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排序方式: 共有193条查询结果,搜索用时 15 毫秒
141.
Fatima Ayoub Najwa Ben oujji Mohamed Ayoub Athman Hafidi Rachid Salghi Shehdeh Jodeh 《农业科学学报》2018,17(6):1401-1408
A new Integrated Pest Management program based on the combination of synthetic pesticide with a GRAS(generally recognized as safe)-classified sanitizer for the control of Botrytis cinerea in field conditions was described. The aim behind this research was to determine whether the use of this mixture would enhance the efficiency of pesticides while decreasing the recommended dose. Naturally infected tomato plants, grown in the greenhouse, were treated with two commonly used fungicides SWITCH(Syngenta, Switzerland) and SIGNUM(BASF, Germany) each alone or combined with a commercially available organic sanitizer PERACLEAN?5(Evonik Industries, Germany). A total of 27 treatments were tested consisting of three concentrations of synthetic fungicide(×1, ×1/2 and ×1/4 of the recommended dose) either applied separately or combined with three concentrations of the tested sanitizer(0.5, 1 and 1.5%). The control efficacy achieved by the fungicides applied alone ranged between 0 and 66.7% while all fungicide-sanitizer mixtures resulted in up to 70% control of grey mould. The treatment that provides the maximum control of B. cinerea was the result mixture of ×1/4 of the recommended concentration of SWITCH(15 g L~(–1)) with 0.5% of PERACLEAN~?5. This combination suppressed 85% of grey mold infections while decreasing the usually used amount of this pesticide by 75%, reducing therefore the well known negative impacts of chemical pesticides on environment and consumers health. 相似文献
142.
Amine Moubarik Antonio Pizzi Ahmed Allal Fatima Charrier Bertrand Charrier 《Industrial Crops and Products》2009,30(2):188-193
The aim of this work is to demonstrate the performances of cornstarch–quebracho tannin-based resins designed as adhesive in the plywood production. In this way, the cornstarch and quebracho tannin was introduced in the classic adhesive formulation in order to supply a part of phenol–formaldehyde (PF). The physical properties (rheological characterization, thermogravimetric analysis and solid phase 13C NMR analysis) of the formulated resins were measured. In order to evaluate the mechanical performances of optimal cornstarch–quebracho tannin-based resins, plywood panels were produced and mechanical properties were investigated. These mechanical properties included tensile strength, wood failure and 3-point bending strength. The performance of these panels is comparable to those of plywood panels commercial PF made.The results showed that plywood panels bonded with cornstarch–quebracho tannin–PF resins (15:5:80, w/w/w) exhibited better mechanical properties than plywood panels commercial PF made. The introduction of small proportions of cornstarch and quebracho tannin in PF resins contributes to the improvement of the boiling water performance of these adhesives. The formaldehyde emission levels obtained from panels bonded with cornstarch–quebracho tannin–PF were lower to those obtained from panels bonded with control PF. Solid state CPMAS NMR spectra indicates that no reaction at all between PF resins and cornstarch and quebracho tannin. Even when reaction does evidently not occur, the addition of cornstarch and quebracho tannin improves markedly the water resistance of PF resins. 相似文献
143.
Kayani S Zia M Sarwar S Riaz-ur-Rehman Chaudhary MF 《Pakistan journal of biological sciences: PJBS》2008,11(6):950-952
With the objective to promote in vitro callus induction, leaf segments of Achyranthes aspera were inoculated on basal MS medium supplemented with 3.0% sucrose and 0.8% agar with different concentrations of 2,4-D alone and in combination with NAA, BAP, IAA, IBA and Zeatin. The explants were maintained in growth room at 25 +/- 1 degrees C and 16 h light cycle. The best callus induction was obtained with 2,4-D (1.0 and 2.0 mg L(-l)) in combination with NAA (0.5 mg L(-1)). Callus induction and good texture from leaf explant was also observed at 2,4-D with BAP. On these combinations morphologically, light green, soft, compact and non-embryogenic callus (Type III callus) was observed. While morphology of callus and callogenic response was poor at 2,4-D alone or in combination with other hormones at different concentrations. 相似文献
144.
M. Sarwar Jahan G.H. Kanna S.P. Mun D.A. Nasima Chowdhury 《Industrial Crops and Products》2008,28(2):199-205
The differences in morphological and chemical characteristics and pulpability of core and bark fiber of jute at different position, top, middle and bottom were studied. The fiber length at the middle part of both bark and core was longer than the top and bottom part. With increasing height from bottom to top lignin content is decreased and α-cellulose content increased. The bark had higher α-cellulose and lower lignin than core. The bark produced nitrobenzene oxidation products with larger syringaldehyde/vanillin (S/V) ratios than the core. The yields of nitrobenzene oxidation products in bark were higher than core. The analysis of neutral sugars suggested that xylose is the predominant sugar of hemicellulose in both bark and core. The bark had higher glucose and lower xylose as compared to core. Under identical conditions of pulping, bark gave higher pulp yield and lower kappa number than core. The bark pulp showed better bleachability than core pulp. The higher tensile index in core pulp and higher tear index in bark pulp were observed. 相似文献
145.
Two new coumarin glycosides, named Rhodonin (1) and Rhodonetin (2) were isolated from the aerial parts of Rhododendron lepidotum. 相似文献
146.
Gislaine de Fatima Filla Emygdio Leite de Araujo Monteiro‐Filho 《水产资源保护:海洋与淡水生态系统》2009,19(7):772-778
- 1. Surveys were carried out between December 2004 and March 2006 on board tourism schooners to detect possible impacts due to tourist activities on estuarine dolphins (Sotalia guianensis) in the Estuarine Complex of Cananéia.
- 2. The estuarine dolphins exhibited different reactions according to the different periods of time that the boats remained close to them: the longer the period, the estuarine dolphins reacted less negatively, and for periods between 2 and 30 min, more positive reactions were observed.
- 3. Estuarine dolphin reactions also varied according to the different procedures followed by the skippers. The approach methods considered ‘correct’ resulted in a positive reaction from 97% of the animals encountered and 100% of occasions where there were no apparent reactions.
- 4. Direct approaches to within less than 50 m were responsible for a large number of negative reactions from the estuarine dolphins. Procedures classified as ‘chasing’ and ‘direct approach with no intention of stopping’ had a 100% negative reaction. If the skippers used a correct approach, estuarine dolphins reacted positively or did not show any reaction.
147.
148.
Boron requirement of mungbean was assessed from yield response curves based on field experiment during 2010-11. Four cultivars, i.e., NM-11, NM-2006, Chakwal Mung-2006 and AZRI Mung-2006 were grown in a boron (B)-deficient calcareous soil by applying B at 0, 0.5, 1.0, 2.0, and 4.0 kg ha?I. Boron application significantly increased grain yield and B uptake by all the mungbean cultivars over control. Maximum grain yield increases were: cv. NM-11, 20%; cv. NM-2006, 24%; cv. Chakwal Mung-2006, 26%; and cv. AZRI Mung-2006, 28%. The cultivars varied in B efficiency and cv. NM-11 was most B efficient (83%) while cv. AZRI Mung-2006 was the least B efficient (78%). Fertilizer B requirement (kg ha?1) for 95% of the maximum grain yield was: 0.60 for cv. AZRI Mung-2006, 0.70 for cv. Chakwal Mung-2006, 0.75 for cv. NM-2006, and 0.85 for cv. NM-11. Plant tissue critical B concentration in leaves was higher than in seeds. 相似文献
149.
Khalid P. Akhtar Ghulam SarwarGhulam Abbas Muhammad J. AsgharNighat Sarwar Tariq M. Shah 《Crop Protection》2011,30(9):1202-1209
Yellow mosaic disease (YMD) caused by whitefly (Bemisia tabaci) transmitted mungbean yellow mosaic India virus (MYMIV) is an important constraint of mungbean in Pakistan. One hundred sixty-two mungbean genotypes from eight different geographic regions were evaluated for resistance to MYMIV and its whitefly vector B. tabaci. Resistance levels were assessed by visual scoring of symptoms in the field under natural conditions, in net-house by artificial transmission through whitefly and in greenhouse using graft inoculation for two consecutive years in 2008 and 2009. None of the tested genotypes was found to be disease free, while considerable variation in responses was observed among the genotypes and testing methods. All genotypes were found to be systemically infected in the field. In 2008, 32 genotypes were found to be resistant and 67 were moderately resistant with severity index (SI) values ranging from 1.0 to 1.4 and from 1.5 to 2.4, respectively. In 2009 34 genotypes were found to be resistant and 38 were moderately resistant with the same SI value ranges as in 2008, and the remaining genotypes were moderately susceptible to highly susceptible. However, only 35 genotypes were found to be moderately resistant with SI values of 1.5-2.4 and latent periods (LP) of 17-21 days when evaluated using artificial transmission through whiteflies. Similar results were obtained when these genotypes were evaluated using graft inoculation. Significant differences in adult whitefly densities among tested genotypes were also observed during both years but no correlation between the number of whiteflies and disease severity was observed. The results indicated that these genotypes did not have a high level of resistance against MYMIV, however, they may provide sources of partial resistance which can be exploited in the breeding programmes to develop mungbean genotypes resistant to MYMD or they can be used directly as varieties to manage MYMD after evaluation for acceptable agronomic characteristics, adaptation and stability in various regions. 相似文献
150.
Qurban Ali Rind Abdul Ghani Lanjar Abdul Ghafoor Rahoo Ghulam Sarwar Solangi 吕荣华 付岗 覃武 《南方农业学报》2019,50(9):1973-1980
[目的]探讨亚金跳小蜂对不同生育期扶桑绵粉蚧的影响,为今后寄生蜂的饲养和推广及扶桑绵粉蚧的生物防治提供理论参考.[方法]分别以4个龄期的15头扶桑绵粉蚧、30头3龄幼虫和成虫为试虫进行选择性和非选择性试验,每虫笼放入1对亚金跳小蜂,每天记录寄主和寄生蜂的存活情况.[结果]亚金跳小蜂的最大寄生率和扶桑绵粉蚧的最大僵虫量均在扶桑绵粉蚧3龄若虫期出现,而最低值均在其2龄若虫期出现.在选择和非选择试验中,亚金跳小蜂雌虫的寿命差异不显著(P>0.05).在以扶桑绵粉蚧2龄若虫为试验对象的选择性和非选择性试验中,雌性亚金跳小蜂的生命周期分别为12.69±0.19和13.24±0.40 d.在以扶桑绵粉蚧3龄若虫为试验对象的选择性和非选择性试验中,雌性亚金跳小蜂的生命周期分别为15.51±0.28和15.12±0.14 d.寄生蜂的发育周期因寄主龄期而有明显差异,在扶桑绵粉蚧3龄若虫期寄生的亚金跳小蜂生命周期最长,而在扶桑绵粉蚧3龄若虫期寄生的亚金跳小蜂生命周期最短.[结论]作为寄生蜂的亚金跳小蜂在寄主扶桑绵粉蚧3龄若虫期的成虫量最大,在2龄若虫期的成虫量最小. 相似文献