6种杀菌剂对马铃薯枯萎病菌的室内毒力测定

选择75%百菌清可湿性粉剂(WP)、36%甲霜灵锰锌悬浮剂(SC)、70%恶霉灵可湿性粉剂(WP)、50%甲基硫菌灵可湿性粉剂(WP)、6%春雷霉素可湿性粉剂(WP)、22.5%抑霉唑乳油(EC)6种杀菌剂对3种马铃薯枯萎病病原菌进行室内毒力测定。结果表明:6种药剂对病原菌菌丝生长的抑制效果差异很大,50%甲基硫菌灵(WP)和22.5%抑霉唑(EC)对3种病原菌的抑菌效果均很好,EC50分别为1.69、5.59、5.03μg/mL和3.60、5.17、1.58μg/mL。     

Fungicide efficacy of dry bean white mold [Sclerotinia sclerotiorum (Lib.) de Bary,causal organism] and economic analysis at moderate to high disease pressure

White mold [Sclerotinia sclerotiorum (Lib.) de Bary, causal organism] is an economically damaging disease of dry bean (Phaseolus vulgaris L.). Producers often require fungicides to control moderate to high disease levels. Evaluation of fungicide efficacy and cost is critical to make cognisant management decisions. Four field studies were conducted at the Huron Research Station, near Exeter, Ontario in 2012 and 2013. Commercially available synthetic fungicides and a biofungicide seed treatment were evaluated for efficacy in suppressing white mold of dry bean and a subsequent economic analysis was conducted. Area under the disease progress curve (AUDPC) was calculated using disease intensity (incidence × severity) ratings. The untreated control and biofungicide seed treatment had the highest AUDPC values, and in addition to the two applications of the low rate of fluxapyroxad + pyraclostrobin and two applications of penthiopyrad, had the lowest yields. The most efficacious products with regard to disease suppression and yield response were two applications of boscalid, all rates of fluazinam and thiophanate-methyl, and two applications of the high rate of fluopyram + prothioconazole. Two applications of the high rate of fluazinam had the lowest AUDPC, which was nearly 60% lower than the untreated control. Two applications of the high rate of thiophanate-methyl was the highest yielding treatment, recovering 70% of yield lost from untreated plots. Economic impacts varied with planting dates. For the first planting, profit margins for all fungicide treatments, with the exception of two applications of penthiopyrad, two applications of the low rate of fluxapyroxad + pyraclostrobin, and the biofungicide seed treatment, were significantly greater than the untreated control. For the second planting, only profit margins for all fluazinam treatments were significantly greater than the untreated control. This study identifies new economically viable fungicide options for dry bean producers to control white mold.     

Evaluation of the short term effect of nursery treatments with phosphite-based products,acibenzolar-S-methyl,pelleted Brassica carinata and biocontrol agents,against lettuce and cultivated rocket fusarium wilt under artificial inoculation and greenhouse conditions

Experimental trials have been carried out in order to evaluate the efficacy of preventative treatments based on plant defense activator products, biocontrol agents, a microbial complex with arbuscular mycorrhizal fungi, and Brassica carinata pellets against Fusarium oxysporum f. sp. lactucae race 1 on lettuce and Fusarium oxysporum f. sp. raphani on cultivated rocket under greenhouse conditions. These products were compared with fungicides known for their ability to induce host resistance (phosethyl-Al and acibenzolar-S-methyl), and with azoxystrobin. Three and four applications of the tested products were carried out on lettuce and rocket seedlings grown in nursery conditions. Treated and untreated plants were transplanted into soil infested with Fusarium wilt agents to obtain an average disease severity (DS) of 65.6–69.2 and of 56.9–62.1 on the untreated lettuce and rocket plants, respectively. The best Fusarium wilt biocontrol was obtained after four applications of Bacillus subtilis Qst713 and with the Glomas microbial complex (42 and 46.7%, efficacy, respectively). B. carinata pellets provided a consistent control when applied 14 days before the rocket and lettuce were transplanted into the infested soil. Acibenzolar-S-methyl, applied at 0.025 g/Liter, showed a DS reduction in F. oxysporum f. sp. lactucae from 36 to 61% and of F. oxysporum f. sp. raphani from 54 to 73%, thus showing statistically similar results to those of azoxystrobin, which was used as a reference (DS reduction from 59 to 65%). Although the Fusarium wilt control provided by such products was not complete in the present experimental conditions, these products can be considered interesting components for an integrated pest management of the Fusarium wilt of leafy vegetables, starting from nursey applications. Moreover, the tested BCAs could become potentially useful, especially for plant monocultures. This study has been produced new information on the effects of potassium phosphite, applied at the nursery level, on reducing lettuce and rocket fusarium wilt. An average efficacy of 69.5% was observed for lettuce, while an average efficacy of 65.2% was observed for cultivated rocket. The good fungicidal activity of the phosphite-based product, coupled with the positive effect on plant biomass, is of special interest.     

甜菜碱参与西瓜抗枯萎病的初步探究

为探究甜菜碱在参与西瓜抗枯萎病方面的作用,本研究以西瓜悬浮细胞为试验材料,利用镰刀菌酸诱导,测定细胞活性氧(ROS)的变化情况以及甜菜碱合成相关基因的表达变化等。结果表明:镰刀菌酸对西瓜细胞的生长有明显的抑制作用,通过外源添加甜菜碱可以缓解低浓度(≤100μmol/L)下镰刀菌酸的胁迫;通过镰刀菌酸诱导西瓜细胞,可以使细胞内ROS迅速升高,并在30 min达到最大值,而同时添加甜菜碱处理可以明显降低细胞ROS含量;此外,镰刀菌酸诱导可以使甜菜碱合成基因Cl BADH和Cl CMO基因表达量呈现先上升后缓慢下降的趋势,且0.5 h相对表达量达到最高,这证明镰刀菌酸对西瓜甜菜碱合成基因Cl BADH和Cl COM的表达有不同程度诱导作用。上述研究结果初步表明甜菜碱在参与西瓜抗枯萎病方面具有一定作用,为加强对西瓜枯萎病抗病机制的探索和发掘抗性相关基因提供了理论支持。      

Effects of fungicides on the occurrence of winter wheat eyespot caused by fungi Oculimacula acuformis and O. yallundae

The aim of this study was to estimate the effect of fungicides on the occurrence of Oculimacula spp. on winter wheat stems using real-time polymerase chain reaction (Real-time PCR) method. The ratio of Oculimacula yallundae and Oculimacula acuformis in the population was assessed from 2009 to 2011 in the winter wheat crops after 2, 3, and 4 years of use of fungicides prochloraz, cyprodinil, prothioconazole, metrafenone, and boscalid. After 4 years of fungicide use, the highest relative reduction of DNA of both fungi, compared with the unsprayed control, was detected in the samples from cyprodinil-applied plots. Relatively less O. yallundae DNA was identified in the samples from prochloraz- and that of O. acuformis from prothioconazole-applied plots. Metrafenone and boscalid had little effect on the changes in Oculimacula population. Fungicide effect on O. acuformis and O. yallundae pathogenesis slightly differed. In Oculimacula population under the fungicide treatment, 10 days after application (BBCH 37), the ratio of O. acuformis in all treatments was reduced, but the ratio of O. yallundae was increased in prevalence compared to O. acuformis in cyprodinil and prothioconazole treatments. Later in the season (BBCH 75), the ratio of O. acuformis increased in metrafenone and O. yallundae in prochloraz treatments. The effect of fungicides used for eyespot control on winter wheat productivity was inconsistent. Prochloraz use led to a significant grain yield increase in 2010, while prothioconazole use showed a similar increase in 2009 and 2010. Cyprodinil, boscalid, and metrafenone did not have any effect on the yield in any of the experimental years. A significant increase in thousand grain weight was obtained in prochloraz, prothioconazole, and boscalid treatments.     

河西走廊玉米苗枯病的发生规律及防治方法

经对河西走廊玉米制种产区苗枯病进行田间调查和病原菌形态、培养性状和致病性测定,结果表明:玉米苗枯病是由串珠镰刀菌(Fusarium moniliforme)、禾谷镰刀菌(F.graminearum)、玉米丝核菌(Rhizoctonia)等多种真菌复合侵染引起,其中河西地区主要以串珠镰刀菌(F.moniliforme)为主。带菌的种子和土壤是该病的初侵染来源,品种抗性差,苗期低温高湿及土壤肥力是影响发病的主要因素。选择抗病品种、种子药剂处理、加强肥水管理是防治玉米苗枯病的有效措施。其中以种子量0.15%的多菌灵、福美双等拌种,防治效果分别为94.13%、91.32%。     

不同砧木对西瓜枯萎病抗性及品质等的比较研究

为筛选西瓜抗枯萎病砧木,进行了不同砧木西瓜抗枯萎病接种实验及不同砧木嫁接苗田间长势、果实综合性状的研究。通过枯萎病接种实验,筛选出了6个高抗砧木,分别是N1、N6、H2、H5、X3与X4;在长势方面,嫁接苗明显强于自根苗,以南瓜为砧木的嫁接苗长势强于其他品种;在果实品质方面,各个品种的平均单果重差异不显著,且果型差异不大,但以H5(亲抗水瓜)、X3(大维根砧15号)和X4(勇士)可溶性固形物含量较高。综合研究认为,H5、X3和X4对枯萎病抗性较高,且长势较好,品质较优,综合表现较优。     

Methyl bromide alternatives for weed and soilborne disease management in tomato (Lycopersicon esculentum)

Two field trials were conducted to examine the efficacy of methyl bromide (MBr) alternatives in the control of Cyperus rotundus L. (purple nutsedge) and Fusarium oxysporum Schlecht. f.sp. lycopersici (Sacc.) Snyder & Hansen (Fusarium wilt) in fresh market tomato (Lycopersicon esculentum Mill.). Various treatments compared combinations of soil fumigants and herbicides based on methyl bromide, chloropicrin, 1,3-dichloropropene, metam sodium, dazomet, and pebulate. The data show that consistently 1,3-dichloropropene plus chloropicrin at both doses in combination with the herbicide pebulate can be considered alternatives to methyl bromide in fresh market tomato. These treatments had excellent purple nutsedge and Fusarium wilt control, and marketable tomato yields were similar to that for methyl bromide plus chloropicrin.     

Evaluation of spray programmes for the management of leaf spot incited by Pseudomonas syringae pv. syringae on tomato cv. Cuore di bue

Four experimental trials were carried out in northern Italy under greenhouse conditions against bacterial leaf spot of tomato, incited by Pseudomonas syringae pv. syringae, a disease recently observed in the country. The efficacy of spray programmes, based on the use of several copper-based compounds, acibenzolar-S-methyl, fosetyl Al and two biological control agents, Bacillus subtilis strain QST 713 and Pseudomonas chlororaphis MA 342, was tested. The best results were obtained with the alternation of copper oxychloride, used alone or in mixture with acibenzolar-S-methyl, with acibenzolar-S-methyl, applied for a total of two sprays. Acibenzolar-S-methyl applied alone was also effective. However, due to its possible slight phytotoxic effect, observed in our case in one trial, strategies relying on a limited number of its application are preferred. The efficacy of acibenzolar-S-methyl is higher under lower inoculum conditions. Among the tested copper-based fungicides, copper oxychloride provided the best and most consistent results, with no or limited phytotoxicity. Other copper compounds were much less effective and sometimes caused a reduction in plant height. The disease suppression achieved with B. subtilis strain QST 713 was only partial, while P. chlororaphis was not effective. The advantages of programmes based on rotation of copper compounds and acibenzolar-S-methyl are discussed.     

Sensitivity of Ascochyta rabiei populations to prothioconazole and thiabendazole

Ascochyta rabiei causes Ascochyta blight, a yield-limiting disease of chickpea (Cicer arietinum) world-wide. In 2007, fungal populations of A. rabiei resistant to the QoI group of fungicides were detected in the Northern Great Plains of the United States. Assays were conducted to determine fungal sensitivity for two alternative fungicidal modes of action. A total of 78 isolates of A. rabiei collected between 1983 and 2007 were screened to determine baseline sensitivity to the demethylation-inhibiting foliar fungicide, prothioconazole, and 100 isolates collected between 1987 and 2007 were screened for sensitivity to the methyl benzimidazole carbamate (MBC) fungicide, thiabendazole. Isolates were tested using an in vitro mycelial growth assay to determine the effective fungicide concentration at which 50% of fungal growth was inhibited (EC₅₀) for each isolate-fungicide combination. Baseline EC₅₀ values of prothioconazole ranged from 0.0526 to 0.2958 μg/ml, with a mean of 0.1783 μg/ml. Isolates of A. rabiei collected from 2007 to 2009 from North Dakota chickpea fields exposed to prothioconazole, were screened for prothioconazole sensitivity using the same assay. Mean EC₅₀ values for these isolates were 0.3544 μg/ml, 0.3746 μg/ml, and 0.7820 μg/ml, respectively. These values represent an approximate 2.0 (2007-2008) and 4.4-fold (2009) decrease in sensitivity from the baseline mean. EC₅₀ values of thiabendazole ranged from 1.192 to 3.819 μg/ml, with a mean of 2.459 μg/ml. No significant decrease in fungicide sensitivity was observed for thiabendazole. To date, no loss of Ascochyta blight control has been observed with the use of either prothioconazole or thiabendazole.     

Effect of annual sequence of removing or flaming potato vines and fumigating soil on verticillium wilt of potato

The effects of removing or flaming potato vines and soil fumigation on population density ofVerticillium dahliae in soil, severity of Verticillium wilt, and tuber yield were studied in a field near Alliston, Ontario, between 1993 and 1996. Vines were physically removed or flamed using a propane flamer in September just before harvest and soil was fumigated with metam-sodium (Vapam) at 550 L/ha in October after harvest. Vine removal had no effect on soil populations ofV. dahliae, area under the disease progress curve (AUDPC), or tuber yield. Flaming once (1993), twice (1993 and 1994), or three (1993,1994, and 1995) times reduced the soil population density ofV. dahliae, and flaming twice (1993 and 1994) reduced AUDPC compared to the nontreated control, but had no effect on tuber yield. Fumigation once (1993) or twice (1993 and 1994) reduced pathogen density in soil and AUDPC, but did not increase tuber yield. Fumigation once (1993) or twice (1993 and 1994), in combination with flaming twice (1993 and 1994), was equally and significantly effective in reducing both population density ofV. dahliae in soil and AUDPC values and in increasing tuber yield in 1995. Annual flaming of vines in combination with soil fumigation once (1993) or twice (1993 and 1994) in the fall improved the control of Verticillium wilt of potato and realised the greatest profits.     

Application of acibenzolar-S-methyl and standard fungicides for control of Phytophthora blight on squash

A plant systemic acquired resistance inducer, acibenzolar-S-methyl (ASM), was evaluated to determine the efficacy for suppression of Phytophthora blight of squash caused by Phytophthora capsici under field conditions. ASM was applied as foliar sprays before and after transplanting at rates of 17.5, 8.8, and 4.4 g a.i. ha⁻¹. Application of ASM did not significantly reduce final Phytophthora blight incidences in 2 out of 3 field experiments; however, area under the disease progress curve (AUDPC) values were reduced significantly by ASM in all experiments conducted. Disease suppression by the three application rates of ASM was not significantly different. To determine the effect of application of ASM in conjunction with standard chemical fungicides, ASM was applied with mefenoxam (Ridomil Gold), copper hydroxide, and mandipropamid (Revus). AUDPC values and final disease incidences were consistently lower in field plots treated by the combination of ASM and standard fungicides than applications of these chemicals alone. Application of ASM resulted in significantly higher squash yield than the non-treated control in 2 of 3 experiments and plots treated with the combined use of ASM and standard fungicides produced the highest yields. These results suggest that ASM may induce plant resistance under field conditions, providing suppression of Phytophthora blight of squash, and that there may be some benefit to the integration of ASM and standard chemical fungicides.     

Chemical control of Cylindrocladium and Rhizoctonia root rots in blueberry propagation

Cylindrocladium and Rhizoctonia root rots, caused by Cylindrocladium parasiticum and binucleate Rhizoctonia spp., respectively, are common soilborne diseases observed during blueberry propagation in Georgia, USA. Six trials with artificially inoculated propagation medium were completed in a shade-house to determine the efficacy of select fungicides to control these diseases. For Cylindrocladium root rot, two trials with single-drench fungicide applications were made at the time the cuttings (southern highbush blueberry cultivar Rebel) were stuck. In two additional trials, a second drench application was added two weeks later. In all trials, fludioxonil (Medallion) significantly reduced lesion incidence and lesion length. Neither triflumizole (Terraguard) nor thiophanate-methyl (Cleary's 3336) consistently reduced lesion incidence with one application, indicating that a single application of these materials was not sufficient for disease suppression. The second fungicide application improved disease control for all fungicides. However, fludioxonil always performed statistically better than thiophanate-methyl and numerically better than triflumizole as indicated by lesion incidence, lesion length and girdling incidence. For Rhizoctonia root rot, two trials were completed, each with two fungicide applications (when cuttings were stuck and 2 weeks later). Fludioxonil and azoxystrobin (Heritage) significantly reduced lesion incidence and lesion length in both trials. Flutolanil (Prostar) reduced lesion incidence in both trials and also reduced lesion length in the second trial. Pending labeling for this use pattern, fludioxonil, which has provided good control of both diseases in our trials, may form the basis of a fungicide rotation program to supplement sanitation practices for managing Cylindrocladium and Rhizoctonia root rots in blueberry propagation.     

Effects of agrochemical treatments on the occurrence of Fusarium ear rot and fumonisin contamination of maize in Southern Italy

The efficacy of agrochemical treatments, based on three different fungicides combined with an insecticide, was tested in southern Italy for two years on three maize hybrids to control Fusarium ear rot of maize and the accumulation in the maize kernels of the carcinogenic mycotoxins fumonisins. Insect damage incidence and severity, disease incidence and severity, identification of Fusarium species and levels of fumonisin contamination in kernels were determined. Field trials showed in both years that natural colonization of maize kernels by the fumonisin producing species Fusarium proliferatum and F. verticillioides (up to 81.5 and 26.5%, respectively) and total fumonisin contamination (up to 68.2 μg g⁻¹) were highly severe. For all hybrids and in both years, the treatment with the insecticide applied alone reduced the insect damage severity consistently and the content of fumonisins in the kernel only in half of the cases, whereas fungicide treatments applied in combination with the insecticide showed a further significant reduction of fumonisin contamination in the three hybrids and in both years.     

Evaluation of fungicides to control circular leaf spot of persimmon caused by Mycosphaerella nawae

The efficacy of ten fungicides against Mycosphaerella nawae, the causal agent of circular leaf spot (CLS) of persimmon, was evaluated in vitro and in field experiments. Field trials were conducted in 2009 and 2010 to investigate the comparative efficacy of the fungicides alone or combined using alternating sequences in spray programmes based on two, three or four applications. Disease incidence was assessed by estimating the percentage of affected leaves, which included leaves showing at least one necrotic spot and defoliation. Fenpropimorph, pyraclostrobin, tebuconazole and thiophanate-methyl were the most effective fungicides in inhibiting mycelial growth of M. nawae isolates (EC₅₀ < 2 ppm). In field experiments, the most effective fungicides using two spray applications were captan, chlorothalonil, mancozeb and pyraclostrobin which significantly reduced disease incidence compared with untreated plots. Regarding the number of spray applications, two applications of captan and mancozeb were less efficient than three to control the disease. However, the percentage of affected leaves provided by three applications of captan and mancozeb alone or combined with pyraclostrobin using alternating sequences in spray programmes, was not significantly different from that provided by four applications. Experimental results demonstrated that spray programmes based on three applications of these fungicides could effectively control CLS of persimmon. The advantages of spray programmes based on alternated use of strobilurins and protective fungicides are discussed.     

几种杀菌剂对西瓜枯萎病的室内毒力测定

采用生长速率法测定几种杀菌剂对西瓜枯萎病菌(Fusarium oxysporum Schlechtendahlex Fries f.sp.niveum(E.F.Smith)Snyder et Hansen)的室内毒力。结果表明：多粘类芽孢杆菌和甲基托布津的抑制效果最好,噁霉灵次之,咯菌腈最差;其中多粘类芽孢杆菌与甲基托布津的抑制效果相当,当多粘类芽孢杆菌浓度为25 000 mg/L时,抑制效果达为82.77%;其EC50值为506.176 4 mg/L。多粘类芽孢杆菌可作为大田防治西瓜枯萎病的防治药剂首选。     

Control of Fusarium wilt of carnation using organic amendments combined with soil solarization,and report of associated Fusarium species in southern Spain

Fusarium wilt is a disease that restricts carnation (Dianthus caryophyllus L.) yield worldwide. Efficacies in reducing the Fusarium wilt of carnation (FWC), of various types of organic amendments (fresh or pelletized poultry manure, pelletized Brassica carinata and olive residue compost) combined with soil solarization, were compared in two biennial field trials conducted in a greenhouse with a history of carnation monoculture over 8 years. Soil treatments combining organic amendments and soil solarization significantly reduced disease incidence (86–99%) and increased the number of commercial carnation stems by 5–9 times compared to non-treated plots. Twenty-one Fusarium spp. isolates, with different colony morphologies were recovered from soil samples taken in the greenhouse, before the application of treatments in June 2013. Nineteen of them were morphological and molecularly characterized. Additionally, two pathogenicity tests with 17 isolates recovered from greenhouse soils and two isolates recovered from organic amendments were performed. Fusarium species associated with carnation cultivation were identified as Fusarium oxysporum (43%), Fusarium proliferatum (24%), and Fusarium solani (33%). The phylogenetic analysis of the translation elongation factor 1 alpha (EF-1α) region distinguished highly aggressive isolates of F. oxysporum f. sp. dianthi, from low aggressive isolates. The pathogenicity tests showed that FWC has a complex etiology, with several Fusarium spp. identified as causal agents. F. proliferatum and F. solani are associated with carnation wilt for the first time in Spain.     

Influence of potato cultivars on the effectiveness of fungicide control of early blight

Three potato cultivars differing in degree of susceptibility to early blight were grown under crop management practices typical for Pennsylvania in 1987 and 1988. There were three experimental treatments: no fungicides, mancozeb with weekly applications initiated at 7 or 8 weeks after planting (early treatment), and weekly applications initiated at first symptoms of disease (late treatment). The no-fungicide control treatment had significantly higher AUDPC values than either treatment with fungicides and the no-fungicide treatment had significantly lower yield in 1987 but not in 1988. Tubers from the no-fungicide control had lower specific gravity. Norchip, the cultivar most susceptible to early blight examined in this study, responded the most in yield increases by the increased fungicide applications.     

不同施药模式对小麦产量、品质及效益的影响

为优化小麦病虫害防控技术,2008-2010年在成都平原开展了不同施药模式(CK:孕穗期和开花期喷施清水;T1:在孕穗期和开花期喷施杀菌剂防治病害;T2:在孕穗期和开花期喷施杀虫剂防治虫害;T3:在孕穗期和开花期分别喷施杀菌剂和杀虫剂防治病虫害;T4:在开花期一次性混合喷施杀虫剂和杀菌剂防治病虫害)试验,分析了不同处理间小麦病虫害、产量、品质及效益的差异。结果表明:(1)多数测试指标存在显著的年度效应,锈病病株率、白粉病病株率、降落值和多数RVA参数存在显著的年度与处理互作效应;(2)对照处理病虫害发生较重,单独喷施杀虫剂或杀菌剂均不能有效防控病虫危害,分次或混合施用杀虫剂和杀菌剂对病虫害的综合防控效果明显好于单独喷施;(3)施药处理较对照都有明显的增产、增收效果,产量增加6.9%～11.8%,纯收益增加4.3%～8.7%,以杀虫剂和杀菌剂分次喷施处理增幅最大;(4)施药处理对不同品质指标的影响存在较大差异,施药有降低湿面筋含量、沉降值和面团稳定时间的趋势,但都明显提高了降落值和RVA参数值。施药处理均未检出农药残留限值。综合产量、品质和效益,在选择抗病品种的基础上,于开花期实施多类药剂混合喷施不失为小麦节本高效的病虫防控措施。     

Interactions of agrochemicals applied to peanut; part 3: Effects on insecticides and prohexadione calcium

A wide range of agrochemicals can be applied in a peanut production system to control various stresses and manage crop growth and development. Field and laboratory experiments were conducted in North Carolina to define biological and physicochemical interactions when insecticides (fenpropathrin and lambda-cyhalothrin) or plant growth regulator (prohexadione calcium) were applied in combination with other agrochemicals including fungicides, herbicides, and micronutrients. Fenpropathrin or lambda-cyhalothrin combinations did not injure peanut in 2008 and 2009. Two sprays of prohexadione calcium improved row visibility and reduced main stem height compared with one prohexadione calcium spray irrespective of agrochemical combinations. In many instances, applying prohexadione calcium with other agrochemicals resulted in lower main stem height compared to prohexadione calcium alone. In one of the experiments, prohexadione calcium with prothioconazole plus tebuconazole lowered fall army worm population compared with prohexadione calcium alone. Addition of boron, manganese, and 2,4-DB to fenpropathrin, lambda-cyhalothrin, and prohexadione calcium combinations changed solution pH dramatically. Prohexadione calcium had the least effect on pH of the carrier.