Pre-harvest field application of enhanced freshness formulation reduces yield loss in orange

Abstract Background Orange (Citrus sinensis L.) production in Tanzania is constrained by several pre-harvest factors that include pests. Hexanal, sprayed as Enhanced Freshness Formulation (EFF) is a relatively new technology that has been reported to reduce pre-harvest loss in fruits. However, the effects of hexanal on pre-harvest yield loss of orange are not known. We studied the effects of hexanal as EFF on yield losses of three sweet orange cultivars namely, Early Valencia, Jaffa, and Late Valencia. Factorial experiments tested the effects of EFF concentration, variety, and time of EFF application on number of dropped fruit, percentage of non-marketable fruit and incidence of pest damage. Results Results showed significant negative correlation (p < 0.001) between EFF and the percentage of dropped fruit, non-marketable yield, and incidence of pest damage. An increase in hexanal concentration by 1%, is expected to reduce number of dropped fruit by 50, percentage of non-marketable by 35.6, and incidences of pest damage by 36.5% keeping other factors constant. Results also show significant association (p < 0.001) between time of hexanal application and non-marketable yield. Percentage of dropped fruit is expected to increase by 1 for each day away from harvest, keeping other factors constant. Conclusion Pre-harvest application of hexanal as EFF can significantly reduce number of dropped fruits, percentage of non-marketable fruit and incidence of pest damage.

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Effect of Leaf Removal on the Growth And Yield of Okra (Abelmoschus Esculentus) and its Relevance to Leaf Harvesting Patterns and Pest Damage

Experimental Agriculture ◽

10.1017/s0014479700100195 ◽

1988 ◽

Vol 24 (4) ◽

pp. 449-455 ◽

Cited By ~ 1

Author(s):

F. O. Olasantan

Keyword(s):

Yield Loss ◽

Economic Loss ◽

Abelmoschus Esculentus ◽

Growth And Yield ◽

Insect Damage ◽

Leaf Removal ◽

Fresh Leaf ◽

Pest Damage ◽

Young Leaves ◽

Marketable Fruit

SummaryExperiments on okra to determine the economic loss caused by insect damage to the leaves or by harvesting young leaves as a vegetable are described. Leaf harvests at 1-weekly intervals yielded 30-50% more fresh leaf than harvests at 2 or 3-weekly intervals. Removing a quarter of each leaf or single leaves from the upper or lower parts of the plant at 3-weekly intervals did not affect marketable fruit yield, but yield was reduced by about 30% when one young leaf was harvested at 1 or 2-weekly intervals or when two or three leaves were harvested at S-weekly intervals. Removing more than one quarter of each leaf or two or three fully expanded leaves from the lower three-quarters of the plant at 3-weekly intervals also caused up to 40% yield loss.Harvesting single leaves at S-weekly intervals is therefore recommended if okra is to be grown for both leaves and pods. The plant can tolerate at least 25% defoliation, as can happen with insect damage, before any yield loss occurs.F. O. Olasantan: Efecto de la deshojadura sobre el crecimiento y rendimiento del gombo (Abelmoschus esculentus,) y su importancia para modelos de cosecha de hojas y dano causado porplagas.

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Pre-plant Dipping of Strawberry Transplants for Control of Colletotrichum acutatum

HortScience ◽

10.21273/hortsci.41.4.1012a ◽

2006 ◽

Vol 41 (4) ◽

pp. 1012A-1012

Author(s):

Oleg Daugovish ◽

Doug Gubler

Keyword(s):

Fruit Yield ◽

Colletotrichum Acutatum ◽

Yield Reduction ◽

Yield Losses ◽

Marketable Yield ◽

Lesion Development ◽

Strobilurin Fungicides ◽

Air Temperatures ◽

Strawberry Anthracnose ◽

Marketable Fruit

Strawberry anthracnose caused by Colletotrichum acutatum may kill strawberry plants or reduce plant vigor and marketable yield, resulting in multimillion dollar losses to strawberry industry. The fungus is often carried with transplants from nurseries to production fields undetected. The studies in one summer and two winter seasons near Oxnard, Calif., evaluated 30-second pre-plant dipping in ten fungicide solutions or water washing of transplants inoculated with C. acutatum as a means of reducing infection and improving fruit yield. In summer-planted `Baeza,' the pathogen caused severe die-back and reduced marketable fruit yield 89% in inoculated, untreated controls compared to non-inoculated plants while plants dipped in Switch (cyprodynil + fludioxynil) at 0.38 g/L had 33% yield reduction. Other fungicides provided even less protection, resulting in 53% to 89% yield losses. During cooler winter seasons the pathogen remained latent and lesions appeared on `Camarosa' when the day-night air temperatures reached 16 °C or more, 7–14 days after rain. None of the treatments reduced fruit lesion development, however, among plants dipped in strobilurin fungicides only 3% had C. acutatum symptoms (including early die-back) as opposed to 26% in inoculated, untreated controls. Plants dipped in Switch, Quadris (azoxystrobin), or Pristine (pyraclostrobin + boscalid) yielded similar to non-inoculated, untreated controls in 2003 and 10% to 12% more in 2005. These studies showed that strobilurin fungicides did not prevent fruit infection (indicating need for foliar in-season control) but improved marketable yield compared to the inoculated, untreated plants. Temperatures over 16 °C and precipitation may significantly increase disease development.

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Dose Response of Glyphosate and Dicamba on Tomato (Lycopersicon esculentum) Injury

Weed Technology ◽

10.1614/wt-d-11-00073.1 ◽

2012 ◽

Vol 26 (2) ◽

pp. 256-260 ◽

Cited By ~ 19

Author(s):

Greg R. Kruger ◽

William G. Johnson ◽

Douglas J. Doohan ◽

Stephen C. Weller

Keyword(s):

Lycopersicon Esculentum ◽

Dose Response ◽

Yield Loss ◽

Field Studies ◽

Vegetative Stage ◽

Yield Losses ◽

Marketable Yield ◽

Processing Tomato ◽

Commercial Processing ◽

Tomato Cultivars

Field studies were conducted to determine the response of sublethal glyphosate and dicamba doses to processing tomato flowering loss and marketable yield. Dose–response studies for both herbicides were conducted on four commercial processing tomato lines (two different lines within each study) and plants were sprayed at either the vegetative stage or the early bloom stage. Both glyphosate and dicamba caused higher yield losses when sprayed at the early bloom stage. A 25% yield loss was observed with 8.5 and 7.5 g ae ha−1for glyphosate and dicamba, respectively, at the early bloom stage and 43.9 and 11.9 g ae ha−1for glyphosate and dicamba, respectively, at the early vegetative stage. Overall, these tomato cultivars were more sensitive to dicamba than to glyphosate. We conclude that glyphosate and dicamba drift could have serious implications on tomato yields especially if the drift occurs during flowering.

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The impact of cultivar resistance and fungicide treatment on mycotoxin content in grain and yield losses caused by Fusarium head blight in wheat

Czech Journal of Genetics and Plant Breeding ◽

10.17221/93/2009-cjgpb ◽

2010 ◽

Vol 46 (No. 1) ◽

pp. 21-26 ◽

Cited By ~ 10

Author(s):

V. Šíp ◽

J. Chrpová ◽

O. Veškrna ◽

L. Bobková

Keyword(s):

Grain Yield ◽

Fusarium Head Blight ◽

Field Experiments ◽

Yield Loss ◽

Joint Effect ◽

Yield Losses ◽

Cultivar Resistance ◽

Head Blight ◽

Fungicide Treatment ◽

The Impact

Reactions to artificial infection with Fusarium graminearum isolates and a new fungicide Swing Top were studied in nine winter wheat cultivars evaluated in field experiments at two sites for three years for expression of symptoms, deoxynivalenol (DON) content in grain and grain yield. The results demonstrate a pronounced and relatively stable effect of cultivar resistance on reducing head blight, grain yield losses and contamination of grain by the mycotoxin DON. It is advantageous that the moderate level of resistance to Fusarium head blight (FHB) was detected also in two commonly grown Czech cultivars Sakura and Simila. Average fungicide efficacy for DON was 49.5% and 63.9% for a reduction in yield loss, however, it was found highly variable in different years and sites. The joint effect of cultivar resistance and fungicide treatment was 86.5% for DON and even 95.4% for reducing the yield loss. A very high risk was documented for susceptible cultivars and also the effects of medium responsive cultivars were found to be highly variable in different environments and therefore not guaranteeing sufficient protection against FHB under different conditions.

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Modeling the Competitive Effect of Euphorbia dracunculoides and Astragalus sp. in Zero Input Rainfed Chickpea

Planta Daninha ◽

10.1590/s0100-83582018360100021 ◽

2018 ◽

Vol 36 (0) ◽

Author(s):

R.M. IKRAM ◽

A. TANVEER ◽

R. MAQBOOL ◽

M.A. NADEEN

Keyword(s):

Protein Content ◽

Critical Period ◽

Field Experiments ◽

Seed Protein ◽

Yield Loss ◽

Seed Protein Content ◽

Yield Losses ◽

Competition Period ◽

Crop Competition ◽

Weed Removal

ABSTRACT: Brown chickpea (Cicer arietinum L.) is one of the two chickpea types grown in Pakistan and other countries. The critical period for weed removal in a rainfed chickpea system is an important consideration in devising weed management strategies. Field experiments were conducted in the winter season of 2011 and 2012 to determine the extent of yield loss with different periods of weed crop competition. Seven weed crop competition periods (0, 45, 60, 75, 90, 105 and 160 days after sowing - DAS) were used to identify the critical period for weed removal in rainfed chickpea. Experimental plots were naturally infested with Euphorbia dracunculoides and Astragalus sp. in both years. Individual, composite density and dry weights of E. dracunculoides and Astragalussp. increased significantly with an increase in the competition period. However, yield and yield-contributing traits of chickpea significantly decreased with an increase in the competition period. Chickpea seed yield loss was 11-53% in different weed crop competition periods. Euphorbia dracunculoides and Astragalus sp. removed 39.9 and 36.9 kg ha-1 of N, 9.61 and 7.27 kg ha-1 of P and 38.3 and 36.9 kg ha-1 of K, respectively. Season long weed competition (160 days after sowing) resulted in 19.5% seed protein content compared with 24.5% seed protein content in weed-free chickpea. A Logistic equation was fitted to yield data in response to increasing periods of weed crop competition. The critical timing of weed removal at 5 and 10% acceptable yield losses were 26 and 39 DAS, respectively. The observed critical period suggests that in rainfed chickpea, a carefully timed weed removal could prevent grain yield losses.

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Corn Yield Loss Due to Volunteer Soybean

Weed Science ◽

10.1614/ws-d-16-00004.1 ◽

2016 ◽

Vol 64 (3) ◽

pp. 495-500 ◽

Cited By ~ 3

Author(s):

Jill Alms ◽

Sharon A. Clay ◽

David Vos ◽

Michael Moechnig

Keyword(s):

Loss Function ◽

Growth Stage ◽

Yield Loss ◽

Corn Yield ◽

Yield Losses ◽

Herbicide Resistant ◽

Growing Seasons ◽

Previous Season ◽

Control Volunteer ◽

Soybean Plants

The widespread adoption of glyphosate-resistant corn and soybean in cropping rotations often results in volunteer plants from the previous season becoming problem weeds that require alternative herbicides for control. Corn yield losses due to season-long volunteer soybean competition at several densities in two growing seasons were used to define a hyperbolic yield loss function. The maximum corn yield loss observed at high volunteer soybean densities was about 56%, whereas, the incremental yield loss (I) at low densities was 3.2%. Corn yield loss at low volunteer soybean densities was similar to losses reported for low densities of velvetleaf and redroot pigweed, with 10% yield loss estimated to occur at 3 to 4 volunteer soybean plants m−2. Several herbicides, including dicamba with or without diflufenzopyr applied at the V2 growth stage of volunteer soybean, provided > 90% control, demonstrating several economical options to control volunteer glyphosate-resistant soybean in glyphosate-resistant corn. Reevaluation of control recommendations may be needed with commercialization of other genetically modified herbicide-resistant soybean varieties.

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Quantification of Avoidable Yield Losses in Oilseed Brassica Caused by Insect Pests

Journal of Plant Protection Research ◽

10.2478/v10045-011-0007-y ◽

2011 ◽

Vol 51 (1) ◽

pp. 38-43 ◽

Cited By ~ 11

Author(s):

Jagdev Kular ◽

Sarwan Kumar

Keyword(s):

Seed Yield ◽

Yield Loss ◽

Insect Pests ◽

Block Design ◽

Maximum Yield ◽

The Other ◽

Yield Losses ◽

Eruca Sativa ◽

Mustard Aphid ◽

Randomized Block Design

Quantification of Avoidable Yield Losses in OilseedBrassicaCaused by Insect PestsA six year field study was conducted from 2001-2002 to 2006-2007 at Punjab Agricultural University, Ludhiana, India to study the losses in seed yield of differentBrassicaspecies (B. juncea, B. napus, B. carinata, B. rapaandEruca sativa) by the infestation of insect pests. The experiment was conducted in two different sets viz. protected/sprayed and unprotected, in a randomized block design, with three replications. Data on the infestation of insect pests, and seed yield were recorded at weekly intervals and at harvest, respectively. The loss in seed yield, due to mustard aphid and cabbage caterpillar, varied from 6.5 to 26.4 per cent.E. sativasuffered the least loss in seed yield and harboured the minimum population of mustard aphid (2.1 aphids/plant) and cabbage caterpillar (2.4 larvae/plant). On the other hand,B. carinatawas highly susceptible to the cabbage caterpillar (26.2 larvae/plant) and suffered the maximum yield loss (26.4%).

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Comparative Study of the Effect of Different Weed Management Strategies on Disease Severity and Marketable Yield of Paprika (Capsicum Annuum L.) in the Smallholder Farming Sector of Zimbabwe

Journal of Plant Protection Research ◽

10.2478/v10045-008-0011-z ◽

2008 ◽

Vol 48 (1) ◽

pp. 107-117 ◽

Cited By ~ 1

Author(s):

Maxwell Handiseni ◽

Julia Sibiya ◽

Vincent Ogunlela ◽

Irene Koomen

Keyword(s):

Comparative Study ◽

Capsicum Annuum ◽

Weed Management ◽

Leaf Spot ◽

Management Strategies ◽

Smallholder Farming ◽

Marketable Yield ◽

Weed Density ◽

Marketable Fruit ◽

Hand Weeding

Comparative Study of the Effect of Different Weed Management Strategies on Disease Severity and Marketable Yield of Paprika (Capsicum AnnuumL.) in the Smallholder Farming Sector of ZimbabweOn-farm trials were conducted in the Chinyika Resettlement Area of Zimbabwe under dryland conditions to investigate the effects of different weed management methods on disease incidence, severity and paprika (Capsicum annuum) pod yield. The weed control treatments included hand weeding at 2 and 6 weeks after transplanting (WAT); ridge re-moulding at 3,6 and 9 WAT; application 4l/ha Lasso (alachlor) immediately after transplanting, and Ronstar (oxidiazinon) at 2l/ha tank mixed with Lasso at 2l/ha one day before transplanting. The herbicide-water solution was applied at the rate of 200l/ha using a knapsack sprayer. Major diseases identified were bacterial leaf spot (Xanthomonas campestrispv.vesicatoria), cercospora leaf spot (Cercospora unamunoi), grey leaf spot (Stemphylium solani) and powdery mildew (Leveillula taurica) in both seasons. For the 2000/2001 season hand weeding at 2 and 6 WAT and ridge re-moulding at 3, 6 and 9 WAT had the greatest reduction effect on the area under disease progress curve (AUDPC) and the highest marketable fruit yield. In the 2001/2002 season, both herbicide treatments had the same effect as hand weeding and ridge re-moulding on AUDPC and marketable fruit yield. The least weed density was obtained by ridge re-moulding at 3, 6, and 9 WAT in the 2000/2001 season. Weed density was statistically the same across all treatments except the check treatment in 2001/2002 season. Hand weeding operations were significantly (p < 0.05) effective and consequently gave the highest added profits mainly because of their effect on major weeds such asDatura stramonium.

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Influence of Recovery Treatments on Dicamba-injured Soybean

Weed Technology ◽

10.1017/wet.2021.63 ◽

2021 ◽

pp. 1-20

Author(s):

Brian R. Dintelmann ◽

Shea T. Farrell ◽

Kevin W. Bradley

Keyword(s):

Yield Loss ◽

Yield Losses ◽

Soybean Yield ◽

Injury Reduction ◽

Stages Of Growth ◽

Average Precipitation ◽

Injury Event ◽

Recovery Treatment ◽

Micronutrient Fertilizer ◽

Similar Yield

Abstract Non-dicamba resistant soybean yield loss resulting from dicamba off-target injury has become an increasing concern for soybean growers in recent years. After off-target dicamba movement occurs onto sensitive soybean, little information is available on tactics that could be used to mitigate the cosmetic or yield losses that may occur. Therefore, a field experiment was conducted in 2017, 2018, and 2019 to determine if certain recovery treatments of fungicide, plant growth hormone, macro- and micronutrient fertilizer combinations, or weekly irrigation could reduce dicamba injury and/or result in similar yield to soybean that was not injured with dicamba. Simulated drift events of dicamba (5.6 g ae ha−1) were applied to non-dicamba resistant soybean once they reached the V3 or R2 stages of growth. Recovery treatments were applied approximately 14 d after the simulated drift event. Weekly irrigation was the only recovery treatment that provided appreciable levels of injury reduction or increases in soybean height or yield compared to the dicamba-injured plants. Weekly irrigation following the R2 dicamba injury event resulted in an 1% to 14% increase in soybean yield compared to the dicamba-injured control. All other recovery treatments resulted in soybean yields similar to the dicamba-injured control, and similar to or lower than the non-treated control. Results from this study indicate that if soybean have become injured with dicamba, weekly irrigation will help soybean recover some of the yield loss and reduce injury symptoms that resulted from off-target dicamba movement, especially in a year with below average precipitation. However, yield loss will likely not be restored to that of non-injured soybean.

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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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