Red rot is a serious disease of sugarcane caused by the fungus Colletotrichum falcatum that has a colossal damage potential. The fungus, prevalent mainly in the Indian sub-continent, keeps on producing new pathogenic strains leading to breakdown of resistance in newly released varieties and hence the deployment of linked markers for marker-assisted selection for resistance to this disease can fine tune the breeding programme. This study based on a panel of 119 sugarcane genotypes fingerprinted for 944 SSR alleles was undertaken with an aim to identify marker-trait associations (MTAs) for resistance to red rot. Mixed linear model containing population structure and kinship as co-factor detected four MTAs that were able to explain 10-16 % of the trait variation, individually. Among the four MTAs, EST sequences diagnostic of three could be BLAST searched to the sorghum genome with significant sequence homology. Several genes encoding important plant defence related proteins, viz., cytochrome P450, Glycerol-3-phosphate transporter-1, MAP Kinase-4, Serine/threonine-protein kinase, Ring finger domain protein and others were localized to the vicinity of these MTAs. These positional candidate genes are worth of further investigation and possibly these could contribute directly to red rot resistance, and may find a potential application in marker-assisted sugarcane breeding.

Culmicolus smut (Sporisorium scitamineum Meike), the sett borne pathogen causes considerable loss to sugarcane productivity especially to ratoon crop. Use of fungicides may cause environmental hazards besides residual problem. Therefore, twenty five plant species and Trichoderma viride was evaluated in vitro against smut pathogen (Sporisorium scitamineum). Out of twenty five plant species, leaf extracts (10%) of Calendula officinalis, Solanum nigrum and culture filtrate (5%) T. viride (bioagent) inhibited mycelial growth and teliospore germination of S. scitemineum. In plant crop, smut incidence was 2.07% in dipping of infected setts in leaf extract of S. nigrum before planting, while in remaining treatments it ranged between 3.38 to 7.28% as against 11.3% in control. In ratoon crop, the smut incidence was 5.38% in the same treatment, while in rest of the treatments it ranged between 6.85 to 9.94 per cent as against 15.3% in control. However, sett treatment with T. viride culture filtrate (5.0%) was superior among all the treatments as it improved germination (6.2%), millable canes (27.33%) and cane cane yield (38.18%) in plant crop and sprouting of clumps (12.57%), millable canes (51.46%) and yield (48.75%) in ratoon crop, respectively.

Saccharum officinarum is one of the most cultivated hybrid varieties among the sugarcane varieties. In sugarcane plant sucrose is the major carbohydrate which can be stored and transported. Different physiological and biochemical studies on this crop report that invertase activity and sucrose concentration some how are key limiting step in the process of sucrose accumulation. Significant efforts have been made in relation to the sucrose cycle by altering the sucrose phosphate synthetase, sucrose synthetase and invertase. In sugarcane two types of invertase enzymes have been reported on the basis of pH and cellular localization. Invertase breaks the sucrose into hexoses as a source of energy and carbon. It has also been reported that this enzyme is involved in the process of cell differentiation and plant development. Progress has been made for the understanding of invertase activity and its role in sugarcane plant. With the help of biotechnology it is possible to target the desired gene with genetic engineering approach to increase sucrose content by careful manipulation of invertase (enzyme) gene to increase the sucrose yield in sugarcane. Purpose of this mini review is to high-light the role of invertase in sugarcane and how to overcome sucrose recovery in sugarcane.

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Field experiments were conducted during 2006-07 and 2007-08 crop seasons at IISR institute farm, Lucknow to find out the impact of Integrated Disease Management (IDM) practices over Non-Integrated Disease Management (NIDM)i.e. normal package of practices of cane cultivation on red rot incidence, yield and quality parameters of sugarcane in plant and ratoon crops of moderately susceptible variety CoSe 92423. It was observed that in both plant and ratoon, IDM practices reduced red rot incidence, enhanced growth parameters and quality attributes of sugarcane compared to NIDM practices. In plant crop of IDM practices, germination was improved by 6.29%, tiller counts (16.93%); millable canes (4.90%); yield (13.09%); juice extraction (2.33%); pol % juice (0.46%); purity (0.88%), CCS (16.47%), plant height (8.90%), cane girth (13.52%); internodes (12.67%); internodal length (3.00%) and cane weight (34.04%) over NIDM practices. In ratoon crop, improvement in clump emergence (30.0%), height of cane (14.76%), cane girth (7.66%), internodes (5.31%); internodal length (14.04%); cane weight (18.90%); juice extraction (5.56%); pol % juice (0.84%); purity (2.12%), CCS t/ha (22.42%), tiller counts (19.77%), millable canes (12.09%) and yield (18.38%) was observed in IDM over NIDM practices. Thus, this study revealed that use of T. viride is beneficial for controlling red rot, improving quality attributes, enhancing yield and shelf life of a moderately red rot susceptible variety.