吡虫啉在不同施药时间对玉米叶绿素含量的影响

对大田栽培作物玉米,在不同时间,用喷雾器喷施不同浓度杀虫剂吡虫啉,24h后测定玉米叶绿素和类胡萝卜素的含量.结果表明,上午喷施药剂促使玉米叶绿素含量增加最多,其次是中午,下午施药玉米叶绿素含量增加最小.     

Several field tests of Abate larvicides for Aedes control

Abstract

In preliminary field tests in woodlands swamps of southern Morava, ?SSR, it was found that Abate 500E at the rate 0.1 g/m² of water surfaces killed Aëdes vexans, A. cinereus and A. sticticus larvae 3 instar during 24 hours, but in other case at the rate 0.05 g/m² of water surfaces killed not the A. vexans pupae.

In southern Morava, CSSR a new larvicide, Abate^* was tested for Aëdes larvae and pupae control in the field. Abate (0,0,0¹,0¹ -tetramethyl 0,0¹ -thiodi-p-phenylene phosphorothioate) is an organophosphate insecticide that has been highly effective when tested against many different species of mosquito larvae. It is of very low toxicity to man and presents a minimum hazard in control. A well timed application of Abate will control the mosquito larva before it can develop into a pupa. Barnes and Webb (1968) applied one briquette of 0.58 g or 0.78 g/10 cu. ft. water in woodland pools, against Aëdes canadensis (Thio.). A. cantator (Coq.). A. vexans (Mg.) and Culex restuans Theo. Early spring treatment controlled all species as they normally appear in chronological sequence until early fall. One treatment of 6 pools gave excellent larval control throughout the 176-day test period; 23 pools were retreated on day 57, but this may have been unnecessary. No deleterious effects were noted on aquatic organisms. The US Department of Health and Welfare (1968) reports that 1% granules of Abate (0.002–0.06 lb/ac) satisfactorily kills A. vexans larvae. Lewis et al. (1965) applied 43% ec. and 1% granules of Abate (0.075 to 0.2 lb/ac; or 0.084 to 0.22 kg/ha) to log ponds. Both formulations gave excellent initial and residual (up to 18 days) control at dosages used. The e.c. seemed to act for a longer period. It was used for Culex peus Speiser, C. pipiens L., C. tarsalis (Coq.) and Culiseta larvae control.

In southern Morava Abate 500E, a 50% (W/v) emulsifiable concentrate containing 500 g a.i./l was tested in the woodland swamps – mosquito breeding places – against A. vexans, A. cinereus Mg. and A. sticticus (Mg.) instar larvae or A. vexans pupae.

In the first experiment 10g Abate 500E were used on 100 m² of water surface, mixed with water at 1:100. The insecticide was applied on two sites and a third chosen as control. Larvae were counted from 250 ml samples from each site. Table 1 shows the average number of larvae from each site.     

云南葡萄产区葡萄炭疽病病原鉴定及致病力分析

为了明确引起云南葡萄产区炭疽病的病原种类,利用形态鉴定和特异性引物分子检测相结合的方法对从云南省主要葡萄产区采集的60株炭疽病菌菌株进行了鉴定。葡萄炭疽病菌菌株的菌落形态和生长速率与对照菌株尖孢炭疽菌Colletotrichum acutatum差异不明显,但其分生孢子大小显著小于尖孢炭疽菌,附着胞深褐色,球形或不规则形。胶孢炭疽菌Colletotrichum gloeosporioides特异性引物CgInt/ITS4从供试葡萄炭疽病菌菌株基因组DNA中扩增出1条约500 bp的特异性条带,而尖孢炭疽菌特异性引物CaInt2/ITS4对葡萄炭疽病菌无扩增条带。研究表明,引起云南葡萄主产区炭疽病的病原为胶孢炭疽菌;供试胶孢炭疽菌对红提葡萄均有致病力,但菌株致病力差异较大,对番茄和草莓存在交叉侵染的能力,且对多菌灵的敏感性较尖孢炭疽菌高。     

寡雄腐霉发酵液对烤烟生长的影响及对烟草黑胫病的防治作用

为了探索对烟草黑胫病高效、稳定的生防制剂,利用寡雄腐霉工程菌株制备发酵液,采用温室盆栽试验研究该发酵液对烟苗生长的影响和对烟草黑胫病的防治作用。寡雄腐霉发酵液可提高正常烟苗生物量达22.6%,促进烟苗氮、磷、钾吸收;带病烟苗的发病率和病情指数分别降低了61.6%和64.2%,相对防治效果达64.2%;施用发酵液明显降低带病烟苗的细胞膜透性和丙二醛含量,提高烟叶多酚氧化酶、超氧化物歧化酶和苯丙氨酸解氨酶活性。说明寡雄腐霉发酵液可诱导烟株的防御作用,并提高其抗病能力和促生作用。     

Screening of cotton germplasm for resistance to Verticillium dahlia Kleb. under greenhouse and field conditions

Currently, the most effective and economically feasible means of controlling Verticillium wilt is to grow wilt-resistant cultivars. Nevertheless, resistant germplasm lines that are able to overcome this detrimental disease remain rare. Hence, we aimed to identify high-quality germplasm lines that exhibit high resistance, to address the dearth in optimum production. Our field and greenhouse studies showed significant variation among all tested germplasm lines with respect to wilt-assessment parameters. Highly resistant or resistant germplasm included 1421Bt-4133, O Siv2, Arcot-1, and GP93; Zhong 21371 and Yumian 2067 were moderately responsive; and Arcot402bne, Arcot438, Xinluzao-3, and Jimian11 were highly susceptible to wilt. Overall, germplasm line 1421Bt-4133 appeared to be an ideal material with strong resistance potential against V. dahliae. The germplasm lines O Siv2, Arcot-1, GP93, Zhong 21371, and Yumian 2067 showed variability in resistance potential in artificially or naturally-infested soil. This variability may be due to the genetic potential of the plants and to the adaptability of V. dahliae. We determined that the 1421Bt-4133 germplasm line was ideal, as it demonstrated resistance diversity against V. dahliae in all observed wilt-assessment parameters. The results of this study contribute to the understanding of viable germplasm lines for improving cotton production. The resistant germplasm lines uncovered in this study may provide new disease resistance sources in the breeding program.     

“一深两增”玉米高产模式下新品种产量潜力研究

为了给山西省春播中晚熟玉米区“一深两增”高产模式提供适用品种,选取大丰30、大丰26、强盛51、强盛101、福盛园52、并单390、潞玉36、先玉335、郑单958和北农110共10个品种为供试材料,研究了其产量构成因素及潜力.结果表明,强盛101及大丰26产量大于16 500 kg· hm-2,显著高于其他品种,且在采用“一深两增”高产模式下产量潜力分别达到19 148 kg.hm-2和17 691 kg.hm-2;强盛51、大丰30、福盛园52、先玉335和郑单958产量表现居中;并单390和潞玉36保苗率表现优异,均高于90％.除北农110外均可作为山西省中晚熟玉米区高水肥水浇地“一深两增”模式下的适用品种.     

小麦淀粉及其交联制备可降解膜研究进展

小麦淀粉具有独特的性质,但我国小麦淀粉改性及应用研究不多。白色污染的加剧,掀起了人们对环境友好型可降解膜的研究。寻求丰富的、可再生的、可降解的、易制膜的原料是制备可降解膜的关键。对小麦淀粉的生产工艺、交联变性反应以及可降解膜的制备进行了综述,对其研究与应用进行了展望。     

不同浓度啤酒废酵母酶解蛋白与硼砂组合对橘小实蝇的捕杀效果

于阳桃园和番石榴园,田间测定了不同浓度啤酒废酵母酶解蛋白与硼砂组合对橘小实蝇的诱捕和诱杀效果。结果表明:在诱捕和诱杀试验中,随着蛋白浓度和硼砂浓度的增加,酶解蛋白硼砂组合对橘小实蝇的捕杀数量呈逐渐增加趋势,以25 g/L蛋白、0.09 mol/L硼砂组合最高。通过诱捕和诱杀试验确定啤酒废酵母酶解蛋白的最佳田间使用浓度为20~25 g/L,硼砂的添加量为0.06~0.12 mol/L。     

2013年春季黑龙江省大豆市场分析及后市展望

受春季降水多、积雪厚、回暖晚的不利气象条件影响,2013年黑龙江省大豆播种延后1周以上。由于种植效益低,农民种豆积极性低,黑龙江省北部地区大豆面积继续保持下降趋势。在大豆市场方面,黑龙江省农民忙于春耕生产,加工企业多数停产,大豆市场购销停滞,大豆价格平稳回落。展望后市,进口大豆将供给充足,后期国内大豆价格震荡回落;国际大豆价格将呈现震荡走低格局。     

Fruit set after self-pollination at different floral stages and its relation to pollen-tube growth and stylar S-RNase content in Japanese apricot (Prunus mume Sieb. et Zucc.)

Summary

To investigate fruit set after self-pollination at different floral stages, and its relationship to the S-RNase content of the style in Japanese apricot, which exhibits gametophytic self-incompatibility (GSI), the cultivar ‘Xiyeqing’ was selfand cross-pollinated at –6, –4, –2, 0 and +2 d after anthesis (DAA). At –6 and –4 DAA, the percentage fruit set was low, suggesting that the propensity to seed set was weak during this period. At –2 DAA, the percentage fruit set, after self-pollination, reached a maximum of 5.97%. Thus, the effective time of self-pollination to obtain inbred seed was –2 DAA. Soluble protein extracts of styles at each floral stage were subjected to iso-electric focussing. The results showed that S-RNase began to be synthesized from –6 DAA, reached its maximum expression 2 – 3 d before anthesis, and was degraded slowly after anthesis. The number of pollen-tubes arriving at the stylar base, as detected by fluorescence microscopy, varied at –2, 0, and +2 DAA. The number of pollen-tubes arriving at the stylar base, and the percentage fruit set after self-pollination, exhibited a positive correlation (r = 0.8615; P = 0.1), while the S-RNase content per style showed a negative relationship to fruit set percentage (r = –0.9640; P = 0.01), and to the number of pollen tubes arriving at the stylar base (r = –0.9380; P = 0.01) during this period. This implied that the S-RNase content in the style was mainly responsible for the low percentage fruit set and the low number of pollen-tubes arriving at the stylar base after self-pollination.