【作者】 张治安；

【导师】 徐克章；

【作者基本信息】 吉林农业大学 ， 作物栽培学与耕作学， 2007， 博士

【摘要】 在大豆品种遗传改良过程中，选育的高产大豆品种已整合了多项高产的结构和功能特征。有些形态结构特征是显而易见的，但许多功能特征，特别是生理特性则是在选择过程中易被忽视的。本项研究旨在利用现代测试分析技术，对在常规育种中易被忽视的大豆叶片净光合速率、气孔导度、蒸腾速率等指标进行测定与分析，期望为高产育种提供理论依据。试验于2005～2006年在吉林农业大学试验田进行，结果如下：1)产量是大豆育种的一个重要指标。吉林省栽培大豆品种遗传改良中，大豆产量从1923年—2005年的82年间增加了1103.7 kg·hm^-2，平均每年增加13.46 kg·hm^-2，增加的百分率为95.94％，每年增长1.17％。2)随着大豆品种的遗传改良，叶面积指数不断增加。开花期以后叶面积指数与产量呈极显著正相关。1920s-1940s、1950s-1960s、1970s-1980s和1990s-2000s四个年代大豆品种的叶面积指数动态均呈抛物线状态，最大叶面积指数时期均出现在出苗后70天左右，1990s-2000s品种的叶面积指数分别比1920s-1940s、1950s-1960s、1970s-1980s品种的叶面积指数平均高出15.8％、12.0％和8.6％。说明，新品种的叶面积指数比老品种增加快且指数最大值较大，鼓粒期最大叶面积指数稳定期较长，衰退缓慢。这是大豆品种遗传改良中籽粒产量提高的主要原因之一。3)在大豆品种遗传改良中，收获指数随品种育成年代和产量的增加而增加。收获指数与产量呈极显著正相关。对干物质积累变化的研究表明，在整个生育期内，不同年代育成的大豆品种植株干物重和籽粒干物质积累均随年代的推进呈线性增加。不同年代大豆品种的植株干物重从出苗到鼓粒盛期（出苗后90天）逐渐增加，到鼓粒盛期达最大值，然后有所下降；大豆籽粒干物质积累从鼓粒初期（出苗后80天）到鼓粒末期（出苗后110天）逐渐增加，到鼓粒末期达最大值，成熟期略有下降。从鼓粒初期到成熟初期的40 d里，1920s-1940s、1950s-1960s、1970s-1980s和1990s-2000s品种的籽粒干重增长速率分别为4.86、5.95、7.09和8.08 g·m^-2·d^-1。现代品种籽粒增重速度快可能是品种产量提高的主要原因之一。4)对五个生育期间大豆叶片净光合速率与品种育成年代的相关分析表明，大豆结荚期叶片净光合速率与品种育成年代呈极显著的正相关，且相关系数最高(r=0.7275^**)。通过对五个生育期间各个参数的比较和分析发现结荚期是大豆发育的重要时期，它直接决定着光合有效产物的运转和分配，在整个生育期内，大豆的净光合速率的最高值在结荚期，特别是高产的1990s-2000s大豆品种，结荚期的净光合速率要比1920s-1940s大豆品种高25.7％。结荚期是影响大豆产量的关键时期。5)对大豆的净光合速率和表观叶肉导度（Pn／Ci）与产量的相关分析表明，在整个生育期内，净光合速率和Pn／Ci与产量皆存在显著或极显著的正相关关系，在苗期的相关系数最小（r=0.4309^*、0.4816^*），结荚期的相关系数最大(r=0.6368^**、0.6502^**)。净光合速率和Pn／Ci可作为高产育种的生理选择指标。6)在大豆品种遗传改良中，净光合速率，气孔导度、蒸腾速率、叶绿素含量和比叶重也随品种育成年代推进有不同程度的增加。现代高产品种并不是只具有高的净光合速率，气孔导度、蒸腾速率、叶绿素含量和比叶重等其它与产量形成密切相关的参数也较高，但在这些指标中净光合速率与产量的关系最为密切和稳定。所以，气孔导度、蒸腾速率、叶绿素含量和比叶重可作为品种选择的辅助指标。7)瞬时水分利用效率在大豆开花期随品种育成年代推进而降低的变化，到成熟期则随品种育成年代推进而增加。原因是现代品种花期叶片净光合速率提高的同时，蒸腾速率提高得更多。而成熟期老品种水分利用效率降低是由于净光合速率降低更快所致。8)叶片胞间CO₂浓度与品种育成年代呈负相关变化。并表现为净光合速率较高的时候，胞间CO₂浓度却较低，而这时气孔导度并不低。这说明随着大豆品种更替当代品种叶片同化CO₂的能力增强。同时也暗示新品种叶片Pn进一步提高可能存在气孔限制。9)在大豆发育的关键时期结荚期，叶片净光合速率、气孔导度的日变化呈双峰曲线变化，峰值出现在上午10：00和下午15：00。蒸腾速率呈单峰曲线变化，峰值出现在中午12：00。在整个日变化中，四个年代大豆品种的净光合速率、气孔导度和蒸腾速率的大小顺序为1990s-2000s品种＞1970s-1980s品种＞1950s-1960s品种＞1920s-1940s品种。10)大豆鼓粒末期以后，1990s-2000s的品种仍能保持比1920s-1940s、1950s-1960s、和1970s-1980s品种相对较高的PSⅡ最大光化学效率（Fv／Fm）和光系统Ⅱ实际光化学效率(φ_PSⅡ)。说明，现代品种叶片比老品种衰老缓慢，从而能使光合作用过程顺利进行，为碳同化提供更充足的能量和还原能力。11)不同生育时期大豆叶片的硝酸还原酶活性差异较大，硝酸还原酶活性大小为R₂期＞V₄期＞R₄期＞R₆期。同一生育时期不同品种叶片硝酸还原酶活性也有一定差异，在V₄期、R₂期、R₄期和R₆期的变异系数分别为17.6％、8.6％、8.5％和12.7％，存在极显著或显著差异。12)大豆品种各生育时期的硝酸还原酶活性均随年代的推进呈线性增长变化，并与育成年代呈显著正相关，相关程度各生育时期大小排序为：V₄期＞R₂期＞R₆期＞R₄期。13)在大豆品种遗传改良中，叶片硝酸还原酶活性的提高与产量的增长关系密切。所以，叶片硝酸还原酶活性也可作为大豆高产品种选择的指标之一。更多还原

【Abstract】 With the genetic improvement in soybean cultivars, selective breeding high production soybeancultivars conformed high-yield structure and function characteristic. Some structure characteristic is choiceresult, but some concealed physiological characteristic hasn’t been noted in the choice process. As theimprovement of modern technology, some concealed physiological characteristic may measure using theinstrument surveys definitely. Using modern test analysis technology, we measured and analyzed the netphotosynthetic rate （Pn）, stomata conductance （Gs）, transpiration （Tr） in the leaves. The expectationprovides the theory basis for the high yield breeding.From 2005 to 2006, the experiment was conducted at experimental station of Jilin AgriculturalUniversity, the results as follows:Yield is a important index of soybean breeding. With the genetic improvement in soybean in Jilinprovince, the yield has increased 1103.7 kg/hm² in the past 82 years from1923—2005, increased 95.94%, or12.5 Kg/hm² year and 0.98% in each year.Leaf area index （LAI） was increased as the genetic improvement of soybean cultivar. LAI was highlysignificantly positive correlated with yield after flowering stage. LAI was parabola condition, which ofsoybean cultivar in 1920s-1940s, 1950s-1960s, 1970s-1980s, 1990s-2000s .There was the largest leaf areaindex at about 70 days after seedling. The LAI of 1990s-2000s breed were higher 15.8%, 12.0% and 8.6%than that of 1920s-1940s, 1950s-1960s, and 1970s-1980s, respectively. The result showed that the LAI ofnew breed rapidly increased, highly maximum, longer and calm the largest LAI, slow wither comparedwith the old breed. It is a main reason of seed yield increasing as the genetic improvement of soybeancultivar.As the increase of yield, harvest index was increase with year of release during the geneticimprovement in soybean cultivars. Harvest index was highly significantly positive correlated with yield.The variation of dry matter accumulation showed that the plant dry matter weight and grain seed dry weightof breeding in different years were increased with the year of release. The plant dry matter weight wasincreased gradually from seedling to middle seed-filling stage （after seedling 90 days）. The maximum is atthe middle seed-filling stage, then decline. Dry matter accumulation was increased gradually from beginseed-filling （after seedling 80 days） to end seed-filling stage （after seedling 110 days）, the maximum was atthe end seed-filling stage, decline at mature stage. During 40 days from begin seed-filling to endseed-filling stage, the increasing rate of seed dry weight is 4.86,5.95,7.09 and 8.08 g·m^-2.d^-1 in soybean cultivar in 1920s-1940s, 1950s-1960s ,1970s-1980s, respectively. It is one of the important factors ofincreased grain yield, that seed dry weight is rise quick in modern soybean cultivars.The correlation analysis of leaf photosynthetic rate and the breeding year during the five growth stagesshowed that: the leaf photosynthetic rate was highly significantly positive correlation at the seed-poddingstage, and the related coefficient is the highest (r=0.7275^**). Through to five growth stages each parametercomparison and the analysis, we discovered that seed-podding stage is important time of soybean growth. Itwas deciding directly the photosynthesis effective product revolution and assign. At the whole stages,seed-podding stage has the highest net photosynthetic rate, especially the photosynthetic rate of high yieldcultivar breeding after the 1990s-2000s were higher 25.7% than the cultivar of 1920s-1940s at theseed-podding stage. The seed-podding stage is crucial stage that affects the soybean yield.The correlation analysis of leaf photosynthetic rate, Pn/Ci and yield showed that: At the whole growthstages, the leaf net photosynthetic rate, Pn/Ci was highly significantly or significantly positive correlationwith yield. The related coefficient（r=0.4309^*、0.4816^*） is the highest in seedling, and the relatedcoefficient(r=0.6368^**, 0.6502^**) is the highest in seed-podding stage. Pn and Pn/Ci could as physiologicalselection indexes of high yield breed.During the genetic improvement in soybean cultivars, Pn, Gs, Tr, chlorophyll content and SLW isincreasing with year of release. Pn of modern high yield cultivars wasn’t only high, but Gs, Tr, chlorophyllcontent and SLW of the close correlation parameter with the yield forms also high. The yield and Pn hadthe most close and stable relationship in all of index. Therefore, Gs, Tr, chlorophyll content and SLW couldas auxiliary selection indexes of high yield breed.Water usage efficiency （WUE） was decreased with year of release in flowering stage, but it wasincreased with year of release in maturity stage. The reason was that the increase of Tr was greater than theincrease of Pn of modern cultivars with year of release in flowering stage. WUE of old cultivars wasdecreased in maturity stage, it is the reason that Pn was reduces quicker than Tr.Intercellural CO₂ concentration （Ci） was negative correlated with year of release. Ci was low, when Pnand Gs were high. This indicated that present cultivars leaf assimilates CO₂ the ability strengthens with thesoybean cultivars change. Continually Pn increasing could be limited from stomata in leaves of presentcultivars.In seed-podding stage of crucial stage affects the soybean grow, the diurnal variation of Pn and Gswere the "double peek" curve, the peak value appears in the morning 10:00 and afternoon 15:00. Diurnalvariation of Tr was the "one peek" curve, the peak value appears in the 12:00. At the whole diurnalvariation, Pn, Gs ,Tr of four ages soybean cultivars order 1990s-2000s＞1970s-1980s＞1950s-1960s＞1920s-1940s.After last phase pod-filling, the maximal efficiency of PSⅡphotochemistry （Fv/Fm） and actual efficiency of PSⅡ(φ_PSⅡ) in leaves of soybean cultivars of 1990s-2000s were higher than soybean cultivarsof 1920s-1940s, 1950s-1960s, and 1970s-1980s. The result indicated that newer soybean cultivars leaveswere slower than older soybean cultivars leaves of senescence rate. Therefore high Pn in leaves newersoybean cultivars of could provide more ATP and NADPH.The nitrate reductase activity （NRA） in the leaves of soybean was different significantly at everystage. The order of NRA from high to low was: R₂ stage＞V₄ stage＞R₄stage＞R₆ stage. There weredifference in NRA in the leaves of soybean in the same growth stage ,the CV% respectively were17.6%,8.6%,8.5% and 12.7% at V₄ stage, R₂ stage, R₄stage and R₆ stage, there were very significantdifference or significant difference.The nitrate reductase activity at different growth stage was increased linearly from 1923 to 2005,andthere was significant positive relationship between NRA and the year of release, the order of relationshiplevel from high to low is : V₄ stage＞R₂ stage＞R₆ stage＞R₄ stage.Increasing of Nitrate Reductase Activity （NRA） in the leaves and yield is close in the geneticimprovement in soybean cultivars. Therefore, NRA in the leaves could be one of selection index forhigh-yield soybean cultivars.更多还原