扁杏皮对育肥羔羊饲粮养分消化率和血清脂质代谢的影响

为研究添加不同水平扁杏皮对育肥羔羊饲粮中营养物质表观消化率、血清脂质代谢指标的影响,本试验选择50日龄左右、体重相近、健康状况良好的小尾寒羊母羔80只,随机分为4组,每组5个重复,每个重复4只羔羊。对照组饲喂不含扁杏皮的饲粮,试验组分别饲喂含3%（A组）、6%（B组）和9%（C组）扁杏皮的饲粮,试验期60 d。当试验组羊平均体重约达30 kg时,每组选取4只羔羊进行消化代谢试验。试验期结束时,每组选取4只羔羊颈静脉采血,测定血清生化指标。结果表明：与对照组相比,A、B、C组育肥羔羊饲粮中粗蛋白质的表观消化率分别提高了3.56%、7.18%、4.08%（P < 0.05）,中性洗涤纤维的表观消化率分别提高了3.23%、8.04%、4.30%（P < 0.05）。B组育肥羔羊饲粮干物质和酸性洗涤纤维的表观消化率分别比对照组提高了5.39%和6.71%（P < 0.05）。各试验组间羔羊血清甘油三酯、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇的含量与对照组均无显著差异（P ＞ 0.05）|各试验组间羔羊血清中总胆固醇的含量均显著低于对照组（P < 0.05）。综上所述,饲粮中适量添加扁杏皮可以提高育肥羔羊饲粮养分的表观消化率,改善脂类代谢。本试验条件下,育肥羔羊饲粮中扁杏皮的最适添加量为6%。 [关键词] 扁杏皮|育肥羔羊|养分|表观消化率|血清脂质代谢     

山竹果皮多酚氧化酶酶学特性及抑制效应的研究

多酚氧化酶是酶促反应的关键酶,研究了山竹果皮中多酚氧化酶的活性及不同抑制剂的抑制效果。结果表明:山竹果皮多酚氧化酶的最适pH为5.5,最适温度为30℃,底物浓度与酶活性成正相关;抗坏血酸、亚硫酸氢钠、四硼酸钠、柠檬酸等对该酶表现出不同的抑制作用,抑制作用大小为抗坏血酸>亚硫酸氢钠>四硼酸钠>柠檬酸,抗坏血酸的浓度越高,对酶的抑制效果越明显。     

Transgressive variants for red pericarp grain with high yield potential derived from Oryza rufipogon × Oryza sativa: Field evaluation, screening for blast disease, QTL validation and background marker analysis for agronomic traits

Five transgressive variants (advanced breeding lines from BC₂F₅ and BC₂F₆ generation) were derived from a cross between the wild relative, O. rufipogon Griff. and O. sativa L. subsp. indica cv. MR219, a popular high yielding Malaysian rice cultivar. The aim of the study was to evaluate the pericarp colour of the grains along with yield potential and to validate quantitative trait loci (QTLs) for agronomic traits. The variants were screened against blast disease. Background marker analysis was also done for the promising variants. The field trials were carried out at a single location (due to containment purposes) over two seasons using randomized complete block design (RCBD) with three replications. A trait-based marker analysis was used to identify QTLs for validation in BC₂F₅ generation. Analysis of variance (ANOVA) showed that the seasonal factors influenced different agronomic traits. Variant G33 produced significantly (p < 0.05) higher yield (5.20 t/ha) than the control, MR219 (4.53 t/ha). Eighteen QTLs for different agronomic traits were identified in BC₂F₂ population in a previous study. Among them 14 QTLs were found in BC₂F₅ population of the present study. The yield of variant G33 was influenced by several QTLs viz. qGPL-1, qSPL-1-2, qSPL-8 and qYLD-4, which were introgressed from the donor parent revealed by background marker analysis using BC₂F₇ generation. Percentage (99%) of red pericarp grain of G33 and G34 in BC₂F₅ and BC₂F₆ generations indicated the stability of pericarp colour which was transferred from the wild relative. Variant G33 showed resistance against two pathotype of blast disease (Magnaporthe oryzae). Among the evaluated variants, G33 could be considered for inclusion in the cultivar development program for red rice with high yield potential and resistance to blast disease. This study demonstrated that the alleles from wild relative could improve the yield and yield related traits through allelic interaction, even though the phenotypic traits were inferior to the recurrent parent.     

不同致病力炭疽菌接种后荔枝果皮相关酶活性变化

【研究目的】为研究荔枝果皮接种不同致病力炭疽菌后,果皮内相关酶活性的变化情况;【方法】本研究用不同致病力炭疽菌株在荔枝果皮上进行了离体接种,以不接种的为对照,观察果皮内各种相关酶的活性变化;【结果】发现所有处理的果皮的总酚和花色素苷含量都逐渐降低,但在同一时间点时显著低于其他处理,变化幅度高于其它处理;PPO、POD和PAL活性都随接种时间的延长而增强,增强幅度和同一时间点的活性都明显较高;所有处理的CAT、APX、GR活性都增加,SOD活性下降,但接种强致病力菌株的酶活性增加和下降的幅度都比处理显著,活性也更高;所有处理的MDA含量都呈增加趋势,但接种强致病力菌株的含量和增加幅度都远大于其它处理;所有处理的PG、纤维素酶、CHT和β-1,3-葡聚糖苷酶的活性都随接种时间的延长而增加,接种强致病力菌株的处理中这几种酶的活性和增加幅度都显著高于其它处理;【结论】荔枝果实在不同致病性炭疽侵染后,果皮内酶活性变化显著.强致病性菌株引起的酶活性变化强度尤其强于弱致病力菌株和对照处理的果皮内酶活性变化。弱致病力菌株引起的酶活性变化与对照相比基本一致。     

东北唇形科(Lamiaceae)果实形态与解剖特征及其分类学价值

本文首次采用了GMA半薄切片和厚壁区域细胞分离法,深入研究了东北唇形科52种及5变种(位于4亚科26属)的果实形态结构。结果显示,果实多为三棱形,有的物种果实的棱延伸形成翅。果实表面光滑、具网纹或不同类型的毛状体(包括头状或盾状腺毛,单细胞、单列多细胞或分枝非腺毛)。着生面多为圆形,少为直线形或“V”形。果皮分为外果皮、中果皮、厚壁区域和内果皮。晶体常存在厚壁区域。本研究完善了东北唇形科果实形态学,并为进一步研究中国唇形科果实结构和分类学以及分子系统学奠定了基础。     

甜樱桃DFR基因内含子2和内含子3的多态性

【目的】研究70个甜樱桃品种DFR基因多态性与果皮颜色的相关性。【方法】通过DNA序列分析,以不同果皮颜色的10个甜樱桃品种（Prunus avium L.）为材料,检测DFR基因的多态性。根据多态性出现的位点设计特异引物,通过PCR扩增检测70个甜樱桃品种DFR基因的多态性。【结果】获得甜樱桃DFR基因约1 kb的片段,测序结果用BLAST分析发现,其核苷酸序列与樱桃李（Prunus cerasifera）的核苷酸相似性为80 %,预测的氨基酸序列与已知的甜樱桃（P. avium）DFR氨基酸序列相似性达99 %。该片段由3个外显子和3个内含子组成,2个多态性位点分别在内含子2和内含子3上。在黄色、黄底红晕和红色果皮3个组的70个甜樱桃品种中发现3个单倍型,共5种单倍型组合。通过SAS 9.0软件分析发现,所检测到的DFR基因的等位基因频率在黄底红晕果皮品种组和红色品种果皮组中的分布无显著差异。【结论】本研究在甜樱桃DFR基因座上得到2个差异位点,分别在内含子2和内含子3内,其优势基因频率依次为：0.864和0.679;但未发现DFR基因内含子2和内含子3的多态性与果皮颜色之间存在直接关系。     

低温结合保鲜剂处理对哈密瓜保鲜效果的研究

以沪产9818黄皮哈密瓜为试材,采用二氧化硫保鲜剂处理,以未做处理的哈密瓜室温条件贮藏为对照,研究分别在3,5,8℃低温条件下保鲜剂处理哈密瓜采后贮藏品质的变化。结果表明,SO2保鲜剂处理结合3℃下贮藏,可显著抑制9818黄皮的果实硬度及总酸、总糖和可溶性固形物含量的下降,贮藏20d时,总酸含量为0.082%,仍为贮藏前的81.6%;贮藏30d,总糖含量为11.6%,仍为贮藏前的93.5%,可溶性固形物含量是12.4%,显著高于9.1%的对照含量。SO2保鲜剂处理结合3℃贮藏保鲜的效果最佳,能够有效地保持哈密瓜的营养和外观品质,贮藏时间可达30d。     

Construction of Near Isogenic Lines for Pericarp Color and Evaluation on Their Near isogenicity in Rice

The inheritance of purple pericarp was studied through genetic analysis using F2, BC1F1 and F3 from a cross between a purple pericarp rice variety Zixiangnuo and a white pericarp rice variety Chunjiangnuo 2. Seven pairs of near isogenic lines (NILs) for pericarp color of rice were further constructed. Genetic analysis indicated that the purple pericarp was controlled by two complementary genes (Pb and Pp). Agronomic trait analysis and polymorphism analysis using SSR markers on these seven pairs of NILs were used in the evaluation of near-isogenicity. No significant differences in agronomic traits were found except 1000-grain weight between the NILs. The polymorphic SSR markers for the parents were only detected in target segments of the five pairs of NILs different in Pb, which revealed the ideal near isogenicity of them. However, for the two pairs of NILs different in Pp, the polymorphic markers for the two parents were detected as well as in non-targeted segments of chromosomes 11 and 12, respectively.     

玉米籽粒果皮厚度变化规律研究

采用显微测微法对3种不同基因型的7个玉米骨干系及由它们配制的4个杂交组合F1的果皮厚度变化规律进行了研究.结果表明:玉米籽粒发育过程中,果皮厚度呈曲线状态变化.即授粉后随着籽粒发育果皮逐渐变厚,到乳熟后期(超甜玉米)或蜡熟期(普甜玉米、普通玉米)达最大值,然后随着籽粒脱水,果皮细胞排列紧密而变薄;在广州地区春、秋正造种植时,环境不会从根本上改变果皮厚度这一性状;同一基因型内不同核背景材料间籽粒平均果皮厚度也有显著、极显著差异;杂交组合F1代种子果皮厚度似乎有母体效应.     

籼型黑米稻粒形性状与其中某些矿质元素含量的遗传相关性

采用禾谷类作物种子数量性状遗传模型, 分析籼型黑米稻品种双列杂交F1和F2种子粒形性状与其中矿质元素Fe、 Zn、 Mn和P含量间的多种遗传相关性. 结果表明, 籼型黑米粒重、粒长、粒宽、粒长/粒宽与其中Fe、 Zn、 Mn和P含量除存在明显的表现型相关和基因型相关外, 尚存在较明显的种子直接加性相关、直接显性相关、细胞质相关、