Yield and Disease Responses of Improved Groundnut Genotypes Under Natural Disease Infection in Northern Uganda: Implication for Groundnut Disease Management

Groundnut production in Uganda is constrained by groundnut rosette disease (GRD), the main cause of yield loss experienced by farmers. We conducted the current study to assess the responses of improved groundnuts to diseases (rosette and late leaf spot) and yield under local conditions. Four released groundnut genotypes (Serenut 5R, Serenut 8R, Serenut 9T and Serenut 14R) were evaluated in four locations in northern Uganda for two seasons in 2019. We established the experiment following randomised complete block design with three replications. GRD severity (harvest) and late leaf spot (LLS) severity (harvest) on the four genotypes were not significantly (P > 0.05) different but positively correlated with the Area Under Disease Progress Curve (AUDPC). Genotype-by-location interaction for LLS AUDPC, GRD AUDPC and dry pod yield were significant (P < .001). Season-by-genotype interaction was not significant (P = 0.367). Days to 50% flowering were also not significant (P > 0.05). Highest and lowest yields were recorded for Serenut 9T in the Omoro district (1,291 kg/acre) and the Amuru district (609 kg/acre), respectively. Dry pod yield was significantly (P < 0.001) negatively correlated with GRD severity and GRD AUDPC. Yield performance of the four genotypes was not significantly (P < 0.05) different in the districts, except for Kitgum, where yields of Serenut 9T and Serenut 8R were significantly (P < 0.05) higher. These genotypes could be used to manage GRD by smallholder farmers in Northern Uganda. Special consideration should therefore be given to these four groundnut genotypes for GRD management in the Acholi sub-region.

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Rational Use of Fungicide Applications to Maximize Peanut Yield Under Foliar Disease Pressure in West Africa

Plant Disease ◽

10.1094/pdis.2000.84.11.1203 ◽

2000 ◽

Vol 84 (11) ◽

pp. 1203-1211 ◽

Cited By ~ 12

Author(s):

F. Waliyar ◽

Moustapha Adamou ◽

Aoua Traoré

Keyword(s):

West Africa ◽

Leaf Spot ◽

Field Trials ◽

Cercospora Arachidicola ◽

Causal Organism ◽

Late Leaf Spot ◽

Pod Yield ◽

Progress Curve ◽

The Cost ◽

Disease Pressure

Foliar diseases caused by Cercospora arachidicola, Cercosporium personatum, and Puccinia arachidis are major constraints to peanut production in the world. Fungicides are among the most efficient available control methods. Field trials were conducted in 1991 and 1992 in Benin and Niger, West Africa, to evaluate the cost effectiveness of fungicide application timings and frequencies on four peanut cultivars. A combination of four timings (40, 55, 70, and 85 days after sowing) was scheduled. Early (causal organism, C. arachidicola) and late (caused by C. personatum) leaf spot were prevalent in both years, but late leaf spot was the more economically important disease as shown by high values of area under the disease progress curve. Application of fungicide reduced late leaf spot incidence and increased pod yield. Pod yield responded to an interaction of number and timing of fungicide applications. With appropriate timing two or three fungicide applications were enough to significantly increase pod yield. Properly timed fungicide sprays can result in substantial monetary gains for peanut farmers in West Africa.

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Influence of Digging Date and Fungicide Program on Canopy Defoliation and Pod Yield of Peanut (Arachis hypogaea L.)

Peanut Science ◽

10.3146/ps07-011.1 ◽

2009 ◽

Vol 36 (1) ◽

pp. 77-84 ◽

Cited By ~ 4

Author(s):

Danésha S. Carley ◽

David L. Jordan ◽

Barbara B. Shew ◽

Turner B. Sutton ◽

L. Cecil Dharmasri ◽

...

Keyword(s):

North Carolina ◽

Arachis Hypogaea ◽

Leaf Spot ◽

Yield Loss ◽

Weekly Schedule ◽

Late Leaf Spot ◽

Pod Yield ◽

Arachis Hypogaea L ◽

Program Effects ◽

General Recommendation

Abstract Although response can be variable and is dependant upon many factors, digging peanut as little as 1 wk prior to or 1 wk following optimum maturity can result in substantial reductions in pod yield. While growers often assume that harvest should be initiated prior to optimum maturity in fields with high levels of canopy defoliation, there is no clear threshold where gains in pod weight and grade are offset by losses due to pod shedding. Moreover, yield loss relationships for foliar diseases have not been characterized for modern virginia market-type cultivars. Determining interactions between digging date and peanut canopy defoliation would assist growers and their advisors in making more informed decisions on when to initiate harvest to avoid yield loss. Research conducted from 2004–2005 in North Carolina established a range of defoliation levels in a total of seven fields. Fungicides were applied on a bi-weekly schedule from early July through mid-September, or were applied two times in July, or were not applied. Plots were dug early, 6 to 12 days before estimated optimum maturity, or at optimum maturity, as determined by the hull-scrape method. Although interactions between digging date and fungicide program were found in some cases, digging date and fungicide program effects often varied independently. A general recommendation of the percentage of canopy defoliation justifying early digging to prevent yield loss could not be determined from this research. However, data from these experiments reinforce the value of controlling early leaf spot, late leaf spot, and web blotch with timely fungicide applications and the importance of digging at optimum pod maturation for more recently released virginia market-type peanut.

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Calcium and potassium contents in nutrient solution on Phoma leaf spot intensity in coffee seedlings

Revista CERES ◽

10.1590/0034-737x201663040008 ◽

2016 ◽

Vol 63 (4) ◽

pp. 486-491 ◽

Cited By ~ 1

Author(s):

Aricléia de Moraes Catarino ◽

Edson Ampélio Pozza ◽

Adélia Aziz Alexandre Pozza ◽

Leone Stabile dias Santos ◽

Gabriel Brandão Vasco ◽

...

Keyword(s):

Nutrient Solution ◽

Leaf Spot ◽

Block Design ◽

Fungal Diseases ◽

Growth Chamber ◽

Spot Intensity ◽

Controlled Conditions ◽

Progress Curve ◽

Randomized Block Design ◽

Nutrient Solutions

ABSTRACT Coffee is one of the main export commodities of Brazilian agribusiness. Phoma leaf spot [Phoma tarda (Stewart) Boerema & Bollen] is one of the most important coffee fungal diseases in Brazil. Therefore, this study aimed to evaluate the intensity of Phoma leaf spot in coffee seedlings supplied with different rates of Ca+2 and K+. The study was conducted under controlled conditions in a growth chamber, at the Department of Phytopathology - UFLA, from February 2010 to December 2011. The assay was repeated twice under the same conditions. The nutrient solutions consisted of five concentrations of K+ (3, 4, 5, 6, 7 mmol L-1) and Ca+2 (2, 4, 6, 8 and 10 mmol L-1). The experiment was arranged in a randomized block design, with 25 treatments and three replicates, with two plants per plot. The areas under incidence progress curve (AUIPC) and severity (AUSPC) were calculated. At the lowest rate of Ca2+ (2 mmol L-1) and highest K+ (6 and 7 mmol L-1), approximately, the AUIPC was the smallest. For the AUSPC, the lowest rates of Ca+2 and K+ resulted in the lowest severities. Supply of Ca+2 and K+ in nutrient solution reduced AUIPC and AUSPC of Phoma leaf spot, and these nutrients can be recommended for the management of the disease.

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Genetics of Stay-Green Trait and Its Association with Leaf Spot Tolerance and Pod Yield in Groundnut

International Journal of Agronomy ◽

10.1155/2019/3064026 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11

Author(s):

Rukiya Danful ◽

Yussif Baba Kassim ◽

Doris Kanvenaa Puozaa ◽

Richard Oteng-Frimpong ◽

Masawudu Abdul Rasheed ◽

...

Keyword(s):

Leaf Spot ◽

Smallholder Farmers ◽

Recessive Gene ◽

Strong Relationship ◽

Sub Saharan Africa ◽

Yield Reduction ◽

Leaf Spot Disease ◽

Stay Green ◽

Disease Tolerance ◽

Pod Yield

Despite its importance in providing income and food for smallholder farmers, fodder for livestock, and improving soil fertility through biological nitrogen fixation, groundnut yields are lowest on farmers’ fields in Sub-Saharan Africa due to biotic and abiotic constraints. Foliar fungal diseases account for over 80% reduction in groundnut productivity in some parts of Ghana. Unfortunately, chemical control of these foliar diseases has not yielded the desired results. Meanwhile, advances in phenotyping for disease tolerance in other crops have established a strong relationship between stay-green trait and foliar disease tolerance. However, this relationship has not been explored in groundnut. This study was designed to determine the genetic control of the stay-green trait and its relationship with leaf spot disease severity in groundnut. Twenty-five advanced groundnut breeding lines with varying degrees of tolerance for leaf spot tolerance were evaluated under diseased and disease-free conditions, after which four were selected for genetic studies. Results showed significant (p<0.001) differences among the genotypes for early leaf spot (ELS), late leaf spot (LLS), leaf area under greenness (LAUG), SPAD chlorophyll meter readings (SCMR), and yield traits. Leaf spot diseases caused 4.95 t·ha−1 (64.54%) pod yield reduction in CHINESE, the widely cultivated groundnut variety in Ghana. There was a strong correlation between LAUG and ELS (r = 0.82, p<0.001) and LLS (r = 0.63, p<0.001), and genotypes that were stay-green had tolerance to both diseases. Stay-green trait in groundnut was detected to be under the control of a single recessive gene and hence may be used to select for ELS and LLS resistance.

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Improved Management Efficacy of Late Leaf Spot on Peanut Through Combined Application of Prothioconazole with Fluxapyroxad and Pyraclostrobin

Agronomy ◽

10.3390/agronomy10020298 ◽

2020 ◽

Vol 10 (2) ◽

pp. 298 ◽

Cited By ~ 3

Author(s):

Daniel J. Anco ◽

Justin B. Hiers ◽

James S. Thomas

Keyword(s):

South Carolina ◽

Leaf Spot ◽

Yield Loss ◽

Integrated Management ◽

Commercial Production ◽

Yield Potential ◽

Independent Action ◽

Late Leaf Spot ◽

Critical Part ◽

Combined Application

Late leaf spot, caused by Nothopassalora personata, is the most economically important fungal disease affecting peanut foliage in South Carolina and can result in combined management and yield loss costs of greater than 490 dollars/ha. Application of protectant fungicides is a critical part of effective integrated management under commercial production, and their strategic alternation and combination in management programs can provide enhanced control. Trials were conducted in Blackville, SC, from 2017 to 2019 to investigate whether combinations of prothioconazole with fluxapyroxad plus pyraclostrobin could provide more efficacious management of late leaf spot compared to either product alone. Two applications of 0.11 kg/ha prothioconazole with 0.05 kg/ha fluxapyroxad plus 0.1 kg/ha pyraclostrobin resulted in significantly (p < 0.05) less (24% to 42%) peanut canopy defoliation compared to the same number of applications of either product applied individually, with the combined application reflecting significant (p < 0.0202) synergism compared to component products as assessed through independent action methodology. An increased rate of fluxapyroxad plus pyraclostrobin application (0.1 and 0.2 kg/ha, respectively), with 0.16 kg/ha prothioconazole did not improve management relative to their combination at the examined lower rate (p = 0.89). Peanut yield was not adversely affected following combined applications. Cost-effectiveness of this combination depends on the actual disease intensity and yield potential of a given crop.

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Influence of Broadleaf Weeds on Chlorothalonil Deposition, Foliar Disease Incidence, and Peanut (Arachis hypogaea) Yield

Weed Technology ◽

10.1017/s0890037x00041336 ◽

1997 ◽

Vol 11 (1) ◽

pp. 51-58 ◽

Cited By ~ 14

Author(s):

Stanley S. Royal ◽

Barry J. Brecke ◽

Frederick M. Shokes ◽

Daniel L. Colvin

Keyword(s):

Arachis Hypogaea ◽

Leaf Spot ◽

Field Experiments ◽

Yield Loss ◽

Disease Incidence ◽

Weed Biomass ◽

Late Leaf Spot ◽

Foliar Disease ◽

Weed Density ◽

Weed Plants

Field experiments were conducted at Jay and Marianna, FL in 1988 and 1989 to determine the effects of sicklepod, Florida beggarweed, and common cocklebur density on chlorothalonil deposition to peanut foliage, peanut foliar disease incidence, and peanut yield. At a density of four weed plants per 8 m of row, Florida beggarweed and sicklepod reduced chlorothalonil deposition on peanut foliage by 20%, while common cocklebur reduced fungicide deposition by 34%. At the same density, incidence of the foliar diseases early leaf spot and late leaf spot increased 10% with Florida beggarweed, 14% with sicklepod, and 20% with common cocklebur compared with weed-free peanut. The predicted peanut yield loss from a weed density of four plants per 8 m was 16 to 19% for Florida beggarweed, 23 to 25% for sicklepod, and 31 to 39% for common cocklebur. Weed biomass increased with increasing weed density.

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Screening Groundnut (Arachis hypogeae) Genotypes for Resistance to Early and Late Leaf Spot Diseases

Journal of Experimental Agriculture International ◽

10.9734/jeai/2019/v37i430274 ◽

2019 ◽

pp. 1-9

Author(s):

M. S. Alidu ◽

S. Abukari ◽

M. Abudulai

Keyword(s):

Leaf Spot ◽

Agricultural Research ◽

Block Design ◽

Northern Region ◽

Limiting Factors ◽

Leaf Spot Disease ◽

Cercospora Arachidicola ◽

Late Leaf Spot ◽

Arachis Hypogaea L ◽

Significant Difference

Background for the Study: Groundnut (Arachis hypogaea L.) is an important crop both in subsistence and commercial agriculture in Ghana. Early leaf spot (Cercospora arachidicola) and late leaf spot (Cercosporidium personata) are major limiting factors to groundnut productivity in Ghana. Aim: The objective of the study was to screen groundnut genotypes for resistance to Early and Late leaf spot diseases. Study Design: The treatments were arranged in a randomized complete block design and replicated three (3) times. Place and Duration of Study: The research was conducted from May to December 2013 at the Savanna Agricultural Research Institute experimental site at Nyankpala in the Northern Region. The site lies between latitude 9°25´141 North and longitude 0°58’142 West and an altitude of 183 m. Methodology: The land was done using a tractor and field divided into plots of 2 m x 5 m with 1 m interval between plots. Sowing was done on 3rd June 2013. One seed was planted per hole at a depth of approximately 4 cm. Early and late leaf spot ratings were recorded at 30, 60 and 90 days after planting, using a ten-point scale. At pod maturity, plants from the middle two rows of each plot were hand-harvested and weights of the above ground foliage and underground pods were oven-dried to obtain dry haulm weight and pod yield respectively. Data collected were subjected to analysis of variance using Genstat statistical package (12th edition). Means were separated using the least significant difference at 5%. Results: The were significant differences (P < .001) among the groundnut genotypes in terms of severity for both early and late leaf spot diseases. F-Mix, NC 7, PC 79-79, F-Mix × SINK 24 and NKATIE-SARI had lowest score for both early and late leaf spot diseases. Among the 21 groundnut genotypes, F-Mix recorded the highest pods yield of 1100kg/ha and haulm weight of 5867 kg/ha followed by NC 7 with total pods yield of 900 kg/ha and haulm weight of 5373 kg/ha. PC 79-79 had a total pods yield of 666.7 kg/ha and haulm weight of 4867kg/ha. The pods yield of F-Mix × SINK 24 was 533.3 kg/ha and haulm weight of 4600 kg/ha. NKATIE-SARI recorded pods yield of 500 kg/ha and haulm weight of 4633 kg/ha. Conclusions: From the study, the genotypes F-Mix, NC 7, PC 79-79, F-Mix × SINK 24 and NKATIE-SARI were found to be resistance to both early and late leaf spot disease whereas Chinese, Doumbala, GM 120, GM 324 and ICGV 86015 were susceptible to both diseases.

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Effective Plant Ages for Screening for Field Resistance to Alternaria Leaf Spot (Caused by Alternaria spp.) under Natural Infection in Jerusalem artichoke (Helianthus tuberosus L.)

Agronomy ◽

10.3390/agronomy9110754 ◽

2019 ◽

Vol 9 (11) ◽

pp. 754 ◽

Cited By ~ 1

Author(s):

Wanalai Viriyasuthee ◽

Suwita Saepaisan ◽

Weerasak Saksirirat ◽

Mark L. Gleason ◽

Ruey Shyang Chen ◽

...

Keyword(s):

Leaf Spot ◽

Disease Incidence ◽

Natural Infection ◽

Block Design ◽

Jerusalem Artichoke ◽

Plant Age ◽

Growth Stages ◽

Alternaria Leaf Spot ◽

Progress Curve ◽

The Impact

Host plant resistance has proven to be effective for controlling Alternaria leaf spot on Jerusalem artichoke (JA), but efficient screening techniques have not been developed yet. The objective of this study is to estimate the relationship between disease resistance parameters of JA as a function of plant age. Six JA varieties and three plant ages at the time of inoculation (20, 40 and 60 days after transplanting) (DAT) are evaluated in a factorial experiment in randomized complete block design (RCBD) with four replications. Disease incidence (DI) and severity (DS) are estimated, from which area under the disease progress curve (AUDPC) was calculated. Disease parameters are positively and significantly correlated for plant ages of 40 and 60 DAT. Based on our results, screening of JA at 40 DAT for resistance to Alternaria leaf spot is recommended. Knowledge of the impact of plant age on resistance to key diseases can help breeders to accelerate breeding programs so superior genotypes can be identified before reproductive growth stages.

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Comparative Transcriptome Analysis Identified Candidate Genes for Late Leaf Spot Resistance and Cause of Defoliation in Groundnut

International Journal of Molecular Sciences ◽

10.3390/ijms22094491 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4491

Author(s):

Sunil S. Gangurde ◽

Spurthi N. Nayak ◽

Pushpesh Joshi ◽

Shilp Purohit ◽

Hari K. Sudini ◽

...

Keyword(s):

Disease Resistance ◽

Resistance Genes ◽

Transcriptome Analysis ◽

Leaf Spot ◽

Yield Loss ◽

Disease Resistance Genes ◽

Resistance Locus ◽

Comparative Transcriptome ◽

Late Leaf Spot ◽

Comparative Transcriptome Analysis

Late leaf spot (LLS) caused by fungus Nothopassalora personata in groundnut is responsible for up to 50% yield loss. To dissect the complex nature of LLS resistance, comparative transcriptome analysis was performed using resistant (GPBD 4), susceptible (TAG 24) and a resistant introgression line (ICGV 13208) and identified a total of 12,164 and 9954 DEGs (differentially expressed genes) respectively in A- and B-subgenomes of tetraploid groundnut. There were 135 and 136 unique pathways triggered in A- and B-subgenomes, respectively, upon N. personata infection. Highly upregulated putative disease resistance genes, an RPP-13 like (Aradu.P20JR) and a NBS-LRR (Aradu.Z87JB) were identified on chromosome A02 and A03, respectively, for LLS resistance. Mildew resistance Locus (MLOs)-like proteins, heavy metal transport proteins, and ubiquitin protein ligase showed trend of upregulation in susceptible genotypes, while tetratricopeptide repeats (TPR), pentatricopeptide repeat (PPR), chitinases, glutathione S-transferases, purple acid phosphatases showed upregulation in resistant genotypes. However, the highly expressed ethylene responsive factor (ERF) and ethylene responsive nuclear protein (ERF2), and early responsive dehydration gene (ERD) might be related to the possible causes of defoliation in susceptible genotypes. The identified disease resistance genes can be deployed in genomics-assisted breeding for development of LLS resistant cultivars to reduce the yield loss in groundnut.

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Diallel Analysis of Early Leaf Spot (Cercospora arachidicola Hori) Disease Resistance in Groundnut

Agronomy ◽

10.3390/agronomy9010015 ◽

2019 ◽

Vol 9 (1) ◽

pp. 15 ◽

Cited By ~ 2

Author(s):

Adama Zongo ◽

Abdourasmane K. Konate ◽

Kadidia Koïta ◽

Mahamadou Sawadogo ◽

Philippe Sankara ◽

...

Keyword(s):

Disease Resistance ◽

Leaf Spot ◽

Gene Action ◽

Block Design ◽

Regression Line ◽

Cercospora Arachidicola ◽

Additive Gene Action ◽

Progress Curve ◽

Additive Gene ◽

Resistance Traits

Early leaf spot (ELS) is one of the major biotic constraints of groundnut production in West and Central Africa. A study using 6 × 6 F2 full diallel populations from six parents (NAMA, B188, PC79-79, QH243C, TS32-1, and CN94C) was conducted to assess the mode of inheritance of ELS resistance traits. The F2 and parents were grown in a randomized complete block design with three replications. Data was collected on ELS disease severity, and an area under disease progress curve (AUDPC) was estimated. The results revealed that additive and non-additive gene actions were involved in the inheritance of the ELS resistance traits, but additive gene action was predominant. Significant reciprocal cross effect was observed, suggesting cytoplasmic effect on ELS resistance. Graphical analysis also revealed the predominance of additive gene action for ELS resistance. The results suggest that early generation selection should be effective for ELS resistance. Looking at the distribution of array points along with the regression line, parental lines NAMA, PC79-79, and B188 would be suitable as good donors in an ELS disease resistance breeding program.

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