BEAN COMMON MOSAIC VIRUS (BCMV), BEAN COMMON MOSAIC necrosis VIRUS (BCMNV) and Cucumber MOSAIC VIRUS (CMV) are seed-borne VIRUSes in BEANs causing severe damage and reduction of yield and quality of this crop. Since there are lots of reports on the occurrence of mixed infection of BCMV, BCMNV and CMV, thus setting up an accurate, reliable and rapid method for detecting of these VIRUSes in BEAN crops could play an important role in prevention of their spread and damages and also screening of healthy plants. For this purpose, in the present study, we tried to set up a multiplex RT-PCR for simultaneous detection of BCMV, BCMNV and CMV as well as an internal control gene, 18S rRNA. To do this end, the infection of BEAN plants to above mentioned VIRUSes was confirmed by DAC-ELISA. Following total RNA extraction, cDNA was synthesized using random hexamer primers. cDNA fragments were successfully amplified using specific primers in expected sizes as almost 470 bp for BCMV, 500bp for internal control, 704 bp for BCMNV and 870 bp for CMV, respectively. The results of this study showed that this method is capable of detecting BCMV, BCMNV and CMV in 100 ng of total RNA.

To study the effect of BEAN COMMON MOSAIC VIRUS (BCMV) on seed yield, yield components and some morphological and phenological traits of BEAN genotypes, an experiment was conducted in research farm of the Islamic Azad University, Shiraz Branch in 2007. Twenty five COMMON BEAN genotypes were sown in two separate randomized complete block design with three replications under BCMV infection and non-infection conditions. The VIRUS was provided from a research farm in Yasuj. The characterization of the VIRUS was confirmed by PTA-ELISA method. After proliferation of VIRUS on susceptible cultivar, seedlings were inoculated by the leaf rub method. The leaves were dusted with carborundum powder before inoculation. Founded stress by this VIRUS did not affect the reproduction period, but vegetative period decreased a little. The results indicated that VIRUS stress has severely increased the empty pods (88.4%) and decreased seed yield by 46.76 percent, but no significant differences were observed for phenological phases. Pod length, number of seed per plant, number of seed per pod, number of empty pods, seed yield and harvest index were mostly affected by VIRUS. On the basis of the results obtained, for breeding of resistant cultivar to BCMV, in addition to yield, special attention should be paid to these traits.

In order to study cause and effect of seed yield with some agronomical traits in BEAN genotypes, two experiments were conducted under field conditions. Twenty five COMMON BEAN genotypes were sown in 2 separate RCB design with three replications under noninfected and infected conditions. First, phenotypic correlation coefficient of traits with each other was counted. At non-infected conditions number of secondary stem, harvest index, reproduction period and under infected conditions number of seeds in plant, number of seeds in pod and harvest index showed significant correlation with seed yield at 0.05 & 0.01 probability levels. Stepwise regression and then path analysis were used to determine the traits that were effective on seed yield. In stepwise regression analysis seed yield was the dependent and other traits were as independent variables. At non-infected conditions number of secondary stem, harvest index and main stem length were entered in regression model respectively and explained 84% of seed yield variations. In this manner, under infected conditions, harvest index, plant weight and number of seeds in pod justified 93% of seed yield variations. On the basis of achieved results, harvest index was introduced as profitable selection index at non-infected and infected conditions. In order to results of path analysis after harvest index at non-infected conditions number of secondary stem and at infected conditions number of seeds in pod were introduced as suitable indices.

In order to evaluate heritability and gene action for resistance to BEAN COMMON MOSAIC VIRUS (BCMV) four crosses were established among BEAN genotypes with various resistances to BCMV. All four crosses were extended by other generations-F1, F2, backcrosses- to establish four families. Four separate experiments were conducted in RCB design with 3 replications in greenhouse conditions. Inoculation was accomplished 2 weeks after sowing and sampling for ELISA test were performed 3 weeks after inoculation. Studies on the inheritance of resistance to BCMV using generation mean analysis and generation variance analysis indicated that additive components and epistasis ([i], [l]) play a major role in these crosses. Also, average broadsense and narrowsense heritabilities were 0.77 and 0.64 respectively. These data were showed importance of additive components for this trait. Therefore, selection for high resistance in breeding projects about this trait could be effective.

This experiment was conducted to determine COMMON BEAN genotypes reaction to BEAN COMMON MOSAIC Necrosis VIRUS (BCMNV). Twenty five COMMON BEAN genotypes were obtained from National BEAN Research Station of Khomein. These genotypes were planted using randomized complete block design with three replications, and inoculated with inoculums of VIRUS in greenhouse conditions in 2009. The reactions of plants were examined twenty one days after planting using ELISA test and IC-RT-PCR and visual methods. Measured traits in this research included: leaf infection (actual infection), MOSAIC leaf, systemic necrosis, vein strip, chlorotic spot and leaf shape. Quality traits (except leaf infection) were assessed by visual ranking method (visual symptom). Results indicated that genotypes were significantly different in leaf infection (actual infection), leaf MOSAIC, systemic necrosis and leaf shape. Results also showed that Ks-21189, Ks-21481 and Derakhshan were susceptible and COS16, Goli and Ks-41128 were resistant genotypes. Systemic necrosis had positive and highly significant correlation (r=0.638**) with leaf infection. Results of cluster analysis also indicated that Ks-21189 and COS16 as sensitive and resistance genotypes, respectively. Chi-square test indicated that white genotypes were more resistant than pinto and red genotypes. IC-RT-PCR results indicated that BCMNV VIRUS was present in Ks-21189 genotype.

BEAN COMMON MOSAIC VIRUS (BCMV) is a species of the genus PotyVIRUS. The genomes of potyVIRUSes consist of a single, positive-sense RNA. A VIRUS-encoded protein, VPg, is covalently linked to the 5’ end of the genomic RNA and the 3’ end is polyadenylated. The potyVIRUS genome is approximately 10,000 nucleotides with a single large open reading frame flanked by 5’ and 3’ untranslated regions. The open reading frame is translated as a large polyprotein, which is processed by three VIRUS-encoded proteases.

Aim and Background: Several VIRUSes so far have been reported to be the cause of MOSAIC and yield losses in French BEAN (Phaseolus vulgaris L.) in Iran. Among these, BCMV, and BCMNV are more important. During a growing season, French BEAN plant samples were selected with various symptoms of MOSAIC, vein clearing, leaf rolling, leaf and stem necrosis were collected from BEAN cultivation fields.Materials and methods: The samples were tested serologically against the two VIRUSes using DAS-ELISA and Tissue blot technique with the specific polyclonal antisera obtained from commercial sources. To confirm the Elisa results, selected Elisa positive samples tested applying IC- RT-PCR using VIRUS specific polyclonal antibody and a specific set of primers designed from VIRUS cp-genes region.Results: The cDNA obtained were multiplied in termocycler machine. The results of agarose gel electrophoresis of approx. 373bp and 683bp band were obtained for part of the cp genes of BCMV and BCMNV. Using IC-RT-PCT both VIRUSes were identified from samples of Arak, Neishabour, Zanjan and Karaj provinces.Conclusion: BCMV and BCMNV are widespread in almost all BEAN growing regions of Iran and often present in mixture. IC-RT-PCR test for diagnosis and identification of these two VIRUSes is proved to be more sensitive than Elisa test. In this technique combination of a specific antisera and a specific set of primers help in distinguishing the two VIRUSes in mixture.