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981.
Transgenic cry1Ab/vip3H+epsps Rice with Insect and Herbicide Resistance Acted No Adverse Impacts on the Population Growth of a Non-Target Herbivore,the White-Backed Planthopper,Under Laboratory and Field Conditions
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LU Zeng-bin HAN Nai-shun TIAN Jun-ce PENG Yu-fa HU Cui GUO Yu-yuan SHEN Zhicheng YE Gong-yin 《农业科学学报》2014,13(12):2678-2689
Numerous Bt rice lines expressing Cry protein derived from Bacillus thuringiensis Berliner (Bt) have been developed since 1989. However, the potential risks posed by Bt rice on non-target organisms still remain debate. The white-backed planthopper (WBPH), Sogatella furcifera (Horváth), is one of the most economically important insect pests of rice in Asian countries and also one of the main non-target herbivores of transgenic rice. In the current study, impacts of transgenic cry1Ab/vip3H+epsps rice (G6H1) with both insect and herbicide resistance on WBPH were evaluated to ascertain whether this transgenic rice line had potential risks for this sap-sucking pest under laboratory and field conditions. The laboratory results showed that no significant difference in egg developmental duration, nymphal survival rate and female fecundity was found for WBPH between G6H1 and its non-transgenic isoline (XS110). However, the development duration of nymphs was significantly shorter and female longevity significantly longer when WBPH fed on G6H1 by comparison with those on its control. To verify the results found in laboratory, a 3-yr field trial was conducted to monitor WBPH population using both the vacuum-suction machine and beat plate methods. Although the seasonal density of WBPH nymphs and total density of nymphs and adults were not significantly affected by transgenic rice regardless of the sampling methods, the seasonal density of WBPH adults in transgenic rice plots was slightly lower than that in the control when using the vacuum-suction machine. Based on these results both from laboratory and field, it is clear that our tested transgenic rice line will not lead higher population of WBPH. However, long-term field experiments to monitor the population dynamics of WPBH at large scale need to be conducted to confirm the present conclusions in future. 相似文献
982.
Yanting Cui Bo Liu Jun Xie Pao Xu H-Michael Habte-Tsion Yuanyuan Zhang 《Fish physiology and biochemistry》2014,40(3):721-729
In this study, we investigated the effects of hyperthermia and recovery on cell viability, lactate dehydrogenase (LDH) activity, superoxide dismutase (SOD) activity, malondialdehyde (MDA), total antioxidant capacity (T-AOC), and heat shock protein (HSP60, 70, and 90) mRNA expression in the hepatic cells of the grass carp, Ctenopharyngodon idellus. Triplicate groups of cultured cells were exposed to 30, 32, or 34 °C for 0.5 h and then immediately incubated at 27 °C in 5 % CO2 for 6, 12, 24, or 48 h. Hyperthermia stress greatly reduced cell viability and increased LDH release. Cell damage declined after recovery. Hyperthermia stress increased the lipid peroxide levels and reduced the antioxidant capacity (e.g., reduced SOD and T-AOC) of the cells. However, oxidative damage declined as the recovery period increased, and the levels of MDA, SOD, and T-AOC were restored. After cells were exposed to 32 °C, the expression of HSP60 after recovery for 1, 2, and 4 h (P < 0.05), the expression of HSP70 after recovery for 0.5 and 1 h (P < 0.01), and the expression of HSP90 throughout recovery were significantly higher (P < 0.01) than the prestress levels. During the recovery period, the variations in HSP gene expression reflected the transition period from a state of cellular growth to one of the cellular repairs. In conclusion, hyperthermia depresses cell viability, induces oxidative damage, and increases HSP expression, which plays an important role during hyperthermic stress in grass carp hepatic cells. 相似文献
983.
Yanting Cui Bo Liu Jun Xie Pao Xu Yuanyuan Zhang Jianhua Ming 《Aquaculture International》2014,22(3):1067-1077
The aim of the present study was to compare the expression pattern of heat-shock protein 60 (HSP60), 70 (HSP70), and 90 (HSP90) mRNA in hepatic cells of grass carp exposed to enrofloxacin and emodin concentrations. The expression pattern of different genes encoding heat-shock proteins in hepatic cells of grass carp was exposed to graded levels of enrofloxacin (12.5, 25, 50, 100, and 200 μg/ml) or emodin (0.04, 0.2, 1, 5, and 25 μg/ml) for 24 h and were investigated by real-time quantitative PCR. When cells were exposed to up 50 μg/ml enrofloxacin, both HSP60 and HSP70 mRNA levels firstly were increased and thereafter significantly dropped at high concentrations (P < 0.05), while HSP90 decreased with increasing enrofloxacin concentration. Besides, HSP60 and HSP70 expressions were significantly inhibited in the high-concentration groups. In addition, the HSP90 mRNA levels in the treatment exposed to 100 and 200 μg/ml enrofloxacin were significantly lower than those of the control group (P < 0.05). Furthermore, when cells were exposed to graded levels of emodin, HSPs (HSP60, 70, and 90) mRNA levels significantly increased in the groups exposed to 5 and 25 μg/ml of emodin. The different expression pattern of HSPs implied that enrofloxacin could inhibit the expression levels of HSPs, while optimal level of emodin could trigger higher expression levels of HSPs in hepatic cell of grass carp to protect against further damage. 相似文献
984.
挺水植物凋落物的分解会对湿地水质产生一定程度的影响。文中从挺水植物凋落物分解的研究方法、凋落物分解速率和元素释放以及分解与水体营养化水平的相互关系等几个方面,分析了挺水植物凋落物的分解特征。指出除了传统的分解袋法之外,一些新的技术和方法如近红外反射光谱(NIRS)法、同位素13C和15N示踪法也应用到植物凋落物的分解研究中;不同挺水植物凋落物的分解速率是不相同的,分解速率的不同致使凋落物元素释放的不同,且在分解过程中受到挺水植物凋落物特性和外界环境的影响。还分析了挺水植物凋落物独特的分解方式——立枯分解,指出挺水植物凋落物的分解可能会对水体造成二次污染,且不同植物的影响也是不同的。为了更好地保护环境,进一步提高水体质量,提出对挺水植物凋落物采取的相应措施,包括在植物生长末期清除部分植物凋落物,减少对水体的影响。还展望了今后在该领域研究的重点。 相似文献
985.
986.
为了鉴定经吡喹酮治疗有拉稀症状的丹顶鹤排出的吸虫种类,应用形态学结合分子生物学方法对该吸虫进行虫种鉴定。结果显示:该虫体形态与文献中报道的曲领棘缘吸虫的形态一致;所分离的吸虫ITS r DNA序列全长为1 083 bp,通过与NCBI上其他棘口科吸虫的ITS序列进行比对,表明该虫体与Echinostoma trivolvis的同源性可高达93%,属于棘口属吸虫,得出虫体鉴定结果为曲领棘缘吸虫,为鱼媒介寄生虫的防治提供参考依据。 相似文献
987.
988.
本研究旨在探讨3种不同类型的轻音乐对奶牛泌乳性能及能量代谢指标的影响。选用泌乳量、年龄、胎次、泌乳期相近的荷斯坦泌乳牛64头,随机分成4组,即轻音乐A(速度60 bmp的钢琴轻音乐《梁祝》,音色圆润)组、轻音乐B(速度70 bmp、小提琴演奏的泌乳牛情绪调控曲,音色明亮)组、轻音乐C(速度60 bmp、钢琴演奏的奶牛泌乳性能调控曲,音色圆润)组和对照组,每组16头。3个轻音乐组分别于早、中、晚3次挤奶前各播放音乐2 h,对照组无音乐播放。预试期7 d,正试期60 d。正试期每隔20 d测定泌乳量,并采集血样和乳样。结果表明:1)试验20、40 d及1~60 d,轻音乐A组、轻音乐B组和轻音乐C组奶牛干物质、有机物、中性洗涤纤维、酸性洗涤纤维、粗蛋白质和粗脂肪摄入量均高于对照组。2)试验1~60 d,轻音乐C组奶牛泌乳量、4%标准乳产量显著或极显著高于对照组(P0.05或P0.01)。3)试验1~60 d,轻音乐B组和轻音乐C组血液谷草转氨酶、丙氨酸转氨酶活性显著低于对照组(P0.05),轻音乐C组血液谷丙转氨酶、乳酸脱氢酶活性显著低于对照组(P0.05)。4)试验40、60 d,轻音乐C组奶牛血液甘油三酯含量显著高于对照组(P0.05);试验1~60 d,轻音乐C组奶牛血液葡萄糖含量显著高于对照组(P0.05);整个试验期,轻音乐A组、轻音乐B组和轻音乐C组奶牛血液游离脂肪酸含量均低于对照组,但差异不显著(P0.05)。综上所述,3种轻音乐均有提高奶牛营养物质摄入量、刺激泌乳及改善奶牛能量代谢指标的作用趋势;70 bmp的轻音乐较60 bmp的轻音乐对奶牛泌乳更为有利;与音色明亮的轻音乐相比,奶牛对音色圆润的轻音乐敏感性更高,音色圆润的轻音乐更能提高奶牛泌乳性能。 相似文献
989.
油菜和小麦种苗根系对乙草胺的耐性差异分析 总被引:1,自引:0,他引:1
为揭示油菜和小麦根系对乙草胺耐药性差异的原因,采用水培法研究了梯度浓度乙草胺对油菜和小麦种苗根系形态、根尖生理代谢和解剖结构的影响。结果表明,1 mg/L乙草胺对油菜根长抑制率为33.63%,而对小麦根长抑制率可达55.22%;100 mg/L乙草胺对油菜侧根抑制率为63.03%,而对小麦侧根抑制率达100.00%;经0.01 mg/L乙草胺处理后的油菜根尖细胞膜透性高于小麦,当乙草胺浓度高于0.1 mg/L后,小麦根尖细胞膜透性剧烈增加且高于油菜;在较高浓度乙草胺胁迫下,小麦根尖抗氧化酶活性均低于油菜;10 mg/L乙草胺处理下,小麦根尖的解剖结构变异较油菜明显,表现为细胞排列松散、混乱,根冠变形,分生组织细胞染色程度变浅,伸长区细胞分化提前,中柱鞘细胞木质化。研究表明,小麦的根系建成比油菜更容易受乙草胺抑制,且侧根数比根长更敏感;油菜和小麦对乙草胺耐药性差异可能与细胞膜透性、抗氧化酶活性以及根尖细胞组织分化等差异有关。 相似文献
990.
烤烟主栽品种‘K326’在打顶后,随着次生代谢产物的积累,烟草花叶病症状呈减轻趋势。本试验利用半叶枯斑法对‘K326’的全株、根、茎、叶甲醇提取物及根部不同极性溶剂萃取物进行抗烟草普通花叶病毒活性筛选,结果表明:在浓度为1mg/mL时,‘K326’各部位甲醇提取物中,根部甲醇提取物的活性最强,对TMV体外钝化、初侵染和复制增殖作用的抑制率分别为74.50%、68.82%和47.76%;利用不同极性溶剂对根部甲醇提取物萃取处理后,乙酸乙酯萃取物活性增强明显,对TMV体外钝化、初侵染和复制增殖作用的抑制率分别为76.81%、78.02%、61.42%;经普通烟‘K326’进一步验证,根部甲醇提取物的乙酸乙酯萃取物活性最强。综上,‘K326’中抗病毒防御物质可能存在于根部甲醇提取物的乙酸乙酯萃取物中。 相似文献