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Rice is the most important food crop both in value and volume for the Asian population. Frequent drought, flood and salinity stresses exacerbated by global climate change adversely affect rice production in more than fifty percent of the rice growing areas. Green revolution high yielding varieties carrying sd1 dwarfing gene have almost fully replaced the traditional climate resilient landraces and varieties of rice. However, these were bred primarily for yield under high input conditions and therefore are sensitive to adverse climatic conditions. Hence, there is urgent need to combine the high productivity with climate resilience. Knowledge of rice genome and genes for tolerance to different abiotic stresses provided us an opportunity to transfer favorable alleles of these genes into high yielding varieties through genomics-assisted backcross breeding through multi-institutional networks. Six consistent genomic regions (QTLs) for grain yield under drought; namely qDTY1.1, qDTY2.1, qDTY2.2, qDTY3.1, qDTY3.2 and qDTY12.1 have been transferred to flood tolerant versions of mega varieties of rice, Swarna, Samba Mahsuri and IR 64. To address the problem of flash flooding qSUB1 QTL has been transferred to nine popular rice varieties, namely ADT 46, Bahadur, Ranjit, HUR 105, Sarjoo 52, Pooja, Pratikshya MTU 1075 and Rajendra Mahsuri. Further, qSALTOL1 QTL for seedling stage salt tolerance and qSSISFH8.1 for reproductive stage salt tolerance have been transferred to six popular rice varieties, ADT 45, Gayatri, MTU 1010, PR 114, Pusa 44 and Sarjoo 52. We used foreground selection markers for the presence of desired gene/QTL and recombinant selection markers for reduction of linkage drag around these genes. Genotypic background selection was done after BC3F3 stage using a 50K SNP chip on a set of 20 advance lines obtained by phenotypic selection for closeness to the recipient parents. Near-isogenic lines (NILs) with more than 95% similarity to the recipient parent genome have been released and notified for commercial cultivation and are gaining fast popularity. These climate smart rice varieties will provide production stability in the adverse ecologies and support farmer’s income and livelihood.

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Whitefly (Bemisia tabaci Gennadius) is a hemipteran phyto polyphagous sucking insect pest which is an important pest of cotton that causes economic losses to the crop by reducing its yield and quality. Ecdysteroids such as 20-hydroxy ecdysone (20-E), play a significant role in larval moulting, development, and reproduction in pterygota insects. Receptor of 20-E, that is Ecdysone Receptor (BtEcR) of Bemisia tabaci has been targeted to prevent fundamental developmental processes. To identify potent inhibitors of BtEcr, 98,072 natural compounds were retrieved from ZINC database. A structure-based virtual screening of these compounds was performed for evaluating their binding affinity to BtEcR, and top two compounds (ZINC08952607 and ZINC04264850) selected based on lowest binding energy. Molecular dynamics simulation (MDS) study was performed for analyzing the dynamics and stability of BtEcR and top-scoring ligand-BtEcR complexes at 50 ns. Besides, g_mmpbsa tool was also used to calculate and analyse the binding free energy of BtEcR-ligand complexes. Compounds ZINC08952607 and ZINC04264850 had shown a binding free energy of −170.156 kJ mol-1 and −200.349 kJ mol-1 in complex with BtEcR respectively. Thus, these compounds can be utilized as lead for the development of environmentally safe insecticides against the whitefly.

Lodging of the rice crop is the major limiting factor to rice productivity in cyclone prone areas. Lodging not only reduces the yield but also it deteriorates grain quality impedes mechanical harvesting, increases harvesting and drying costs. Lodging resistance is complex trait influenced by environment and structural properties of the stem. Factors like cultivar, fertilizers application, irrigation, plant density, pest and disease management influences lodging apart from weather parameters. Though semi dwarf gene reduced lodging to certain extent but it resulted in yield plateau and also high yielding semi dwarf rice varieties like Swarna prone to lodging because of weak culm. Breeding for lodging resistant rice varieties is important strategy to combat adverse effects of climatic changed conditions. Direct selection for lodging resistance by visual score in segregating material is herculean task as it is influenced by structural properties of the stem and weather parameters. Type of lodging decides selection of traits suitable for lodging resistance. Stem lodging is the main type of lodging limits the rice productivity in irrigated ecosystem. This review focused on understanding the problems of lodging, effects of lodging, factors influencing lodging resistance, physiological basis of lodging, breeding for lodging resistance and Quantitative trait loci (QTLs) associated with lodging resistance related traits. Root lodging prevails under direct seeded condition where root anchorage is poor. Selection suitable phenotypic traits and genotyping with suitable molecular markers would help in framing suitable breeding strategy for the development of lodging resistant rice varieties.