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991.
加工型辣椒细菌性叶斑病病原菌生物学特性及抑菌药剂筛选 总被引:1,自引:0,他引:1
研究了新疆加工型辣椒细菌性斑点病病原菌Pseudomonas syringae pv .syringae 的部分生物学特征,并采用室内平板抑菌和盆栽试验对6种杀菌剂的防病效果进行了测定和筛选.结果表明,辣椒细菌性斑点病病原菌最适合生长的培养基为BPA培养基.25~30℃为适宜生长温度,最适温度为28℃.适宜在 pH6.5~8.0环境中生长,最适 pH 值为7.病原菌在1% NaCl浓度下生长良好,大于4% NaCl 生长受抑制.供试药剂的室内平板抑菌效果为:可杀得2000>乙酸铜>链霉素>志信101>红星-2氢氧化铜>志信2000,可杀得2000和乙酸铜的EC50值分别为5.954 mg/L和7.439 mg/L.盆栽试验结果显示,在发病前保护性喷施各药剂的防病效果(43.34%~80.84%)优于发病后治疗性施药(12.35%~49.54%),其中可杀得2000和红星-2氢氧化铜的防治效果较好. 相似文献
992.
YU Xiao-xia ZHAO Ning LI Hui JIE Qin ZHAI Hong HE Shao-zhen LI Qiang LIU Qing-chang 《中国农业科学(英文版)》2014,(2):310-315
Sweetpotato(Ipomoea batatas(L.)Lam.)breeding is challenging due to its genetic complexity.In the present study,interval mapping(IM)and multiple quantitative trait locus(QTL)model(MQM)analysis were used to identify QTLs for starch content with a mapping population consisting of 202 F1 individuals of a cross between Xushu 18,a cultivar susceptible to stem nematodes,with high yield and moderate starch,and Xu 781,which is resistant to stem nematodes,has low yield and high starch content.Six QTLs for starch content were mapped on six linkage groups of the Xu 781 map,explaining 9.1-38.8%of the variation.Especially,one of them,DMFN4,accounted for 38.8%of starch content variation,which is the QTL that explains the highest phenotypic variation detected to date in sweetpotato.All of the six QTLs had a positive effect on the variation of the starch content,which indicated the inheritance derived from the parent Xu 781.Two QTLs for starch content were detected on two linkage groups of the Xushu 18 map,explaining 14.3 and 16.1%of the variation,respectively.They had a negative effect on the variation,indicating the inheritance derived from Xu 781.Seven of eight QTLs were co-localized with a single marker.This is the first report on the development of QTLs co-localized with a single marker in sweetpotato.These QTLs and their co-localized markers may be used in marker-assisted breeding for the starch content of sweetpotato. 相似文献
993.
LIU Ze-guang YAO Wei-yuan SHEN Xue-xue CHAO Kai-xiang FAN Yu LI Min-zhou WANG Bao-tong LI Qiang JING Jin-xue 《中国农业科学(英文版)》2014,(12):2577-2583
Stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating diseases of wheat throughout the world. H9020-1-6-8-3 is a translocation line originally developed from interspeciifc hybridization between wheat line 7182 and Psathyrostachys huashanica Keng and is resistant to most Pst races in China. To identify the resistance gene(s) in the translocation line, H9020-1-6-8-3 was crossed with susceptible cultivar Mingxian 169, and seedlings of the parents, F1, F2, F3, and BC1 generations were tested with prevalent Chinese Pst race CYR32 under controlled greenhouse conditions. The results indicated that there is a single dominant gene, temporarily designated as YrH9020a, conferring resistance to CYR32. The resistance gene was mapped by the F2 population from Mingxian 169/H9020-1-6-8-3. It was linked to six microsatellite markers, including Xbarc196, Xbarc202, Xbarc96, Xgpw4372, Xbarc21, and Xgdm141, lfanked by Xbarc96 and Xbarc202 with at 4.5 and 8.3 cM, respectively. Based on the chromosomal locations of these markers and the test of Chinese Spring (CS) nullitetrasomic and ditelosomic lines, the gene was assigned to chromosome 6D. According to the origin and the chromosomal location, YrH9020a might be a new resistance gene to stripe rust. The lfanking markers linked to YrH9020a could be useful for marker-assisted selection in breeding programs. 相似文献
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为进一步优选灰树花多糖的最佳提取工艺,研究了溶剂用量、提取时间及提取次数对灰树花多糖提取的影响。结果表明:通过提取方法的考查确定葡糖糖吸收曲线为Y=0.125 8 X+0.105 5(R2=0.999 2),浓度在0.021 4~0.128 4mg·mL-1时与吸收度呈良好的线性关系。采用正交设计,用硫酸-蒽酮法在波长618nm处测定其吸收度,通过灰树花多糖得率的计算最终确定灰树花多糖的最佳提取工艺为水煎煮2次,煎煮时间分别为第1次提取2.0h,第2次提取1.0h,加28倍水,该方法简单,重现性好,提取率高。 相似文献
999.
Yu Wu Ji Zhang Xiao-Juan Jin Jian-Min Gao Qiang Zhao 《Wood Science and Technology》2014,48(4):713-725
Nitrogen-enriched activated carbons were prepared from waste medium density fiberboard waste by using NaOH, K2CO3 and KOH. The content of nitrogen in the activated carbon was 0.92, 0.74 and 1.33 % by analysis. The influence of contact time, pH, Cr(VI) initial concentration and the amount of activated carbon on the Cr(VI) adsorption capacity were investigated. The maximum adsorption capacity of Cr(VI) could reach 89.21 mg/g at pH 2 and a contact time of 9 h. The kinetics adsorption followed nicely the pseudo-second-order rate expression. In adsorption isotherm, the Langmuir model fitted better than the Freundlich model. Pure Poplar activated carbon was also prepared as the adsorbent for Cr(VI) removal as control sample. This study indicated that the nitrogen-enriched activated carbon prepared from waste medium density fiberboard can be used effectively for the removal of Cr(VI) compound from aqueous solutions. 相似文献
1000.
Aitor Gastón Juan I. García-Viñas Alfredo J. Bravo-Fernández César López-Leiva Juan A. Oliet Sonia Roig Rafael Serrada 《New Forests》2014,45(5):641-653
An expert on local flora usually is the best option for plant species selection in most ecological restoration projects; although species selection often needs to be dealt with swiftly as well as on a limited budget, and obtaining the opinion of a local expert may not always be an economically viable alternative. In such cases, species distribution models (SDM) may offer a faster and more cost effective alternative. We asked six experts to rank native tree species according to their suitability at 24 forest sites. The predictive performance of the suitability rankings was evaluated by assessing their ability to discriminate present from absent species in the observed tree assemblages at each evaluation site. We used the area under the receiver operating characteristic curve to calculate the probability that the estimated suitability for a species present at a particular evaluation site is greater than the estimate for an absent species (both picked at random). Suitability rankings were also obtained from the predictions of SDM and the same procedure was used to estimate the predictive performance of the set of models at each site. The experts offered concordant suitability rankings at almost every evaluation site. There were no significant differences in the predictive performance of the SDM and four of the experts, although the SDM performed slightly better than the other two experts. Our results point to the suitability of the proposed species distribution modeling approach to obtain fast and cost effective recommendations for species selection in forest restoration projects. 相似文献