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Gerbera is an important commercial flower crop in the world. Augmenting the genetic diversity is desirable for further improvement in Gerbera breeding programme. Thirty-seven (37) Gerbera accessions were evaluated and analysed for genetic variability, heritability, correlation and path coefficient analysis using yield and quality traits. Results showed that phenotypic coefficients were higher than genotypic coefficients of variation for all the characters. All the traits, except stalk and flower diameter, had high heritability (>60%) and genetic advance (>20%). Based on cluster analysis, the 37 accessions were grouped into seven clusters. Cluster I consists of the maximum number of genotypes (22), while clusters IV–VII are monogenotypic with unique traits. Cluster analysis (D2) showed wider genetic diversity within and between the clusters. The first four principal components (Eigenvalue >1) contributed 72.3% of the total variation. The number of leaves, number of flowers and flower stalk length contributed the most to genetic divergence. Flower yield showed a significant positive genotypic correlation with the number of leaves and suckers. The path analysis (genotypic) revealed that number of suckers, flower stalk diameter and flower stalk length contribute major positive direct effects on number of flowers. Therefore, the wide genetic variability existing in the germplasm may facilitate improvement in gerbera crops. Superior lines (RCGH-12, -22, -114, -117) with higher yield (>23 flowers/plant) and vase life (>5 days) could be promoted for commercial production under open field conditions. While RCGH 28 has a dwarf flower stalk that can be promoted for pots and decoration purposes. [ABSTRACT FROM AUTHOR]

Gerbera is an important cut flower crop popular throughout the world. In summer months of 2016, gerberas grown in polyhouses of RHREC, GKVK, Bengaluru, Karnataka, India showed heavy infestation of thrips and displayed symptoms of viral infections. Infected plants displayed irregular chlorotic or necrotic spots or blotches, necrosis of veins, bronzing, crinkling and deformations of leaves; necrotic streaks on flower stalks; chlorosis or necrosis of flower petals; tip necrosis or death of young plants. The virus was identified as groundnut bud necrosis virus based on DAC-ELISA, RT-PCR and transmission studies, and it was characterized by cloning and sequencing of N gene and 3′ UTRs. Thrips associated was identified as Scirtothrips dorsalis and the virus was detected in individual thrips using DAC-ELISA. The virus could be efficiently transmitted to cowpea variety C-152 both by mechanical sap inoculation and vector transmission and to tulsi plants by vector transmission. Sequence of S-RNA segment of the virus from two independent gerbera samples was submitted under the accession numbers KX832986.1 and KX832987.1. The two isolates showed per cent identities of 97.1 and 98.5 at N gene and at 3′ UTRs, respectively, with each other and 92.9–99.1% at N gene with other GBNV isolates. Phylogenetically they clustered along with other GBNV isolates reported from different hosts and locations within the major clade of watermelon silver mottle virus serogroup. Differential response was observed in gerbera varieties with respect to incidence of GBNV disease (19.6–80.6%) and thrips (24.6–54.0 thrips/leaf) with the least incidence in the varieties Esmara and Orinaco. [ABSTRACT FROM AUTHOR]

Gerbera (Gerbera jamesonii) is a popular ornamental plant cultivated all over the world. It is grown in beds, pots and used as cut-flower in making bouquets and for decoration in ceremonial functions. Gerbera has been commercially cultivated by a large number of growers in India as a primary source of income, therefore, has high socioeconomic impact in floriculture industry. The gerbera cultivation areas in India are increasing day by day due to its uses and the market demands. Its cultivation has been hampered by a variety of diseases that affect its flower quality and quantity. Of them, the viral and phytoplasma diseases cause considerable losses in gerbera cultivation. In this review, we have described about the disease symptoms, detection methods and identification of causal virus and phytoplasma pathogens affecting gerbera production worldwide and their disease management strategies opted by the researchers for production of pathogen-free plants. [ABSTRACT FROM AUTHOR]

Presents an abstract of the article "Occurrence of Cucumber mosaic virus in Gerbera jamesonii in India," by N. Verma, A. K. Singh and S. Kulshreshtha and published in the October 2004 issue of the "Plant Disease."