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葡萄叶片衰老过程中不同光质对其光合和叶绿体超微结构的影响 总被引:1,自引:0,他引:1
以栽植于日光温室中适宜延迟栽培的‘贝达’砧‘意大利’葡萄为试材,自2013年8月1日始至落叶(2014年1月31日)止每天分别进行红光和蓝光不同光质延长光照至24:00补光处理,以不补光作为对照,研究不同光质补光处理对葡萄叶片衰老过程中叶片的外观形态特征、叶绿素含量、净光合速率、F_v/F_m、可溶性蛋白质含量和叶绿体超微结构的影响,为叶片抗衰老技术的研发提供理论依据。研究结果表明:补充红光显著提高了叶片的叶绿素含量、净光合速率、F_v/F_m值和可溶性蛋白质含量,叶绿体基粒片层排列整齐有序,明显减缓了叶绿体超微结构的解体,显著延缓叶片衰老;补充蓝光处理前期显著降低了叶片的叶绿素含量、净光合速率、F_v/F_m值和可溶性蛋白质含量,破坏了叶绿体的超微结构,加速了植株的衰老进程;但在叶片衰老后期,叶绿素含量、净光合速率、F_v/F_m值和可溶性蛋白质含量逐渐高于对照,并且叶绿体的基粒片层比对照排列整齐有序,在一定程度上延缓了叶片衰老。补充蓝光处理的叶片可溶性蛋白质含量一直显著高于补充红光和对照。综上,补充红光处理有效延缓了叶片衰老进程,延长了叶片的生理功能期。 相似文献
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High feeding and growth rates in common octopus (Octopus vulgaris) fed formulated feeds with an improved amino acid profile and mixture of binders 下载免费PDF全文
Four semi‐moist formulated feeds were supplied to Octopus vulgaris subadults (664 ± 70 g; 18.4 ± 0.7°C) in two different experiments. In the experiment #1, two diets were prepared with a new mixture of binders (gelatine 150 g kg?1, starch 100 g kg?1 and gum 50 g kg?1). The GEL15‐Squid and GEL15‐Hake feeds included 100 g kg?1 freeze‐dried squid (Todarodes sagittatus) or hake (Merluccius sp.) respectively. Both feeds showed low water disintegration rates at 24 h (13.6–15.0% dry weight). The specific feeding rate was higher in animals fed GEL15‐Hake (2.7%BW day?1), but the growth and feed efficiency were significantly better in animals fed GEL15‐Squid (1.4%BW day?1 and 61.2% respectively; P < 0.05). The proximate composition of the digestive gland, carcass and whole animals was similar. In the experiment #2, the GEL15‐Squid amino acid profile was improved by replacing 50 g kg?1 gelatine by 50 g kg?1 freeze‐dried squid (GEL10‐Squid) or freeze‐dried fish (GEL10‐Fish). These feeds showed higher water disintegration rates (31.7–36.3% dry weight). The feeding rates (2.2–2.3%BW day?1), growth (1.5%BW day?1) and feed efficiency were similar for both diets. Total lipids were higher in the digestive gland and whole animals fed GEL10‐Fish diet (P < 0.05). Future effort could be directed towards alternative binders that allow improve amino acid balance with a minimum gelatine content or even supplementation trials including essential amino acids. 相似文献
4.
Effect of temperature on energetic demands during the last stages of embryonic development and early life of Octopus vulgaris (Cuvier, 1797) paralarvae 下载免费PDF全文
This study describes the effect of seasonal average temperatures (14 and 18°C) in the Ría of Vigo, on the utilization of external yolk over the last five Naef stages of development (XV–XX) for Octopus vulgaris embryos. Also, the transference of the outer yolk to the inner yolk sac, and its use during embryonic development and early life by O. vulgaris paralarvae. Temperature had a marked effect on embryonic development, except during stages XV–XIX (until the second inversion) where development time was the same (14 days), regardless of temperature. There were no significant differences in outer yolk decrease between consecutive Naef stages at 14°C and 18°C. Contrary, significant differences at all Naef stages from XV to XIX (both, with or without outer yolk) were observed for inner yolk between temperatures. A higher accumulation of inner yolk in embryos at 14°C was observed, due to lower yolk consumption. Paralarvae incubated at both temperatures were maintained independently at starvation during 4 days. At 18°C, a reduced accumulation of inner yolk, especially during Naef stage XIX, was observed. In 24 h old paralarvae, there was already significant higher inner yolk content at 14°C than at 18°C. Unfed paralarvae at 18°C lost weight faster than those at 14°C, due to higher energetic requirements. Finally, from these results, we propose a paralarvae rearing protocol during the first days after hatching and during the last five Naef stage (XV–XX) at lower temperatures, since the energy requirements are lower during the initial maturation stage. 相似文献
5.
为研究短蛸(Octopus ocellatus)的性选择行为,本研究利用14个多态性微卫星标记,对3个母本、176个子代及17个候选父本进行亲权鉴定,对3个家系中有子代和无子代雄蛸、子代比例高和子代比例低的雄蛸的各形态参数进行t检验,并对子代比例高和子代比例低的父本与母本的遗传相似性与遗传距离进行分析。结果显示,短蛸为多雌多雄的交配模式,为真正意义的雌性混交动物;雄蛸有无子代与其形态参数无相关性;子代比例与父本的形态大小参数无关,而与父母本的遗传相似性和遗传距离有关,父母本遗传相似性越高,遗传距离越小,后代比例越高。本研究为揭示短蛸交配前后的性选择机制提供了重要线索,也为海洋头足类动物的性选择机制研究提供了基础资料。 相似文献
6.
为明确番茄潜叶蛾Tuta absoluta(Meyrick)成虫触角及幼虫头部感受器的种类、分布和形态结构,采用扫描电镜法观察番茄潜叶蛾雌雄成虫触角和4龄雌雄幼虫触角及口器上的感受器种类和形状。结果显示,番茄潜叶蛾成虫触角上共有8种类型感受器,分别为B?hm氏鬃毛、毛形感受器、鳞形感受器、锥形感受器(Ⅰ型和Ⅱ型)、刺形感受器、腔锥形感受器、栓锥形感受器和耳形感受器。其中,雌成虫的Ⅰ型和Ⅱ型锥形感受器数量、刺形感受器数量、B?hm氏鬃毛长度、鳞形感受器长度及基部直径、Ⅰ型锥形感受器长度及基部直径、Ⅱ型锥形感受器长度、刺形感受器臼状窝直径、腔锥形感受器基部直径和耳形感受器基部直径均显著大于雄成虫;而雄成虫的毛形感受器数量和腔锥形感受器中心锥长度显著大于雌成虫。幼虫头部共计有6种类型感受器,主要着生在触角、下颚和下唇上,分别为毛形感受器、锥形感受器、刺形感受器、栓锥形感受器、指形感受器和感觉锥;幼虫触角、下颚和下唇的感受器类型和数量在雌雄间完全相同。而雌性幼虫触角鞭节上的锥形感受器SB5和下颚须上的锥形感受器SB2的长度显著大于雄性幼虫;雄性幼虫下颚茎节上的刺形感受器Sch1和下颚须上的锥形... 相似文献
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Inoculation of wheat(Triticum aestivum L.) leaves with wheat powdery mildew fungus(Blumeria graminis f. sp. tritici) induces the cell death in adventitious roots. Reactive oxygen species(ROS) play a key role in respond to biotic stress in plants. To study the involvement of ROS and the degree of cell death in the wheat roots following inoculation, ROS levels and microstructure of root cells were analyzed in two wheat cultivars that are susceptible(Huamai 8) and resistant(Shenmai 8) to powdery mildew fungus. At 18 d after powdery mildew fungus inoculation, only Huamai 8 displayed the leaf lesions, while root cell death occurred in both varieties. Huamai 8 had a high level of ROS accumulation, which is associated with increased root cell degradation, while in Shenmai 8, there was little ROS accumulation correlating with slight root cell degradation. The molecular study about the expression levels of ROS scavenging genes(MnSOD and CAT) in wheat roots showed that these genes expression decreased after the leaves of wheat was inoculated. The difference between Huamai 8 and Shenmai 8 on subcellular localization of H2 O2 and O2–· was corresponded with the different down-regulation of the genes encoding for superoxide dismutase and catalase in two wheat cultivars. These results suggested that ROS were involved in the process by which powdery mildew fungus induced cell death in wheat roots. 相似文献
9.
斑马纹病是剑麻的主要病害之一,本研究以剑麻斑马纹病高感品种H.11648为材料,分别在接种烟草疫霉0、24、36、48、72 h取样,用电镜观察H.11648叶片细胞超微结构变化,同时分析过氧化氢酶(CAT)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、抗坏血酸过氧化物酶(APX)和超氧化物歧化酶(SOD)等防御酶活性变化情况。结果表明:H.11648在接种24 h,可见大量休止孢,叶绿体结构被破坏,植物组织开始降解,随着时间延长,附着孢出现,吸器形成,植物组织解体更严重,接种72 h,可见大量菌丝。在整个接种过程中,CAT、PAL和PPO活性显著增强,72 h达到最高,分别为501.44、25.73、1 742.67 U/(g.min)。SOD和APX活性显著下降,72 h达到最低,分别为2 888.62 U/g和841.96 μmol/(g.min)。POD活性先下降72 h又上升,但均显著低于接种前POD活性。本研究从细胞学和生理水平为探讨剑麻与烟草疫霉互作关系提供了理论基础。 相似文献
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水稻温敏型叶色突变体是研究植物光合作用、叶绿体结构和功能以及温度影响叶绿体发育的理想材料。利用甲基磺酸乙酯(EMS)诱变籼型水稻(OryzasativaL.)三系保持系西农1B,从其后代中筛选到一个突变性状稳定遗传的温敏型叶片白化转绿突变体tsa2 (temperature-sensitive green-revertible albino 2)。与野生型相比, tsa2突变表型受温度影响, 22°C条件下萌发的野生型幼苗表型正常,而tsa2幼苗完全白化,且约40%白化苗死亡,存活白化苗的光合色素含量、光合速率均显著降低,成熟期主要农艺性状均显著变劣;在28°C下萌发的tsa2幼苗叶片呈浅绿色并伴有白条纹,其光合色素含量显著降低,光合速率及主要农艺性状差异较小; 32°C下萌发的tsa2幼苗叶片无明显差异。透射电镜观察显示,与野生型相比,tsa2在22°C下叶肉细胞中无叶绿体或存在异常发育叶绿体(尚未分化出基粒和基层),在28°C下部分叶肉细胞含少量发育完整的叶绿体,在32°C下叶肉细胞数量及形态均正常。实时荧光定量PCR(qRT-PCR)分析表明,与野生型相比,tsa2突变体中部分光合色素代谢途径基因、叶绿体发育相关基因及光合作用相关基因的表达水平呈不同程度变化。遗传分析表明, tsa2突变表型受一对隐性核基因控制, TSA2被定位于第5染色体SSR标记S5-57和S5-119之间,物理距离为718 kb。本研究为水稻遗传改良及研究温度影响叶绿体发育机制奠定了基础。 相似文献