黄籽油菜因菜油的外观、品质好等优势深受消费者欢迎,但后代性状分离不稳定,严重影响其大面积应用。为解析黄籽油菜性状分离不稳定的内在原因,探寻黄籽油菜中黄色籽粒和黑色籽粒之间内在生理机制存在的差异,以甘蓝型黄籽油菜(CK)为材料...黄籽油菜因菜油的外观、品质好等优势深受消费者欢迎,但后代性状分离不稳定,严重影响其大面积应用。为解析黄籽油菜性状分离不稳定的内在原因,探寻黄籽油菜中黄色籽粒和黑色籽粒之间内在生理机制存在的差异,以甘蓝型黄籽油菜(CK)为材料,对其分离后代中的黄色(Y)、黑色(B)籽粒植株的农艺性状、生理生化指标、种皮颜色相关基因等之间的表达差异开展了研究。结果表明:分离后代中,Y的根茎粗和株高均优于CK和B,B的株高分别与CK、Y呈显著差异,B的根茎粗与Y呈显著差异。Y的病害指数为1.97,CK和B的病害指数分别为2.55,3.33,表明Y在抗病性方面优于CK和B。在9—10叶期Y叶片中的丙二醛(MDA)含量最低,花期Y和CK花中的过氧化物酶(POD)活性持续上升,表明黄籽油菜抗逆能力较强。7—8叶期和9—10叶期B和Y中TT18、TT8基因的表达量均高于CK,终花期B和Y中TT18基因的表达量显著低于CK。授粉后28 d Y种子中MYB47基因的表达量最高,分别为CK的5.56倍和B的5.79倍。TT8基因在授粉后21 d的Y中表达量最高,分别为CK和B的3.30,2.29倍。黄籽油菜在含油量、抗逆等方面均有明显优势,因而大力发展黄籽油菜可为提高菜油供应量,解决我国食用油安全提供新思路。展开更多
Alfalfa(Medicago sativa L.) is a legume forage that is widely cultivated owing to its high biomass yield and favorable nutrient values. However, alfalfa contains relatively high lignin, which limits its utilization.Do...Alfalfa(Medicago sativa L.) is a legume forage that is widely cultivated owing to its high biomass yield and favorable nutrient values. However, alfalfa contains relatively high lignin, which limits its utilization.Downregulation of two transcriptional factors, Transparent Testa8(TT8) and Homeobox12(HB12), has been proposed to reduce lignin content in alfalfa. Therefore, silencing of TT8(TT8i) and HB12(HB12i) in alfalfa was achieved by RNAi technology. The objective of this project was to determine effect of gene modification through silencing of TT8 and HB12 genes in alfalfa plants on lignin and phenolic content,bioenergic value, nutrient supply from rumen degradable and undegradable fractions, and in vitro ammonia production in response to the silencing of TT8 and HB12 genes in alfalfa. All gene silenced alfalfa plants(5 TT8i and 11 HB12i) were grown under greenhouse conditions with wild type as a control.Samples were analyzed for bioactive compounds, degradation fractions, truly digestible nutrients, energetic values and in vitro ammonia productions in ruminant systems. Furthermore, relationships between physiochemical, metabolic and fermentation characteristics and molecular spectral parameters were determined using vibrational molecular spectroscopy. Results showed that the HB12i had higher lignin, while TT8i had higher phenolics. Both silenced genotypes had higher rumen slowly degraded carbohydrate fractions and truly digestible neutral detergent fiber, but lower rumen degradable protein fractions. Moreover, the HB12i had lower truly digestible crude protein, energetic values and ammonia production compared with other silenced genotypes. In addition, in relation to the nutritive values of alfalfa, structural carbohydrate parameters were negatively correlated, whereas alpha/beta ratio in protein structure was positively correlated. Furthermore, good predictions were obtained for degradation of protein and carbohydrate fractions and energy values from molecular spectral parameters. In conclusion, silencing of the TT8 and HB12 genes decreased protein availability and increased fiber availability. Silencing of the HB12 gene also increased lignin and decreased energy and rumen ammonia production. Moreover, nutritional alterations were closely correlated with molecular spectral parameters. Therefore, gene modification through silencing the TT8 and HB12 genes in alfalfa influenced physiochemical, metabolic and fermentation characteristics.展开更多
文摘黄籽油菜因菜油的外观、品质好等优势深受消费者欢迎,但后代性状分离不稳定,严重影响其大面积应用。为解析黄籽油菜性状分离不稳定的内在原因,探寻黄籽油菜中黄色籽粒和黑色籽粒之间内在生理机制存在的差异,以甘蓝型黄籽油菜(CK)为材料,对其分离后代中的黄色(Y)、黑色(B)籽粒植株的农艺性状、生理生化指标、种皮颜色相关基因等之间的表达差异开展了研究。结果表明:分离后代中,Y的根茎粗和株高均优于CK和B,B的株高分别与CK、Y呈显著差异,B的根茎粗与Y呈显著差异。Y的病害指数为1.97,CK和B的病害指数分别为2.55,3.33,表明Y在抗病性方面优于CK和B。在9—10叶期Y叶片中的丙二醛(MDA)含量最低,花期Y和CK花中的过氧化物酶(POD)活性持续上升,表明黄籽油菜抗逆能力较强。7—8叶期和9—10叶期B和Y中TT18、TT8基因的表达量均高于CK,终花期B和Y中TT18基因的表达量显著低于CK。授粉后28 d Y种子中MYB47基因的表达量最高,分别为CK的5.56倍和B的5.79倍。TT8基因在授粉后21 d的Y中表达量最高,分别为CK和B的3.30,2.29倍。黄籽油菜在含油量、抗逆等方面均有明显优势,因而大力发展黄籽油菜可为提高菜油供应量,解决我国食用油安全提供新思路。
文摘Alfalfa(Medicago sativa L.) is a legume forage that is widely cultivated owing to its high biomass yield and favorable nutrient values. However, alfalfa contains relatively high lignin, which limits its utilization.Downregulation of two transcriptional factors, Transparent Testa8(TT8) and Homeobox12(HB12), has been proposed to reduce lignin content in alfalfa. Therefore, silencing of TT8(TT8i) and HB12(HB12i) in alfalfa was achieved by RNAi technology. The objective of this project was to determine effect of gene modification through silencing of TT8 and HB12 genes in alfalfa plants on lignin and phenolic content,bioenergic value, nutrient supply from rumen degradable and undegradable fractions, and in vitro ammonia production in response to the silencing of TT8 and HB12 genes in alfalfa. All gene silenced alfalfa plants(5 TT8i and 11 HB12i) were grown under greenhouse conditions with wild type as a control.Samples were analyzed for bioactive compounds, degradation fractions, truly digestible nutrients, energetic values and in vitro ammonia productions in ruminant systems. Furthermore, relationships between physiochemical, metabolic and fermentation characteristics and molecular spectral parameters were determined using vibrational molecular spectroscopy. Results showed that the HB12i had higher lignin, while TT8i had higher phenolics. Both silenced genotypes had higher rumen slowly degraded carbohydrate fractions and truly digestible neutral detergent fiber, but lower rumen degradable protein fractions. Moreover, the HB12i had lower truly digestible crude protein, energetic values and ammonia production compared with other silenced genotypes. In addition, in relation to the nutritive values of alfalfa, structural carbohydrate parameters were negatively correlated, whereas alpha/beta ratio in protein structure was positively correlated. Furthermore, good predictions were obtained for degradation of protein and carbohydrate fractions and energy values from molecular spectral parameters. In conclusion, silencing of the TT8 and HB12 genes decreased protein availability and increased fiber availability. Silencing of the HB12 gene also increased lignin and decreased energy and rumen ammonia production. Moreover, nutritional alterations were closely correlated with molecular spectral parameters. Therefore, gene modification through silencing the TT8 and HB12 genes in alfalfa influenced physiochemical, metabolic and fermentation characteristics.
