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The nature and magnitude of heterosis and combining ability was studied in 18 F1 hybrids involving three CMS lines and six testers using line × tester analysis. The analysis of variance for combining ability of all the traits showed that variances due to treatments, parents, hybrids were highly significant. The line ‘CRMS 32A’ and testers viz. ‘Super rice-8’, ‘R 1099-2569-1-1’ and ‘Jitpiti’ were identified as good general combiners. The significant differences between lines x testers interaction indicates that SCA attributed heavily in the expression of these traits and demonstrates the importance of dominance or non additive variances for all the traits. The hybrid ‘CRMS 32A’/‘R 1099-2569-1-1’ and ‘APMS 6A’/‘Super rice-8’ were promising for grain yield. The magnitude of relative heterosis, heterobeltiosis and standard heterosis were also estimated for different characters. A high degree of relative heterosis was observed for grain yield (20.45- 82.37%) in the hybrids viz., ‘CRMS 32A’/‘Super rice-8’, ‘APMS 6A’/‘Super rice-8’, ‘APMS 6A’/‘Jitpiti’ and ‘CRMS 32A’/‘R 1099-2569-1-1’. While, a higher degree of: heterobeltiosis (13.60 -68.37%) was observed for grain yield in the hybrids viz., ‘CRMS 32A’/‘Super rice-8’, ‘CRMS 32A’/‘R 1099-2569-1-1’, ‘APMS 6A’/’Super rice-8’ and ‘APMS 6A’/’Jitpiti’. A high degree of standard heterosis was observed for grain yield in the hybrid ‘CRMS 32A’/‘R 1099-2569-1-1’. The hybrid ‘CRMS 32A’/ ‘R 1099-2569-1-1’ recorded a high degree of relative heterosis (62.01%), heterobeltiosis (57.35%) and standard heterosis (15.05 and 25.51% over check hybrids, ‘Mahamaya’ and ‘Indirasona’, respectively) that can be tested on yield trials for its further testing over locations.

The nature and magnitude of heterosis and combining ability was studied in 18 F1 hybrids involving three CMS lines and six testers using line × tester analysis. The analysis of variance for combining ability of all the traits showed that variances due to treatments, parents, hybrids were highly significant. The line ‘CRMS 32A’ and testers viz. ‘Super rice-8’, ‘R 1099-2569-1-1’ and ‘Jitpiti’ were identified as good general combiners. The significant differences between lines x testers interaction indicates that SCA attributed heavily in the expression of these traits and demonstrates the importance of dominance or non additive variances for all the traits. The hybrid ‘CRMS 32A’/‘R 1099-2569-1-1’ and ‘APMS 6A’/‘Super rice-8’ were promising for grain yield. The magnitude of relative heterosis, heterobeltiosis and standard heterosis were also estimated for different characters. A high degree of relative heterosis was observed for grain yield (20.45- 82.37%) in the hybrids viz., ‘CRMS 32A’/‘Super rice-8’, ‘APMS 6A’/‘Super rice-8’, ‘APMS 6A’/‘Jitpiti’ and ‘CRMS 32A’/‘R 1099-2569-1-1’. While, a higher degree of: heterobeltiosis (13.60 -68.37%) was observed for grain yield in the hybrids viz., ‘CRMS 32A’/‘Super rice-8’, ‘CRMS 32A’/‘R 1099-2569-1-1’, ‘APMS 6A’/’Super rice-8’ and ‘APMS 6A’/’Jitpiti’. A high degree of standard heterosis was observed for grain yield in the hybrid ‘CRMS 32A’/‘R 1099-2569-1-1’. The hybrid ‘CRMS 32A’/ ‘R 1099-2569-1-1’ recorded a high degree of relative heterosis (62.01%), heterobeltiosis (57.35%) and standard heterosis (15.05 and 25.51% over check hybrids, ‘Mahamaya’ and ‘Indirasona’, respectively) that can be tested on yield trials for its further testing over locations.

The F3 population of eighteen different cross combinations using five local and seven exotic genotypes was used to study the genetic parameters, heritability, correlation and path coefficients for fourteen quantitative characters under temperate conditions. The selected progenies showed highly significant difference for most of the agro-morphological characters. Comparatively high phenotypic coefficients of variation were observed for all the character than genotypic coefficient variation. High heritability (%) was recorded for days to 50% flowering (96%) followed by days to maturity (95%) and grain yield per plant (84%). High genetic advance were observed for grain yield (47%) followed by biological yield/plant (27%) and harvest index (25%). Days to 50% flowering was positively and significantly correlated with days to maturity, grain length with LB ratio flag leaf length with grain breadth and panicle length with grain breadth at genotypic level. Path coefficient analysis revealed that harvest index and biological yield has highest direct effect on yield followed by days to maturity and number of grain per panicle. Biological yield per plant has highest indirect effect on yield via days to flowering followed by grain weight via biological yield per plant, grain breadth via days to 50 % flowering and flag leaf length via biological yield per plant. Therefore, information on the genetic parameters such as coefficient of variation, heritability, genetic advance and the influence of environment on the expression of these characters will help the breeder to evolve suitable cultivars within a short time for hill ecologies.

The F3 population of eighteen different cross combinations using five local and seven exotic genotypes was used to study the genetic parameters, heritability, correlation and path coefficients for fourteen quantitative characters under temperate conditions. The selected progenies showed highly significant difference for most of the agro-morphological characters. Comparatively high phenotypic coefficients of variation were observed for all the character than genotypic coefficient variation. High heritability (%) was recorded for days to 50% flowering (96%) followed by days to maturity (95%) and grain yield per plant (84%). High genetic advance were observed for grain yield (47%) followed by biological yield/plant (27%) and harvest index (25%). Days to 50% flowering was positively and significantly correlated with days to maturity, grain length with LB ratio flag leaf length with grain breadth and panicle length with grain breadth at genotypic level. Path coefficient analysis revealed that harvest index and biological yield has highest direct effect on yield followed by days to maturity and number of grain per panicle. Biological yield per plant has highest indirect effect on yield via days to flowering followed by grain weight via biological yield per plant, grain breadth via days to 50 % flowering and flag leaf length via biological yield per plant. Therefore, information on the genetic parameters such as coefficient of variation, heritability, genetic advance and the influence of environment on the expression of these characters will help the breeder to evolve suitable cultivars within a short time for hill ecologies.

Heterosis and combining ability estimates were worked out through Line x Tester analysis of 36 hybrids developed by crossing 18 lines (Males) with two cytoplasmic male sterile (CMS) lines (Females) to know the genetic architecture of various agro-morphological traits in rice for development of hybrids under temperate conditions. Analysis of variance revealed significant differences among genotypes, crosses, lines, testers and line x tester interactions for all the studied traits. Preponderance of non-additive gene effects was realized by higher values of specific combining ability compared to general combining ability, ratio of variances of SCA to GCA and average degree of dominance. The proportional contribution of testers was observed to be lower than that of line x tester interactions thus higher estimates of SCA variances. The estimates of GCA effects indicated male parent �K-08-61-2� was good general combiner for grain yield per plant and other yield contributing traits and among the female parent �SKAU 11A� was observed to be good general combiner. Cross combinations �SKAU 7A� x �K-08-61-2�, �SKAU 7A� x �SR-2�, �SKAU 11A� x �K-08-60-2�, �SKAU 11A� x �K-08-59-3� and �SKAU 11A� x �SKAU-389� were found to be good specific combinations for grain yield per plant and other desirable traits and needs to be tested on large scale.

Heterosis and combining ability estimates were worked out through Line x Tester analysis of 36 hybrids developed by crossing 18 lines (Males) with two cytoplasmic male sterile (CMS) lines (Females) to know the genetic architecture of various agro-morphological traits in rice for development of hybrids under temperate conditions. Analysis of variance revealed significant differences among genotypes, crosses, lines, testers and line x tester interactions for all the studied traits. Preponderance of non-additive gene effects was realized by higher values of specific combining ability compared to general combining ability, ratio of variances of SCA to GCA and average degree of dominance. The proportional contribution of testers was observed to be lower than that of line x tester interactions thus higher estimates of SCA variances. The estimates of GCA effects indicated male parent K-08-61-2 was good general combiner for grain yield per plant and other yield contributing traits and among the female parent SKAU 11A was observed to be good general combiner. Cross combinations SKAU 7A x K-08-61-2, SKAU 7A x SR-2, SKAU 11A x K-08-60-2, SKAU 11A x K-08-59-3 and SKAU 11A x SKAU-389 were found to be good specific combinations for grain yield per plant and other desirable traits and needs to be tested on large scale.

The automation of sequencing technologies, flooding in the knowledge of plant-pathogen interactions and advancements in bioinformatics provide tools leading to better knowledge not only of the genome of plant pathogens or microorganism beneficial to plants but also of ways of incorporating genes from microbes into plants as microbial-derived resistance. The identification of various microorganism genes playing key role during pathogensis and the dissection of the signal transduction components of the hypersensitive response and systemic acquired resistance pathways have greatly increased the diversity of options available for tailoring fungus resistant crops. The genetically engineered plants carrying these genes showed spontaneous activation of different defense mechanisms, leading the plant in an elevated state of defense. This �defense mode� greatly enhances the plant�s ability to quickly react to a pathogen invasion and more successfully overcome the infection. The aim of this review is to highlight the dynamic use of genes of microorganisms in enhancing crop tolernace towards fungal intruders by examining the most relevant research in this field.

The automation of sequencing technologies, flooding in the knowledge of plant-pathogen interactions and advancements in bioinformatics provide tools leading to better knowledge not only of the genome of plant pathogens or microorganism beneficial to plants but also of ways of incorporating genes from microbes into plants as microbial-derived resistance. The identification of various microorganism genes playing key role during pathogensis and the dissection of the signal transduction components of the hypersensitive response and systemic acquired resistance pathways have greatly increased the diversity of options available for tailoring fungus resistant crops. The genetically engineered plants carrying these genes showed spontaneous activation of different defense mechanisms, leading the plant in an elevated state of defense. This defense mode greatly enhances the plants ability to quickly react to a pathogen invasion and more successfully overcome the infection. The aim of this review is to highlight the dynamic use of genes of microorganisms in enhancing crop tolernace towards fungal intruders by examining the most relevant research in this field.

Viral diseases are a major threat to world agriculture and breeding resistant varieties against these viruses is one of the major challenge faced by plant virologists and biotechnologists. The development of the concept of pathogen derived resistance gave rise to strategies ranging from coat protein based interference of virus propagation to RNA mediated virus gene silencing. Much progress has been achieved in protecting plants against these RNA and DNA viruses. In this review, the most recent transgene based approaches for viral disease management in plants will be discussed.

Viral diseases are a major threat to world agriculture and breeding resistant varieties against these viruses is one of the major challenge faced by plant virologists and biotechnologists. The development of the concept of pathogen derived resistance gave rise to strategies ranging from coat protein based interference of virus propagation to RNA mediated virus gene silencing. Much progress has been achieved in protecting plants against these RNA and DNA viruses. In this review, the most recent transgene based approaches for viral disease management in plants will be discussed.

Sugarcane (Saccharum officinarum L.) is an important commercial crop grown globally for its sugar-rich stalk. Low genetic variations and unwanted flowering in modern sugarcane varieties affect sugarcane quality and production. Therefore, a panel of 628 genetically diverse sugarcane clones were evaluated under field conditions at the Regional Research Station, Kapurthala, Punjab Agricultural University during 2019–20, for quality, yield and yield traits. The effect of flowering on quality and yield traits on a sub-set of 34 flowering sugarcane clones was also studied. A panel of 628 sugarcane clones showed greater genetic diversity for all the traits. HR brix per cent varied from 14–24%, number of millable cane (NMC) varied from 13–80 and single cane weight varied from 0.4–2.6 kg in 628 clones under field conditions. Non-flowering sugarcane clones’ mean performance was greater than flowering clones for most of the traits. However, no significant differences in quality traits among the clones at different flowering stages (flag leaf, tip emergence and complete flowering) were observed. Therefore, there is a huge genetic diversity in sugarcane germplasm for quality and yield traits and it should be exploited by breeding community for the development of sugarcane varieties with improved yield and better quality.

A field experiment was conducted during 2016-17 at Punjab Agricultural University, Regional Research Station, Kapurthala, Punjab, India with nine treatments comprising various combinations of farmyard manure (FYM), biofertilizers and different levels of chemical fertilizers in a randomized block design (RBD). Our results demonstrated that application of FYM @ 20 t/ha with soil test based application of nutrients recorded significantly highest number of millable canes of 134.3 thousand/ha and number of shoots (142.2 thousand/ha) at 150 DAS. However, cane length, cane diameter, single cane weight, cane yield and sugar yield were statistically at par with either application of 100% RDF plus FYM @ 20 t/ha or with the soil test based application of nutrients along with biofertilizers and 10 t/ha of FYM. With 20 t/ha of FYM and chemical fertilizer, the build-up of organic carbon content, N, P, K, Zn, Fe, Cu and Mn were significantly higher than the treatments containing either 10 t of FYM/ha or no manure. Application of FYM or biofertilizers or both along with RDF or STB nutrient application resulted in 12.8 to 17.9% higher cane yield, resulting in additional net returns of ₹ 20592 to 45230/ha as compared to recommended dose of inorganic fertilizers alone. Our study showed that higher cane and sugar productivity and economic returns can be achieved by applying either 20 t of FYM or 10 t of FYM along with bio-fertilizers.