Pest and disease control on intensive apple trees by overhead mobile spraying

In 3 year field experiments on pest and disease control by mobile overhead spraying of intensive Cox's Orange Pippin apple trees, overhead booms applying 1125 litres/ha and overhead mist-blowing equipment applying 562 litres/ha, each spraying two complete rows from one alley in half the normal time, were compared with conventional automatic mast spraying at 2250 litres/ha and with conventional mist-blowing at 562 litres/ha. The overhead boom application of demeton-S-methyl (0.0036% a.i.) with azinphos-methyl (0.0165% a.i.) or of fenitrothion (0.031% a.i.) at the green cluster stage gave control of the applegrass aphid, Rhopalosiphum insertum, virtually equal to that obtained by conventional application of the same insecticides. Similarly, the overhead mist applications of conventional quantities of insecticides gave equal control, but not when applying one-quarter of the normal amount of insecticides. The conventional methods generally gave better control of apple sucker, Psylla mali. In 1971, when the incidence of apple scab, Venturia inaequalis, was only moderate, the overhead boom method gave equal control to conventional spraying with both dodine/captan (0.03% a.i. and 0.094% a.i.) and benomyl (0.025% a.i.) programmes: in 1972 and 1973, when the scab incidence was heavier, the overhead boom spraying was again equal to the conventional method with the benomyl programme but was less effective with the dodine/captan programme. The overhead mist applications gave control only when the scab incidence was light. Repeated applications of dinocap emulsion (0.025% a.i.), included in the fungicide programme in 1971, gave as good control of the active stages of fruit tree red spider mite, Panonychus ulmi, when applied by the overhead methods as by conventional spraying, but application of the benomyl programme gave poor control. Mobile overhead spraying of small intensive apple trees is a promising method but needs further development before becoming fully acceptable.     

Pest and disease control with low doses of pesticides in low and ultralow volumes applied to intensive apple trees

In 3 year field experiments on the development of more economical methods for pest and disease control on intensively planted dessert apple trees, low dose applications of one-tenth of the normal quantities of pesticide in one-hundredth, one-tenth and one-fifth of the normal volumes were compared with conventional high volume spraying at 2250 litres/ha. An experimental tractor-mounted mist blower, a motorised knapsack mist blower and a fan-assisted disc sprayer were each used to apply the pesticides in 225, 45 and 22.5 litres of water/ha. Control of the apple-grass aphid, Rhopalosiphum insertum, obtained by low dose spraying of demeton-S-methyl (8 g a.i./ha) combined with azinphos-methyl (37 g a.i./ha) in 225 and 22.5 litres/ha in 1971 and of fenitrothion (70 g a.i./ha) in 225, 45 and 22.5 litres/ha in 1972 and 1973 was almost equal to that obtained by the conventional high volume method. Low dose applications of benomyl fungicide programmes gave poor control of apple scab, Venturia inaequalis in 1971 when the disease incidence on the fruit was very high at 73%, but in 1972 and 1973, when it was moderately high at 42–45%, control was almost equal to that given by the conventional high volume method. Under these conditions all the low dose methods gave better control with benomyl than with dodine/captan programmes.     

Residual effects of fungicidal spray programmes on apple trees

Spraying programmes for apple scab and mildew control sometimes had residual effects for one or even two years. Thus, benomyl (0.025% a.i.) and pyridinitril (0.035% a.i.) drastically reduced the subsequent incidence of cankers caused by Nectria galligena on young wood. Apple scab fruit infection, caused by Venturia inaequalis, was also less on trees on which benomyl had been used in the previous season. In the bark of such trees, toxic residues equivalent to 1 to 4 μg benomyl/g fresh wt. were detected by bioassay 7 months after spraying.     

Implementing wood ants in biocontrol: Suppression of apple scab and reduced aphid tending

BACKGROUND

Ants can become efficient biocontrol agents in plantation crops as they prey on pest insects and may inhibit plant pathogens by excreting broad-spectrum antibiotics. However, ants also provide a disservice by augmenting attended honeydew producing homopterans. This disservice may be avoided by offering ants artificial sugar as an alternative to honeydew. Here we tested the effect of artificial sugar feeding on aphid abundance in an apple plot with wood ants (Formica polyctena, Förster), and tested the effect of ant presence on apple scab (Venturia inaequalis, Cooke) disease incidence.

RESULTS

Over a 2-year period, sugar feeding eliminated ant-attended aphid populations on the apple trees. Furthermore, scab symptoms on both leaves and apples were reduced considerably on ant trees compared to control trees without ants. The presence of ants on the trees reduced leaf scab infections by 34%, whereas spot numbers on fruits were reduced by between 53 and 81%, depending on apple variety. In addition, the spots were 56% smaller.

CONCLUSION

This shows that problems with wood ant-attended homopterans can be solved and that ants can control both insect pests and plant pathogens. We therefore propose wood ants as a new effective biocontrol agent suitable for implementation in apple orchards and possibly other plantation crops. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

A during-infection spray strategy using sulphur compounds,copper, silicon and a new formulation of potassium bicarbonate for primary scab control in organic apple production

In a field experiment conducted over two growing seasons, the effectiveness and phytotoxicity of inorganic fungicides such as sulphur, lime sulphur, copper, silicon and Armicarb (a new formulation of potassium bicarbonate) was compared with water for the control of primary apple scab infections in Belgium on high, medium and low scab-susceptible cultivars (cvs ‘Pinova’, ‘Pirouette’ and ‘Reinette des Capucins’, respectively). In order to drastically reduce the amount of fungicide applied in the orchard, two approaches were used: (1) a strategy involving spraying during the infection process, before fungal penetration and (2) a tunnel sprayer machine for treatment applications. Under field conditions highly favourable for disease, low rates of elemental sulphur (31.8 and 38.6 kg ha⁻¹ year⁻¹ in 2005 and 2006, respectively) combined with low rates of copper (2.1 kg ha⁻¹ year⁻¹ in both years) provided the best scab control and reduced scab severity on the fruits of cv. ‘Pinova’ by 97 and 98% compared with water control in 2005 and 2006, respectively. Lime sulphur was much more effective than wettable sulphur and appeared to be efficient at temperatures below 10°C, but its effectiveness against apple scab decreased if the treatments were applied 12–24 h later than in the ‘during-infection’ spray strategy. Armicarb used alone significantly reduced apple scab severity on the leaves and fruits of the three cultivars compared with the water control. Its effectiveness was as good as wettable sulphur applied using the same timing and dosage. Silicon reduced apple scab on fruits very slightly, but not on leaves. The amounts of wettable sulphur, lime sulphur, copper, silicon and potassium bicarbonate used in this experiment to control apple scab were not phytotoxic, did not increase fruit russet, did increase the yield of each cultivar and did not affect summer density of the beneficial Typhlodromus pyri. The potential and limitations of ‘during-infection’ spraying as a protection strategy against apple scab in organic farming are discussed.     

苹果黑星病在辽宁省的分布及其发生规律

苹果黑星病是辽宁省植物检疫对象。目前主要分布于小苹果栽植区及大、小苹果混栽区,已接近辽宁南部的大苹果主产区。经自然感病和人工接种证明,大、小苹果上的黑星病菌可以交互侵染,目前一些主栽的大苹果品种均能感染此病。辽宁地区苹果黑星病的初次侵染来源是落地越冬病叶上于翌春产生的子囊孢子。分生孢子不能越冬成活。苹果枝条及芽鳞不带菌。黑星病菌的两种孢子随气流传播,使病害逐步扩大蔓延。经过6年的观察,苹果黑星病发生始期早晚及发病轻重,与早春和夏季的降水量多少成正相关。田间药剂防治试验结果,以托布津、乙磷铝、多菌灵、特克多等药剂防治效果良好。     

Selection and orchard testing of antagonists suppressing conidial production by the apple scab pathogen <Emphasis Type="Italic">Venturia inaequalis</Emphasis>

Apple scab caused by Venturia inaequalis is a major disease in apple production. Epidemics in spring are initiated by ascospores produced on overwintering leaves whereas epidemics during summer are driven by conidia produced on apple leaves by biotrophic mycelium. Fungal colonisers of sporulating colonies of V. inaequalis were isolated and their potential to reduce the production of conidia of V. inaequalis was evaluated on apple seedlings under controlled conditions. The four most effective isolates of the 63 screened isolates were tested subsequently under Dutch orchard conditions in 2006. Repeated applications of conidial suspensions of Cladosporium cladosporioides H39 resulted in an average reduction of conidial production by V. inaequalis of approximately 40%. In 2007, applications of conidial suspensions of C. cladosporioides H39 reduced conidial production by V. inaequalis by 69% on August 6 and by 51% on August 16, but no effect was found on August 20. However, viability of available conidia of C. cladosporioides H39 was low at the end of the experiment. Epiphytic and endophytic colonisation by Cladosporium spp. of leaves treated during the experiment with C. cladosporioides H39 was significantly higher than on control leaves sampled 6 weeks after the last application. It is concluded that C. cladosporioides H39 has promising potential as a biological control agent for apple scab control. More information is needed on the effect of C. cladosporioides H39 on apple scab epidemics as well as on mass production, formulation and shelf life of conidia of the antagonist.     

The natural control of the apple-grass aphid,Rhopalosiphum insertum,with remarks on the control of apple aphids in The Netherlands in general

In this paper the apple-grass aphid is stated to be the only aphid in the Netherlands that regularly hibernates in large quantities in commercial apple orchards. The possible reasons for this are discussed. Abiotic factors, especially rain, hail, wind and ice formation in early spring, are by far the most important in drastically reducing the numbers of fundatrices. Of the biotic factors, ladybird beetles in spring may be important. The apple-grass aphid parasite,Monoctonus cerasi, may reach high peaks of parasitism during some periods in the season; in comparison with abiotic factors, however, its effect does not seem to be very important. The life history of the parasite seems to be well adapted to that of its host. It is suggested that the winter wash against apple aphids might be omitted, with eventual application of a spring spray in certain circumstances. In most cases this spray will only be necessary if the rosy apple aphid is present. Samenvatting In deze publikatie wordt er de nadruk op gelegd dat de appel-grasluis,Rhopalosiphum insertum (Wlk.), de enige bladluis is die in appelboomgaarden die in produktie zijn regelmatig in groot aantal als ei overwintert. Hiervoor wordt een aantal redenen opgegeben, die samenhangen met verschillen in de levenswijze ten opzichte van de beide andere belangrijke bladluizen van appel, nl. de roze appelluis,Dysaphis plantaginea (Pass.), en de groene appeltakluis,Aphis pomi Geer. Uit Fig. 1, 2 en 3 blijkt, dat zowel de populatiedichtheid van de bladluis als de parasitering door de voornaamste parasiet,Monoctonus cerasi, in de loop van het seizoen vaak belangrijke schommelingen vertonen. De belangrijkste mortaliteitsoorzaken in het voorjaar zijn abiotische factoren zoals regen, wind, hagel en ijsvorming, die de bladluispopulaties in sterke mate kunnen decimeren. Van de biotische zijn hoofdzakelijk enkele soorten lieveheersbeestjes (Coccinellidae) van belang. De parasiet veroorzaakt in sommige perioden van het jaar weliswaar hoge parasiteringstoppen, maar haar effect is, vergeleken bij de invloed van de genoemde weersomstandigheden, weinig belangrijk. In verband met het besprokene lijkt een winterbespuiting tegen bladluizen op appel in het algemeen overbodig. Zo nodig kan in het voorjaar nog een bespuiting worden toegepast. Dit zal in het algemeen echter alleen noodzakelijk zijn als ook de roze appelluis optreedt, die door het vervormen van de vruchten veel schadelijker is dan de appel-grasluis.     

The effect of three irrigation practices on phytophthora crown and root rot of apple trees under field conditions

The effect of microjet, drip, and two durations of sprinkler irrigation systems on phytophthora crown and root rot of apple trees was examined under field conditions. This eight year study indicates that crown and root rot caused byPhytophthora cactorum was most severe where young MM. 106 rootstock trees were watered by microjet irrigation for 2.3 h each day. There was no difference in infection byP. cactorum when trees were irrigated either by drip or sprinkler irrigation systems. The MM.106 apple rootstock trees watered by drip irrigation for 2.6 h each day were least affected by phytophthora crown and root rot.     

Second World Food Congress

Abstract

Wodlly apple aphid Eriosoma lanigerum (Hsm.) is widely distributed in India. It reproduces all year round on apple and crab apple. Alates are produced from July to November and lay nymphs with degenerate mouth parts. The infestation is spread by nursery plants and air currents. The pest is controlled in the nursery either by dip-treatment with fenitrothion (0.025%) or dichlorvos (0.088%) or by soil application of phorate granules (2.5–3.0 g a.i.) during spring. Subterranean populations can be controlled with granules of dimethoate (15 g a.i.), aldicarb (5.0 g a.i.) or carbofuran (3.0 g a.i.). Aerial populations are controlled by autumn sprays of fenitrothion + dichlorvos + demeton-methyl (0.05%), vamidothion (0.025%), phosophamidon (0.035%) or dimethoate (0.03%). Banding of the trunk base with granules has been found useful in reducing reinfestation by checking the first instar nymphs, which migrate between the aerial and subterranean parts. Resistant root stocks of the ‘M.M.’ series are recommended against the pest.     

Effect of spraying techniques on the brown rot of peach fruit,and on black spot,powdery mildew and the two-spotted mite of apple trees

Application by hand-held equipment of the commercially recommended doses of proprietary formulations of captan (9.0 g a. i. per tree), mancozeb (10.8 g a. i. per tree), oxythioquinox (1.1 g a. i. per tree), and cyhexatin (1.8 g a. i. per tree), in spray volumes ranging from 0.225 to 9.0 litres per tree, gave commercial control of the brown rot of peach fruit, and of black spot (apple scab), powdery mildew and the two-spotted mite (Tetranychus urticae) of apple trees. Commercial control was also obtained using a quarter of the recommended doses when applied in 0.225 or 2.25 litres per tree. The residue of oxythioquinox on the leaves, immediately after applying 1.1 g a. i. per tree, doubled as the volume of spray was reduced from 9.0 to 2.25 litres per tree, and increased further when the volume was reduced to 0.225 litres per tree. It is suggested that some of the oxythioquinox ran off the trees at the higher volumes, and that less run-off at lower volumes resulted in higher chemical residues.     

苏云金杆菌乳剂防治二代棉铃虫保护天敌控制伏蚜的研究

在二代棉铃虫Heliothis armigera卵高峰期,一般年份用200倍,大发生年份用100倍苏云金杆菌(B.t.)乳剂喷雾防治效果达75%以上,可将虫口密度压低到经济损失允许水平以下。防治后调查生防田主要捕食性昆虫天敌比化防田高3倍左右,对伏蚜有较好的控制作用。伏蚜高峰期主要捕食性天敌与伏蚜之比,维持在1:200以上水平,可将防治伏蚜时间推迟10—15天,减少防治1—2次。     

Effect of several insecticides on pomegranate aphid,Aphis punicae (Passerini) (Homoptera: Aphididae) and its predators under field conditions

The pomegranate aphid, Aphis punicae (Passerini) (Homoptera: Aphididae) is one of the most important pests in Egypt on pomegranate trees. The study presented in this paper was conducted from 2012 to 2013 to compare the efficiency and selectivity of neonicotinoids (acetamiprid, imidacloprid, thiamethoxam and dinotefuran), organophosphate (malathion) and carbamate (pirimicarb) insecticides against pomegranate aphid and the associated predators, Coccinella undecimpunctata Linnaeus, Chrysoperla carnea (Stephens) and Syrphus corolla Fabricius. These insecticides significantly reduced the pomegranate aphid population by an average of between 70.6 and 90.7%. The effects persisted for up to 15 days after the end of treatment. The greatest control of A. punicae was achieved by thiamethoxam > acetamiprid > imidacloprid > pirimicarb > dinotefuran > malathion. Acetamiprid, imidacloprid, thiamethoxam, malathion and pirimicarb were harmful to predators and the observed reduction ranged from 75.4 to 100% and dinotefuran was moderately harmful to lacewings with an average reduction about 64.4%. These results suggested that the neonicotinoid insecticides can be considered as promising candidates for controlling the pomegranate aphid as, although they do have harmful to moderately harmful effects on predators, they are significantly less toxic to these beneficial organisms than malathion and pirimicarb.     

Concepts and methods in biological control of diseases in apple orchards1

The project ‘Promotion of Biological Methods in Apple Growing’ which started in Switzerland in 1985 concentrates on the control of Venturia inaequalis (scab) and Podosphaera leucotricha (powdery mildew). The project considers the selection of suitable cultivars resistant or only slightly susceptible to fungal diseases and the assessment of tolerable economic loss. It also includes curative treatments with sterol-synthesis-inhibiting fungicides, according to scab infection periods, as well as applications of plant extracts (proposed by the Institute of Biological Husbandry) and suspensions of antagonists or their culture filtrates as plant-protecting agents. Screening experiments on apple seedlings showed that root extracts of Rumex obtusifolium significantly reduced powdery mildew infections under greenhouse conditions. In field experiments treatments with R. obtusifolium extracts at intervals of 7–10 days were less effective. Saponin-containing extracts of different plants gave satisfying control of scab on seedlings in the growth chamber but were not very effective in the field. Applications of spore suspensions and culture filtrates of the phyllosphere fungi Chaetomium spp. reduced scab and mildew infections on apple seedlings to some extent. It was found that in the last 2 years even primary infections of P. leucotricha were severely parasitized by Ampelomyces quisqualis. Preliminary studies showed that the lack of efficacy of this biocontrol system is due to the delayed spread of the hyperparasite.     

Control of purple nutsedge (Cyperus rotundus) in cotton with benfuresate

The herbicide benfuresate applied preplanting to cotton (Gossypium hirsutum L.) fields infested with purple nutsedge (Cyperus rotundus L.) inhibited nutsedge growth for several weeks and was found selective for cotton. The best nutsedge control was achieved when the herbicide was mechanically incorporated following a preplant broadcast or band application which was activated by a sprinkler irrigation. The rate of benfuresate needed for effective and selective nutsedge control in cotton ranged from 0.80 to 1.60 kg/ha, the higher rates necessary in soils with higher clay and organic matter contents.     

Management of strawberry anthracnose by choice of irrigation system,mulching material and host resistance

We studied, by means of field experiments, the combined effects of irrigation system, mulching material and genetic resistance on the incidence of strawberry anthracnose caused by Colletotrichum acutatum. All trials involved artificial inoculation with fruits colonized by the pathogen. One experiment examined the effects of drip irrigation, overhead sprinkler irrigation, and localized low-pressure tape irrigation, and the effects of grass (Brachiaria sp.) and plastic (polyethylene) mulches, in a split plot, randomized complete block design with four replicates. Lower disease incidence, indicating lower pathogen dispersal, was verified with low-pressure tape and drip irrigation. Flower blight and fruit rot incidence in drip-irrigated plots was minimal (ca. 2% of the disease levels in the plots otherwise irrigated). Grass mulch reduced flower blight in the sprinkler system (up to 80%), but had no significant effect when disease levels were already low due to use of other irrigation systems. A second experiment compared the effects of grass mulch, pine (Pinus elliotti) mulch, and plastic mulch with overhead sprinkler irrigation on strawberry cultivars partially resistant (‘Dover’) and susceptible (‘Campinas’) to the disease in a factorial completely randomized design (CRD). Both organic mulches reduced flower blight and diseased fruit incidence by up to 76% compared to the plastic mulch treatment, especially in the early stages of the epidemics. ‘Dover’ had 70% lower incidence of flower blight than ‘Campinas’, and the effects of organic mulches were more pronounced in ‘Campinas’. A third experiment, with all three irrigation systems combined with inoculated and non-inoculated plots, estimated yield effects due to disease and irrigation system. All plots were covered with plastic mulch in a CRD with six treatments. This experiment clearly confirmed the higher flower blight and fruit rot incidences when sprinkler irrigation was used. In inoculated treatments, fruit yield was significantly reduced in tape-irrigated plots, and more so in sprinkler-irrigated plots. In drip-irrigated plots yield was reduced by only 1%. Overall, our results confirm the importance of cultural and genetic factors as valuable means of strawberry anthracnose management. Adoption of localized irrigation systems, the use of organic mulches and choice of a partially resistant cultivar significantly reduced disease levels in field plots. The importance of water splash for C. acutatum dispersal and its dependency on the soil mulch characteristics are the likely causes for the results observed.     

植保无人飞机低容量喷洒15%苯甲·吡唑酯微乳剂对3种苹果叶部病害的防效评价

为明确纳米杀菌剂的减量增效作用,本研究采用2种喷施方法,以水敏纸为雾滴沉积指示剂, 分析植保无人飞机和背负式电动喷雾器喷施15%苯甲·吡唑酯微乳剂(ME)和25%苯甲·吡唑酯悬浮剂(SC)两种不同剂型杀菌剂的雾滴密度及雾滴覆盖率,调查并计算苹果病叶率、病情指数、防治效果和综合效益。结果表明,植保无人飞机飞行高度影响雾滴密度和覆盖率,纳米农药15%苯甲·吡唑酯ME的雾滴密度和覆盖率与25%苯甲·吡唑酯悬浮剂(SC)的雾滴密度和覆盖率有差异。各杀菌剂处理对苹果锈病的防效最好,防治效果均在97%以上,对苹果黑星病的防治效果次之,末次药后15 d的防治效果均在90%以上,对苹果斑点落叶病有效,末次药后15 d的防治效果均在50%以上。植保无人飞机喷施纳米杀菌剂15%苯甲·吡唑酯ME在防治成本、时效性和节能上均明显优于背负式电动喷雾器。因此,采用植保无人飞机喷施纳米杀菌剂15%苯甲·吡唑酯ME可有效防治苹果黑星病和苹果锈病,同时实现杀菌剂减量,综合效益较高。     

The importance of forecasting and warning systems in implementation of integrated pest management in apple orchards in Turkey*

Integrated Pest Management (IPM) has been widely implemented in apple orchards in various regions of Turkey. Between 1995 and 1999, in Central Anatolia and the Aegean Region, apple scab (Venturia inequalis) and codling moth (Cydia pomonella) were key pests, and implementation of pest control was based on forecasting and warning systems. During the project, orchards in which IPM was implemented and in which farmers applied conventional practices were compared. In nine provinces in which IPM projects were carried out in 1999, the damage due to codling moth was 0–1.3% in IPM orchards while it was 0.4–21.8% in nearby non‐IPM orchards. It is clear that damage did not reach the acceptable threshold level of 2% in any of the IPM orchards, while damage was much higher than the threshold in conventionally‐farmed orchards. The number of fungicide applications against apple scab decreased to 5–6 applications from 10–15 applications in the Eğirdir district of the Isparta Province in 1996 as a result of IPM implementation. No insecticides were applied against codling moth in IPM orchards in the Nigde Province in 1998 and 1999 because population levels of the pest were low and under the economic threshold. Apple producers received training and 1200 producers from Central Anatolia became experts in IPM for their own orchards, learning to make appropriate decisions about pest control. The Apple IPM Guideline was prepared and disseminated. In Turkey modern equipment for forecasting and warning systems was employed and, in the last decade, forecasting and warning networks have been improved. Computer‐based systems have increased the speed and accuracy of forecasting as well as decreasing its costs. A computerized national forecasting network in apple orchards now transmits data from the field to system headquarters automatically. The national forecasting network has been expanded and covered 12 208 800 apple trees in 34 provinces in 2006, using 115 electronic forecasting and warning stations.     

Etiology and control of powdery scab of potato in a semi-arid region of Israel

Powdery scab of potato, incited bySpongospora subterranea var.subterranea (Walk.) Lagerh., was recently identified in Israel. Experiments were conducted to determine the role of tuber-borne inoculum in inciting the disease, and to eradicate tuber- and soilborne inoculum. Dipping for 2 min in a mixture of 0.75% ai. pentachloronitrobenzene and 0.03% a.i. organic mercury was found to be highly effective in controlling tuber-borne inoculum. Soil fumigation with methyl bromide or treatment with metham-sodium in irrigation water provided good control of soilborne inoculum.     

The use of fomesafen for pre-emergence weed control in cotton

The herbicide fomesafen was found to be selective in preplanting and pre-emergence treatments in cotton (Gossypium hirsutum L.). It was effective due to residual soil activity in controlling some of the most troublesome weeds in cotton fields,i.e., pigweed (Amaranthus spp.), black nightshade (Solarium nigrum L.), velvetleaf (Abutilon theophrasti Medik.) and cocklebur (Xanthium spp.). The best soil activity of fomesafen was achieved from pre-emergence or preplanting applications which were activated when the soil was wetted by rain or sprinkler irrigation, but the herbicide caused damage to the crop’s foliage if rain fell just after the cotton emergence. The most effective and safest method for applying fomesafen in cotton fields was preplanting followed by mechanical incorporation to a depth of 10 cm. Combinations of fomesafen with trifluralin were effective and completed the spectrum of controlled weeds in cotton, including annual grasses, common purslane (Portulaca oleracea L.) and field bindweed (Convolvulus arvensis L.).