Carrot Plots Research Articles

The damage the Family Psilidae to agriculture (Insecta: Diptera)

Biology of the carrot fly Psila rosae (Fabricius, 1794) was described by the Danish zoologist Fabricius as early as the 18th century (Fabricius, 1794). The flies overwinter mainly as pupae in the soil near their host plants, in mild winters also as larvae in the host plant roots or in harvest residues. Depending on the temperature, the first generation of carrot flies hatches from mid/late April and reaches a peak in May. Little is known about the spread of adult flies and their migration to current carrot plots, but vegetation elements presumably play an important role in orientation and protection against dehydration. The aim of the mini review is to study on the biology, behavior and damage caused by the carrot fly (Diptera: Psilidae). The aim of this study is to report the characteristics of the Family Psilidae. For this, a bibliographic survey of Scoliidae was carried out in the years to 2022. Only complete articles published in scientific journals and expanded abstracts presented in national and international scientific events were considered.

Interactions of Undescribed Drilus Beetle Larvae with Pestiferous Limicolaria flammea (Gastropoda: Achatinidae): Are There Prospects for Biocontrol?

The garden snail, Limicolaria flammea is a seasonal pest of several horticultural crops in most of the agroecological areas in Nigeria. The level of damage to crops is especially enormous in the South because of its ability to feed on different crops and the timing of abundance, the early rain season, which usually coincide with onset of rain-fed crop production which expose seedlings and grown-up crop plants to serious damage. In this study, we recorded occurrence data of Limicolaria flammea in okra, carrot, sweet potato, lettuce and maize within a single multi-crop organic farm in order to understand its food preference. Activities of the predatory beetle larvae, Drilus sp was observed within the environment. The appearance of the larvae was described and its interaction with L. flammea was studied to generate some data on the proportions of snail mortality caused by Drilus sp and other mortality factors that naturally regulate the population dynamics of L. flammea within the environment. There was no statistically significant difference in the average number of snails recorded in the different cropping fields [F (4,15) =1.369, P=0.291]. The activities of Drilus larvae against L. flammea was higher in okra and carrot plots as snail mortality due to the larvae attack were significantly higher compared to what was recorded in other crop plots [F (4, 30) =3.998, P=0.01].The Drilus larvae predate on L. flammea by appertural entry, biting through the soft tissues around the mantle to gain entrance and moult into instar larvae within the snail shell in 15-20 days, leaving its exuviae behind in the shell in all the specimens observed (n=40). The Drilus species being reported in this study is morphologically distinct from other described species in available literature. The study suggested that the Drilus species is less known and there are potentials that the species could be useful in inundative biocontrol approaches for the management of pestiferous gastropod populations.

Growth and Yield of Corn, Carrot and Onion Treated With Rock Phosphate Organic Fertilizer Grown in Standoff Soil Southern Alberta, Canada

An experiment was performed in Standoff, Southern Alberta to investigate resource cheap rock phosphate organic fertilizer application to corn, carrot and onion plots. The objective of the study was to ascertain effectiveness of rock phosphate organic fertilizer to support growth and yield of corn, carrot and onion crops grown in Southern Alberta. The varying levels of rock phosphate at 50 P kg/ha for Low P, 100 P kg/ha for High P and control were applied to corn, carrot and onion plots. These treatments were replicated three times, resulting into nine plants per crop. Agronomical parameters collected were subjected to analysis of variance using Duncan Multiple Range Test for separation of means. Result of the experiment indicated that Low P and High P favoured corn height and number of leaves but did not support other parameters measured due to inadequate rock phosphate applied. It was observed that rock phosphate influenced residual level of P after harvest of corn, carrot and onion. Onion plots had the highest P left in the soil than corn and carrot plots. This studies showed potential of rock phosphate in crop production, if apply in adequate amount and availability of soil moisture, as well as high residual P in the soil after harvest.

Field Validation of the Effect of Soil Fumigation of Ethanedinitrile (EDN) on the Mortality of Meloidogyne hapla and Carrot Yield Parameters

With the increasing importance of soilborne plant pest nematodes and the relatively recent phase-out of methyl bromide as a key soil fumigant, there is an urgent need for new fumigants with good nematicidal properties. Ethanedinitrile (EDN) is a promising fumigant and preparation because of its physical, agrochemical, and nematicidal properties. However, its efficacy against nematode pests of different crops under field conditions has not been fully validated and understood. Therefore, the aim of our study was to evaluate the effect of two concentrations of EDN on the survival of northern root-knot nematodes (Meloidogynehapla) and on carrot yield and quality under field conditions. The evaluation was performed using naturally infested carrot plots, and EDN application to the soil was followed by covering the treated area with film. A high biological effect was observed for both EDN concentrations tested, with even the lower dose (30 g·m−2) being sufficient for M. hapla suppression. Positive effects of EDN application—likely due to EDN partial conversion into biologically available nitrogen in soil—on carrot root weight, in comparison with the untreated control, were also observed.

Potential of Adding Constructed Wetland/Fishpond to Waste Stabilization Ponds to Improve Helminths Removal in Morogoro Municipality, Tanzania

A study was conducted to establish the potential of constructed wetlands in Morogoro Urban District, Tanzania, to remove helminths from wastewater. The standard wastewater treatment regime was failing to effect reliable removal of helminth eggs and larvae from six wastewater stabilization ponds. An alternative wastewater treatment regime for the ponds, coupled with a constructed wetland and a fishpond, was devised. Water, soil, and vegetable samples were tested for the presence of helminth larvae and eggs in a time series design over one growing season. From March to August 2014, experimental plots of carrots and Swiss chard were irrigated with wastewater that had been treated by the alternative wastewater treatment regime. It was found that the alternative wastewater treatment regime coupled with the constructed wetland and fishpond appeared to remove helminths completely. No helminths were found in the wastewater after it passed through the alternative system, and none were found in the market-ready carrots and chard. Numbers of helminth larvae and eggs showed evidence of seasonality, which is potentially useful knowledge for farmers in order to avoid helminth infection: almost all larvae were found at the end of the hot dry season. Monsoon rains followed and washed the helminth larvae and eggs away and none were found at the end of the season. Keywords : wastewater stabilization ponds, constructed wetlands, helminth removal, hookworm, sewage treatment

CHARACTERIZATION OF ISOLATES OF ALTERNARIA AND FUSARIUM FOUND IN CARROT FROM DIFFERENT ECOLOGICAL AND GEOGRAPHIC ZONES

Selection of infected material for research was carried out in experimental carrot plots at GNU VNIIO (Moscow region), Voronezh OOS (Voronezh oblast), Baraccudas OOS (Rostov region) and Israel. The first year plants of carrot, the roots, were used for the study. There are many scientific papers cited where many different methods of artificial infection of plants with fungal disease pathogens were given to control the stability of carrot genotypes in various phases of plant development. One of the ways to lead the purposed breeding program for resistance is the extraction of pathogens isolates and the method of fast assessment on the basis of determining the aggressiveness of new strains and their use in breeding work. This article presents a method of inoculation of cut-discs of root. A great advantage of the method is in its efficiency and the current results can be obtained within 2 weeks from the moment of infection. As a result, the work on the isolation of fungi from carrot plants, the pure culture collection of strains: Alternaria radicina and Fusarium avenaceum was obtained. The characteristics and morphology description of colonies of isolates of RR. Alternaria and Fusarium found in carrot plants taken from different ecological and geographical zones were given. The most aggressive isolates of the following ecological and geographical zones as Alternaria at Moscow and Rostov regions, Fusarium at Voronezh and Moscow regions were revealed. These isolates will be used as standards of aggressiveness for the test of newly isolated strains regarded as inoculum to conduct immunological experiments in carrot breeding for resistance to Fusarium and Alternaria.

English

The existing literature for the recommendation of fertilizers and diagnosis of the nutritional status of the carrot crop is outdated because it contemplates productivities lower than those currently obtained. The objective of this research was to characterize the nutritional demand of the carrot crop by estimating the dry matter content of the roots, the coefficient of biological utilization of the nutrients and the harvest index of dry matter and of the mineral nutrients, in order to indicate fertilizers according to the desired productivity for winter and summer cultivations. We sampled 210 carrot plots located in the Alto Paranaiba region, Minas Gerais, Brazil, during 2012 and 2013. We determined the content of dry matter of the roots, the coefficient of biological utilization of the nutrients in the roots and leaves and the harvest index of dry matter and nutrients in the crop. Data were grouped in two groups of cultivations: Winter and summer. The harvest index of dry matter and of nutrients was bigger for the winter cultivars. Regardless of the growing season, the N, P, K, Mg and B were retained in greater amounts in the roots. Phosphorus had the highest harvest index, and the Cu, the lowest. The differences were insignificant in the nutritional demand of N, P, Ca, S, B, Cu and Zn between winter and summer cultivars for the average productivity obtained in each season. In the summer cultivars, the carrot accumulates greater amounts of Fe and lower of K, Mg and Mn when compared to winter. The modeling of the nutritional demand of the carrot crop can be carried out depending on the desired productivity and growing season. Key words: Nutrients balance, Daucus carota, nutritional demand, nutrients recommendation.

The impact of plant associations onMacrosteles quadrilineatusmanagement in carrots

AbstractHabitat diversification can influence the interactions of insects with plants and this can be used in agroecosystems for the management of pest populations. Plant diversification can be achieved through planting crops, such as trap crops, or by adjusting weed management. Aster leafhopper,Macrosteles quadrilineatusForbes (Hemiptera: Cicadellidae), is a polyphagous species that uses cereals, vegetables, and weeds as host plants. The influence of weeds onM. quadrilineatusabundance was investigated experimentally in carrot [Daucus carotaL. cv. Canada (Apiaceae)] field plots by adjusting the level of management of two groups of weeds (broadleaf and grass) and by comparing it to weed‐free plots. The preference ofM. quadrilineatusfor different cereal and weed species relative to carrots was tested in choice test assays. Habitat context influenced the abundance ofM. quadrilineatusin the field experiments. The presence of border crops such as oat, rye, barley, wheat, and triticale did not significantly attract or repel this insect to carrot plots compared to the no‐border treatment. However, spelt‐bordered plots had 42% fewerM. quadrilineatusthan three treatments, triticale, wheat, and barley, that had the highest insect abundance. The type of weed management affectedM. quadrilineatusabundance in carrot plots, but not the frequency of herbicide application. Plots that had carrot growing with broadleaf‐weeds had about 59% fewerM. quadrilineatuscompared with those growing with crabgrass or carrot alone. In the greenhouse choice tests, grasses (e.g., cereals) attracted and broadleaf‐weeds repelledM. quadrilineatusrelative to carrots. In summary, carrot growers may be able to manage this pest by reducing the interaction of cereal cover crops with carrots and eliminating grassy weeds in commercial production fields.

Patterns of spread of Carrot virus Y in carrot plantings and validation of control measures

AbstractPatterns of spread of Carrot virus Y (CarVY) were examined in carrot plantings in Western Australia into which naturally occurring aphid vectors spread the virus from external infection sources. Within three field trials, CarVY ‘infector’ plants were introduced between or at different distances from carrot plantings. There was a marked decline in CarVY incidence over distance from adjacent introduced infection sources. Clusters of infected plants that enlarged and coalesced were concentrated next to such sources but, later, isolated, expanding clusters formed further away. With a small external virus source, initial spread into the edge of a planting was less extensive than with a larger source. When 15‐m‐wide fallow areas separated a CarVY source from carrot plots, spread was much slower than when the separation was only 1 m; it was also slower upwind than downwind of this source. The data collected help validate the inclusion of isolation and ‘safe’ planting distances, intervening fallow, planting upwind, prompt removal of virus sources, avoidance of side‐by‐side plantings and manipulation of planting date within an integrated disease management strategy for CarVY in carrots.

A simple method – based on the carrot fly – for studying the movement of pest insects

AbstractThis paper describes a method for studying the neighbourhood (dispersal) movement of pest insects that overcomes the major problems associated with release/recapture experiments. The method has been developed using the carrot fly, Psila rosae (Fab.) (Diptera: Psilidae), as the experimental insect. It involves building up a large population of insects in an area free of other host plants, and then, as the insects disperse in the spring, monitoring the fall‐off in numbers of insects with increasing distance. Estimates of the fall‐off in numbers of the carrot fly were obtained by using sticky traps to monitor changes in fly numbers in 11 small plots of carrots drilled 130–1300 m away from the site at which the flies emerged (emergence site) in the spring. A strong linear relationship (r2 = 0.96) was obtained between the log10 numbers of flies caught in each plot and the log10 distance the plot was from the emergence site. Few flies were caught more than 1 km from the emergence site. A linear relationship (r2 = 0.86) was also obtained between the date when 50% of the flies were caught in each plot and the distance the plot was from the emergence site. The date of 50% capture was delayed by 1 day for each 100 m the given plot was away from the emergence site. This suggests that when carrot flies move to find new crops, the population moves about 100 m day−1. About one million flies would have to be released in conventional release/recapture experiments to obtain data as robust as those collected using the current method. The major breakthrough of this method is that dispersal can be estimated for an insect species that, although a major pest of field crops of carrots and parsnips, is exceptionally difficult to rear, even in relatively small numbers, under controlled‐environment conditions.

Records of Airborne Mycocentrospora acerina Conidia in and Near Carrot Plots

The occurrence of Mycocentrospora acerina conidia in the air, in or close to carrot plots, was examined by the use of volumetric spore traps at three locations, in connection with crop-rotation experiments in Norway. The traps were operated during the late summers of 1985-1987 and in 1995. At two locations, M. acerina conidia were recorded on a limited number of days. Only a few conidia were trapped outside the plot. At one of the locations, no conidia were observed. The highest conidial record, 47 conida per m3 air, was observed inside the carrot plot, during 1 h in September 1985 at one location. Only one or two conida were trapped on most of the other days. The conidial records in relation to climatic parameters are discussed. Aerial spread of M. acerina conidia appears to be insignificant in the climatic conditions of Norway.

Yield, vitamin and mineral contents of organically and conventionally grown carrots and cabbage

Research was conducted for 3 years in different plot areas of a Pugwash sandy loam near Truro, N.S. Five replicates of two treatments (organic and conventional) were established annually for carrots ( Daucus carota L. cv. ‘Cellobunch’) and cabbages ( Brassica oleracea L. var capitata cv. ‘Lennox’). The addition of pesticides, lime and NPK fertilizer to the conventional plots followed soil test and provincial recommendations; lime, composted manure and insect control applications to the organic plots were according to the guidelines of the Organic Crop Improvement Association Inc. The compost was analyzed for total N and applied to provide 170 kg N ha −1 for carrots and 300 kg N ha −1 for cabbages, which assumed 50% availability of N. In addition to marketable yields, carrot leaves and roots and cabbage sections were digested and analyzed for 12 macro- and micronutrients. Vitamins C and E and α- and β-carotene of mature crops were evaluated by high performance liquid chromatography; in 2 of the 3 years, vitamin C was also analyzed up to 24 weeks after harvest. Soil samples were also taken at harvest, extracted with Mehlich-3 or 2 M KCl solution and analyzed for essential nutrients and available N. Analysis of the 3 years of data showed that the yield and vitamin content of the carrots and cabbages were not affected by treatments. Five elements in carrot roots (N, S, Mn, Cu, B) and two elements in carrot leaves (S, Na) were influenced by treatments ( P < 0.11); in cabbages, N, Mn and Zn were affected. The treatments did not affect the Mehlich-3 extractable soil nutrients in the carrot plots, whereas only Mehlich-3 Cu and the NH 4-N and NO 3-N contents of the soil were affected in the cabbage plots. In a comparison of soil and plant elements, the Mehlich-3 Ca and Mg in the carrot plots and the Mehlich-3 P, K and Zn in the cabbage plots were significantly correlated with both the edible and/or leaf tissue contents of these elements.

Density dependence of Anaphes sordidatus (Hymenoptera: Mymaridae) parasitism on eggs of Listronotus oregonensis (Coleoptera: Curculionidae).

Listronotus oregonensis (LeConte) (Coleoptera: Curculionidae) oviposits in carrot leaves and the larvae feed in carrot roots. Its eggs are parasitized by Anaphes sordidatus (Girault) (Hymenoptera: Mymaridae) throughout its oviposition period. This parasitoid is the major biotic mortality factor for L. oregonensis. Parasitism by A. sordidatus was studied for three years in sequentially sown plots of carrots, Daucus carota var. sativa. Over the scason, significantly fewer L. oregonensis eggs were oviposited in later sown carrots than in earlier sown carrots because oviposition started later in late sown plots of carrots. A positive temporal density-dependent relationship was observed each year between parasitism rates and host densities. This positive density dependence occurred in early and mid-summer for earlysown carrots where host density reached 1-2 host eggs per plant but disappeared in late summer when host density decreased while parasitism remained high. Latesown carrots had low host egg density (0.2 host egg per plant) and contributed little to the total number of eggs. In these late sown plots, parasitism increased rapidly to over 80% but no density dependence was observed. Spatially, few statistically significant regressions were found but all indicated a positive spatial density-dependence. Most non-significant regressions occurred because the range of egg density was too small between plots for a given date.

The effect of the annual use of some pesticides on soil microorganisms, pesticide residues in soil and carrot yields

AbstractThe study deals with the effect of common, annually‐used pesticides on soil microorganisms, pesticide residues in soil, and carrot (Daucus carota) yields in Central Finland. Linuron residues in carrot roots were also analysed. Thiram+lindane and dimethoate were applied from 1973–1981 at the commercially recommended doses on experimental plots of carrots, linuron was applied at twice the recommended rate from 1973–1979 and at the normal rate thereafter and in addition TCA was applied in 1978. Maleic hydrazide was used in the years 1973–1976, and glyphosate after 1977. The numbers of different soil microorganisms, their activities and the pesticide residues were studied from autumn 1978 to 1981. The pesticide treatments reduced the growth of soil algae but increased the total number of microorganisms and the number of aerobic spore‐forming bacteria. Linuron residues in the soil were 0.9–2.8 mg kg−1 in the growing season and 1.2–1.7 mg kg−1 in the autumn, 3 months after application. The residues of glyphosate in the soil were 0.7 mg kg−1 in the autumn, 41 days after the treatment, and had declined to a level of about 0.2 mg kg−1 by the following summer. In the pesticide‐treated plots the carrot yield was only 20–60% of the yield in the hand‐weeded plots. The herbicide programme controlled most of the annual weeds but not couchgrass Elymus repens and milk sow‐thistle Sonchus arvensis.

Seasonal Occurrence of Carrot Rust Fly (Diptera: Psilidae) Adults in Ontario and Its Relation to Cumulative Degree-Days

The seasonal occurrence of adult carrot rust flies, Psila rosae (F.), in the Holland Marsh, near Bradford, Ontario, was determined from 1972 to 1980 with the aid of emergence cages and sticky yellow traps located in insecticide-free plots of carrots. Dates of first emergence of the overwintered generation (OWG) ranged from 16 May to 1 June, and those of the first generation (1G) from 22 July to 3 August. Indices based on mean cumulative degree-days (DD) to observed seasonal events over 4 to 7 years permitted prediction of first emergence or first trap catch within 1 to 1.8 days of observed dates. The indices (with mean error of prediction) were: first emergence of OWG adults, 236 DD (air) above 5°C after 1 April (1 day) or 220 DD above 3°C (soil, 5 cm) after 1 April (1.5 days); first trap catch of OWG adults, 258 DD (air) above 5°C after 1 March (1.5 days); first emergence of 1G adults, 971 DD above 3°C (soil) after date of first emergence of OWG adults (1.5 days) or 1,050 DD (air) between 5 and 20°C after 1 March (1.8 days); and first 1G trap catch, 1,150 DD above 5°C after 1 March (1.6 days).

Influence of some field‐applied nematicides on microflora and mineral nutrients in an organic soil1

Abstract Nematicide formulations Bunema, Telone II, Telone C 17, Temik, Nemacur, Vydate, Nematak and Furadan were applied at 1.5 to 2X of normal doses to 1.8 × 3 m field plots of carrots (Daucus carota L. Var. sativa DC cv Goldpak). The plots were on an organic soil heavily infested with Meloidogyne hapla Chitwood, the northern root knot nematode which parasitizes carrots. Application of Temik did not cause prolonged or marked changes in microbial population of the soil. The addition of Nematak increased the fungal population for up to 30 days while its effect on bacterial plus actinomycetal population was ambivalent and transitory. Both fungi and bacteria + actinomycetes groups were increased by Nemacur for 0–9 days but the bacterial and actinomycetal population was decreased at 30 days after application. Vydate and the carbamate nematicides Furadan and Bunema generally increased the microbial population, particularly the fungi. The chlorinated aliphatic hydrocarbons Telone II and Tel one C17 caused marked increments in fungal, bacterial and actinomycetal populations 0 to 28 days after application. Available plant nutrient (NH+ 4, NO‐ 3, PO— 4, K+) levels and soil pH were unaffected by the nematicide applications except for an increase in NH+ 4 level caused by Bunema, Telone II and Telone C17, and a temporary decrease in NO‐ 3 concentration where Telone II and Telone C17 were added.

Yield and Secondary Root Growth of Carrots as Influenced by Tillage System, Cultivation, and Irrigation1

Abstract There were no significant yield differences among tillage systems of carrots (Daucus carota L. cv. Danvers 126) planted into a rye mulch, soybean stubble, and conventionally tilled plots. Secondary root growth of carrot was greater in soybean than either rye or conventionally-tilled carrot plots. Irrigation decreased secondary root growth in conventional tilled and rye mulch plots, but not in the soybean stubble.

Aster Yellows Control in Head Lettuce and Carrots in Prince Edward Island1

Weekly applications of DDT, 1 lb toxicant/acre, plus malathion, 1.25 lb, resulted in a significantly lower incidence of aster yellows in head lettuce, a virus disease transmitted in nature largely by the six-spotted leafhopper, Macrosteles fascifrons (Stål). Twice-weekly applications were more effective than weekly applications. Granular phorate applied to the soil with the seed at planting time at 1 lb toxicant/acre was as effective as either Di-Syston® (O,O-diethyl 5-[2- (ethylthio) ethyl] phosphorodithioate) or E.I. 43064 (2- (diethoxyphosphinothioylimino)-1-3-dithiolane) at 2 lb. Control of lettuce and carrot yellows with phorate was equal to that obtained with regular sprays of malathion or carbaryl. E.I. 47031 (2- (diethoxyphosphinylimine) 1-3-dithiolane) was not effective in reducing the incidence of lettuce yellows, although some control of carrot yellows was evident. Spraying barriers of sweet corn plants that completely surrounded lettuce and carrot plots, rather than the lettuce and carrots, was not effective in reducing the incidence of lettuce or carrot yellows.