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Biofirtification is one of the sustainable approaches for improving the F2 and Zn content and their bioavailability in rice grain. Screening germplasm for Fe and Zn content is the initial step of biofortificaton. Sixty accessions of rice genotypes for Fe and Zn concentration. Iron concentration ranged from 3.38 ppm to 36.99 ppm and zinc from 3.32 ppm to 42.49 ppm. Genotypes having high Fe and Zn content are selected for further breeding programme.

The development of nutrient-use efficient rice lines is a priority amidst the changing climate and depleting resources viz., water, land, and labor for achieving sustainability in rice cultivation. Along with the traditional transplanted irrigated system of cultivation, the dry direct-seeded aerobic system is gaining ground nationwide. The root-related traits play a crucial role in nutrient acquisition, adaptation and need to be concentrated along with the yield-attributing traits. We phenotyped an association panel of 118 rice lines for seedling vigour index (SVI) traits at 14 and 21 days after sowing (DAS), root-related traits at panicle initiation (PI) stage in polythene bags under controlled aerobic condition, yield and yield-related traits under the irrigated condition at ICARIIRR, Hyderabad, Telangana; irrigated and aerobic conditions at ARS, Dhadesugur, Raichur, Karnataka. The panel was genotyped using simple sequence repeats (SSR) markers and genome-wide association studies were conducted for identifying marker-trait associations (MTAs). Significant correlations were recorded for root length, root dry weight with SVI, root volume at the PI stage, number of productive tillers per plant, spikelet fertility, the total number of grains per panicle with grain yield per plant under irrigated conditions, and the total number of grains per panicle with grain yield per plant under aerobic condition. The panel was divided into three sub-groups (K = 3) and correlated with the principal component analysis. The maximum number of MTAs were found on chromosomes 2, 3, and 12 with considerable phenotypic variability. Consistent MTAs were recorded for SVI traits at 14 and 21 DAS (RM25310, RM80, RM22961, RM1385), yield traits under irrigated conditions (RM2584, RM5179, RM410, RM20698, RM14753) across years at ICAR-IIRR, grain yield per plant (RM22961, RM1146) under the aerobic condition, grain yield per plant at irrigated ICAR-IIRR and SVI (RM5501), root traits at PI stage (RM2584, RM80, RM410, RM1146, RM18472). Functionally relevant genes near the MTAs through in-silico expression analysis in root and panicle tissues viz., HBF2 bZIP transcription factor, WD40 repeat-like domain, OsPILS6a auxin efflux carrier, WRKY108, OsSCP42, OsMADS80, nodulin-like domain-containing protein, amino acid transporter using various rice expression databases were identified. The identified MTAs and rice lines having high SVI traits (Langphou, TI-128, Mouli, TI-124, JBB-631-1), high yield under aerobic (Phouren, NPK-43, JBB-684, Ratnamudi, TI-112), irrigated conditions (KR-209, KR-262, Phouren, Keibi-Phou, TI-17), robust root traits like root length (MoirangPhou-Angouba, Wangoo-Phou, JBB-661, Dissi, NPK-45), root volume (Ratnachudi, KJ-221, Mow, Heimang-Phou, PUP-229) can be further employed in breeding programs for the targeted environments aimed at improving seedling vigour, yield-related traits under irrigated condition, aerobic condition as adaptability to water-saving technology. [ABSTRACT FROM AUTHOR]

Background: Association of several morphological traits such as trichome length and trichome density on the pod surface have been found to influence host plant resistance to insect pests. Genetic diversity analysis is used to identify the divergent genotypes and to utilize these genotypes to exploit heterosis. Further, morphological characters are stable across environments owing to oligogeneic nature, they serve as morphological markers in breeding which can be used in varietal or genotypic identification, varietal purification and even in seed production. Hence, the current study aimed to investigate on host plant resistance using portable paper microscope 'foldscope', genetic diversity and morphological characters. Methods: A total of 154 germplasm lines with three checks were evaluated in augmented block design (ABD) at Zonal Agricultural Research Station (ZARS), Kalaburagi, during kharif, 2018 to study their genetic diversity. Trichome length and trichome density were recorded using 'foldscope' 75 randomly selected genotypes, then correlated with shrivelled seed yield per plot due to pod fly incidence. Morphological characterization of 14 qualitative traits were recorded. Result: Grouping of 157 germplasm lines into twelve clusters indicated a wider genetic diversity for the traits studied, of which 7 clusters were solitary with one entry each. The genotypes with more trichome density and length had less damage by the pod fly. Large variations for morphological characters was observed among the genotypes for qualitative traits such as pod colour, stem colour, flower colour, seed morphology and pod trichomes. [ABSTRACT FROM AUTHOR]

The material for study of genotype x environment (G x E) interaction comprised of 23 genotypes, which were tested in four environments, during kharif-2012 and 2013 at two locations in Agricultural Research Station, Kalaburagi and Raddevadgi located in north eastern dry zone (Zone 2) of Karnataka. The experiment was laid out in lattice design with two replications. Highly significant differences among genotypes were observed for all the characters except number of pods per plant and yield per plant. Environmental +(Genotype x Environment) interaction was significant for days to 50 per cent flowering, day to maturity, plant height, pod bearing length, number of pods per plant and seed yield per plant. The variance due to pooled deviation was highly significant for all the characters which reflect the presence of sufficient genetic variability in the material. Stability parameters for seed yield per plant indicated that ASHA(ch) was stable and desirable, followed by RVK-275 and GRG-811 which were specifically adopted for favourable and poor environments respectively. Two years of field screening for Fusarium wilt (FW) and Sterility Mosaic Disease (SMD) yielded three genotypes viz., GRG-811, GRG-2009 and ASHA for resistance to Fusarium wilt and moderate resistance to SMD. Hence, these genotypes can be used directly as a variety or choice of parent for hybridization programme. [ABSTRACT FROM AUTHOR]

The restorer lines are used to get fertile hybrids in hybrid seed production system of sunflower. Improvement of R-lines for fertility and oil content of sunflower is required to get desirable hybrids upon crossing. In the present study, 6 restorer lines were crossed in full diallele and both direct and reciprocal crosses along with parents were evaluated for their combining ability. The analysis of variance revealed higher magnitude of SCA variance than GCA variance for all the characters studied except for days to 50 per cent flowering. Among six parents, GMU -520 and R-GM-41 were best general combiner for plant height, head diameter, test weight and leaf size in the desired direction. However, GMU-520 has advantage of yield per plant and oil content. From 15 direct crosses R-GM-41 x R -GM-49 exhibited significant specific combining ability for viz., days to 50 per cent flowering (-1.08), plant height (13.69), head diameter (4.79), leaf size (0.74), yield per plant (17.14), volume weight (2.54), test weight (1.75) and oil content (0.34) followed by RCR-630 x GMU-520, R-GM-41 x EC-602060, R-GM-49 x GMU-520 and EC-602060 x GMU-520 each exhibiting good specific combining ability for majority of characters. Among reciprocal crosses R-GM -41 x RCR-8 exhibited a high reciprocal effects for head diameter (4.57), yield per plant (15.16), test weight (2.02) and leaf size (0.75). [ABSTRACT FROM AUTHOR]

The present investigation was carried out during kharif 2012 at the Agricultural Research Station, Gulbarga and other four locations located in north eastern dry zone (Zone 2) of Karnataka, to know the stability of the nineteen advanced genotypes of pigeonpea. Highly significant differences among genotypes were observed for all the characters except number of pods per plant, number of seeds per pod and seed yield per plant. The variance due to Genotype x Environment found significant for the characters like days to 80% pod maturity and number of seeds per pod. Environment (linear) interaction component was significant for all the traits. The variance due to pooled deviation (non- linear) was highly significant for all the characters except for number of seeds per pod which reflect considerable genetic diversity in the material. Out of 19 genotypes studied two entries viz., GRG-109 and GRG-107 were consistent and high yielding compared to local checks. [ABSTRACT FROM AUTHOR]