处理的‘Wega7F’>零磁空间处理的‘敖汉’>0.4%EMS 处理的‘WL319HQ’>0.4%EMS处理下的‘公农1 号’。150 Gy60Co-γ射线、60 min 紫外线、0.4%浓度EMS处理为苜蓿正向变异处理，有利于筛选有益诱变突变体。

Effect of Mutagenesis on Chlorophyll Content and Photosynthesis of Alfalfa

The research took‘Gongnong 1’,‘Wega7F’,‘WL319HQ’,‘Aohan’as the material and tested the effects of treatments 60Coγ- ray irradiation, ultraviolet, EMS and magnetic field- free space on chlorophyll content and photosynthesis, aiming to screen the optimal induction mutation method and breed new alfalfa varieties for alpine region. The treatments were set as 60Coγ-ray irradiation (150, 300, 450 Gy), ultraviolet (30, 60, 90 min), EMS [0.1%, 0.2%, 0.4% (v /v )] and magnetic field-free space (180 d). Chlorophyll content and net photosynthetic rate of leaf were determined. The results showed that: chlorophyll a of‘Gongnong 1’induced by 450 Gy60Coγ-ray, 30 minutes ultraviolet and 0.4 (v /v ) EMS was higher than that of CK (3.17 mg/g), but other treatments showed a reverse trend. The chlorophyll b of‘Wega7F’induced by irradiation 60 minutes was the highest (P <0.05). Value of chlorophyll a/b of‘Gongnong 1’induced by 450 Gy60Coγ-ray was higher than that of other alfalfa varieties. The net photosynthetic rate of‘Wega7F’induced by irradiation 60 minutes>‘Aohan’ induced by magnetic field-free space >‘WL319HQ’induced by 0.4% (v /v ) EMS >‘Gongnong 1’induced by 0.4% EMS (v /v ). 150 Gy60Coγ- ray irradiation, 60 min ultraviolet and 0.4% EMS were positive mutagenic treatments that were conducive to screening mutants.