جستجوی مقالات مرتبط با کلیدواژه « fusarium wilt » در نشریات گروه « زراعت »

Fusarium wilt (FW) caused by F. oxysporum f. sp. ciceris causes extensive damage to chickpea in many parts of the Iran. The technique of Marker-assisted backcrossing (MABC) is one of the effective and accurate methods in transferring specific genes such as disease resistance genes in a short time in self-pollination plants. Hashem is one of Iranian chickpea cultivars with high yield, plant height and tall stems which its cultivation is limited due to susceptibility to the fusarium wilt. Therefore, Purpose of this study was to introgression resistance to fusarium wilt from Ana cultivar, as a donor, to Hashem as a recurrent and susceptible cultivar using molecular marker-assisted backcrossing.

This research was conducted during five cropping seasons (2018-2023). Crossing was done between the selected parents of chickpea cultivar Ana (as a donor parent) and Hashem (as a recurrent parent) and the F1 progeny was backcrossed with Hashem to produce the BC1F1 generation. By using three backcrosses and one rounds of selfing, BC3F2 progeny was obtained. Foreground selection (FGS) was conducted with four markers (TA59, TA96, TR19, and CaM1402) linked to FW resistance genes. Background selection (BGS) was employed with evenly distributed 16 (Ana × Hashem) SSR markers in the chickpea genome to select plant(s) with higher recurrent parent genome (RPG) recovery. Finally, the selected lines of BC3F2 generation were phenotypically evaluated in terms of Fusarium disease resistance.

In first year, from the crossing of two parents, 20 real F1 plants were obtained and backcrossed with Hashem to produce BC1F1 plants. Based on results of foreground selection (FGS), was undertaken using four markers (TA59, TA96, TR19, and CaM1402) linked to resistance genes, 6 BC1F1 plants contained 4 resistant alleles and participated in the second backcrossing to produce BC2F1 plants. In the following, from a total of 52 BC2F1 plants 12 BC2F1 plants contained 4 resistant alleles, for background selection (BGS) to observe the recovery of recurrent parent genome using 16 SSRs, At this stage based on the BGS results 5 plant, with the highest background recovery, selected and backcrossed with recurrent parent to produce BC3F1 plants. Followed by cycles of, 6 plants in BC3F1 containing resistant genes and most similar to the recurrent parent were selected. The identified plants were selfed to obtain 6 BC3F2 lines which were screened phenotypically for resistance to fusarium wilt. Finally, 12 BC3F2 lines were obtained which led to identification of 3 highly resistant lines of Hashem with FWR gene introgressed in them. Also, in this study using Meta-QTL analysis region associated with genetic resistance to different race of fusarium wilt were identified on chromosomes 2, 4, 5 and 6.

Lentil cultivar Sepehr was first introduced as FLIP 2005-53L line through LIDTN-L-08 ICARDA international nursery and was evaluated in Gachsaran and Maragheh stations in 2007-2008 cropping season. FLIP 2005-53L line in the cropping seasons 2008-2009 and 2009-2010 was evaluated in the preliminary and advanced yield trials in Gachsaran and Khorramabad research stations. After evaluating the results of advanced experiments, this line was selected to participate in the national uniform regional yield trial (2010-2013) in Gachsaran, Khorramabad, Gonbad and Moghan research stations. Stability analysis of genotypes grain yield in this experiment showed that this line had the lowest contribution in the interaction of genotype × environment using different statistical methods and also it had the lowest mean rank values ​​for non-parametric stability parameters as well as 19% increases in the grain yield (with grain yield of 1166 kgha-1) ‌ compared to the control cultivar Gachsaran (with grain yield of 978 kgha-1) and therefore can be considered as "one of the most stable genotypes" with high grain yield. FLIP 2005-53L line with average grain yield of 1902 kgha-1 in farmers field in the research-extension trials, had a 15% advantage of grain yield over control cultivar Gachsaran with grain yield of 1651 kgha-1. In addition to high grain yield, good yield stability, high resistance to fusarium disease, desirable 100-seed weight (4.2 g) and suitable plant type and plant height for machine harvesting were other reasons for releasing Sepehr cultivar. Sepehr cultivar is suitable for cultivation in subtropical regions of the country including Khuzestan, Fars, Kohgiluyeh and Boyer-Ahmad, Lorestan, Kermanshah, Ardabil (Moghan) and Ilam provinces.

Fusarium wilt is considered as the second important pathogen of chickpea. Annual yield reduction caused by the disease has been estimated 10-90%. The ability of the pathogen to survive in soil for several years, even without the host, makes the control of disease very difficult. However, using chickpea cultivars that are resistant to fusarium wilt is the most effective and environment friendly method. In the present study, molecular markers (RAPD and SCAR) were used to identify chickpea genotypes containing the resistance genes to races of 1, 2, 3, 4 and 5. Genomic DNA was extracted using CTAB method from 42 chickpea genotypes. Then, polymerase chain reaction was carried out using CS-27 and CS-27700 molecular markers. Results showed that out of the 42 genotypes, 41 ones were susceptible to all the five tested races which had no resistance gene. Only Flip 06-152c line was resistant to these five races. The results of phenotypic resistance evaluation of genotypes under greenhouse condition confirmed the results of molecular evaluations.

Fusarium wilt of chickpea, caused by Fusarium oxysporum f. sp. ciceris, is one of the most important diseases of this plant in Iran. In order to control this disease biologically, fluorescent pseudomonas were isolated from the rhizosphere of chickpea plants and enumerated using King’S medium B (KB). Antifungal activity of 80 bacterial isolates against Fusarium oxysporum f. sp. ciceris was evaluated on KB and potato dextrose agar (PDA) media. Results revealed that from 80 isolates tested, 81. 25% of isolates in KB and 94. 37% in PDA showed the ability to inhibit fungal growth. There was a correlation between production of antifungal metabolites and disease reduction, however, no correlation was observed between Siderophore production and metabolite production. Under greenhouse conditions, results showed that only M2-15 isolate reduced Fusarium wilt of chickpea significantly, with the rest having positive effects on chickpea growth factors. In greenhouse experiment, M2-15، Pf-5 and K-15 isolates caused a significant increase in growth factors including dry and fresh root and shoot weights compared to control plants. Among isolates studied in this research, M2-15 decreased the severity of chickpea wilt under greenhouse conditions, significantly.

Fusarium wilt of lettuce caused by the fungus Fusarium oxysporum f.sp. lactucum is a destructive disease of lettuce in fields of Tehran province. A glasshouse experiment was conducted to evaluate resistance and susceptibility of 20 lettuce cultivars obtained from, Denmark, Italy, England, USA and Iran to an aggressive isolate of the pathogen. The Index of percentage of seed germination, number of healthy plants, fresh and dry weight of shoots and dry weight of roots were used for cultivar evaluation. Results indicated that Salinas and Grand Rapids were the most resisitant cultivars base on the mentioned index (P < 0.05). In the field experiment nine cultivars were planted in soil with 30% infection during the previous year. A Randomized Complete Block Design with four replications was used. Plants were inoculated around the roots at the two leaf stage with spore suspension of the pathogen isolate. Results indicated that local cultivars curl Ahwazi and Esfahani with no infection were resistant. Black Shahre-Ray and King Crown with 18.42% and 26.2% of infection respectively, showed an intermediate reaction to the pathogen.