Metal leaching and toxicity of denitrifying woodchip bioreactor outflow—Potential reuse application

The denitrifying woodchip bioreactor is designed to remediate nitrate-rich water, including those produced from aquaculture effluents. Reuse of treated bioreactor outflows in recirculating aquaculture would offer considerable water savings and valuable alkalinity recuperation. However, such bioreactors may leach detrimental wood-bound contaminants, preventing outflow reuse. To determine water reuse potential, woodchip media from two hardwood species (white ash, Fraxinus americana; Norway maple, Acer platanoides) were evaluated for 206 d under a range of operating conditions (start-up, steady-state, reducing conditions, and drying-rewetting cycles) for a spectrum of potentially harmful dissolved contaminants. Aerated outflows also were evaluated for acute and chronic toxicity to the biologically sensitive invertebrate Ceriodaphnia dubia. Dissolved metal leaching subsided within the first few weeks of operation, though initial concentrations of copper and zinc were detected at concentrations of concern. Elevated concentrations of tannins-lignin and total ammonia nitrogen were detected throughout the study and were influenced by operational phase. Acute toxicity was not generally detected, though chronic toxicity was observed during drying-rewetting cycles in the maple outflows. The measured toxicity was not correlated with water chemistry, indicating an additive effect of several toxicants. Overall, significant differences in outflow water quality between ash and maple wood species were negligible. Results indicated that bioreactor outflows may be applicable for aquacultural reuse, though reusing outflows immediately following start-up or restarting after a dry period would not be recommended.     

Genetic variation of seedling traits responded to brassinosteroid and gibberellin inhibitors in maize (Zea mays) doubled haploid lines

The purpose of this study was to examine the genotypic variation in maize doubled haploid (DH) lines response to brassinosteroid and gibberellin inhibitors. Plant responses to hormone inhibitors were determined in growth chamber experiments using germination paper for three different seedling treatments: application of propiconazole (Pcz), uniconazole (Ucz) or water (control). Mesocotyl length (ML) was more sensitive to hormone inhibitors, especially to the Ucz treatment, than other seedling traits. ML was significantly correlated with other traits in the Ucz treatment. All the seedling traits showed moderate-to-high broad sense heritability values, ranging from 0.39 to 0.82. The Euclidian genetic distances of inbred line pairs ranged from 1.27 to 19.94, indicating there was a high level of variability across the maize DH lines used in this study. DH lines with extreme MLs were identified, which can provide valuable breeding resources for improving abiotic stress tolerance, and for further genetic studies.     

外源硅调控葡萄生理特性对低温胁迫的响应

本研究以大田葡萄品种‘梅鹿辄’为试材,采用大田喷施硅酸钾与室内低温处理相结合的方法,测定不同温度下葡萄叶片生理指标的变化,研究外源硅酸钾调控葡萄生理特性对低温胁迫的响应,探讨其提高葡萄抗寒性可能的作用机制。结果表明:低温胁迫下葡萄Inv活性被抑制,而其它指标则升高;喷施硅酸钾可显著降低低温胁迫下葡萄叶片的MDA含量,且当硅酸钾浓度为0.75%时对低温的损伤缓解作用最大;而脯氨酸、可溶性蛋白和可溶性糖含量、Inv、SPS活性及SS净活性均随硅酸钾浓度的升高而显著提高,但是可溶性蛋白含量在硅酸钾浓度为0.50%时最大,其它指标均在浓度为0.75%时最大;通过葡萄叶片各抗寒指标的隶属度值与综合评价指标看出,始花期0.75%的硅酸钾处理后葡萄抗寒性最强。综合分析,喷施硅酸钾可提高低温胁迫下葡萄叶片渗透调节物质含量,加快蔗糖转运及代谢速率,缓解活性氧累积,增强其耐寒性。     

Radiation-Induced Breeding in Camelina Sativa

Journal of Crop Science and Biotechnology - The ionizing radiation methods, including X-rays, gamma rays, and neutrons to create variation is well established and used in major crops. Many...     

花生硬脂酰-ACP酸脱饱和基因FAB2表达的分子机制

FAB2位于油酸合成通路的上游,编码硬脂酰-ACP脱饱和酶,调控硬脂酸(C18:0)向油酸(C18:1)转化。本研究发现高油酸品种开农176种子发育前期FAB2的表达量升高,而成熟期油酸过量积累会抑制FAB2的表达。利用开农176与开农70构建F2杂交群体,发现当植株油酸含量超过60%时会从整体水平上抑制FAB2的表达。种子发育前期,油酸不断积累会导致过氧化物酶活性升高,并且活性氧含量随之增加;但是在种子发育后期均降低,该结果与FAB2的表达量变化趋势相同。亚细胞定位结果表明, FAB2与FAD2分别定位于叶绿体与内质网。FAB2编码区序列多态性分析显示,该蛋白序列氮端的氨基酸结构缺失可能会导致硬脂酸含量升高。FAB2启动子序列存在大量AT碱基的富集区域,并且含有光响应、激素调控、转录因子结合的保守顺式元件。本研究发现过量积累的油酸会激活过氧化物酶介导的活性氧信号途径,进而通过细胞核内的未知转录因子调节上游基因FAB2的表达量,该结果不仅拓展了对FAB2的功能认知,也为培育高油酸花生品种提供了相关的理论指导。     

红掌新品种‘夏焰’

‘夏焰’红掌是从‘亚利桑那’为母本，‘大哥大’为父本的杂交后代中选出的盆花新品种。平均株高为48.32 cm；叶片中等大小，边缘略波皱，平均长24.45 cm，宽13.44 cm；佛焰苞红色，平展，富有光泽，平均长11.6 cm，宽9.2 cm，与花梗的角度近直角；肉穗花序平均长5.01 cm，白色至乳白色。从组培苗出瓶至成品花需16 ~ 18个月。     

晚熟苹果新品种‘华蜜’

苹果新品种‘华蜜’是以‘金冠’作母本，‘华富’作父本，杂交选育而成。果实圆锥形，果形指数1.1，平均单果质量220 g；果皮鲜红色，底色黄绿色，果面较光滑，果点中大；果肉较细，淡黄色，肉质松脆多汁，去皮硬度7.5 kg • cm-2，可溶性固形物含量17.5%，口感香甜，有香味，品质上等。果实生育期168 d左右，属晚熟品种，在辽宁省兴城地区10月下旬成熟，产量32 t • hm-2。     

茎用芥菜新品种1年2代繁育研究初报

为了探索福建省茎用芥菜1年2代繁育技术，选择6个茎用芥菜品种，分别进行冬春季正常繁育和夏秋季高山加代繁育的2代繁育试验，并对比各品种2代繁育的生育期、株高、株幅和种子产量。结果表明：所有参试茎用芥菜品种只要通过打破种子休眠、衔接好2代繁育的播种期都能完成1周年2代繁育，夏秋季高山加代繁育的全生育期比冬春季正常繁育平均缩短约50 d；冬春季繁育比夏秋季高山加代繁育株高增加31.2%～132.9%，株幅增加1.5%～21.8%，所有参试品种冬春季繁育的种子产量都极显著高于相应夏秋季高山加代繁育，种子产量增加17.8%～153.6%。     

Papaya yellow leaf curl virus: A newly identified begomovirus infecting Carica papaya L. from the Indian Subcontinent

India is one of the world’s largest producers of papaya. Viruses, mainly begomoviruses and potyviruses, cause a significant loss in papaya production. The study described here has identified a new species of begomovirus and a new species of betasatellite infecting Carica papaya in India. The sequences of the begomovirus and betasatellite show 90.03% nucleotide sequence identity to an isolate of Radish leaf curl virus and 92.25% identity to an isolate of Tomato leaf curl betasatellite, respectively. Maximum likelihood phylogenetic tree of begomovirus sequence of isolate DP2 (KX353622) showed distant relationships with previously characterised begomoviruses. Recombination analysis proposed six recombination breakpoints in begomovirus genome with other geographical begomovirus isolates.     

人工合成春小麦新品种龙春 166 及栽培技术

培育高产、优质、抗逆春小麦新品种一直是黑龙江省的育种目标。龙春166是黑龙江省农业科学院资源研究所利用人工合成小麦中的优异基因与普通小麦杂交和回交的方式选育的小麦新品种，整合了小麦近缘物种和普通小麦品种的优异性状，具有抗旱、秆强，抗倒伏、高产等特性。2019年通过黑龙江省农作物品种审定委员会审定，审定编号：黑审麦20190001。