Sources of resistance in chickpea (Cicer arietinum L.) to ascochyta blight (Ascochyta rabiei)

  1. Koleva1, Y. Stanoeva2, I. Kiryakov2, A. Ivanova1


1Department of Crop Science and Plant protection, College Dobrich, University Bishop Konstantin Preslavski-Shumen, 9300 Dobrich, Bulgaria

2Dobroudzha Agricultural Institute, 9520 General Toshevo, Bulgaria


DOI: 10.15547/ast.2018.03.037

(Manuscript received 4 June 2018; accepted for publication 3 August 2018)


Abstract. Ascochyta blight is the major biotic stress that causes significant yield losses in chickpea (Cicer arietinum L.) all over the world. The disease is caused by the fungus Ascochyta rabiei (Pass.) Lab (telemorph Dydimella rabiei = Mycosphaerella rabiei (Kovachevski) v. Arx. The use of resistant cultivars is widely acknowledged as the most economic and environmentally friendly method for disease control. The aim of this study is to screen chickpea cultivars and lines for resistance to ascochyta blight with a view for using them in a breeding program. The investigations were carried out during 2012-2017 in Dobroudzha Agricultural Institute (DAI) – General Toshevo. Twenty chickpea accessions were inoculated under field and greenhouse conditions with 30 Ascochyta rabiei isolates. Disease reaction was estimated after 14 days by using 9-degree scale. Disease incidence (DI) was calculated according to the Mc Kinney index. Cluster analysis was used to group the accessions and isolates according to the DI. Nine accessions showed middle resistance under field conditions during the three years of investigations. No immune or resistant accession to all 30 isolates was found under greenhouse conditions. The cluster analysis grouped the accessions into two major classes. One of the classes consists of two accessions (XOOC01CA0490B0223D and XOOC01CA0490B2140D) which showed middle resistance to 12 and 13 of the isolates, respectively. The cluster analysis grouped the isolates into classes, subclasses and sub sub classes according to their virulence to the 20 chickpea accessions. The highest virulence showed five isolates (AR 883, AR 061, AR R1, AR 1013, AR 1015) with DI from 5.40 to 9.00 in all accessions. Differences in field and greenhouse results were expected and they were due to the strong dependence of disease development to climatic conditions. The results in this investigation showed that two chickpea accessions can be used in a breeding program for ascochyta blight resistance.

Evaluation of lentil cultivars and lines for resistance toFusarium oxysporum f.sp. lentis

  1. Koleva1*, Y. Stanoeva2, I. Kiryakov2, A. Ivanova1, P. Chamurlyiski1


1Shumen University “Bishop Konstantin Preslavski”, College Dobrich, Department of Crop Science and Plant protection, 9300 Dobrich, Bulgaria

2 Dobroudzha Agricultural Institute, 9500 General Toshevo, Bulgaria

(Manuscript received 10 July 2017; accepted for publication 18 January 2018)


Abstract. Lentil (Lens culinaris Medik.) is one of the most important food legume crops in the farming and food systems of many countries, including Bulgaria. In recent years lentil fields increased in our country. Fusarium wilt caused by Fusarium oxysporum f.sp. lentis (F.o. f.sp. lentis) is a key yield-limiting factor worldwide. The major approach to control the disease is through resistance breeding. The aim of this investigation was to screen lentil cultivars and lines for resistance to F.o. f.sp. lentis. The investigations were carried out during 2013-2015. Thirty two lentil accessions were sown in 1m rows, in three replications. Barley grains (100g/m) inoculated with mix of four isolates of F.o. f.sp. lentis were used as inoculum. Disease reaction was estimated during flowering and pod filling stage according to 9 degree scale. The disease incidence (DI) of every accession was calculated according to McKinney index. Cluster analysis was used to group the accessions according to DI. ‘Genotype’ x ‘Year’ interaction was estimated by Two-way ANOVA. The results showed that middle disease incidence (MDI) was the highest in 2014 and the lowest in 2015. Our investigation confirms the results of many authors that disease incidence of F.o. f.sp. lentis on lentil was determined by the interaction of the factors ‘Genotype’x‘Year’. The cluster analysis grouped the accessions into two major classes. No resistant accessions were found. Six accessions showed MDI from 48.59 to 58.11 and they can be used in a genetic-improvement breeding program for fusarium wilt resistance.

Screening of cucurbitaceous rootstocks against root-knot nematodes (Meloidogyne spp.) and soilborne pathogens (Fusarium spp. and Pythium spp.)

V. Yankova*, D. Markova, N. Velkov, S. Masheva

Maritsa Vegetable Crops Research Institute, 32 Brezovsko shosse, 4003 Plovdiv, Bulgaria (Manuscript received 22 August 2016; accepted for publication 30 January 2017)

Abstract. One of the main problems in cucumber greenhouse production is control of soil-borne pathogens and root-knot nematodes. Grafting cucumber plants represent an alternative method to control that is safety and does not pollute the environment. Immune forms to these pests are not established, but in some studies are found sources belong to Cucurbitaceae family that possesses resistant or tolerant response. The aim of this study was to screening cucurbitaceous rootstock genotypes to root-knot nematodes (Meloidogyne spp.), Fusarium spp. and Pythium spp. During the period 2014-2015 in the Maritsa Vegetable Crops Research Institute, Plovdiv thirteen breeding materials belonging to Cucurbitaceae family were tested: Gergana, Kiara F1, TG, TD (Cucumis sativus); CM 720, SB-2, SB-3, Turban (C. maxima); Muskatna 51-17, Carotina, (C. moschata); Turban × Muskatna 51-17, CM 720 × Carotina (C. maxima × C. moschata F1); Local (Lagenaria siceraria). Two parallel trials were performed in greenhouse conditions. Local isolates of pests were used for the screening tests. Plants were grown in pots and inoculated with mixed infection of Fusarium spp. and Pythium spp. In trial with root-knot nematodes the plants were inoculated with 6000 second stage juveniles (J2). The response was recorded 60 days after inoculation. Results indicated that Carotina was resistant when the pots were inoculated with Meloidogyne spp. Resistant response to soil-borne pathogens possesses cucumber lines TG and TD and Lagenaria. Tested cucurbitaceous material can be used directly for grafting cucumber plants, and also be able to used as a basis for starting breeding program for rootstocks with tolerance to Meloidogyne spp., Fusarium spp. and Pythium spp.

Variability in the resistance to bacterial spot causal agents Xanthomonas euvesicatoria P and Xanthomonas vesicatoria PT2 among Bulgarian and introduced pepper varieties

T. Vancheva1, S. Masheva2*, D. Ganeva2, N. Bogatzevska3

1Biological Faculty, Sofia University, 8 Dragan Tsankov, 1164 Sofia, Bulgaria
2Vegetable Crops Research Institute Maritsa, 32 Brezovsko shose, 4000 Plovdiv, Bulgaria
3Institute of Soil Science, Agrotechnologies and Plant Protection, Nikola Pushkarov, 7 Shosse Bankya, 1331 Sofia, Bulgaria

(Manuscript received 8 September 2015; accepted for publication 26 January 2016)

Abstract. Bacterial spot in pepper (Capsicum annuum L.) is caused by Xanthomonas euvesicatoria and X. vesicatoria. The natural Bulgarian population of X. vesicatoria belongs to pepper-tomato pathotypes (PT), whereas Macedonian population of X. euvesicatoria refers to pepper pathotypes (P). Bacterial spot of pepper caused by X. vesicatoria and X. euvesicatoria has become a very serious disease in Bulgaria during the past few years. The use of resistant pepper cultivars is the most economically and technically efficient method for control. Pepper varieties with immune and/or resistant reaction were not found in this study. Moderately susceptible to both pathogens were the following varieties: Kapia UV-Vertus, Sofijska kapia and Familiya of Kapia type, Quadrato D”Asti Giallo of Dolma type and Chorbadzhiyski of long pungent fruits. All varieties with cone-shaped fruits and the ones for sweet powder performed with highly susceptible reaction to X. еuvesicatoria.


Hybridization between cultivated sunflower and wild annual species Helianthus petiolaris Nutt.

D. Valkova*, G. Georgiev, N. Nenova, V. Encheva, J. Encheva

Dobrudzha Agricultural Institute, 9520 General Toshevo, Bulgaria

Abstract. InterspecifichybridizationwascarriedoutbetweensterileanaloguesofcultivatedsunflowerlineswithnormalcytoplasmandwildannualHelianthus petiolaris accessions from a collection of DAI-General Toshevo. The obtained F1 progenies were characterized from morphological, phenological, biochemical and phytopathological point of view. Hybrid forms with resistance to leaves pathogens, downy mildew and broomrape were obtained. They were distinguished with diversity of seed oil content. The most variable phenological phases of hybrid plants from all crosses were duration of flowering period and germination. The hybrid plants from crosses 325 A x E-142 and 813 A x E-142 were characterized with higher seed oil content than the other studied crosses. All hybrid plants, originating from wild Helianthus petiolaris accession E-142 were resistant (100%) to downy mildew and to the parasite broomrape. They were also with immune type of reaction to the leaves pathogens and with the highest oil content in seeds. Among the included in the investigation accessions, E-142 was characterized with the highest crossability. The hybrid plants of the crosses included in this study were carriers of Rf genes and could be used for developing restorer lines.


Sulfo technology for multiplication of sunflower hybrids resistant to tribenuron metil-based herbicides

C. Melucă, N. Pîrvu, T. Nistor, R. Sturzu, A. Stoilova
Abstract. Certain experiments with sunflower hybrids realized through Sulfo technology, resistant to tribenuron methyl 75% based herbicides were performed at Agricultural Research and Development Station(ARDS)Teleorman, Romania. There is a response to the hypothesis that the herbicide application (4–6 real leaves) when night temperatures (after application) are lower than 12°C could provoke higher damages at green tissue level. Damages were registered of 6.5–11.8% and decreased to 0.8–5.6% when temperatures were higher than 12°C. The yielding ability of these sunflower hybrids is not affected as compared to the conventional check hybrid Favorit, its level was, on three year average, of 3652–4985 kg/ha, versus 3735 kg/ha achieved by the Favorit hybrid. It may emphasize that the hybrid Toro showed the highest gain in yield versus the check hybrid Favorit (1250 kg/ha, respectively 33.5%). The yielding ability of the hybrid Toro exceeded by 774 kg/ha (11.8%) the yield achieved by the hybrid PR 64 LE20 (Pioneer registration).


Investigation on the resistance of doubled haploid sunflower lines to some biotic factors

M. Drumeva, P. Yankov, N. Nenova, P. Shindrova
Abstract. The investigation was carried out at the Laboratory facilities of Dobrudzha Agricultural Institute (DAI), General Toshevo, Bulgaria during 2010 – 2012, and involved 15 doubled haploid fertility restorer sunflower lines (R-lines). The lines were obtained by the gamma-induced parthenogenesis method under greenhouse conditions in 2007 from three hybrid combinations developed at DAI. The resistance of the plants to downy mildew – one of the main pathogens on sunflower, and to the parasite broomrape was followed. The breeding materials were infected with downy mildew (Plasmopara halstedii), race 731, and broomrape (Orobanche cumana Wallr.) under greenhouse conditions. The evaluation for resistance was done according to a scale from 0 % (susceptible genotype) to 100 % (resistant genotype). To determine the resistance to downy mildew, standard methodology was applied, adapted for work under the specific conditions of DAI; the methodology of Panchenko (1975) was used to determine the resistance to broomrape. Four lines demonstrated complex resistance to downy mildew and broomrape. Among the other eleven lines, three lines showed 100 % resistance to downy mildew race 731, and five lines were resistant to Orobanche (races A-F).


Apricot breeding for resistance to Sharka

V. Bozhkova, S. Milusheva
Abstract. The Sharka disease caused by Plum pox virus (РРV) was found for the first time in Bulgaria more than 80 years ago and it is an endemic disease for our country, as is for all the East European countries. Like all plant viruses, PPV could not be controlled with treatments and that makes breeding of resistant cultivars and rootstocks a significant tool for limiting its spread. The investigation was carried out in the period 2009–2012 in the collection plantations of the Fruit-Growing Institute, Plovdiv in the frames of FP7 project of the EU „Sharka Containment (SharCo)”. The aim set in one of the work packages of the project was to carry out accelerated breeding activities of apricot cultivars resistant to Sharka by using MAS (marker-assisted selection). The hybridization programme included 24 parental combinations with 12 633 pollinated flowers and as a result 1661 hybrid stones (seeds) were obtained. The molecular marker analysis of the leaf samples from 39 hybrid plants obtained from 7 crossings showed that 8 of the hybrids contained a gene for resistance to PPV. Those were plants of the parental combinations ‘Harcot’ х ‘Lito’, ‘Lito’ х ‘SEO’ and ‘Harlayne’ х ‘Harcot’. Data showed that all hybrids obtained from crossing of two resistant cultivars (‘Lito’ х ‘SEO’) have a gene for resistance. If only one of the parental cultivar is resistant, part of the hybrids have gene for resistance to PPV and in our case it is 50% of all analyzed hybrids.


Status of remote hybrids in the Poaceae: problems and prospects

H. Stoyanov
Abstract. Wide hybridization as a tool of classical breeding is a method which is successfully applied in the development of breeding programs in cultural plants. Its application is a particularly effective means to overcome the effects of biotic and abiotic stress in cultural species in Poaceae. Through wide hybridization genes for resistance to phytopathogens, insect pests, tolerance to the toxicity of aluminum, copper, cadmium are successfully transferred. The method has also high efficiency in breeding with regard to cold resistance, drought tolerance, lodging, plant height. This was achieved thanks to the phylogenetic proximity of bread wheat (Triticum aestivum) with wild species as representatives of Aegilops, Haynaldia, Agropyron, Elytrigia, Elymus, Leymus. Wide hybridization is useful in order to obtain haploid plants resulting in valuable homozygous lines. The utilization of crosses as Triticum x Zea, Triticum x Imperata, Triticum x Pennisetum allows rapid elimination of the paternal chromosomes in the meiotic division. The method of wide hybridization was successfully used to combine the genomes of valuable cultivars. Thus amphidiploid cultural species as Triticale (Triticum x Secale) and Tritordeum (Triticum x Hordeum) are successfully obtained. However, wide hybridization is related to the problems of heredity. The low percentage of crossability due to incompatibility of the stigmas of maternal plants and pollen of the paternal plants set the large number of crosses that should be handled. In many crosses there are different types of genomic incompatibility – preembryonic (receiving reduced seedset), embryonic (low percentage of germination of the seeds) postembryonic (high degree of sterility of the obtained hybrids). Low viability and the hybrid necrosis is also an essential disadvantage of wide hybrids. Using techniques such as colchicine treatment, anther culture and embryo culture are means to overcome difficulties in wide hybridization and make it a promising method of breeding in the Poaceae.