5%d-柠檬烯SL对番茄烟粉虱的田间药效试验

为筛选出高效、安全防治温室烟粉虱的药剂及减少化学农药使用,以设施苗期番茄为试验材料,设置4个处理,分别为1.25、1.67、2.08 m L/kg的5%d-柠檬烯SL,0.17 m L/kg 25%噻虫嗪WP(常规使用的化学药剂),以清水为空白对照。结果显示:1.67 m L/kg 5%d-柠檬烯SL对烟粉虱防治效果较好,适宜推广使用。     

Promoting deep-sowing germinability of corn (Zea mays) by seed soaking with gibberellic acid

The effects of seed soaking with gibberellic acid (GA₃) on germinability of conventional corn variety ‘Nongda 108’ and super sweet corn variety ‘Chaotian 3’ were investigated under deep-sowing condition. GA₃ soaking significantly improved seed germination and mesocotyl elongation of both varieties under 10 or 6 cm sowing depth. The most significant promotion occurred at 0.175 g L^?1 GA₃ in ‘Nongda 108’ and 0.035 g L^?1 GA₃ in ‘Chaotian 3’. To further illustrate the physiological explanations, seed respiration was estimated from dehydrogenase activity test and oxygen-sensing test. Dehydrogenase activities of both varieties were dramatically promoted after GA₃ soaking. Compared with water soaking, the dehydrogenase activity in 0.175 g L^?1 GA₃-soaked seeds of ‘Nongda 108’ and 0.035 g L^?1 GA₃-soaked ones of ‘Chaotian 3’ was increased by 15.4% and 78.8%, respectively. Oxygen-sensing test showed that increased metabolism time (IMT) critical oxygen pressure (COP) and relative germination time (RGT) were decreased while oxygen metabolism rate (OMR) and relative germination rate (RGR) were increased in GA₃-soaked seeds, suggesting that exogenous GA-accelerated seed respiration. Our results suggested that seed soaking with exogenous GA₃ was a simple and practicable method to improve deep-sowing tolerance during corn seed germination, and the significant promotions were attributed to vigorous respiratory metabolism.     

花生浸种过程中水分相态和水分迁移动态研究

采用低场核磁共振（nuclear magnetic resonance,NMR）及成像（nuclear magnetic resonance imaging,MRI）技术对花生浸种过程中水分动态变化及水分传递进行了研究,考察花生浸种过程中横向驰豫时间(transverse relaxation time,T2 ) 和MRI图像的变化。结果显示,浸种期间,结合水弛豫时间和其幅值变化不大,说明花生种子在浸种过程中,种子内有机物与水分结合的数量从整体上相对稳定;自由水对应横向弛豫谱信号幅值不断增加,弛豫时间向右移动,表明花生在浸种过程中种子内部自由水数量不断增加,且其流动性增加。MRI图像显示,浸种过程中水最先从胚端部位进入种子,远胚端同样有水分浸入,但数量少于胚端,沿表皮进入种子内部的水扩散速度比较慢。本文建立了一种适合研究花生种子萌发期间水分动态变化的科学方法,丰富了花生种子吸胀期间对水分动态变化和代谢参与的研究,并为改善花生精准浸种和优化工艺提供有益参考。     

胚抢救技术在果树上的应用

胚抢救技术在果树早熟、无籽、三倍体类型育种及获得远缘杂种、阻止胚早期退化和缩短育种周期等方面具有重要作用。对胚抢救技术在果树作物育种中的应用及取得的成绩作了综述，并对胚抢救中应注意的几个问题，如适宜的培养时期、营养及环境条件作了简介，同时初步提出了果树胚抢救技术存在的不足及今后的研究方向。     

Boron Estimation in Soil,Plant, and Water Samples using Spectrophotometric Methods

Four spectrophotometric methods of boron (B) determination using azomethine-H, carmine, curcumin, and quinalizarin were compared to screen the most suitable one in estimating B concentration in diverse soils, plants and irrigation water samples. The azomethine-H method was the most sensitive in determining extractable B content of soils. All four methods, however, performed with equal efficiency for estimating B concentration in plant tissues. In the case of irrigation water, both carmine and azomethine-H were equally efficient in B determination. Natural concentration of interfering elements for the methods in all the tested soil, plant, and water samples were less than the tolerance limits. Because of sensitivity, ease of adaptation without using strong sulfuric acid, and rapidity, the azomethine-H method may be used for regular B determination in soil, plant, and irrigation water samples.     

Combining 1,4-dimethoxybenzene,the major flower volatile of wild strawberry Fragaria vesca,with the aggregation pheromone of the strawberry blossom weevil Anthonomus rubi improves attraction

The aggregation pheromone of strawberry blossom weevil [Anthonomus rubi Herbst (Col.: Curculionidae)], a 1:4:1 blend of Grandlure I, II and racemic lavadulol, has been available for pest monitoring for several years but shows low attractancy. Attempts to control A. rubi using the pheromone alone were also unsuccessful. This paper reports the finding that addition of the major flower volatile from wild strawberry flowers [Fragaria vesca L. (Rosaceae)], 1,4-dimethoxybenzene (comprising 98% of the volatiles emitted from wild strawberry flowers), to the aggregation pheromone increased trap catches by over two fold compared to the pheromone alone. There was no significant difference between the response of overwintered or summer emerged adults. Field trials in 2007–2008 in central and southern Norway, Denmark and southern England used green funnel traps with white cross vanes for the evaluations. (-)-Germacrene D, previously shown to be emitted by plants in increased amounts in the presence of pheromone producing weevils, did not improve trap catches. Thus, the combined use of the aggregation pheromone and 1,4-dimethoxybenzene is promising for improved monitoring and possibly control of this important pest of strawberry.     

Effect of microwave radiation on dry bean seed infected with Xanthomonas axonopodis pv. phaseoli with and without the use of chemical seed treatment

Common bacterial blight (Xanthomonas axonopodis pv. phaseoli) is a seed-borne disease that is difficult to control in dry bean (Phaseolus vulgaris L.). Laboratory and field studies were conducted over a two-year period to determine the effect of microwave radiation on navy (cv. Navigator and Envoy) and pinto (cv. AC Ole) bean. Laboratory tests resulted in a 12 to 25% decrease in germination following 50–60 s of radiation, while less than a 10% loss was observed between 0 and 40 s. Pathogen viability was also tested, however the incidence of pathogen infection was low and no correlation was observed between exposure time and the incidence of colonization. In field studies conducted at Morden, MB (2012) and Ridgetown and Exeter, ON (2012–2013) microwave radiation and two chemical seed treatments (copper hydroxide 53.8% and pyraclostrobin + fluxapyroxad + metalaxyl) were evaluated for their effect on emergence, disease infection, seed pick, yield and return on investment. The application of microwave treatment decreased emergence by up to 7%, but did not impact the other parameters measured. Chemical treatment alone or in combination with microwave treatment also did not affect emergence, disease incidence, yield, seed pick, or return on investment.     

辐照灭菌对10种中药有效成分含量的影响

用不同剂量的γ射线对10种中药材进行灭菌试验，并测定其辐照前后有效成分的变化。结果表明，灭菌剂量下的γ射线辐基本不影响10种中药材的有效成分含量。     

乙虫腈悬浮剂防治稻飞虱田间药效试验

乙虫腈悬浮剂防治田间稻飞虱试验结果表明，施用100 g/L乙虫腈悬浮剂600、525 、450 g/hm2对稻飞虱的防治效果均极显著优于对照药剂25% 噻嗪酮可湿性粉剂，药后第1、3、7天的防效分别达90.25%、92.40%、90.65%。100 g/L乙虫腈悬浮剂高效、安全，是防治稻飞虱的理想药剂，可大面积推广应用。