二倍体与四倍体西瓜叶片若干生理指标比较

以西瓜二倍体及其人工诱导的同源四倍体为材料,研究其叶片生长过程中的光合色素含量及抗性相关生理指标的变化差异。结果表明,单位叶面积的四倍体西瓜叶绿素a、叶绿素b和总叶绿素含量均高于二倍体,且差异都达到显著水平,而类胡萝卜素含量则略低于二倍体,差异不显著;四倍体西瓜叶片的SOD、POD和PPO活性均显著高于二倍体,CAT活性高于二倍体,但差异不显著,而MDA含量则显著低于二倍体。说明四倍体西瓜的光合作用、抗逆性要优于二倍体。     

不同倍性甜瓜果实品质比较研究

为探讨不同倍性甜瓜果实品质差异,试验以2个二倍体甜瓜品种及其人工诱导的同源四倍体、三倍体为材料,对不同倍性甜瓜成熟果实可溶性糖、中心可溶性固形物、可溶性蛋白质、维生素C含量进行比较分析。结果表明,不同倍性甜瓜果实成熟时期可溶性糖、中心可溶性固形物、可溶性蛋白质、维生素C含量存在差异,可溶性糖、中心可溶性固形物和可溶性蛋白质含量有同样趋势,为三倍体＞四倍体＞二倍体;维生素C含量为四倍体＞三倍体＞二倍体。     

湖南不同产区烤烟中部叶糖和有机酸含量的差异分析

为研究湖南不同产区烤烟糖和有机酸含量的差异对烟叶香气风格形成的影响,采用气相色谱法,对湖南4个不同产区郴州、邵阳、凤凰和慈利烤烟中部叶的糖和有机酸含量进行分析。结果表明：凤凰与邵阳的总糖和还原糖含量明显高于慈利和郴州,但非挥发酸含量却恰恰相反。4个产区烟叶中非挥发酸、挥发酸和有机酸总量均以慈利最高,郴州次之,凤凰最低,但凤凰的高级脂肪酸总量最高且与其他产区之间差异极显著;除丙二酸外,其他非挥发酸含量差异均达极显著水平;异丁酸、戊酸和3-甲基戊酸含量在产区间差异极显著,而丁酸差异不显著,其他绝大多数挥发酸含量产区差异较大,但4个产区间差异没有规律;慈利、凤凰和郴州这3个产区烟叶中的高级脂肪酸含量差异不大,但邵阳与这3个产区之间除肉豆蔻酸外其他成分含量差异均达显著水平。     

架式与负载量对晚红葡萄果实品质的影响

以三年生晚红葡萄为试验材料,研究了不同架式及负载量对果实品质的影响。结果表明:立体棚架栽培的果实单粒重、可溶性固形物含量、固酸比等品质指标均高于平棚架和篱架,总酸含量低于二者;立体棚架叶片净光合速率(Pn)极显著高于棚架和篱架(P0.01),并且叶片Pn与果实单粒重、总糖含量呈显著正相关。单粒重与总糖、固酸比呈极显著正相关,与总酸呈显著负相关。总糖与固酸比呈极显著正相关。总酸与固酸比呈极显著负相关。立体棚架保留8～10个/m2新梢对其光能利用和果实品质较适宜。     

二倍体与四倍体葡萄品种形态特征与若干生理指标比较研究

为了给葡萄倍性选育工作提供理论依据和科学参考价值,对不同葡萄品种二、四倍体的形态特征、叶绿素含量、原花色素含量及POD、CAT、MDA含量进行了测定、分析。结果表明：（1）不同葡萄品种四倍体在植物学特性方面与二倍体对照,表现出巨大性的特点;（2）不同葡萄品种叶片中原花色素含量四倍体高于二倍体;（3）不同葡萄品种叶片中叶绿素含量四倍体高于二倍体;（4）不同葡萄品种叶片中MDA含量均极低;（5）不同葡萄品种叶片中POD、CAT活性四倍体高于二倍体。由此可以看出,葡萄同源四倍体相对于二倍体植株而言,不仅其形态方面均表现出巨大性的特点,同时适应性和抗逆性也均增强。     

喀什‘灰枣’‘骏枣’果实主要营养物质相关性分析

为研究喀什红枣果实主要营养物质间的相关性,以5年生喀什‘灰枣’和‘骏枣’为对象,测定成熟期果实矿质元素、总糖、总酸和维生素C含量。‘灰枣’和‘骏枣’果实主要矿质元素含量顺序均为:钾氮钙磷镁铁锌铜锰硼。测定的13个营养物质指标中铁、镁、钾、磷、氮、维生素C和总酸7个指标的含量‘骏枣’极显著高于‘灰枣’,钙和总糖2个指标的含量‘骏枣’与‘灰枣’无差异;硼、锌、铜、锰4个指标的含量‘灰枣’较‘骏枣’高,但无显著差异。果实的矿质元素、总糖、总酸和维生素C共13个指标的72组相关性数据中,‘灰枣’72组全部存在相关性,其中35组具有显著相关性;‘骏枣’有71组数据存在相关性,其中30组具有显著相关性。喀什‘灰枣’和‘骏枣’果实中矿质元素、总糖、总酸和维生素C等因子之间是既有协同作用,又有相互抑制,果实品质形成是各营养物质协同调控的结果。     

植物生长调节剂处理对黄冠梨糖、酸含量的影响

以黄冠梨果实为试验材料,研究不同植物生长调节剂对黄冠梨果实糖、酸含量及其变化的影响。结果表明:生长调节剂处理果实中糖、酸变化趋势与套3层袋的对照果实一致。在花后60～70 d,IAA和GA4+7处理果实中葡萄糖、果糖和可溶性糖含量显著高于套3层袋的对照果实,但果实成熟时,没有显著性差异。GA3和GA4+7处理蔗糖含量从花后100～110 d显著高于套3层袋的对照。果实成熟时,GA3处理果实苹果酸和有机酸含量显著高于对照果实,NAA、IAA和GA4+7处理与对照无显著差异,不同类型生长调节剂处理对果实中莽草酸含量无显著影响。     

不同缺素处理对库尔勒香梨果实品质的影响

在田间条件下,对20年树龄库尔勒香梨设置不同缺素的施肥处理,研究营养元素缺乏胁迫下库尔勒香梨果实品质的变化。结果表明：施肥能明显促进香梨果实的生长发育,提高单果重和产量;改善香梨果实形状,提高香梨红晕果率及果实中还原糖和维生素C的含量;降低香梨果皮厚度、果实硬度及果实中总酸的含量。香梨果皮厚度、果实硬度、单果重和产量的施肥效应N＞K＞P;果形指数、红晕果率及果实中还原糖和维生素C含量的施肥效应K＞P＞N;果实中总酸含量的施肥效应N＞P＞K。     

桃果实发育过程中主要糖及有机酸含量的变化分析

为了研究桃果实发育过程中可溶性糖及有机酸的变化规律,以21份各类型桃种质为试材,采用高效液相色谱测定果实发育过程中主要糖和有机酸含量。发现蔗糖含量在所有试材中均呈前期平稳或小幅增长,成熟前30~50d快速积累的趋势,部分品种采前小幅降低;各品种柠檬酸含量也呈类似的变化,前期最高,花后10~30 d均有显著的大幅下降,此后出现小幅的升高后平稳,采前大部分品种降低。果糖、葡萄糖、山梨醇、苹果酸、奎尼酸品种间差异大,且无明显的变化趋势。通过相关性分析发现,果实发育过程中,各试材蔗糖与果实大小均呈显著的正相关,有20个品种的果糖和葡萄糖含量呈显著的相关性;果实成熟时风味与蔗糖、pH、糖酸比之间存在极显著的正相关,与总糖含量呈显著的正相关,与可滴定酸、苹果酸、总酸存在极显著的负相关。     

不同倍性新麦草种子萌发特性的研究

与二倍体新麦草相比,染色体加倍后的四倍体新麦草的种苗生活力强,种子营养成分含量高,对低温、干旱等极端环境的适应能力强.对染色体加倍选育出的四倍体新麦草种子与正常的二倍体种子的萌发指标,幼苗芽长、根长、芽根比,以及种子萌发过程中淀粉酶活性和可溶性糖含量的变化进行了比较研究表明:四倍体新麦草种子在千粒重、发芽率、发芽势、活力指数和发芽指数等方面均显著高于二倍体种子(p＜0.01);染色体加倍能促进幼苗芽和根的生长,但对幼苗芽的促进作用更强;与二倍体新麦草种子相比,四倍体种子萌发过程中淀粉酶的活性更强,糖代谢速度快,更多的可溶性糖能给幼苗生长提供能量.     

Comparative study on vegetative,reproductive and qualitative traits of seven diploid and tetraploid watermelon lines

Seven tetraploid watermelon lines developed by colchicine treatments were compared with their diploid counterpart for plant, flower, fruit, seed and qualitative characteristics. Tetraploid genotypes attained statistically higher vine thickness (8.04 mm), leaf area (298.9 cm²) and chlorophyll content (55.6) while internode length and chlorophyll fluorescence was similar to their corresponding diploid. Both pistillate and staminate flower organs (pedicel, anther, ovary, stigma, petals) were larger in tetraploid plants; however, the percent increase in flower components varied across the tetraploid lines. Fruit weight and total sugar content (^∘Brix) in both ploidy fruits was similar. Rind thickness in fruits varied significantly and averaged 12.7 and 17.2 mm in diploid and tetraploid fruits, respectively. Tetraploid genotypes showed sterility, yielded lower number of seed per fruit (37.9), and tetraploid seed was larger and thicker than diploid seed. Overall β-carotene (0.89), lycopene (1.16), fructose (5.43%) and glucose (2.38%) contents were higher in tetraploid than diploid fruits.     

甜菜下胚轴颜色选择对后代品系及杂交组合的影响

为探讨甜菜幼苗下胚轴颜色与其他诸性状的相关关系,于1988—2003年对若干甜菜四倍体及二倍体多胚品系进行了4~6代幼苗下胚轴颜色的分离纯化选择、品系与原亲本比较、以红绿胚轴品系为亲本配制正反交组合等系列鉴定试验。结果表明,该选择方法对二倍体品系效果不明显,而四倍体后代品系与下胚轴颜色的联应F值达5%显著水平,红绿胚轴品系间的产、质量差异较大、互有高低,根产量相差20%以上,含糖率相差1%以上。绿胚轴品系含糖率大多数高于红胚轴品系,绿胚轴品系K、Na含量低于红胚轴品系,且大多达到1%或5%显著水准,而有害性氮含量则相反;红胚轴品系的株高、叶长、叶宽大于绿胚轴品系。利用四倍体和二倍体的红绿胚轴品系为亲本相互配制的杂交组合其产、质量存在显著差异。甜菜幼苗下胚轴颜色选择可以作为创新甜菜种质与品种选育的新方法,将下胚轴颜色作为品种的标记性状也很适用。     

Effects of selection in tetraploid green gram varieties

A comparative study of the effect of tetraploidy in three varieties of green gram (Phaseolus aureus Roxb.) and selection of plants with high, medium and low vigour showed that the reduced leaflet size and height at the time of flowering can be considerably improved by selection. It appeared that the diploid level can be approached or even exceeded.The reduced fruit setting can also be improved considerably but not the size of fruits and number of seeds per pod. The increased seed weight was further improved in two varieties. The increase in protein content of the tetraploid seeds was greatest in the variety with the lowest protein content at the diploid level.Though for vegetative growth selection alone would suffice to bring the tetraploids up to the diploid level, if not higher, the reduced fruit and seed setting, though responding well to selection, are unlikely to be overcome unless other breeding methods are introduced.     

Genetic and phenotypic correlations in plantain-banana euploid hybrids

The objective of this work was to determine intraclass correlations for growth and yield traits, as well as associations between them, in segregating hybrids. Diploid, triploid and tetraploid hybrids were obtained from triploid-diploid crosses between plantains and bananas. These hybrids were evaluated as plants and as ratoon crops on a humid forest site. Significant differences between ploidy within crosses were observed for most traits. The tetraploids were taller, had longer production cycles but a shorter fruit filling time, and heavier bunches than the diploids. There were significant differences between clones of the same ploidy within crosses. Hence, individual selection within ploidy will be effective for the improvement of plantain. Most of the bunch and fruit traits were positively and significantly associated, especially at the tetraploid level. Selection for large fruit at the diploid and tetraploid levels may lead to heavy fruits, thereby resulting in hybrids bearing heavy bunches. Significant and positive correlations between plant height and bunch weight at the tetraploid level suggest that selection of dwarf plantains with heavy bunches may be difficult.     

Studies on colchicine induced tetraploids of jute

Summary Colchicine induced tetraploid jute plants were shorter than their diploid counterparts. C₂ tetraploid plants became taller than C₁ plants. Leaves were larger in size and with higher breadth/length ratios compared to those of diploids. Stomata were bigger than those in diploid leaves but their frequency was less in tetraploid leaves. Tetraploid flowers were bigger than the diploids and bore a reduced number of stamens. Tetraploid pollen grains were larger but the percentage of sterility in them was more than that of the diploids. Fewer fruits with a reduced number of seeds were formed in tetraploid plants. They usually were shorter but wider than diploid fruits. Tetraploid seeds were larger and heavier. C₂ tetraploid plants bore more fruits with an increased number of seeds than C₁ plants. Breadth of individual fibres increased but length remained unchanged.The paper was read at the Eighth Pakistan Science Conference held at Dacca, 1956.     

Effects of Inbreeding and Genetic Variation on Forage Quality Traits and Dry Matter Yield in Dactylis glomerata L. Subspecies

Cultivated 4× clones, 2× germplasm and their respective S; progeny were utilized in this study. Dry matter yield and forage quality data (in vitro dry matter disappearance, cell wall constituents, total nitrogen) were obtained on composited vegetative plant material harvested during four successive 4-week growth periods in the greenhouse. There was no detectable average inbreeding effect for any of the traits. The group mean of the diploids was significantly lower for in vitro dry matter disappearance than the tetraploid group mean. However, two out of six diploid 51 families exceeded the highest tetraploid family for this trait. The diploids had significantly higher cell wall constituents than tetraploids except for acid detergent lignin. There was more variation for any trait at the diploid level than at the tetraploid level among S₁ families as well as within families. Dry matter yield and total nitrogen were significantly correlated in diploids and in tetraploids. However, little variation was detected lot total nitrogen at either ploidy level. The results suggest that selection for improved quality in progeny from interploidy crosses may be more efficient by first selecting at the diploid level followed by scaling to the tetraploid level, rather than selection at the tetraploid level after hybridization.     

不同倍性田埂报春DNA含量和叶绿素荧光特性研究

研究旨在以田埂报春二倍体及经秋水仙素加倍获得的同源四倍体为材料,比较2种倍性植物叶片DNA含量和叶绿素荧光参数的日变化规律。采用流式细胞测定法和叶绿素荧光技术进行测定,结果显示：（1）四倍体叶片细胞DNA的相对含量为二倍体的2倍。（2）四倍体的叶绿素a、b、总含量及类胡萝卜素含量都高于二倍体。（3）四倍体与二倍体的叶绿素荧光参数PSⅡ的原初光能转化效率(Fv/Fm)、 PSⅡ的潜在光化学效率(Fv/Fo)和以吸收光能为基础的光合性能指数(PI)值的日变化趋势相似,但四倍体的Fo小于二倍体。叶绿素总含量及类胡萝卜素含量、最大荧光、光化学效率、PSⅡ潜在活性和光性能指数均大于二倍体,田埂报春四倍体植株表现出优良的光合性能。     

青檀二倍体及人工诱导的同源四倍体遗传差异的AFLP分析

为了从DNA分子水平探讨二倍体青檀(2n=2x=18)与经秋水仙素诱变获得的同源四倍体青檀(2n=4x=36)在遗传结构上的差异,本研究以2x及同源4x青檀为实验材料,利用AFLP(Amplified Fragment Length Polymorphism) 分子标记技术,对供试材料的DNA多态性及遗传距离进行分析,结果表明：经秋水仙素诱变获得的同源4x青檀与2x青檀在DNA分子遗传结构上具有显著差异,2x青檀单株间DNA多态性在大于同源4x青檀,4x青檀单株间遗传距离在总体水平上大于2x青檀。本研究结果为进一步开展青檀多倍体育种、发挥青檀多倍体的优势提供理论依据。