Rose balsam (Impatiens balsamina) is an important ornamental species grown worldwide for its attractive flowers and also having medicinal properties. Flat stem, little leaf, and phyllody symptoms were observed in I. balsamina nurseries in Uttar Pradesh and Tripura states of India during surveys from 2018 to 2020, with an incidence from 6 to 27%. Amplicons of ~ 1.2 kb were amplified in all the tested symptomatic samples of I. balsamina using universal phytoplasma primer pairs from different surveyed locations, but not from the asymptomatic plants. Pairwise sequence comparison, phylogeny, and virtual RFLP analysis of 16S rRNA gene sequences identified the phytoplasmas as 16SrI-B subgroup strain from Tripura (Lembucherra) and 16SrII-D subgroup strain from Uttar Pradesh (Gorakhpur and Faizabad). Phytoplasma presence and identity was further confirmed by amplifying secA, rp, secY, and tuf genes. This is the first report of 16SrI-B and 16SrII-D phytoplasmas detection in I. balsamina in the world.

Sugar recovery in a factory depends upon regular crushing and quality of varieties besides various other working parameters. Strategies for increased productivity and sugar recovery, varietal improvement can bring out through selection of parents to get maximum gains. These are governed by sugar content, fiber, rind hardness and cane yield. In order to assess the breeding value of different traits including rind hardness, study was undertaken at Sugarcane Research Institute, Shahjahanpur, during 2011-2012. Phenotypic difference and correlations among agronomic characters, basic quality characters and rind hardness in 120 segregating genotypes derived from contrast bi-parental cross (UP9530 × Co86011) of sugarcane cultivar were studied in this experiment. All the traits observed were found statistically significant among the mapping populations. The mean value of rind hardness was 5.91 with a range from 2.08 to 12.10 among 120 segregating population including their parents. Rind hardness (RHD) showed significant positive genotypic correlation with sugar yield-related traits viz; cane weight (CW, r = 0.325), cane yield (CYLD, r = 0.380) and sugar yield (SUYLD, r = 0.248). Significant negative correlation was observed for rind hardness with commercial cane sugar percent (CCS%, r = −0.388), number of millable cane (NMC, r = −0.216), hand refractometer brix %-October (HBR, r = −0.154), Brix% in juice (BR, r = −0.119) and Sucrose% in juice (SUC, r = −0.080). The simple correlation analysis showed that RHD, CW, CYLD and SUYLD showed significant positive correlation for agronomic characters, but for basic quality characters had negative correlations. Result indicated that rind hardness was found to have economically important trait due to showing significant positive and negative correlation with sugar yield and sugar content, respectively. The study also revealed that with the reduction in rind hardness, sugar recovery may increase. Present findings indicated that the rind hardness could play as a key role in the selection of elite genotypes in breeding program to develop high sugar, high yielding, erect, non-lodging, disease and insect resistant varieties. The details of the study were discussed in the manuscript.

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