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1.
EPTC was tested in glasshouse and field experiments for its potential as a herbicide to control Bromus species in winter cereals. Bromus hordeaceus, Bromus commutatus, Bromus pectinatus and Bromus sterilis were all selectively controlled in barley by EPTC. Winter wheat was found to be susceptible but winter barley tolerated doses up to 2·0 kg a.i./ha. The barley cultivar Sonja was more resistant than both Athene and Maris Otter. In the first field trial, 1·0 kg a.i./ha EPTC reduced B. sterilis plant numbers by 75% giving a barley yield increase of 2·84 t/ha. In the following year 2·0 kg a.i./ha reduced B. sterilis numbers by 54% and increased yield by 1·75 t/ha. 相似文献
2.
《Crop Protection》1987,6(4):222-225
Several pesticides were evaluated singly and in combination or mixtures for their effectiveness against insects, nematodes, diseases and weeds in cowpea at Ibadan and Amakama in Nigeria. Of the granular insecticides/nematicides, carbofuran at 3·0 kg a.i./ha applied at planting reduced the population of thrips (Megalurothrips sjostedti) below control level up to 42 days after planting, but did not appear to translocate to the pods. Ethoprofos, isazophos and phorate were ineffective against thrips. Carbofuran also showed excellent control of the root-knot nematode, Meloidogyne incognita. The herbicides metolachlor and fluorodifen generally kept the plots weed-free up to 35 days after planting but had no effect on the nematodes. The fungicide benomyl applied as a seed treatment was not effective against web blight (Corticium solani) and brown blotch (Colletotrichum truncatum) but, when applied as a wettable powder in combination with monocrotophos as a foliar spray, offered effective control of the diseases and the combination gave the best grain yield across locations. The possible use of carbofuran with a cowpea variety that is resistant to larvae of the pod-boring moth (Maruca testulalis) is discussed. 相似文献
3.
P. Ayres 《Crop Protection》1985,4(2):263-271
Two experiments were conducted in which foliage-acting herbicides were applied to onion couch (Arrhenatherum elatius ssp. bulbosum). The first experiment used an artificially established population and investigated the effects of straw burning on the performance of autumn-applied treatments of glyphosate, aminotriazole and dalapon. Spring barley was sown without cultivation. The second experiment, conducted on a naturally occurring infestation, compared the performance of glyphosate applied at alternative autumn timings and a single application of flamprop-methyl made in the following spring, in the presence of a winter wheat crop. In the first experiment, assessments made after 15 months suggested that straw burning resulted in increased growth. In addition, herbicide performance appeared less effective after burning. In neither case were these differences significant. Glyphosate at 1·0 and 1·5 kg a.e./ha gave the highest levels of control of both shoots and bulbs, whereas control from aminotriazole at all doses (1·5, 3·0 and 4·5 kg a.i./ha) was poor. Dalapon (6·0, 12·0 and 18·0 kg a.i./ha) was intermediate in its effectiveness. In the second experiment, applications of glyphosate at 1·0 and 1·5 kg a.e./ha resulted in high levels of control of both shoots and bulbs with no significant difference between application dates. Flamprop-methyl at 0·52 kg a.i./ha reduced the number of shoots and bulbs by 55% and 58% respectively. All treatments significantly reduced the number of inflorescences present in July. 相似文献
4.
Field trials were conducted at Samaru in the northern Guinea and at Bakuta and Kadawa in the Sudan Savanna ecological zones of Nigeria to identify suitable herbicides for weed control in irrigated onion. The herbicides tested were chlorthal-dimethyl, fluorodifen and oxadiazon. In the trials each herbicide treatment was compared with an identical treatment which received supplementary hand-weeding. The results of these experiments show that oxadiazon at 1·0–2·0 kg a.i./ha, with or without supplementary hoe-weeding at 6 weeks after transplanting, combined effective weed control with high bulb yields in irrigated dry season onions. While fluorodifen at 1·5 kg a.i./ha followed by supplementary hoe-weeding may be effective at sites with low weed infestation, a higher rate (3·0 kg/ha) may be desirable at sites with a higher broad-leaved weed infestation. Chlorthaldimethyl at 10·0 kg a.i./ha effectively controlled weeds at all the sites and gave high onion yields at sites with 6–12% clay; the selectivity was, however, lower at Bakura with very light soil. Uncontrolled weed growth caused 49–86% reduction in the bulb yields compared with the best herbicide treatments. 相似文献
5.
《Field Crops Research》2003,83(1):91-100
An attempt is made to quantify the long-term benefit from the sustained production of sugarcane in South Africa using nematicides to reduce the damage caused by nematodes in each crop. The study was conducted using data from the plant crop and four or five ratoon crops from two trials located on similar sandy soils. Treatments comprised aldicarb and an untreated control, applied to a total of 10 sugarcane cultivars. Two cultivars were common to both sites. The plant parasitic nematode communities were similar at both sites except that Meloidogyne javanica was absent from one site. Yield of ratoon crops was correlated with the yield of the plant crop. Annual losses from nematodes were similar over successive crops. Data from both sites showed there to be a significant, positive correlation between yield of the nematicide treated plots and size of the response to treatment. Over a 4-year period, M. javanica alone was responsible for 30% of the losses, equivalent to 15 t cane/ha per year. The long-term effect of nematodes on sugarcane production was measured after calculating a logarithmic function from the observed yields of successive ratoons. Without a nematicide the time taken for the yield to decline to a threshold of 40 t cane/ha per year ranged from a minimum of 1 year in the M. javanica infested site to a maximum of 9 years in the other site. Treatment with a nematicide increased this period considerably. On the site with M. javanica it took a projected 20 years before the yield of one of the cultivars reached the threshold and 43 years for the same cultivar at the other site. The use of a nematicide increased long-term production, on average, by a factor of 3 at the M. javanica infested site and a factor of 5 at the other site. Differences between cultivars in the rate at which ratoon yields declined meant that, over time, the best cultivars at both sites were not the ones which gave the greatest annual yields during the first few crops after planting. 相似文献
6.
A.K. Oswald 《Crop Protection》1985,4(3):329-336
Asulam applied in April 1981 and 1982 gave good control of established plants of Bromus sterilis growing in Italian and perennial ryegrass crops grown for seed. Doses of 1–3 kg a.i./ha reduced numbers of weed inflorescences by 65–90%. The results also showed that there was no effect on crop heading and further suggested that seed yield had not been reduced. Two pot experiments also indicated the efficacy of asulam at 0·5-2 kg a.i./ha applied pre-emergence and further study of such treatment in the autumn during the establishment of a ryegrass seed crop is warranted. 相似文献
7.
Stem canker on germinating potato sprouts is often caused by seed-borne inoculum of the fungus Rhizoctonia solani. However, high amounts of free-living plant-parasitic nematodes have been found in field patches of potato plants with stem canker. Fungicide treatment of the seed tubers can be used to avoid stem canker caused by seed-borne inoculum but it is unknown if nematodes can affect this. To investigate whether free-living plant-parasitic nematodes, the root-lesion nematode Pratylenchus penetrans or a combination of several plant-parasitic nematode genera in a full nematode community, may have a negative effect on the fungicide seed treatment, a pot experiment with seed tubers inoculated with R. solani, half of which were treated with fungicides, was performed. The seed-borne inoculum caused severe damage to the plants, while no fungal damages were observed on the fungicide treated plants. This shows that the nematodes did not affect the fungicide treatment. The probability of black scurf decreased in treatments with a full nematode community, which may be due to the action of fungal-feeding nematodes. 相似文献
8.
Control of stripe rust (Puccinia striiformis) and common bunt (Tilletia caries and T. foetida) of wheat (Triticum aestivum), with fungicides applied on or adjacent to seed at sowing, was studied. Etaconazole pellets (2800 g a.i./ha), fenfuram liquid seed treatment (17 · 5 g a.i./ha) and imazalil granules (5000 g a.i./ha) were phytotoxic, reducing the number of heads per plot. All treatments reduced the incidence of common bunt although benomyl granules (2500 g a.i./ha), benomyl pellets (1400 g a.i./ha) and imazalil granules (5000 g a.i./ha) were not as effective as the registered smut fungicides carboxin, fenfuram, fenaminosulf and triadimefon. Triadimefon pellets (7000 g a.i./ha), PP347 pellets (1400 g a.i./ha), triadimefon granules (1500 g a.i./ha), flutriafol pellets (1400 g a.i./ha) and etaconazole pellets (2800 g a.i./ha) reduced stripe rust severity 17 weeks after sowing by 90, 89, 88, 86 and 74%, respectively. 相似文献
9.
Six insecticides (terbufos, chlorpyrifos, ethoprophos, phoxim, bendiocarb and lindane) were tested against sugar-cane wireworm Agrypnus variabilis (Candèze) in maize. The first five insecticides were applied at 0·25, 0·5 and 0·75 kg a.i./ha (2·27, 4·55 and 6·82 g a.i./100 metres of row) while lindane was applied at the registered rate of 0·29 kg a.i./ha (2·64 g a.i./100 metres of row). In addition, bendiocarb was applied as a seed treatment at the rates of 4000 and 6000 ppm. The insecticides were applied at planting as insecticide/fertilizer mixtures in 18 cm wide bands, 2–3 cm below the soil surface and 3–5 cm above the seed. The minimum effective rates were terbufos 0·25 kg a.i./ha, lindane 0·25 kg a.i./ha and chlorpyrifos and ethoprophos both at 0·5 kg a.i./ha. These treatments gave at least 5 weeks' residual control. The bendiocarb seed treatments were phytotoxic. No residues were detected in the cobs or grain at the minimum effective rates of the terbufos, chlorpyrifos or ethoprophos treatments. The positive linear relationship between plant population and yield showed that for every 1% loss in plant stand below the optimum range of 60 000–65 000 plants/ha, there is a 0·72-0·74% loss in grain yield respectively. Control measures would be economically justified with only a 2·3% reduction in plant stand (assuming $20/ha for cost of control and $150/tonne for maize). 相似文献
10.
Avoidable losses and economic injury levels (EILs) were computed for the sorghum head bug, Calocoris angustatus Leth., on three cultivars during three rainy seasons (1985–1987) at ICRISAT. Grain yield in plots protected with 2–5 insecticide sprays (carbaryl at 500 g a.i./ha) between the half-anthesis and the dough stage was significantly higher than in untreated plots, with cost-benefit ratios > 1. Plots that were not protected at half-anthesis and/or complete-anthesis, and at milk and dough stages, suffered a significant loss in yield. Bug damage spoiled the grain quality in terms of germination, 1000-grain mass, grain hardness and percentage floaters. Three to four sprays between complete-anthesis and the dough stage prevented a significant reduction in grain quality. Head bug density at half-anthesis, complete-anthesis, milk and dough stages was significantly and negatively associated with grain yield. Bug density at different stages explained 43–94% of the variance in yield. Direct effects of bug numbers at the milk stage and the indirect effects of head bug density at other stages through the milk stage contributed towards maximum reduction in yield. Maximum avoidable losses were recorded in cultivar ICSV 1 (88·6%), followed by CSH 1 (69·9%), and CSH 5 (53·9% in 1986 and 55·0% in 1987). Loss in grain yield/ha due to one insect/panicle at half-anthesis and that based on natural increase, were 548 and 232 kg in CSH 5 during 1986 and 1987, respectively, 251 kg in ICSV 1, and 77 kg in CSH 1. EILs based on a cost-benefit ratio of 1:1 ranged from 1·3–1·4 insects/panicle for CSH 1, 0·4 for ICSV 1, and 0·4–0·6 and 0·2–0·4 for CSH 5 during 1986 and 1987, respectively. Simple cost estimates for insecticide sprays and the resultant saving in grain yield are a useful tool for decision-making in pest management. 相似文献
11.
《Journal of Crop Improvement》2013,27(1):367-395
Summary In recent years, continuing environmental problems associated with the use of nematicides have resulted in a sense of urgency regarding the search for alternative methods of nematode control. Biological control of plant-parasitic nematodes with natural products from plants and animals, and soil organisms are alternative control tactics that are receiving increased interest among nematologists. Natural products include a number of plant parts, by-products, and residues when incorporating into soil, and plant-interculture with other crop plants, crop rotation with non-host or poor host of nematodes, green manuring and other organic manures. Nemato-toxic compounds of the different plants are released through volatilization, exudation, leaching and decomposition. Natural enemies as bio-control agents to nematodes include bacterial and fungal parasites, predatory nematodes and soil invertebrates. The beneficial effects of natural products have been generally considered to be due to direct or indirect stimulation of predators and parasites of nematodes. Very often, when there was a suppression in the nematode population, there was a consequent increase in crop production. 相似文献
12.
不同地区禾谷孢囊线虫对不同类型杀线剂的敏感性 总被引：1，自引：0，他引：1
为明确不同地区禾谷孢囊线虫对不同类型杀线剂的敏感性,采用浸渍法分别测定了灭线磷、噻唑膦、涕灭威、丁硫克百威、阿维菌素及甲维盐六种药剂对河南清丰、河北保定、安徽颍上、山东泰安和青岛五个地区的禾谷孢囊线虫二龄幼虫的室内毒力。结果表明,六种杀线剂对五个地区线虫的毒力表现为:甲维盐>阿维菌素>灭线磷>涕灭威>噻唑膦>丁硫克百威。灭线磷、噻唑膦、涕灭威和丁硫克百威对各地区线虫的LC50值都在582.7mg.L-1以上,不同地区线虫对同一药剂的敏感性存在一定差异,但相对毒力指数均在1.31以下;阿维菌素对各地区线虫的LC50值为26.0～66.3mg.L-1,甲维盐对各地区线虫的LC50值为20.1～35.3mg.L-1,不同地区线虫对这两种药剂的敏感性存在较大差异,相对毒力指数最高达2.55。 相似文献
13.
N.W. Forrester 《Crop Protection》1984,3(2):261-264
Isazophos applied as an in-furrow spray at 0·5, 0·75 and 1·0 kg a.i./ha (4·65, 6·98 and 9·3 g a.i./100 m of row) reduced the establishment of Yates NK 212 sorghum by 37, 61 and 75% respectively. Similarly, heptachlor at 1·12 kg a.i./ha (10·42 g a.i./100 m of row) and lindane at 0·29 kg a.i./ha (2·7 g a.i./100 m of row) reduced establishment by 24 and 57% respectively. Heptachlor and isazophos, applied at the same rates but as broadcast-incorporated sprays and the lowest rate of isazophos applied as an in-furrow spray (0·25 kg a.i./ha, 2·33 g a.i./100 m of row) were not phytotoxic. 相似文献
14.
S.W. Shires 《Crop Protection》1985,4(2):177-193
Cypermethrin (Ripcord 100 g a.i./ha), parathion-methyl (1000 g a.i./ha) and DDT (1000 g a.i./ha) were each applied to small replicated barriered plots of spring wheat. Residues of cypermethrin in soil declined to half their initial value within 6 weeks compared with 3 weeks for parathion-methyl and 22 weeks for DDT. No effects attributable to any of the three treatments were observed on earthworm populations or leaf litter decomposition. DDT was the only compound found to accumulate in the body tissues of earthworms. After application few cereal aphids were found in parathion-methyl- and cypermethrin-treated plots, whereas heavy infestations quickly built up in both the control and DDT-treated plots. One week after application the number of predatory beetles (mainly four species of Carabidae and three genera of Staphylinidae) in parathion-methyl-treated plots fell to about 10% of that found in the untreated control. A decrease in predatory beetles to about 50% of that in the control was observed in both cypermethrin and DDT-treated plots. A substantial recovery in the numbers of predatory beetles occurred in all treated plots between 4 and 6 weeks after application. A further fall in numbers of predatory beetles was observed 8–12 weeks after application in plots treated with cypermethrin and parathion-methyl. This reduction was attributed to an indirect effect of the treatments, operating via a removal of the predators' food supply (mainly cereal aphids). 相似文献
15.
P. N. P. Chow 《Crop Protection》1989,8(6):447-450
Broad-spectrum weed control by use of imazamethabenz (AC 222 293) in herbicide combinations was investigated in the greenhouse. Imazamethabenz at rates ranging from 0·1 to 0·4 kg a.i./ha effectively controlled wild oats (Avena fatua L.). Additional control of redroot pigweed (Amaranthus retroflexus L.) was achieved when imazamethabenz, plus octoxynol surfactant, was applied in combination with MCPA (amine or ester) or commercial MCPA mixtures (bromoxynil/MCPA and cyanazine/MCPA). Only inclusion of propanil/MCPA in the combination reduced wild-oat control by imazamethabenz at the lower rate (0·1 kg/ha). Control of green foxtail (Setaria viridis (L.) Beauv.) was also obtained by use of fenoxaprop-ethyl in combination with imazamethabenz (plus octoxynol). Three-way mixtures of imazamethabenz (or plus octoxynol), MCPA alone or mixture, and fenoxaprop-ethyl may provide practical control of grass and broad-leaved weeds in the field. 相似文献
16.
Brigitte T. Nyambo 《Crop Protection》1989,8(6):417-421
The introduction of ULV (ultra-low-volume) spraying to cotton farmers in western Tanzania in the early 1970s was a major contribution to the cotton industry as the control of cotton insect pests was made easier and possible in many areas. However, spray drift and increased cost of ULV insecticides and batteries have been major constraints to ULV spraying in recent years, so a spraying technique allowing greater efficacy and reduced costs is needed. Trials to assess the potential of electrodynamic spraying as an alternative to ULV spraying started in western Tanzania in 1979. The present study assessed swath width, dosage rates and farmer's reaction to the ‘Electrodyn’® hand-held sprayer as compared with the hand-held spinning-disc sprayer (Micron ULVA), currently used by farmers in Tanzania, in order to identify the optimum combination package to be recommended to farmers. Cypermethrin ED applied at a dosage rate of 15·8–31·6 g a.i./ha by the Electrodyn sprayer over a swath width of 3·0 m gave good control of H. armigera. Yields of seed cotton were comparable to those with ULV cypermethrin applied at a dosage rate of 62·5 g a.i./ha. The spray volume was reduced from 2·5 l/ha applied with the spinning disc to 0·35 l/ha with electrodynamic spraying. Reduced drift, dosage of active ingredient and volume rates, and reduction in the number of batteries needed in a season, were among the major advantages of electrodynamic spraying over ULV spraying in western Tanzania. 相似文献
17.
通过两年田间定位试验,采用裂区设计,设有机肥为主处理,氮肥为副处理,研究滴灌条件下有机肥与氮肥配施对玉米生长和产量的影响,滴灌条件下砂质土壤春玉米田有机肥和氮肥配施的最佳施用量,为土壤培肥、化肥减施以及提高宁夏扬黄灌区玉米产量提供理论依据。结果表明,玉米产量以有机肥3 000 kg/hm^2配施300 kg/hm^2氮肥处理最高,比不施肥处理增产50.65%;其次为有机肥4 500 kg/hm^2配施300 kg/hm^2氮肥和有机肥4 500 kg/hm^2配施225 kg/hm^2氮肥处理,分别较不施肥增产48.78%和46.83%。根据宁夏中部干旱带扬黄灌区土壤培肥和玉米增产需要,建议推荐有机肥施用量为3 000~4 500 kg/hm^2,配施氮肥用量225~300 kg/hm^2。 相似文献
18.
Summary The Netherlands have to cope with old and some new polyphagous nematode problems. A nematode control strategy based on an
economically sound crop rotation scheme to diminish the use of nematicides is necessary. For the development of such a strategy.
knowledge about host suitability and damage relationships of the various crops and weeds has to be revised and adapted for
new varieties and new cultural practices. For this purpose information gathered during the 1950's and the 1960's has to be
revised. With respect to the new nematode problems such information has to be obtained. In this integrated pest management
strategy nematicides are only applied when necessary and serve in this as a complementary emergency tool. With such an approach
in The Netherlands the use of nematicides has already dropped markedly. 相似文献
19.
Field experiments were conducted in the 2002/2003 and 2003/2004 dry seasons at the Irrigation Research Station of the Institute for Agricultural Research, Kadawa (11°39′N, 38°02′E, 500 m above sea level) in the Sudan Savanna Ecological Zone, Nigeria to study the effects of oxadiazon, date of planting and intra-row spacing on yields of garlic (Allium sativum L.) under irrigation at Kadawa, Nigeria. A uniform inter-row spacing of 15 cm was maintained in the two seasons. The results obtained showed that the hoe-weeded plots and application of oxadiazon at 1.5 and 2.0 kg a.i./ha resulted in comparable but significantly higher bulb yield per hectare, bulb diameter, bulb weight and number of cloves than oxadiazon at l.0 kg a.i./ha and unweeded check. Bulb yield per hectare, bulb diameter, bulb weight and number of cloves were higher at early November planting. Planting garlic at 5 cm intra-row spacing resulted in higher bulb yield in both seasons. 相似文献
20.
P. Kosma Z. Ambang B.A.D. BegoudeG.M. Ten Hoopen J. KuateA. Akoa 《Crop Protection》2011,30(6):733-738
Phytoparasitic nematodes of banana and plantain make one of the major constraints to sustainable banana and plantain production. The burrowing nematode, Radopholus similis, common in Cameroon is of particular importance where most smallholder farmers are unaware of this “hidden enemy”. In intensive plantain plantations, nematicides are often used as a primary means of control. Despite their efficacy, chemical pesticides are harmful to the environment and human health. The objective of this study was to assess the nematicidal properties of four neem seed formulations (raw neem seed powder (NSP); organic, watery and essential oil extracts) and to determine the phytochemical properties of these extracts. Alkaloids, saponins, triterpens and steroids were found in all three extracts, tannins in the organic and essential oils extracts and phenols only in the essential oils extract. Using five different concentrations of each of the three extracts as well as NSP, the nematicidal properties of all four formulations was confirmed. The NSP killed 100% of all nematodes at the lowest concentration tested, 10 μg ml−1, after 48 h. The in vivo test using two plantain varieties, Essong and Big Ebanga showed that all neem seed formulations increased plant growth and reduced nematode populations significantly when compared with the control. Since NSP seems to perform as well or even better than the extracts, it could provide farmers with a simple, low cost alternative for the control of banana and plantain nematodes. 相似文献