Grasshopper Damage Research Articles

EVALUATION OF RICE GENOTYPE AGAINST LEAF FOLDER, CASE WORM AND GRASSHOPPER DESECRATION UNDER FIELD CONDITION

The research on varietal screening of rice against leaf folder, caseworm and grasshopper damage was conducted during 2019 in Rampur, Chitwan to study the host plant resistant of different varieties of rice under field condition. The experiment was laid out in RCBD with three replications and seven treatments namely i) Makawanpur -1 ii) Mansuli iii) Radha-4 iv) Ramdhan v) Sabitri vi) Sama Mansuli sub-1 and vii) sukkha-3. The experiment revealed that lowest population of leaf folder, caseworm and grasshopper was recorded in variety Radha-4 followed by Ramdhan. The experiment showed the yield loss was significantly lower in Radha-4 followed by Sabitri and Ramdhan due to leaf folder, caseworm and grasshopper. So Radha-4 and sabitri would be good option in rice production for reducing insect pest damage.

Indirect effects of nutrients in organic and conventional paddy field soils on the rice grasshopper, Oxya japonica (Orthoptera: Acrididae), mediated by rice plant nutrients

Current agricultural technology depends on synthetic fertilizers and enhances the growth of herbivorous insect populations. Some organic farming uses bio-based nutrients instead and is considered the most promising way to mitigate the negative effects of conventional farming. The rice grasshopper Oxya japonica (Thunberg) (Orthoptera: Acrididae) is the most abundant herbivore in both conventional and organic fields in northern Japan. This study investigated the effects of soil nutrients associated with conventional versus organic farming on rice plant quality,and the growth and performance of O. japonica in paddy fields at Sakata, Yamagata Prefecture. A laboratory experiment was also conducted to understand the effects, as mediated by host plant quality, of organic and conventional soil nutrients on the growth and feeding (as measured by the leaf area consumed) of O. japonica. Nymphs of O. japonica that fed on nitrogen-rich, carbon-poor plants cultivated in conventional soil grew and developed faster than those feeding on organic plants. The rice plants in conventional fields had greater biomasses, suggesting that they were more likely to tolerate grasshopper damage. These results support the importance of soil nutrient management as a factor that influences plant–herbivore interactions.

Impact of grasshopper feeding on selected cultivars of cruciferous oilseed crops

With the trend towards crop diversification, there has been a gradual increase in production of crucifer oilseed crops (canola and mustard) in the Prairie Ecozone of western Canada. Developments in germplasm of Brassica spp. and Sinapis alba L. have resulted in cultivars with improved drought resistance, making them more acceptable for production in arid regions of the prairies. This, in turn, has resulted in increased overlap in areas of grasshopper infestation and oilseed production. Grasshoppers are the most chronic insect pests of annual crops in the Prairie Ecozone. The primary threat to production of annual crops arises from migration of the hatchling populations into cropland from roadsides, headlands and field margins at the beginning of the growing season. As a result, grasshopper damage is most acute at the early stages of crop growth.In this study, the impact of early season grasshopper feeding on canola and mustard crops was quantified in field studies, 1996 to 1998. Immatures of Melanoplus sanguinipes (the lesser migratory grasshopper) were allowed to damage eight Brassicaceae cultivars and breeding lines of four species: Brassica juncea Czern (‘AC Vulcan’ and ‘J92-223’), B. napus (‘AC Excel’ and ‘Midas’), B. rapa (‘AC Parkland’ and ‘Echo’) and S. alba (‘AC Pennant’ and ‘Ochre’). The overall yields of defoliated plants were 27.8% less than those of control plants (p = 0.0001). Yield reductions were greatest for AC Excel (47%) and least for AC Vulcan (19.6%). The results are discussed in the context of grasshopper management strategies.

Grasshopper (Orthoptera: Acrididae) damage to flowers and pods of lentil ( Lens culinaris L.)

A study was initiated in response to concerns that grasshoppers were becoming an economic issue in lentil crops. The study characterized the type and extent of damage and determined the relationship between grasshopper numbers ( Melanoplus bivittatus Say) in lentil ( Lens culinaris L.) during flowering and yield loss. In commercial fields, grasshopper damage was found on sepals, flowers and both immature and mature pods. Grasshoppers at relatively low population density levels have a major impact on yield of lentil. Populations of 2–3/m 2 damaged up to 23% of the viable pods and 47% of the flowers and immature pods. Field-cage trials along with recent estimates of crop yields, crop price and control costs were used to estimate an economic threshold. The relationship was linear ( F=42.98; P=0.0001). The fitted linear relationship ( y=247.5−5.2 x; R 2=0.71) estimates an average yield loss of approximately 2% for every one grasshopper/m 2. This information is pertinent to an economic evaluation of management strategies against grasshoppers in lentil.

Importance of Grasshopper Defoliation Period on Southwestern Blue Grama-Dominated Rangeland

Most economic assessments of grasshopper damage are based on how much plant tissue insects consume or destroy without considering factors that influence the ability of individual plants and communities to respond to damage. Properly grazed perennial warm-season grasses, such as blue grama [Bouteloua gracilis (H.B.K.) Lag. ex Griffiths], can withstand considerable defoliation. We investigated the effects of heavy defoliation on blue grama rangeland by caging bigheaded grasshoppers [Aulocara elliotti (Thomas)] during early, mid, and late growing seasons for 2 years in southwestern New Mexico. Peak standing crop (PSC) of blue grama defoliated in the early-season was the same as that in cages protected from defoliation both years. However, peak standing crop of blue grama was reduced in cages defoliated during the mid and late growing seasons in both years. The importance of midseason feeding was compounded by significant changes in relative proportions of various herbage categories in the standing crop. Forbs and sedges made up a larger percentage of the total forage production at PSC after mid-season defoliation during both years. On rangelands where blue grama is dominant, even very high densities of early-season grasshoppers may not influence herbage production. Substantial declines in grasshopper densities observed before summer rains during both years should influence management decisions. Unless early-season forb production is an important part of a ranch management plan, the damage potential of early- and mid-season grasshopper species may be lower on southwestern rangelands where mid- to late-summer precipitation patterns occur than reported in the literature for other areas of the western United States due to later maturation of warm-season grasses. In most years, depending upon precipitation patterns, there may be adequate growth following heavy early-season herbivory to feed both livestock and grasshoppers.

Control of Grasshopper Spp. in Seedling Winter Wheat Using a Systemic Seed Treatment, 1995

Abstract Gaucho 480 (imidacloprid) was applied as a seed treatment at 2, 3, and 4 oz/cwt rates and evaluated for control of grasshopper damage in winter wheat. Additionally, all seed was treated with RTU-Vitavax-Thiram at 6oz/cwt. Gaucho treated seed was planted at 55 lb/acre rate in a RCB design with 4 row plots (12 inch spacing) by 35 ft on 15 Sep at the MSU-Central Agricultural Research Center, Moccasin, MT. Treatments were replicated 6 times. Grasshopper populations in the area adjacent to the test area were estimated to be 10 grasshoppers per ft2. Number of plants and number of grasshopper-damaged plants per row ft were recorded and data was expressed as percent damaged plants. Data were analyzed by analysis of variance and means separated using Duncan’s Multiple Range Test.

Hybrid Populus in reclamation

ABSTRACT Hybrid Populus was grown from cuttings for 5 years on two reclamation sites in southern Illinois. Plantings were made in two years and establishment varied with weather and site conditions including grasshopper damage. There were few later losses and growth was rapid with early canopy closure. Harvested trees re-grew rapidly. The root depth reached within 3 years, opening up substantial root channels, was nearly equivalent to that of 8-year old trees. Best performance was found on strongly-compacted, poorly-drained clay soils contrary to cited reports for Populus. Hybrid Populus has great potential in reclamation for quickly shading out competing herbaceous cover, mitigating soil compaction problems, and growing well with soil flooding that limits growth of most kinds of trees.

The Effect of Perennial Grasses on Growth, Development and Survival of Grasshopper Nymphs (Orthoptera: Acrididae): Implications for Population Management in Roadsides

Growth, development and mortality of nymphs of Melanoplus sanguinipes (Fabr.) fed diets of one of 12 species or cultivars of perennial grasses were monitored over a 3-week period in early summer, 1991 and 1992. Mean dry weight of grasshoppers was significantly higher (P < 0.05) on Western wheat grass (cv. S-8580) than any other grass, and lowest on smooth brome grass (cv. Carlton and Signal). Development of grasshoppers was significantly more rapid (P < 0.05) when feeding on Western wheat grass (cv. S-8580) and Intermediate wheat grass (cv. S-9051) than any other grass. Smooth brome grass had the greatest negative impact on grasshopper development. Mortality among grasshoppers fed these grasses was not significantly different over the 21 days. Analysis of historical grasshopper abundance survey data showed that mean grasshopper densities in 15 of 18 years (1975-1992) were significantly lower (P <0.05) in roadsides containing brome grass and alfalfa than in roadsides containing a high proportion of weeds. This relationship also held true for cropland that was adjacent to these respective roadsides. In 11 of 18 years of the adult grasshopper survey, mean grasshopper density was significantly higher (P <0.05) in crops that were next to weedy roadsides compared to those next to brome grass/alfalfa. In no year was the inverse true, that is, grasshopper density in brome grass/alfalfa was never significantly higher than in weedy roadsides. Records from the annual grasshopper abundance survey (1975-1992) indicate that about 30% of roadsides in Saskatchewan are weedy. Grain producers may be able to reduce grasshopper damage if these roadsides were seeded to brome grass or brome grass/alfalfa mixture [

The Pest Status of Zonocerus Elegans (Thunberg) (Orthoptera: Acridoidea) in Kilosa District in Tanzania with some Suggestions on Control Strategies

The elegant grasshopper, Zonocerus elegans Thunberg, occurs in large numbers in Kilosa district during the dry season June to January and attacks a wide range of wild and crop plants. Its impact as a pest of crop plants becomes more noticeable from the middle of the dry season when the hoppers are well advanced and the only alternative food available are vegetables in backyard gardens and river valleys. The grasshopper damage continues throughout the vuli (short) rains until the end of the oviposition period in January, thus limiting the production of green vegetables in the district. A study on the biology and ecology of the pest in Kilosa district with emphasis on short term control strategies was started in 1987. Spot spraying with insecticides to kill the early instars was found to be effective, but area-wide implementation was necessary to prevent re-invasion of cleared areas.

Differential feeding by grasshoppers and levels of foliar diseases in various cultivars of spring cereals

Sixty-four cultivars and strains of cereals were evaluated under field conditions for differential feeding by grasshoppers, (Orthoptera:: Acrididae) and for their resistance to foliar disease. Grasshoppers actively fed on all triticale and durum wheat lines, on 11 of 12 bread wheat lines, and on 11 of 24 barley lines. Both the incidence and severity of foliar disease were high in all cereals. There was no correlation between grasshopper damage and resistance to foliar disease ( r+ −0·059) in the barley but a positive trend appeared in wheat lines (bread r= +0·487; durum r= +0·295). The data suggest that present trends in breeding disease-resistant cereal cultivars will not introduce increased susceptibility to grasshopper damage.

19. The design and use of living snow fences in North America

Living snow fences are rows of trees and shrubs planted to control snow along land transportation routes, and which have the potential to (1) provide snow control, (2) enhance wildlife habitat, (3) provide winter livestock protection, (4) furnish environmental beautification and (5) offer long-term economic benefits. Disadvantages include the difficulty of establishment on some sites, the length of time to reach serviceable height, the high initial cost as compared to some structures, the degree of maintenance during the establishment period and the amount of land required. Primary features of living snow fence location and design include (1) distance from road, (2) length, (3) species, (4) number of rows, (5) spacing and (6) wildlife components. Each of these is discussed at length. Maintenance, which is the effort required to obtain satisfactory survival and growth, can present a number of problems in arid regions with limited precipitation. In such areas, issues which must be dealt with include irrigation, weed control, and protection from grazing livestock, big game animals, rodents, hot, dry winds and grasshopper damage. Solutions to these problems are discussed.

Neem Products for Protecting Field Cassava From Grasshopper Damage

Three neem products—an emulsifiable concentrate of neem oil (NOEC), neem kernel water extract (NKWE) and neem leaf water extract (NLWE)—were applied on field cassava for protection against damage by the grasshopper, Zonocerus variegatus (L.). Three conventional insecticides viz. lindane 0.3%, Cypermethrin 0.006% and monocrotophos 0.24% were also compared. All the neem products protected cassava for varying periods. Efficacies of NOEC and NKWE were superior to insecticides. From the results, neem products recommended to check the grasshopper damage were as follows: NOEC 0.5–2% to be applied every 8 days, NOEC 3–4% to be applied every 10 days, NKWE 7–10% to be applied every 12 days, NLWE 50% to be applied every 6 days.

Weeding as a means of reducing the population of grasshopper pests and damage on pearl millet [ Pennisetum americanum (L.) K. Schum] in northern Nigeria

A millet farm was divided into five treatment plots of three replicates. The population of the grasshoppers was assessed by flushing and the percentage leaf damage on the millet was estimated by visual grading of the defoliated area. Weeding discouraged oviposition and reduced the vegetative shelter and the population of the grasshoppers. The unweeded plots had high levels of defoliation and low grain yield of millet relative to the weeded plots. Oedaleus spp were the most numerous grasshoppers and probably caused the greatest damage on pearl millet. The common weeds on the farm were Brachiaria xantholeuca, Cenchrus biflorus, Ipomoea vagans and Mitracarpus scaber .

A Model Simulating Grasshopper Damage to Wheat Planted in Infested Stubble

A Model Simulating Grasshopper Damage to Wheat Planted in Infested Stubble

EFFECTS OF ACUTE SIMULATED AND ACUTE GRASSHOPPER (ORTHOPTERA: ACRIDIDAE) DAMAGE ON GROWTH RATES AND YIELD OF SPRING WHEAT (TRITICUM AESTIVUM)

AbstractStudies showed that the type of damage, the timing of damage with the phenological stage of the crop, and the amount of available soil moisture influenced the growth response of spring wheat to acute levels of grasshopper damage and acute levels of artificial damage. Ground-level cutting of plants resulted in the greatest reduction in plant biomass and crop yield, while grasshopper damage and artificial stripping of leaf material did not result in as severe a reduction in either biomass or yield.Damaged plants were not able to recover lost biomass when damage occurred any later than the early stages of tillering despite observed relative growth rates which were higher than control plants. The greatest degree of recovery occurred in study sites with the greatest amount of available soil moisture.The most detrimental effect of damage on yield was the reduction of heads per plant and kernel weight. In most cases differences in the number of seeds per head between damaged and control plants were not evident.

AERIAL PHOTOGRAPHY FOR DETECTION AND ASSESSMENT OF GRASSHOPPER (ORTHOPTERA: ACRIDIDAE) DAMAGE TO SMALL GRAIN CROPS IN SASKATCHEWAN

AbstractAerial colour infra-red photographs were used to detect grasshopper damage to cereal grains, determine extent of damage, estimate crop yield, and identify crops. The detection and identification of grasshopper damage was facilitated by the development of a dichotomous key which differentiates grasshopper damage from other crop anomalies. Crop types and yield were determined from correlations between the optical density of the photographs and the biomass of standing crops.Cost of an aerial survey was estimated at $0.02 per hectare as compared with ground survey cost of $0.20 per hectare. Information provided by an aerial survey of damage has the potential to assist grain growers, extension personnel, and researchers in evaluating the influence of grasshoppers on grain production

Control of Tobacco Flea Beetles, Aphids, and Grasshoppers on Burley Tobacco, 1979

Abstract Twenty-two insecticide treatments were evaluated. Soil insecticides were applied and incorporated prior to transplanting on June 6. Foliar sprays were applied with 2.5 gal compressed air sprayers at 30 gal/acre. Portable CO2 tanks supplied a constant sprayer tank pressure of 30 psi. Foliar applications were made on a 14-day schedule for a total of five beginning June 25. Plots were 20 ft × 3 rows spaced 40 inches apart; plants were spaced 14 inches apart. Four randomized complete blocks were separated from each other by 5 ft alleys. Flea beetle damage was evaluated as feeding holes/10 leaves; counts were made on the fifth leaf (of width greater than 2 in) from the top of the plant. Aphid ratings ranged from 0 (no evident infestation) to 5 (heavy infestation with necrosis of lower leaf bases). Grasshopper damage ratings ranged from 0 (no damage) to 3 (heavy damage to at least 3/4 of the leaves). Insect feeding and damage evaluations were based on 40 leaf samples.

Control of Tobacco Flea Beetles, Aphids, and Grasshoppers on Burley Tobacco, 1979

Abstract Twenty-two insecticide treatments were evaluated. Soil insecticides were applied and incorporated prior to transplanting on June 6. Foliar sprays were applied with 2.5 gal compressed air sprayers at 30 gal/acre. Portable CO2 tanks supplied a constant sprayer tank pressure of 30 psi. Foliar applications were made on a 14-day schedule for a total of five beginning June 25. Plots were 20 ft × 3 rows spaced 40 inches apart; plants were spaced 14 inches apart. Four randomized complete blocks were separated from each other by 5 ft alleys. Flea beetle damage was evaluated as feeding holes/10 leaves; counts were made on the fifth leaf (of width greater than 2 in) from the top of the plant. Aphid ratings ranged from 0 (no evident infestation) to 5 (heavy infestation with necrosis of lower leaf bases). Grasshopper damage ratings ranged from 0 (no damage) to 3 (heavy damage to at least 3/4 of the leaves). Insect feeding and damage evaluations were based on 40 leaf samples.

A QUANTITATIVE EVALUATION OF GRASSHOPPER (ORTHOPTERA: ACRIDIDAE) DAMAGE AND ITS EFFECT ON SPRING WHEAT

AbstractStudies were carried out to investigate the growth response of normal and defoliated spring wheat. Plant growth is expressed by the von Bertalanffy (1957) growth equation modified to allow for declining growth potential with age. Grasshopper damage was assessed by comparison with artificial defoliation and results indicated a simple linear relationship between grasshopper food consumption and defoliation damage. On the basis of this relationship it indicated that grasshoppers feeding on wheat waste 6.2 times as much foliage as they actually consume. Damage to foliage is translated into an effect on grain yield by an allometric relationship between total plant weight and yield. A simulation model indicating the time course of plant biomass provides realistic estimates except in the case of acute defoliation.

Barley proteinase inhibitors: A possible role in grasshopper control?

Young growing barley seedlings contain trypsin and chymotrypsin proteinase inhibitors in their leaf juices. The amount of chymotrypsin inhibitor varies greatly while trypsin inhibitor content is nearly the same in all varieties tested. Compana (CI5438) barley has much more total inhibitor than does Trebi (CI 936), Titan (CI 7055), Horn (CI 926), Hiproly (CI 3947) and Hiproly Normal (CI 4362). The distribution of inhibitors in different barley varieties correlates with the severity of grasshopper damage observed by other workers. Barley leaves could not be induced to accumulate proteinase inhibitors after excision and incubation, wounding, or absorption of crude “proteinase inhibitor inducing factor” preparations. Grasshopper damage experiments as related to proteinase inhibitor should be done in the field using yield as the correlative factor.