GIS based pest-weather model to predict the incidence of Girdle beetle (Oberiopsis brevis) in Soybean crop

Girdle beetle (Oberiopsis brevis) is an important insect of soybean that can cause up to 42.2% yield loss in severe infestation during flowering stage. The infestation of girdle beetle is prevailed by congenial environmental conditions, which leads girdle beetle to be the severe pest of soybean. The present study assesses the relevant weather variables that can cause the peak infestation. Crop Pest Surveillance and Advisory Project (CROPSAP) survey data of girdle beetle incidence were analyzed with weather variables using correlation and regression techniques. The girdle beetle infestation had significantly positive correlation with relative humidity of current and 2nd lag week (RH0, RH-2); and with rainfall of 2nd lag week (RF-2) but significantly negative correlation with maximum temperature of 1st lag week (TMax-1). The multiple regression technique was used to develop the forewarning models for three zones (Vidarbha, Madhya Maharashtra and Marathwada zones) and overall Maharashtra, the developed models could explain 80.30%, 94.62%, 73.56% and 79.56% variation in girdle beetle infestation, respectively. The congenial conditions for the peak infestation of girdle beetle on soybean have been worked out and validated, which were TMax0, RH0, RF0, RH-1, RF-1, TMax-2, and RF-2 ranged between 28.6-31.6 ºC, 85.2- 91.8 %, 31.8-119.2 mm, 86.3-92.6 %, 38.1-76.4 mm, 27.7-30.8ºC, and 23.3-60.7 mm, respectively. The insect forewarning would be useful in devising the integrated management strategies for protecting the crop from insect in the incidence region.

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Competitive ability of soybean cultivars with horseweed (Conyza bonariensis)

Planta Daninha ◽

10.1590/s0100-83582013000300006 ◽

2013 ◽

Vol 31 (3) ◽

pp. 543-550 ◽

Cited By ~ 12

Author(s):

M.M. Trezzi ◽

A.A. Balbinot Jr. ◽

G. Benin ◽

F. Debastiani ◽

F. Patel ◽

...

Keyword(s):

Grain Yield ◽

Competitive Ability ◽

Yield Loss ◽

Integrated Management ◽

Block Design ◽

Management Strategies ◽

Soybean Cultivars ◽

Conyza Bonariensis ◽

Randomized Complete Block Design ◽

Plant Characteristics

The existence of large areas infested with populations of Conyza spp. resistant to glyphosate in Brazil demands appropriate and integrated management strategies. This experiment aimed to identify soybean cultivars with greater competitive ability with horseweed plants and to determine plant characteristics associated with this ability. The experiment was arranged in a randomized complete block design with split plots. Seven soybean cultivars (CD 225 RR, BRS 232, CD 226 RR, NK 7054 RR, BMX Apollo RR, BRS 245 RR and BRS 255 RR) were allocated in the plots, and two interference situations (absence and 13.3 plants of Conyza m-2, transplanted seven days before soybean planting) in the subplots. The average yield loss due to competition with horseweed was 25%. Cultivar CD 226 RR showed no significant grain yield loss due to competition, compared to the control without infestation, but showed the lowest average grain yield. The BRS 232 genotype showed loss of grain yield of only 14%, and presented positive plant height and leaf mass at 20 DAE, as well as dry matter of stems+branches in all evaluations, features related to its higher performance and greater ability to withstand competition with horseweed plants.

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Fusarium Head Blight Epidemics in Soft Red Winter Wheat Fields in Georgia from 2018 to 2019

Plant Health Progress ◽

10.1094/php-08-21-0111-rs ◽

2021 ◽

Author(s):

Bikash Ghimire ◽

James Buck ◽

Mohamed Mergoum ◽

Alfredo D. Martinez-Espinoza

Keyword(s):

Winter Wheat ◽

Fusarium Head Blight ◽

Integrated Management ◽

Management Strategies ◽

The United States ◽

Kernel Weight ◽

Head Blight ◽

Weather Variables ◽

Soft Red Winter Wheat ◽

Red Winter Wheat

Fusarium head blight (FHB) epidemics on wheat have caused significant yield and economic penalties in the United States since the early 1990s. This report documents FHB epidemics on soft red winter wheat in Georgia in 2018 and 2019. Forty-four wheat fields across 23 counties were assessed for FHB incidence (2019 only), Fusarium-damaged kernel, deoxynivalenol (DON) contamination, and thousand kernel weight. Higher levels of FHB were observed in 2019 compared to 2018. A significant correlation was observed between DON and 7-day pre-anthesis weather variables in 2019. FHB parameters were significantly correlated to post-anthesis weather variables at 10-day in both years and at 20 and 30-day in 2018 suggesting that post-anthesis rather than pre-anthesis weather had a greater impact on FHB in our study. The combination of hours of conducive temperature and relative humidity post-anthesis was consistently correlated with all FHB parameters in both years and could be the best predictor of FHB epidemics. FHB has emerged as the leading threat for soft red winter wheat production in Georgia. Planting moderately resistant wheat cultivars along with in-season management including proper fungicide application, by closely monitoring the national FHB forecasting system, would be the best integrated management strategies for Georgian wheat growers.

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Effect of Row Spacing and Seeding Rate on Russian Thistle (Salsola tragus) in Spring Barley and Spring Wheat

Plants ◽

10.3390/plants10010126 ◽

2021 ◽

Vol 10 (1) ◽

pp. 126

Author(s):

Judit Barroso ◽

Nicholas G. Genna

Keyword(s):

Seed Production ◽

Crop Yield ◽

Spring Wheat ◽

Plant Biomass ◽

Integrated Management ◽

Spring Barley ◽

Management Strategies ◽

Crop Productivity ◽

Row Spacing ◽

Seeding Rate

Russian thistle (Salsola tragus L.) is a persistent post-harvest issue in the Pacific Northwest (PNW). Farmers need more integrated management strategies to control it. Russian thistle emergence, mortality, plant biomass, seed production, and crop yield were evaluated in spring wheat and spring barley planted in 18- or 36-cm row spacing and seeded at 73 or 140 kg ha−1 in Pendleton and Moro, Oregon, during 2018 and 2019. Russian thistle emergence was lower and mortality was higher in spring barley than in spring wheat. However, little to no effect of row spacing or seeding rate was observed on Russian thistle emergence or mortality. Russian thistle seed production and plant biomass followed crop productivity; higher crop yield produced higher Russian thistle biomass and seed production and lower crop yield produced lower weed biomass and seed production. Crop yield with Russian thistle pressure was improved in 2018 with 18-cm rows or by seeding at 140 kg ha−1 while no effect was observed in 2019. Increasing seeding rates or planting spring crops in narrow rows may be effective at increasing yield in low rainfall years of the PNW, such as in 2018. No effect may be observed in years with higher rainfall than normal, such as in 2019.

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Biological control agents in the integrated nematode management of potato in Egypt

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-020-00325-x ◽

2020 ◽

Vol 30 (1) ◽

Cited By ~ 1

Author(s):

Mahfouz M. M. Abd-Elgawad

Keyword(s):

Biological Control ◽

Crop Yields ◽

Integrated Management ◽

Management Strategies ◽

Economic Value ◽

Potato Production ◽

Parasitic Nematodes ◽

Main Body ◽

Biological Control Agents ◽

Economic Significance

Abstract Background Potato represents Egypt’s largest vegetable export crop. Many plant-parasitic nematodes (PPNs) are globally inflicting damage to potato plants. In Egypt, their economic significance considerably varies according to PPN distribution, population levels, and pathogenicity. Main body This review article highlights the biology, ecology, and economic value of the PPN control viewpoint. The integration of biological control agents (BCAs), as sound and safe potato production practice, with other phytosanitary measures to manage PPNs is presented for sustainable agriculture. A few cases of BCA integration with such other options as synergistic/additive PPN management measures to upgrade crop yields are reviewed. Yet, various attributes of BCAs should better be grasped so that they can fit in at the emerging and/or existing integrated management strategies of potato pests. Conclusion A few inexpensive biocontrol products, for PPNs control on potato, versus their corresponding costly chemical nematicides are gathered and listed for consideration. Hence, raising awareness of farmers for making these biologicals familiar and easy to use will promote their wider application while offering safe and increased potato yield.

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Factors affecting Cyperus difformis seed germination and seedling emergence

Planta Daninha ◽

10.1590/s0100-83582013000400008 ◽

2013 ◽

Vol 31 (4) ◽

pp. 823-832 ◽

Cited By ~ 7

Author(s):

A. Derakhshan ◽

J. Gherekhloo

Keyword(s):

Seed Germination ◽

Integrated Management ◽

Germination Rate ◽

Seedling Emergence ◽

Management Strategies ◽

Soil Surface ◽

Weed Species ◽

Factors Affecting ◽

Cyperus Difformis ◽

Emergence Patterns

Specific knowledge about the dormancy, germination, and emergence patterns of weed species aids the development of integrated management strategies. Laboratory studies were conducted to determine the effect of several environmental factors on seed germination and seedling emergence of Cyperus difformis. Germination of freshly harvested seeds was inhibited by darkness; however, when seeds were subsequently transferred to complete light they germinated readily. Our results showed that 2 wk of cold stratification overcome the light requirement for germination. Seeds of C. difformis were able to germinate over a broad range of temperatures (25/15, 30/20, 35/25, and 40/30 ºC day/night). The response of germination rate to temperature was described as a non-linear function. Based on model outputs, the base, the optimum and the ceiling temperatures were estimated as 14.81, 37.72 and 45 ºC, respectively. A temperature of 120 ºC for a 5 min was required to inhibit 50% of maximum germination. The osmotic potential and salinity required for 50% inhibition of maximum germination were -0.47 MPa and 135.57 mM, respectively. High percentage of seed germination (89%) was observed at pH=6 and decreased to 12% at alkaline medium (pH 9) pH. Seeds sown on the soil surface gave the greatest percentage of seedling emergence, and no seedlings emerged from seeds buried in soil at depths of 1 cm.

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Puccinia triticina (wheat brown rust).

10.1079/cpc.45859.20210100344 ◽

2021 ◽

Author(s):

Henriette Goyeau

Keyword(s):

Leaf Rust ◽

Yield Loss ◽

Genetic Resistance ◽

Puccinia Triticina ◽

Multiple Point ◽

Yield Losses ◽

Flowering Stage ◽

Crop Losses ◽

Pathogen Virulence ◽

Cropping Season

Abstract Leaf rust seldom kills wheat, but it is capable of causing 35-50% yield loss in endemic areas on susceptible cultivars, where severity levels of 25-40% are reached at the tillering stage and 100% at the flowering stage. The disease causes more damage worldwide than other wheat rusts. Quarantine is of no relevance as leaf rust is of worldwide occurrence and virulences spread freely between nations and zones. Crop losses are dependent on the genetic resistance of each cultivar, pathogen virulence and environmental conditions. Losses caused by leaf rust particularly originate from reductions of the wheat photosynthetic area. Infected plants normally produce a lower number of tillers, lower amounts of grains per head and smaller grains. The earlier the epidemic in the cropping season, the higher the yield losses. Mathematical models for estimating disease severity and crop losses have been developed based on multiple-point disease recording at different physiological stages of the plant (Burleigh et al., 1972; Eversmeyer and Kramer, 1998, 2000).

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Initial growth and development of southern sandbur based on thermal units

Planta Daninha ◽

10.1590/s0100-83582014000200011 ◽

2014 ◽

Vol 32 (2) ◽

pp. 335-343 ◽

Cited By ~ 5

Author(s):

E.C.R. Machado ◽

R.S.O. Lima ◽

A.P.P. Silva ◽

B.S. Marques ◽

M.F. Gonçalves ◽

...

Keyword(s):

Growth And Development ◽

Dry Matter ◽

Integrated Management ◽

Base Temperature ◽

Initial Growth ◽

Agricultural Systems ◽

Degree Days ◽

Flowering Stage ◽

Weed Biology ◽

Best Fit

Availability of basic information on weed biology is an essential tool for designing integrated management programs for agricultural systems. Thus, this study was carried out in order to calculate the base temperature (Tb) of southern sandbur (Cenchrus echinatus), as well as fit the initial growth and development of the species to accumulated thermal units (growing degree days - GDD). For that purpose, experimental populations were sown six times in summer/autumn conditions (decreasing photoperiod) and six times in winter/spring condition (increasing photoperiod). Southern sandbur phenological evaluations were carried out, on alternate days, and total dry matter was measured when plants reached the flowering stage. All the growth and development fits were performed based on thermal units by assessing five base temperatures, as well as the absence of it. Southern sandbur development was best fit with Tb = 12 ºC, with equation y = 0,0993x, where y is the scale of phenological stage and x is the GDD. On average, flowering was reached at 518 GDD. Southern sandbur phenology may be predicted by using mathematical models based on accumulated thermal units, adopting Tb = 12 ºC. However, other environmental variables may also interfere with species development, particularly photoperiod.

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Spider mites of agricultural importance in China, with focus on species composition during the last decade (2008–2017)

Systematic and Applied Acarology ◽

10.11158/saa.23.11.1 ◽

2018 ◽

Vol 23 (11) ◽

pp. 2087 ◽

Cited By ~ 6

Author(s):

Peng-Yu Jin ◽

Lu Tian ◽

Lei Chen ◽

Xiao-Yue Hong

Keyword(s):

Species Composition ◽

Dominant Species ◽

Integrated Management ◽

Management Strategies ◽

Spider Mites ◽

Management Program ◽

Pest Species ◽

Panonychus Citri ◽

Important Species ◽

River Region

Understanding pest species composition and their geographic distribution of important spider mites is fundamental and indispensable to establish an integrated pest management program. From a long-term survey during 2008–2017 in mainland China, we found that Tetranychus truncatus was the most frequently sampled Tetranychus spider mite (48.5%), followed by T. pueraricola (21.2%), T. kanzawai (12.5%), T. urticae (red) (5.7%) and T. urticae (green) (4.5%). Among them, T. truncatus was the major mite pest in the north of China. T. kanzawai was the dominant species in the Middle and Lower Reaches of the Yangtze River Region and T. pueraricola was the most important species in the southwest region. Other common and serious pests include Amphitetranychus viennensis (6.8%) and Panonychus citri (3.8%). This pattern was largely different from that in 2002–2004, when T. urticae (green and red) was believed to be the most serious mite pest. The factors involved in the change of species composition are not clear and need more exploration. We suggested that the increasing corn planting range may be partly responsible for the conversion of dominant species from other spider mites to T. truncatus. Further research on the mechanisms underlying the change of dominant species will help develop integrated management strategies.

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