<div>Background: An understanding the mungbean mutant lines with the check varieties can help in identifying mutants in better adoption. The present experiment was conducted to assess the genetic variation and morpho-metric characteristics of mungbean mutants in M4 and M5 generation.&nbsp; 
 
Methods: A set of 7 M3 progenies along with parent Pratap and 5 check was evaluated for M4 and M5 generation using randomized complete block design with three replications during kharif 2018 and summer 2019 in the experimental area of Instructional cum Research Farm, College of Agriculture, Assam Agricultural University, Jorhat, Assam. 
 
Result: Significant differences were observed for most of the traits in both M4 and M5 generation. High heritability estimate coupled with high genetic advance as per cent of mean was documented for numbers of branches per plant, pods per plant, percentage of disease incidence, 100 seeds weight and seed yield per plant in both the generation indicate the pre-ponderance of additive gene action. Seed yield per plant was found to be significantly and positively correlated with numbers of pods per cluster, seeds per pod, pod length and 100 seeds weight at genotypic and phenotypic level in both M4 and M5 generation. The traits 100 seeds weight and branches per plant had showed positive direct effect on seed yield in both the generations; hence these two traits might be most effective for selection of higher yield mutants in mung bean.</div>

Characterization of Mungbean Mutants [Vigna radiata (L.) Wilczek] in M4 and M5 Generations

<div>Background: Induction of mutation plays an important role in the breeding programme among modern methods of plant breeding. Genetic variability is prerequisite for crop improvement and through induced mutation it was found to be very effective for creating variability in the quantitative and qualitative characters. Hence, the present study was aimed to induce genetic variability within short time. In the present investigation positive as well as negative impact on quantitative traits were recorded. 
 
Methods: The experiment material comprised of seeds of horsegram [Macrotyloma uniflorum (Lam.) Verdc] variety Paiyur 2 which was subjected to ethyl methane sulphonate (02, 0.3, 0.4 and 0.5%), gamma radiation (100, 200, 300 and 400 Gy) and combination treatments. The mutations affecting gross morphological changes in growth and yield characters such as plant habit, flowering, pod morphology, maturity and seed yield were scored as quantitative characters. The micro mutations at population level can be easily detected in the form of increased variations for quantitative traits in the segregation of mutagen treated populations. Micro mutations can alter morpho-physiological characters hence they are of a particular interest to the plant breeders. ANOVA test was performed to determine the significant differences and duncan&rsquo;s multiple range test (p=0.05) to compare the differences among treatment means.&nbsp; 
 
Result: Among the twenty-five treatments studied both the mutagens, gamma radiations and Ethyl Methane Sulphonate proved to be very effective to induce variability in quantitative traits in M2 and M3 generations. The results of Duncan&rsquo;s multiple range test analysis revealed that the treatment of mutagens in combinations induced more positive effects as compared to that of using alone. The combined treatments were found positive for improvement of primary branches per plant, no. of pods per plant, pod length, no. of seeds/pod and seed yield per plant in M2 and M3 generations whereas the treatment of gamma irradiation imparted its significant role for improvement of plant height, days required for 50% flowering, days to maturity and 1000 seed weight in both M2 and M3 generations whereas the treatment with Ethyl Methane Sulphonate is useful for improving no. of pods per plant and no. of seeds/pod in M2 generation alone.</div>

Studies on Effect of Mutagens on Quantitative Characters in M2 and M3 Generation of Horsegram [Macrotyloma uniflorum (Lam.) Verdc]

Background: The pulse known as &ldquo;Blackgram&rdquo; is a significant component of the Indian diet since it provides vegetable protein and balances the diet centered on cereals. Mungbean Yellow Mosaic Virus (MYMV) outbreaks on a regular basis completely destroy crops, causing farmers to suffer enormous losses. Mutation breeding can be an effective strategy for developing crops with desirable traits, such as high yield and resistance to diseases like the Mungbean Yellow Mosaic Virus (MYMV) in blackgram. 
&nbsp; 
Methods: This experiment was laid out to study the variability pattern of mutant population in M4&nbsp;and M5&nbsp;generation of blackgram variety CO 6 treated with the Gamma rays at 200 Gy, 300 Gy and 400Gy and isolation of viable mutants for Mungbean Yellow Mosaic virus resistance. Significant variability was observed among the different treatments in M4 generation and twenty MYMV resistant mutants ((PKT-BG-200Gy-P07; PKT-BG-200Gy-P24; PKT-BG-200Gy-P29; PKT-BG-200Gy-P35; PKT-BG-200Gy-P36; PKT-BG-200Gy-P45; PKT-BG-300Gy-P13; PKT-BG-300Gy-P16; PKT-BG-300Gy-P28;&nbsp; PKT-BG-300Gy-P33; PKT-BG-300Gy-P41; PKT-BG-300Gy-P4; PKT-BG-300Gy-P43; PKT-BG-300Gy-P76; PKT-BG-300Gy-P81; PKT-BG-300Gy-P88; PKT-BG-300Gy-P93; PKT-BG-400Gy-P15; PKT-BG-400Gy-P21; PKT-BG-400Gy-P23)&nbsp; were selected and evaluated in a randomized block design with three replications under natural conditions.&nbsp; Scoring was done by the modified scale of All India Coordinated Research Project on MuLLaRP. 
&nbsp; 
Result: Incidence ranged from scale 0.01 (PKT-BG-300Gy-P41and PKT-BG-300Gy-P42) to 5.30 (PKT-BG-300Gy-P28). The mutants PKT-BG-300Gy-P41 and PKT-BG-300Gy-P42 recorded with maximum yield of 1500 kg/ha and 1445kg/ha were found to be observed as high yielding and MYMV resistant lines for summer season&nbsp; in the Cauvery delta region.

Evaluation and Isolation of Mungbean Yellow Mosai Virus Resistant Mutants in M4 and M5 Mutant Generations of Blackgram (Vigna mungo)

<div>Background: In agricultural, the field experimenters have been bona fide way of verifying the test result when researchers have developed new cultivating method in order to improve the overall crop production. To meet this requirement experimenters have continuously be measured in thinking the new and/or modified techniques and methodologies.&nbsp; 
 
Methods: To estimate stability variance with two treatments through Graceo-latin square layout apart from prevailing Latin square layout with one treatment. The maximal data information prior and asymptotically locally invariant prior are also studied for the obtained stability variance in such layout. 
 
Result: The Graceo-latin square design layout with two different treatments has been proposed to study genotype &times; environment (G &times; E)&nbsp; interaction. Statistical model for the design and ANOVA is also developed and simultaneous methods are proposed to diagrammatize the respective stability variance.</div>

Stability Variance and its Bayesian Estimation for Genotype &times; Environment Interaction in m &times; m Gracro-latin Square Layout

Background: Butter beans (Phaselous lunatus L) belong to the family Leguminaceae, is one of the oldest cool season food legume crops. A throughout knowledge of existing genetic variation among yield and its yield component traits is essential for developing high yielding varieties in butter bean. Realizing the importance of genetic diversity and variability in key economic characters, the present investigation had been planned to assess the genetic diversity and variability in for yield improvement in butter bean breeding programme. 
 
Methods: Investigation was carried at Horticultural Research Station, Tamil Nadu Agricultural University, Kodaikanal, Tamil Nadu during 2019-2021. A total of 2734 M2 mutant lines were evaluated as individual progenies in the previous study. Stringent selection was made based on yield, earliness and plant habit and a total of 35 mutant lines were identified and forwarded to M3 and a total of 12 mutant lines for M4 generations in present study. The data on elevan quantitative were analyzed using Mahalanobis D2 statistic. 
 
Result: The present study has assessed the genetic variation among studied traits of butter bean mutants for yield and its component traits. Thus, a total of five mutant lines namely BBMG-7-9-7, BBMG-9-10-6, BBMG-18-9-6, BBMG-25-13-3, BBMG-35-7-2 were identified to be forward to the M5 generation as promising mutant lines for developing high yielding varieties and to test its homogeneity and stability.

Genetic Variability and Diversity for Yield and Yield Attributing Traits in M3 and M4 Generations of Butter Bean (Phaseolus lunatus L.)

Background: The objective of the study was to examine the growth and development of M. pancalus larvae in captive conditions, including pigmentation patterns, yolk and oil globule utilization, growth rates and metamorphosis, as well as to identify suitable live food for larviculture. 
 
Methods: The larvae, produced through induced breeding, were kept unfed until the yolk-sac absorption and then fed with freshwater rotifer, mixed zooplankton and Tubifex worms at different stages of development. The larvae were reared in indoor glass tanks and outdoor reinforced plastic tanks to document their morphological and chronological development. 
 
Result: The findings showed that the larvae exhibited typical characteristics of eel. Notably, dentition was observed before yolk resorption, indicating the highly predatory nature of the larvae. The bands of melanophores, which were prominent at the beginning, disappeared between 5-7 days post-hatch. Additionally, the study identified distinct features of spiny eels, such as a trunk-like rostral projection at 14 days post-hatch and erectile dorsal spines at 21 days post-hatch. The growth pattern, morphological changes and adaptation to benthic burrowing habits indicated that the larvae metamorphosed into the fry stage between 28-45 days post-hatch. These results provide valuable insights into the ontogenetic development and rearing of M. pancalus and can be used to support future aquaculture and conservation programs.

Ontogeny and Growth of Early Life Stages of Barred Spiny Eel Macrognathus pancalus (Hamilton, 1822)

<div>Background: The present germplasm of cluster bean lack the needed natural variability for developing early maturing short statured lines. Therefore, an attempt was made to study the magnitude of heritable variability stimulated through induced mutation in M3 generation. 
 
Methods: M3 generation seeds of cluster bean variety MDU1 treated with gamma rays, electron beam and combination of gamma ray with EMS were used in the present investigation. The biometric observations were recorded on ten selected M3 plants from each family of every treatments for six traits viz., plant height, days to first flowering, number of clusters per plant, number of pods per plant, pod length and pod yield per plant. The same method was followed for recording observations on untreated parental materials also. 
 
Result: Studies on the variability parameters indicated that the phenotypic variance, genotypic variance, heritability and genetic advance were higher in combination treatment for all the traits. The shortest mutant and the earliest flowering (3M11) was observed in combination of 100 Gy of gamma ray+20 mM EMS. Mutant for the highest number of clusters (3M3) was observed in combination treatment of 300 Gy gamma ray with 20 mM EMS. The mutants for the highest number of pods per plant (3M1 and 3M2) and the highest pod yield (3M1) were identified at 400 Gy of gamma ray treatment. Fifteen desirable mutants were selected and forwarded to next generation for testing the stability in different environments.</div>

​Genetic Variability Studies in Short Statured Early Maturing M3 Generation Cluster Bean [Cyamopsis tetragonoloba (L.) Taub.] Mutants

Background: MDU-1 is a high yielding, indeterminate cluster bean variety. In order to develop determinate mutant with high yield, MDU-1 cluster bean variety was irradiated using gamma rays, electron beam and combination of gamma rays and EMS with different doses and the variability induced in M5 generations were studied.&nbsp; 
 
Methods: Twenty one best individual plants from M4 generation were selected based on plant height and higher yield and forwarded to M5 generation where they were evaluated in RBD with three replications. Fourteen non-segregating mutant lines with desirable traits were identified in M5 generation and were evaluated for variability along with the parent MDU1.&nbsp; 
 
Result: Five best mutant lines namely ACMC-020-04, ACMC-020-11, ACMC-020-08, ACMC-020-10 and ACMC-020-11 were selected from the 14 accessions based on per se performance and variability analysis. The selected mutants needs to be forwarded for stability testing in different environments.

Genetic Variability Studies in M5 Generations of Determinate Early Maturing Cluster Bean [Cyamopsis tetragonoloba (L.) Taub] (MDU-1) Mutants for Yield and Yield Attributing Characters

<div>Background: We investigated the occurrence of blaCTX-M carrying extended spectrum beta lactamase (ESBL) producing Escherichia coli in pigs from 8 North-eastern states of India with special emphasis on the transferability of ESBL gene from resistant E. coli strains to the susceptible Salmonella strains by in vitro and in vivo. 
 
Methods: Fecal samples (n=790) were collected from pigs reared under organized and unorganized farming set up of entire North-eastern region of India. All the samples were processed for isolation and identification of E. coli. All the isolates were subjected to antimicrobial sensitivity assay by disc diffusion method followed by determination of ESBLs producing ability by double disc synergy test (DDST). All the ESBLs producing isolates were screened for blaCTX-M gene by PCR using specific primers. The representative blaCTX-M gene positive isolates were used as donor to determine the ability to transfer of resistance gene in Salmonella by in vitro and in vivo assays with and without antibiotic selection pressure. &nbsp; 
 
Result: A total of 2,291 E. coli was isolated, of which 1113 and 1178 were from organized and unorganized farms, respectively. Majority of the isolates were multi-drug resistant with highest resistance against amoxicillin (84.81%) followed by cefalexin (77.17%), sulphafurazole (56.79%), piperacillin (46.40%), tetracycline (38.29%) and cefexime (35.66%). Isolates from unorganized farms showed higher resistance than the isolates recovered from organized farms. A total of 654 (28.55%) isolates were confirmed as ESBL producers by double disc synergy test (DDST) method, of which 65 (2.84%) isolates were positive for blaCTX-M gene. Genotypically, isolates with specific amino acids substitution revealed variation in their antibiotic susceptibility by phenotypic method. blaCTX-M gene could be successfully transferred horizontally from E. coli (donor) to Salmonella (recipient) by in vitro (3.6&plusmn;2.07x10-8 to 4.4&plusmn;2.88x10-8 transconjugate per donor) and in vivo method. By in vivo method in pig model, the frequency of transfer was higher under the antibiotic selection pressure (6.6&plusmn;3.05x10-5 to 7.2&plusmn;1.92x10-5 trans-conjugants per donor) than without antibiotic pressure (5.6&plusmn;2.3x10-4 to 6.8&plusmn;3.35x10-4 trans-conjugants per donor).</div>

Transferable blaCTX-M Carrying Multidrug Resistant Escherichia coli from Pig Population of North Eastern Region of India

<div>Background: Macrognathus pancalus or barred spiny eel is a highly valued ornamental and food fish found in the Indian subcontinent. Due to the burgeoning population and their associated impacts, the population of the species is in rapid decline that necessitates time-bound intervention to conserve the species. The current investigation was undertaken to study the gonadosomatic index and gonad histology of Macrognathus pancalus collected from upper Assam, India. 
 
Methods: 500 samples of Macrognathus pancalus were collected from different water bodies such as wetlands, ponds, paddy fields, etc. from upper Assam, India during 2018-2019. Monthly samplings were carried out to evaluate the gonadosomatic index. The gonads were dissected out, measured and subsequently preserved for histological studies. Histological sections of preserved samples were prepared by employing accepted methodologies. The sections were then photographed using Leica DM 750 and gonadal staging was ascertained.&nbsp; 
 
Result: Gonadosomatic index studies revealed that it peaked in August in both males (3.45&plusmn;0.18) and females (8.85&plusmn;0.35), thereby indicating its spawning season. Minimum GSI values were observed during January in males (0.39&plusmn;0.04) and in December in females (1.04&plusmn;0.15) indicating the culmination of the breeding period and the advent of the preparatory phase. Macroscopic and microscopic examination unearthed five different phases of gonadal maturation. Gonadal staging through microscopic and macroscopic technique showed synchronicity with GSI values.&nbsp;</div>

<div>Investigations on Gonadosomatic Index and Gonad Histology of Barred Spiny eel Macrognathus pancalus Hamilton, 1822 from Upper Assam, India</div>

Characterization of Mungbean Mutants [Vigna radiata (L.) Wilczek] in M₄ and M₅Generations

Studies on Effect of Mutagens on Quantitative Characters in M₂ and M₃ Generation of Horsegram [Macrotyloma uniflorum (Lam.) Verdc]

Evaluation and Isolation of Mungbean Yellow Mosai Virus Resistant Mutants in M₄and M₅ Mutant Generations of Blackgram (Vigna mungo)

Stability Variance and its Bayesian Estimation for Genotype × Environment Interaction in m × m Gracro-latin Square Layout

Genetic Variability and Diversity for Yield and Yield Attributing Traits in M₃ and M₄ Generations of Butter Bean (Phaseolus lunatus L.)

Ontogeny and Growth of Early Life Stages of Barred Spiny Eel Macrognathus pancalus (Hamilton, 1822)

Genetic Variability Studies in Short Statured Early Maturing M₃ Generation Cluster Bean [Cyamopsis tetragonoloba (L.) Taub.] Mutants

Genetic Variability Studies in M₅ Generations of Determinate Early Maturing Cluster Bean [Cyamopsis tetragonoloba (L.) Taub] (MDU-1) Mutants for Yield and Yield Attributing Characters

Transferable bla_CTX-M Carrying Multidrug Resistant Escherichia coli from Pig Population of North Eastern Region of India

Investigations on Gonadosomatic Index and Gonad Histology of Barred Spiny eel Macrognathus pancalus Hamilton, 1822 from Upper Assam, India