Inheritance of resistance to anthracnose stalk rot (Colletotrichum graminicola) in tropical maize inbred lines

Generation means was used to study the mode of inheritance of resistance to anthracnose stalk rot in tropical maize. Each population was comprised of six generations in two trials under a randomized block design. Inoculations were performed using a suspension of 10(5) conidia mL-1 applied into the stalk. Internal lesion length was directly measured by opening the stalk thirty days after inoculation. Results indicated contrasting modes of inheritance. In one population, dominant gene effects predominated. Besides, additive x dominant and additive x additive interactions were also found. Intermediate values of heritability indicated a complex resistance inheritance probably conditioned by several genes of small effects. An additive-dominant genetic model sufficed to explain the variation in the second population, where additive gene effects predominated. Few genes of major effects control disease resistance in this cross. Heterosis widely differed between populations, which can be attributed to the genetic background of the parental resistant lines.

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Genetic control of resistance to gray leaf spot of maize in tropical germplasm

Cropp Breeding and Applied Biotechnology ◽

10.1590/s1984-70332012000200008 ◽

2012 ◽

Vol 12 (2) ◽

pp. 145-150 ◽

Cited By ~ 2

Author(s):

André Humberto de Brito ◽

Livia Maria Chamma Davide ◽

Renzo Garcia Von Pinho ◽

Rafael Pelloso de Carvalho ◽

Matheus Costa dos Reis

Keyword(s):

Genetic Control ◽

Leaf Spot ◽

Genetic Model ◽

Block Design ◽

Gray Leaf Spot ◽

Cercospora Leaf Spot ◽

Gene Effects ◽

Randomized Block Design ◽

Tropical Germplasm ◽

Plant Level

The main goal of this study was to assess the nature and magnitude of gene effects for resistance to Cercospora leaf spot. A randomized block design with three replications was used. The data were obtained at the plant level by assessing the disease severity. The data were analyzed per experiment, using the average data per plot. A dominant-additive genetic model without epistasis was considered, with estimation of the components of means and variance. The genetic control of resistance to gray leaf spot is polygenic with predominance of the additive effects. Dominance was observed in a few small-effect loci and high heritability values.

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Generation Mean Analysis in Cowpea [Vigna unguiculata (L.) Walp.] under Flower Thrips infestation

Journal of Agricultural Science ◽

10.5539/jas.v10n4p86 ◽

2018 ◽

Vol 10 (4) ◽

pp. 86 ◽

Cited By ~ 1

Author(s):

Gonné Sobda ◽

Fonji Maureen Atemkeng ◽

Ousmane Boukar ◽

Chistian Fatokun ◽

Pangirayi Bernard Tongoona ◽

...

Keyword(s):

Block Design ◽

Generation Mean Analysis ◽

Flower Number ◽

Narrow Sense Heritability ◽

Gene Effects ◽

Flower Thrips ◽

Randomized Block Design ◽

Cowpea Resistance ◽

Predominant Type ◽

Screen House

Two sets of six generations (P1, P2, F1, F2, BC1P1, BC1P2) of cowpea were developed from crosses of contrasting inbred lines VYA (susceptible) × SANZI (resistant) and LORI (susceptible) × SANZI (resistant). The aim of this study was to determine the inheritance and elucidate the genetic control of cowpea resistance to thrips. The first set (VYA × SANZI) was evaluated under natural thrips infestation in the field in a completely randomized block design with three replications. The second set (LORI × SANZI) was screened using artificial thrips infestation in the screen house. In each trial, data were recorded on 150 individual plants. These included the score of thrips damages using the scale of one to nine, number of thrips per flower, number of pods per plant, pod weight per plant and grain weight per plant. The generation mean analysis revealed that both additive and non-additive types of gene effects were significant. Dominance × dominance was the most predominant type of gene effects for thrips resistance, suggesting that breeders should delay selection to late generations to allow advancement of as many high-potential recombinants as possible during hybridization. The number of genes that control the expression of number of thrips per flower was three and ranged from three to four, for score of thrips damages. High broad sense and moderate narrow sense heritability were observed ranging from 0.53 to 0.65 and 0.14 to 0.36, respectively for all of the traits measured.

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Evaluation of the virulence of Sclerotium rolfsii isolates on Arachis hypogaea and screening for resistant genotypes in greenhouse conditions

Hellenic Plant Protection Journal ◽

10.1515/hppj-2015-0001 ◽

2015 ◽

Vol 8 (1) ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

A.A. Eslami ◽

S.A. Khodaparast ◽

S. Mousanejad ◽

F. Padasht Dehkaei

Keyword(s):

Plant Height ◽

Block Design ◽

Sclerotium Rolfsii ◽

Soil Surface ◽

Lesion Length ◽

Randomized Block Design ◽

Wide Range ◽

Mycelial Compatibility ◽

Pathogenicity Tests ◽

Plant Maturity

Summary Sclerotium rolfsii is a soil borne pathogen responsible for root and stem rot on a wide range of crops. This study was conducted to identify the virulence of different S. rolfsii isolates on a susceptible local peanut germplasm and determine the resistance of 20 peanut genotypes to the most virulent isolate and also the relationship between virulence and mycelial compatibility groups (MCGs). Seventy eight isolates of this fungus from 10 host plants and six known MCGs were used in the experiment. The experiment was done in greenhouse conditions (25±5°C) using a complete randomized block design with three replications. Pots containing sterile soil (pH=6.7) were inoculated with barley seeds colonized by each isolate separately before being seeded with the peanut germplasm. Disease severity was assessed by scoring the wilting, yellowing or death of plants, mycelia or sclerotia production on the soil surface or on plant stem, stem area affected (%) and stem lesion length, at the stage of plant maturity. Also, shoot wet weight and plant height were recorded at this stage. According to the results of the pathogenicity tests, all of the isolates were virulent on the susceptible peanut germplasm and the virulence diff ered signifi cantly between the isolates (P≤0.01). There was no relationship between the virulence of the five groups of isolates identified in the present study and the MCGs. The peanut genotype 140, which was better than the others based on seed size, plant height and the canopy size, was also the most resistant one

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Evaluation of genetic potential of shoot fly resistant sources in sorghum (Sorghum bicolor (L.) Moench)

The Journal of Agricultural Science ◽

10.1017/s0021859608008277 ◽

2008 ◽

Vol 147 (1) ◽

pp. 71-80 ◽

Cited By ~ 15

Author(s):

C. ARUNA ◽

P. G. PADMAJA

Keyword(s):

Block Design ◽

Trichome Density ◽

Male Sterile ◽

Seedling Vigour ◽

Gene Effects ◽

Shoot Fly ◽

Randomized Block Design ◽

Sorghum Shoot Fly ◽

Additive Gene ◽

And Cluster Analysis

SUMMARYTwelve sorghum lines resistant to sorghum shoot fly were evaluated for their combining ability for shoot fly resistance and traits associated with resistance, using three male sterile lines in two environments. Using a completely randomized block design with three replications, 36 hybrids and 15 parental genotypes were raised. Considerable genetic variation was observed for all the traits studied. Non-additive gene effects played an important role in governing glossiness, seedling vigour and proportion of plants with deadhearts. For trichome density, both additive and non-additive gene actions were important. Among the lines evaluated, those identified to be good combiners were SFCR 1047 for seedling vigour, deadheart proportion and trichome density, RSE 03 for glossiness, deadheart proportion at 21 DAE and trichome density, and SPSFR 94032 for seedling vigour and shoot fly eggs per plant. Genetic diversity and cluster analysis grouped the 15 parents (12 resistant and 3 susceptible parents) into five clusters. Utilization of the resistant lines belonging to different clusters in improving shoot fly resistance in sorghum is discussed.

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KETAHANAN DELAPAN KULTIVAR TEMBAKAU LOKAL BONDOWOSO TERHADAP TIGA PATOGEN PENTING (Ralstonia solanacearum, Pectobacterium carotovorum, DAN Phytophthora nicotianae)

Jurnal Penelitian Tanaman Industri ◽

10.21082/jlittri.v18n3.2012.89-94 ◽

2020 ◽

Vol 18 (3) ◽

pp. 89

Author(s):

TITIEK YULIANTI ◽

NURUL HIDAYAH ◽

SRI YULAIKAH

Keyword(s):

Ralstonia Solanacearum ◽

Block Design ◽

Production Quality ◽

Phytophthora Nicotianae ◽

Pectobacterium Carotovorum ◽

Resistance Level ◽

Stalk Rot ◽

Randomized Block Design ◽

Tobacco Production ◽

Screen House

ABSTRAK Tembakau bondowoso merupakan tembakau lokal rajangan yang berkembang di Kabupaten Bondowoso, Jawa Timur. Saat ini ada delapan kultivar dengan karakter produksi, mutu, dan ketahanannya terhadap penyakit yang berbeda. Layu bakteri (Ralstonia solanacearum), busuk batang berlubang (Pectobacterium carotovorum), dan lanas (Phytophthora nicotianae) merupakan penyakit yang sering menyebabkan turunnya produksi tembakau bondowoso. Evaluasi ketahanan delapan kultivar tembakau bondowoso (Samporis, Serumpung, Marakot, Samporis Lokal, Samporis AH, Samporis CH, Samporis B. Disbun, dan Deli) terhadap ketiga patogen tersebut dilaksanakan di laboratorium dan rumah kasa Balai Penelitian Tanaman Pemanis dan Serat (Balittas) mulai bulan April sampai dengan Oktober 2011. Penelitian terhadap ketiga patogen tersebut dilakukan secara terpisah. Masing-masing kultivar ditanam sebanyak 10 tanaman, 1 tanaman/polibag. Setiap perlakuan (kultivar) diulang 3 kali dan disusun dalam rancangan acak kelompok (RAK). Inokulasi R. solanacearum dan P. carotovorum dilakukan secara terpisah 24 jam sebelum transplanting. Inokulasi P. nicotianae dilakukan dengan dua cara, yaitu melalui akar dan pangkal batang. Inokulasi akar sama dengan cara inokulasi bakteri. Inokulasi pangkal batang dilakukan pada tanaman berumur 2 minggu setelah transplanting. Pengamatan intensitas penyakit dilakukan setiap minggu selama 11 minggu. Hasil penelitian menunjukkan bahwa kultivar Samporis CH, Samporis, dan Deli tahan terhadap P. carotovorum, R. solanacearum, dan P. nicotianae. Kultivar Samporis CH., Samporis, dan Deli ketahanannya lebih tinggi terhadap ketiga patogen, dengan intensitas penyakit berkisar antara 3,3%-6,7%. Kultivar Marakot sangat rentan terhadap ketiga patogen tersebut dengan tingkat keparahan ≥ 50%. Demikian pula kultivar Samporis AH yang rentan terhadap R. solanacearum, P. nicotianae dan P. carotovorum dengan intensitas penyakit 23,3-53,3%. Oleh karena itu, kultivar Samporis CH, Samporis, dan Deli cocok dikembangkan pada lahan endemik penyakit tular tanah di Kabupaten Bondowoso. Kata kunci: tembakau bondowoso, Pectobacterium carotovorum Phytophthora nicotianae, Ralstonia solanacearum, ketahananABSTRACT Bondowoso tobacco is a local type of sliced tobacco which is restrictedly cultivated in Bondowoso Regency, East Java. There are eight cultivars known, ie. Samporis, Serumpung, Marakot, Samporis Lokal, Samporis AH, Samporis CH, Samporis B. Disbun, and Deli with their own distinctive characters on their production, quality, and resistance to diseases. Bacterial wilt (Ralstonia solanacearum), hollow stalk rot (Pectobacterium carotovorum), and blackshank (Phytophthora nicotianae are the main cause of bondowoso tobacco production loss. Evaluation on the resistance level of the cultivars to the three pathogens above has been conducted at a laboratory and screen house scale in Indonesian Sweetener and Fibre Crops Research Institute from April to October 2011. The evaluation of each pathogen was conducted separately. Each evaluation of the pathogen per cultivar used 10 plants planted individually in a polybag. The experiment was arranged in a randomized block design with 3 replicates. R. solanacearum and P. carotovorum were separately inoculated on the test plants 24 h before transplanting. The inoculation of P. nicotianae was done twice via the root and stem. Disease intensity was observed weekly for 11 weeks. The results showed that Samporis CH, Samporis, and Deli cultivars were resistant to P. carotovorum, R. solanacearum and P. nicotianae, whereas Samporis and Deli cultivars were more resistant to the pathogens (disease intensity ranged 3.3-6.7%). Marakot cultivar was very susceptible to all of the three pathogens (disease intensity ≥ 50%). Similarly, Samporis AH cultivar was also susceptible to the pathogens with disease intensity ranged 23.3-53.3%. The study indicated that Samporis CH, Samporis, and Deli cultivars are suitable to be cultivated in the endemic soil born pathogen areas of Bondowoso Regency. Key words: bondowoso tobacco, Pectobacterium carotovorum, Phytophthora nicotianae, Ralstonia solanacearum, resistance

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Center pivot irrigation management in maize hybrids and the incidence of stalk rot

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v24n12p840-846 ◽

2020 ◽

Vol 24 (12) ◽

pp. 840-846

Author(s):

Irineu E. Kühn ◽

Mayara F. Cotrim ◽

Ricardo Gava ◽

Rita de C. F. Alvarez ◽

Job T. de Oliveira ◽

...

Keyword(s):

Block Design ◽

Irrigation Management ◽

Management Strategies ◽

Irrigation Frequency ◽

Maize Hybrids ◽

Stalk Rot ◽

Randomized Block Design ◽

Center Pivot ◽

Irrigation Depth ◽

The One

ABSTRACT This study aimed to verify the incidence of Fusarium spp. in commercial maize hybrids and irrigation management strategies utilizing center pivot systems. The experiment was carried out during the second season in a randomized block design with a split-plot arrangement with five maize hybrids (2B810, MG580, AS1633, DKB290, and AG8544). The plots were irrigated with five frequencies (1, 2, 3, 4, and 5 days) in one experiment, and five water depths (at 25, 50, 75, 100, and 125% of crop evapotranspiration) in another experiment. Plant height, ear insertion height, moisture at harvest time, yield, and incidence of stalk rot were evaluated. Neither irrigation frequency nor irrigation depth influenced the incidence of disease. The one-day irrigation frequency provided the highest yield for maize hybrids. Hybrid 2B810 showed the highest yield and the lowest incidence of the disease.

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Expression of Heterosis for Productive Traits in Bottle Gourd Hybrids

Journal of Botanical Research ◽

10.30564/jrb.v2i2.1828 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

AKM Quamruzzaman ◽

M.M.R. SALIM ◽

L. AKHTER ◽

M.M. RAHMAN ◽

M.A. Z. CHOWDHURY

Keyword(s):

Agricultural Research ◽

Block Design ◽

Diallel Cross ◽

Bottle Gourd ◽

Research Centre ◽

Gene Effects ◽

Randomized Block Design ◽

Additive Gene ◽

The Cross ◽

Productive Traits

A study was conducted in bottle gourd to estimate the magnitude of heterosis for yield and its thirteen yield related components. Twenty one bottle gourd hybrids generated from 7 × 7 diallel cross (excluding reciprocals) along with their seven parents evaluated in a Randomized Block Design with three replication at at the Olericulture Division of Horticulture Research Centre, Bangladesh Agricultural Research Institute (BARI), Gazipur, Bangladesh during 2018-19. Most of the crosses showed significant heterobeltiosis for earliness. The highest heterobeltiotic effect was observed in the cross P2XP7 and P4XP7. The best heterotic cross for fruit length was P4XP5. Maximum heterotic effect in respect of fruit number per plant was found in the cross P1XP6 and P4XP6. In terms of yield per plant the highest heterobeltiosis was shown by the crosses P3XP4, P3XP5, P4XP5 and P4XP7. In the overall analysis, both additive and non-additive gene actions were found important with predominance of the additive gene effects in the inheritance of bottle gourd.

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Inheritance of resistance to downy mildew (Peronosclerospora maydis) in crossing of Madura Maize Plant (Zea mays L.)

10.21107/amzeri.2019.1 ◽

2019 ◽

Author(s):

Achmad Amzeri ◽

◽

Kaswan Badami ◽

Gita Pawana ◽

◽

...

Keyword(s):

Downy Mildew ◽

Block Design ◽

Dominant Gene ◽

Genetic Resistance ◽

Technology Study ◽

Study Program ◽

Randomized Block Design ◽

Degree Of Dominance ◽

Maize Genetic ◽

Mdr 1

Hybridization of Back cross is one method to get varieties that are resistant to downy mildew. The purpose of this study was to obtain information on inheritance characteristics of downy mildew resistance. This research was conducted at the experiment center of Agro-Technology Study Program of Agriculture Faculty, University of Trunojoyo Madura. Research of Assessment of resistance to Downy Mildew used a randomized block design with 18 treatments (P1, P2, F1, F2, BC1P1 and BC1P2 in three sets of crosses, namely LGL x Mdr-3, T12 x Mdr-1 and E02 x Mdr-2) and three replications so there were 54 experimental units. Identification of polymorphic RAPD markers for endurance to downy mildew through Bulk Segregant Analysis (BSA) was done by amplifying the DNA in the resistant pool and susceptible pool. The random primers used were 120 primers from 6 operon groups, namely OPA, OPB, OPC, OPD, OPF and OPG. The results showed that the inheritance pattern of maize genetic resistance to downy mildew followed a segregation pattern of 3:1 with a degree of dominance between -1 and 0, and was controlled by incomplete partially negative dominant gene. OPC-07 was a marker that was linkage close to the resistance to downy mildew with a genetic distance of 1.9 cM.

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TINDAK GEN KETAHANAN TERHADAP PENYAKIT KARAT (Pucinnia arachidis, Speg.) PADA KACANG TANAH

Jurnal Ilmu-Ilmu Pertanian Indonesia ◽

10.31186/jipi.9.2.172-177 ◽

2017 ◽

Vol 9 (2) ◽

pp. 172-177

Author(s):

Juli Santoso

Keyword(s):

Disease Resistance ◽

Breeding System ◽

Gene Action ◽

Block Design ◽

Dominant Gene ◽

Action Control ◽

Rust Disease ◽

Gene Effect ◽

Randomized Block Design ◽

Allelic Interaction

The rust disease resistance of groundnut has inherited pattern 9 : 7, indicating that was controlled by double resessive genes. From this fact needs an explanation of gene action, so it can be used as information in the breeding system and selection. The purpose of this research is to know the gene action control, if resistant the rust disease in groundnut. The design used in this experiment was randomized block design with three replications. There were 29 genotypes as treatments (5 genotypes parents, 6 genotypes F1, 6 genotypes F2, 6 genotypes BC1.1 and 6 genotypes BC1.2). The result of the experiment showed that there was a gene non-allelic interaction, mean effect (m) and a dominant gene effect (h) in progeny of Muneng x ICGV 87358 (Six Parameters Mode). However, the gene non-ellelic interaction did not occur in other progenies. Meanwhile progenies of Gajah x ICGV 92088, Gajah x ICGV 87358, Gajah x ICGV 91227 had a mean effect (m) and a aditive gene effect (d), and Muneng x ICGV 92088, Muneng x ICGV 91227 had only a mean effect (m).

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Comparisons of unweighted with weighted least squares methods of fitting a genetic model to a diallel cross

Genome ◽

10.1139/g89-510 ◽

1989 ◽

Vol 32 (5) ◽

pp. 771-782 ◽

Cited By ~ 1

Author(s):

Hugh Tyson

Keyword(s):

Least Squares ◽

Genetic Model ◽

Block Design ◽

Weighted Least Squares ◽

Diallel Cross ◽

Adequate Model ◽

Mean Values ◽

Randomized Block Design ◽

Reciprocal Differences ◽

Predicted Values

Data on mean seed weight from the F1 of a complete 6 by 6 diallel cross with flax (Linum usitatissimum), grown in a randomized block design, were used to evaluate the benefits of weighted compared with unweighted least squares fitting of a genetical model for this type of cross. The model examines combining abilities and reciprocal differences. Matrix methods were employed in this study for weighted and unweighted least squares solutions. These methods accommodate rapid modification of appropriate models through changes in the corresponding design matrices, the use of various types of weight, the handling of missing data, the construction of orthogonal sets of parameters, the calculation of sums of squares accounted for by one or more of the parameters in the model, and the analysis of variance of the data. Weights used here were reciprocals of variances of diallel cell means, i.e., a variance reflecting variation among replicate mean values for a given cell. Weighted fitting with sequential elimination of redundant parameters in the original model extracted the minimum adequate model. Predicted values, generated from significant parameters in weighted or unweighted fittings of the model to overall F1 and parental means, were compared. Deliberate, increasing distortion of data in one replicate of the randomized block design showed that weighted fitting of the model distinguished consistent diallel data from distorted, giving predicted values reflecting the more reliable observations.Key words: diallels, weighted versus unweighted fitting.

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