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Kodo millet is one of the underutilized lost crops that has renowned nutritional and climate resilient traits. As a gluten free nutricereal, it is now being consumed in a fashion similar to that of rice and several value-added products are arising in the market day by day. Hence, this study on variability and correlation in M4 mutants have been carried out to favor superior varietal development in kodo millet to sustain nutritional security in future. In this study, around 635 M4 mutants were evaluated during Kharif 2019 on Millet Breeding Station of Coimbatore (India), with thirteen morphological traits. Among all, high PCV and GCV values were observed in plant height, panicle length, flag leaf length, seeds per panicle, culm thickness and seed yield. This presented the presence of genetic variability in the population. The prospects of effective selection with high heritability and genetic advance were exhibited by plant height, panicle length, panicle branches, flag leaf length, flag leaf breadth, seeds per panicle, stomatal number, chlorophyll index, culm thickness and seed yield per plant due to the presence of additive gene action. The correlation among traits towards yield revealed the significant positive correlation of all traits except for culm thickness and the highest associated traits were seeds per panicle and number of panicle branches. Therefore, these traits could be further focused for selection and improvement of yield in successive generations and other kodo breeding programs.

Aims: To identify the potential genotypes and the important traits for drought tolerance based on root system architectural traits and morphometric traits that can be used as a selection criteria in future crop improvement programs. Study Design: Completely randomized design for root system architectural traits and Randomized block design with two replications for morphometric traits. Place and Duration of Study: Department of Millets, Tamil Nadu Agricultural University, Coimbatore during Summer 2022. Methodology: The 33 elite genotypes were raised in polybags with two factors, one is genotype and other is treatment for observing root system architectural traits in completely randomized design. Also these genotypes were raised in the field in randomized block design with two treatments, irrigated and drought at early stage of the crop for observing morphometric traits. Results: Based on root system architectural traits, the significant traits were network perimeter, network surface area, network length and network volume. Under irrigated and drought condition, high phenotypic coefficient of variation and high genotypic coefficient of variation were observed for single plant yield, high heritability and high genetic advance for days to 50 per cent flowering, plant height, leaf blade length, spike length, 1000 seed weight and single plant yield. Correlation study revealed that all the characters except number of tillers and days to 50 per cent flowering had positive significant correlation with single plant yield. Path analysis showed that spike length had positive direct effect on single plant yield. Conclusion: The identified traits for drought tolerance were network perimeter, network surface area, network length, network volume, days to 50 per cent flowering, plant height, leaf blade length, spike length, 1000 seed weight and single plant yield. The identified drought tolerant genotypes were Nattu cumbu, ICMB 10444, 86M38 and PT 6752.

The study was commenced in a compulsion toaccomplish a successful approach in developing a commercially viable polyploidy variety in Jasminum sambac. Rooted cuttings of J. sambac cv. Ramanathapuram Gundumalli were treated with different concentrations of colchicine (0.05%, 0.10%, 0.15%, 0.20% and 0.25%) for 48 hours. The survival and sprouting rates for the different treatments were determined after 45 days of treatment and the phenotypic and stomatal characteristics of the treated plants were recorded. Colchicine treatments registered reduction in plant height (76.00 cm to 27.33 cm), internodal length (3.88 cm to 2.64 cm) and number of flowering cymes per plant (56.33 to 20.44) in comparison with the control. In comparison to untreated plants, polyploidy-induced plants developed leaves with larger stomata and lower stomatal frequency.

Aims: To evaluate the effect of various levels and methods of zinc fertilization in improving the growth and yield of barnyard millet at different growth stages. Study Design: Randomized Block Design (RBD) with three replications. Place and Duration of Study: A field experiment was conducted in the farmer’s field at Pasur village, Coimbatore district from January to April, 2022. Methodology: A field experiment was conducted with barnyard millet (Echinochloa frumentacea L.) var. MDU 1 by using different levels of ZnSO4 at 5, 10, 15, 20 and 25 kg ha-1 as basal soil application and foliar spraying of 0.25, 0.50 & 0.75% twice along with soil test based NPK as control in Randomized Block Design with three replications. The growth and yield parameters such as plant height, SPAD index, root length, lateral root length, root volume, no. of tillers, panicle length, panicle weight, 1000 grain weight, grain and straw yield were recorded as per standard protocols. Results: Application of soil test based NPK + 20 kg ZnSO4 ha-1 performed better in increasing the plant height (157.0 cm), SPAD index (46.3), root length (21.1 cm), lateral root length (16.3 cm), root volume (3.80 cc) and yield attributes like number of tillers (5.06), panicle length (17.6 cm), panicle weight (29.2 g) and 1000 seed weight (3.89g) of barnyard millet. Higher grain (2606 kg ha-1) and straw yield (3411 kg ha-1) was also registered with the addition of soil test based NPK+20 kg ZnSO4 ha-1 which was 27.1% increase over NPK. Conclusion: Basal soil application of soil test based NPK + 20 kg ZnSO4 ha‑1 was found optimal and economical for improving the growth and yield of barnyard millet variety MDU 1.

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an invasive insect pest of India native to the Western Hemisphere. The pest damages more than 350 plant species. FAW is genetically divided into two strains viz. corn (C) strain which feeds mostly on maize, sorghum, etc. and the other is a rice (R) strain that prefers rice and other small grasses. In the present study, fall armyworm samples were collected from rice crop in two different places of Tamil Nadu, India during 2019-20 and strain identity was confirmed. Polymerase Chain Reaction (PCR)- Restriction Fragment Length Polymorphism (RFLP) profile of mitochondrial cytochrome oxidase subunit I fragment confirmed the presence of both ‘R’ and ‘C’ strains of FAW in rice crop. Nucleotide variations were observed from PBS, TNAU isolate at five places and two places in Killikulam isolate. Phylogenetic analysis revealed that PBS, TNAU isolate ON247930 (C strain) has completely diverged from Killikulam isolate OM491244 (R strain).

Agave amica (Medik.) (Syn. Polianthes tuberosa L.) is commercially propagated asexually. For the diversification of the crop, seed propagation is essential hence there is a necessity to study the seed germination for hybrid development. A protocol for in vitro germination of tuberose seeds was formulated. Two types of seed were utilized for germination in which the decoated seeds showed early and higher germination percentage than the intact seeds. Seeds inoculated on the basal media composition of half MS with gibberellic acid (1 mg/l) and benzylaminopurine (1 mg/l) recorded minimum time for germination (8 days), higher germination percentage (89.33%) and minimum mean germination time (8.88 days). Seedlings growth were studied under different composition of shoot and root proliferation media. The MS media with naphthaleneacetic acid (2 mg/l) and benzylaminopurine (2 mg/l) increased root length (12.33 cm), shoot length (14.80 cm), number of roots (13.23) and number of leaves (6.25). Under in vivo condition, the seedling developed from the basal media composition of half MS with gibberellic acid (1 mg/l) and benzylaminopurine (1 mg/l) which sub cultured on MS media with naphthaleneacetic acid (2 mg/l) and benzylaminopurine (2 mg/l) showed higher survival percentage of 91.53%.

A study was conducted to understand the stability of seed cotton yield of 105 Bt cotton hybrids (BGI and BGII) using Additive Main effects and Multiplicative Interactions (AMMI) analysis across three diverse locations in India during rainy season 2018. This study holds importance as the hybrids were resistant to Helicoverpa bollworms due to Bt events (MON531 and MON15985) in them which were expected to nullify variation arising out of differential bollworm pressure in different location, unlike in non Bt hybrids where this variation also played role in the stability of the hybrids. The main effect differences among hybrids (41.23 %), environments (39.56 %) and the interaction effects (19.21%) were highly significant of the total variance of seed cotton yield indicating a large difference between the testing location causing different hybrids to perform differently across the testing environments. The first two principal components axes (IPCA I and IPCA II) were highly significant and contributed 52.12 % and 47.88% of total interaction respectively. The distance from the origin and the placement of locations in different quadrants of biplot reflected that the locations were substantially discriminatory as Aurangabad and Dharwad, which were high yielding and Raichur was low yielding. Results showed that hybrids IAHH-8096 BGII, IAHH-8103 BGI, IAHH-8061 BGII and IAHH-8007 BGII were having lowest interaction and stable across the location, whereas hybrids IAHH-8080 BGI, IAHH-8084 BGI, IAHH-8004 BGII and IAHH-8105 BGI were having more interaction and unstable genotypes. Large frequency of hybrids (57) were stable with IPCA scores nearing zero and low ASV values which is attributed resistance to bollworm due to Bt events.

Mutation breeding is the defined approach used for crop production and has played a key role in the creation of several varieties. The present research was carried out to induce mutants in kodo millet variety CO 3 using a physical mutagen (gamma rays) and a chemical mutagen (Ethyl Methane Sulphonate) for creating novelty. Seeds were treated with five doses of gamma-rays viz., 100 Gy, 200 Gy, 300 Gy, 400 Gy, and 500 Gy at BARC, Kalpakam and with three concentrations of EMS viz., 24.15 mM, 32.20 mM and 40.25 mM. In the laboratory test, root and shoot lengths of seedlings were decreased with an increase in the dose of gamma rays and EMS. In field study, the germination percentage and survival rate of seedlings were decreased with an increase in the dose of gamma irradiation and EMS. In M2 generation, five types of chlorophyll mutations viz., albino, xantha, striata, chlorina and albomaculata were observed. Xantha and chlorina were observed in all treatments, whereas, striata and albomaculata were observed only in 200 Gy. Based on the biological damages on M2 plants, mutagenic effectiveness and efficiency were estimated. Both mutagenic effectiveness and efficiency reduced with the increase in the dose of irradiation. Regarding height reduction and lethality, the dose of 100 Gy in gamma treatment and 32.20 mM concentration in EMS treatment recorded maximum efficiency. The mutagenic effectiveness was found to be higher at gamma rays irradiated with 100 Gy and in EMS, in 24.15 mM concentration. The 100 Gray dose and 24.15 mM concentration was found to be highly effective for inducing mutation in kodo millet.

Aim: Drought is one of the most important abiotic stresses that affect the yield of crops globally. The present investigation was conducted to identify small millet genotypes tolerant to seedling stage drought stress. Study Design: The experiment was laid out in Completely Randomized Design (CRD) with three replications with genotypes and stress treatments as factors. Place and Duration of Study: It was carried out at Department of millets, Centre for plant breeding and genetics, Tamil Nadu Agricultural University, Coimbatore, during 2019. Methodology: Ten varieties of various small millets, CO 7 (foxtail millet), CO 4 and ATL 1 (little millet), CO 15 and CO 9 (finger millet), ATL 1 and CO (PV) 5 (proso millet), MDU 1 and CO 2 (barnyard millet) and CO 3 (kodo millet), were used for the study. In vitro screening of the seedlings in Polyethylene Glycol (PEG)-induced water stress at four levels (0, -3, -5 and -7 bars) were carried out based on germination percent, shoot and root length, plant height stress tolerance index (PHSI), root length stress tolerance index (RLSI) and seedling vigour index (SVI). Results: Analysis of variance of the genotypes and PEG treatments revealed significant variation for genotypes, treatments and genotype x treatment interactions at P< 0.001. A declining trend for germination percent, shoot length and root length was observed as the stress levels were increased. However, at mild and moderate stress root length was slightly increased. Under mild (-3 bars) and high stress (-7 bars), CO 7 (foxtail millet) recorded the highest SVI percent over control values (165% and 65% respectively). Under moderate stress CO 4 (little millet) recorded the highest SVI (191%). The lowest SVI values under high stress, 4% and 8%, were recorded for ATL 1 (little millet) and CO 3 (kodo millet) respectively. Conclusion: Based on invitro screening of small millet varieties for seedling stage water stress, foxtail millet variety CO 7 and kodo millet variety CO 3 can be concluded as the tolerant and susceptible varieties respectively. Further a controlled field experiment may be carried out to understand the field level tolerance of the varieties and their growth stages to drought.