Time filter

Source Type

Kleinknecht K.,University of Hohenheim | Mohring J.,University of Hohenheim | Singh K.P.,Directorate of Maize Research | Zaidi P.H.,Indian International Crops Research Institute for the Semi Arid Tropics | And 2 more authors.
Crop Science | Year: 2013

The maize (Zea mays L.) growing area in India is divided into five zones for cultivar testing. During triannual testing of genotypes in official trials within the All-India Coordinated Maize Improvement Program (AICMIP), a large number of entries is rejected each year. Therefore, only a low number of entries is carried forward to the advanced stage of testing. The subdivision of the breeding sites into zones results in limited data per zone. Hence, the question arises how to select the best genotypes per zone and how information can be borrowed across zones to improve the accuracy of selection within zones. We compared the performance of best linear unbiased prediction (BLUP) using the correlation of genetic effects between zones with best linear unbiased estimation (BLUE) based on data per zone. In both cases, data were analyzed using a mixed model. We used simulations to calculate correlations between the true simulated values and the predicted genotype values obtained by BLUE and BLUP using the same models. The data structure and the variance components used in simulations were based on the analysis of 40 triannual series of four different maize maturity groups. Best linear unbiased prediction outperformed BLUE in 38 out of 40 series and on average across all series. An advantage of BLUP was observed for varying genetic correlations between zones. We conclude that the use of BLUP enhanced the estimation accuracy in zoned AICMIP maize testing trials and can be recommended for future use in these trials. © Crop Science Society of America.


Manivannan A.,Directorate of Maize Research | Kaul J.,Directorate of Maize Research | Singode A.,Directorate of Maize Research | Dass S.,Directorate of Maize Research
African Journal of Biotechnology | Year: 2010

Five elite Indian maize inbreds namely; HKI1105, HKI1105, HKI335, CM300 and LM5 were evaluated for callus induction and regeneration. Immature embryos obtained 14 days after pollination were used as explants. Genotype, medium, type of auxin and their concentrations influenced callus induction. N6 medium supplemented with different concentration of 2,4-D (1, 2 and 3 mg/l) and Dicamba (1, 2 and 3 mg/l) were used for callus induction. N6 supplemented with 2 mg/l of 2,4-D has shown highest percentage of embryogenic callus induction. Among the five genotypes tested, CM300 gave highest percentage of embryogenic calli. CM300 and LM5 both have shown higher regeneration percentage of 12.22%. © 2010 Academic Journals.


Gupta H.S.,Vivekananda Parvatiya Krishi Anusandhan Sansthan VPKAS | Gupta H.S.,Indian Agricultural Research Institute | Raman B.,Vivekananda Parvatiya Krishi Anusandhan Sansthan VPKAS | Raman B.,International Maize and Wheat Improvement Center | And 5 more authors.
Plant Breeding | Year: 2013

Vivek Maize Hybrid 9- a popular single-cross hybrid developed by crossing CM 212 and CM 145 was released for commercial cultivation in India. The parental lines, being deficient in lysine and tryptophan, were selected for introgression of opaque-2 allele using CML 180 and CML 170 as donor lines through marker-assisted backcross breeding. The opaque-2 homozygous recessive genotypes with >90% recovery of the recurrent parent genome were selected in BC2F2, and the seeds with <25% opaqueness in BC2F3 were forwarded for seed multiplication. Vivek Quality Protein Maize (QPM) 9, the improved QPM hybrid, showed 41% increase in tryptophan and 30% increase in lysine over the original hybrid. The grain yield of the improved hybrid was on par with the original hybrid. The newly improved QPM maize hybrid released in 2008 will help in reducing the protein malnutrition because its biological value is superior over the normal maize hybrids. This short duration QPM maize hybrid has been adopted in several hill states of North Western and North Eastern Himalayan regions. © 2012 Blackwell Verlag GmbH.


Nepolean T.,Indian Agricultural Research Institute | Singh I.,Directorate of Maize Research | Hossain F.,Indian Agricultural Research Institute | Pandey N.,Indian Agricultural Research Institute | Gupta H.S.,Indian Agricultural Research Institute
Journal of Plant Biochemistry and Biotechnology | Year: 2013

A set of 24 genotypes bred at different centres in India as well as in CIMMYT showing variability for drought tolerance were selected for molecular and morpho-physiological characterization. A set of 35 SSR markers, having genome-wide coverage, was chosen for genotyping the inbreds. These markers generated a total of 111 polymorphic alleles with an average of 3. 17 alleles per locus. The minimum and maximum PIC value was 0. 27 and 0. 77 with a mean of 0. 5. A total of 13 unique alleles were found in the 24 inbred lines. The coefficient of genetic dissimilarity ranged from 0. 192 to 0. 803. NJ-based tree suggested the presence of three major clusters of which, two of them had subgroups. Phenotyping of inbreds by morpho-physiological traits revealed that there was a positive relationship among root length, chlorophyll content, relative water content while anthesis-silking interval was negative relationship with all these traits. Genotyping data complemented by morpho-physiological parameters were used to identify a number of pair-wise combinations for the development of mapping population segregating for drought tolerance and potential heterotic pairs for the development of drought tolerant hybrids. © 2012 Society for Plant Biochemistry and Biotechnology.


Mahajan V.,Directorate of Maize Research | Singh K.P.,Directorate of Maize Research | Ambika Rajendran R.,Directorate of Maize Research | Kanya,Directorate of Maize Research
Indian Journal of Genetics and Plant Breeding | Year: 2012

Maize is a major cereal grown in upland regions of Himalayas especially, Himachal Pradesh, Sikkim, Nagaland and Meghalaya. These states are part of Zone 1 region of All India Co-ordinated Research Project of maize varietal testing of the country. This study aims to assess the change in trend of key traits viz., days to anthesis, days to silk and yield in checks which are used for at least eight years in a row in All India Co-ordinated Research Project of maize in northern hills region. On studying the effect of climate change in rainfall, a shift in peak of rainfall, reduction in peak of total rainfall during the rainiest months and low rainfall in the initial months of the maize crop season was observed. In maize hybrid 'Seed Tech 2324', days to anthesis and silk have decreased by 0.31 and 0.11 days per year, respectively, while in 'Bio 9681' days to anthesis and silk decreased by 0.27 and 0.07 days per year, respectively. Concomitently, there is an increase in yield by 0.29 per cent and 0.10 per cent per year. Over the years, the check genotypes showed change in days to anthesis, days to silk and yield suggesting the importance of crop genetic background in adaption. 'Seed Tech 2324' and 'Bio 9681' are more fit to climate change as compared to 'HIM 129' and 'Surya'. Suitable genotypes like 'Seed Tech 2324' and 'Bio 9681' showed increase in yield in changing favourable conditions in Himalayan region.


Chaudhary D.P.,Directorate of Maize Research | Sapna,Directorate of Maize Research | Mandhania S.,Directorate of Maize Research | Kumar R.,Directorate of Maize Research
Indian Journal of Agricultural Sciences | Year: 2012

The present study was taken up to understand the inter-relationship among various nutritional components of maize (Zea mays L.) kernel. For this purpose, 23 elite maize genotypes received from different centres of All India Coordinated Research Projects on Maize during 2009 and 2010 were used. The samples were ground to powder and processed for the estimation of various nutritional quality parameters such as protein quality, starch, oil and carotenoids and the data was correlated to find the interrelationship between these components. The results showed that the protein content exhibited a significant negative correlation with two important essential amino acids such as tryptophan and lysine. An inverse correlation was found between starch and oil indicating that breeding for high oil maize may lead to lower grain yield. A significant positive correlation was observed between oil content and 100-kernel weight postulating that although increase in oil down-regulate the starch content, the total grain yield, however, would remain unaffected. Protein content showed a non-significant negative correlation with 100-kernel weight. A significant positive correlation was noticed between protein and starch. Another important finding of this study is the positive correlation observed between oil and fat soluble total carotenoids. Breeding for high oil, therefore, would have the added advantage of biofortification of maize. The findings will help to develop improved maize having an answer to better nutrition.


Kumar B.,Directorate of Maize Research | Kumar B.,Indian Agricultural Research Institute | Talukdar A.,Directorate of Maize Research | Talukdar A.,Indian Agricultural Research Institute | And 6 more authors.
Australian Journal of Crop Science | Year: 2014

Yellow mosaic virus (YMV) is a major disease of soybean, which can cause up to 80 % yield loss in severe cases. Chemical or cultural control of YMV is neither economical nor environment-friendly. Deployment of genetic resistance is considered to be the effective way to control it. Therefore, present study was conducted to identify stable sources of resistance for YMV disease, and their molecular characterization. A 500 soybean germplasm lines, collected from different parts of the world were screened for YMV disease reaction at YMV hotspot consecutively for 3 years (2007-09). It could identify 96 genotypes, comprising 48 each of resistant and susceptible genotypes that showed stable disease reactions over the years. Soybean 'R' gene-based primer pair linked with YMV variation in Vigna mungo failed to differentiate the YMV resistant and susceptible soybean genotypes. Genetic diversity panel of the 96 soybean genotypes was analyzed with 121 simple sequence repeat (SSR) markers, of which 97 were polymorphic (80.16% polymorphism). Total of 286 normal and 90 rare alleles were detected, with a mean of 2.36 and 0.74 alleles per locus, respectively. The mean of polymorphism information content (PIC) was 0.32, which ranged from 0.06 to 0.75. UPGMA cluster analysis grouped the genotypes into three major clusters which were further sub-grouped into 6 sub-clusters. Patterns of grouping were supported by the principal component analysis (PCA). The pair-wise genetic similarity values as calculated by Jaccard's coefficients, ranged from 0.39 to 0.95 with an overall mean of 0.65. The findings of the study thus strongly indicated the need for broadening the genetic base of the present Indian soybean cultivars, and also suggested the use of exotic collections that were found resistant to YMV for genetic enhancement of soybean.


Saharawat Y.S.,International Rice Research Institute | Singh B.,CCS Haryana Agricultural University | Malik R.K.,CCS Haryana Agricultural University | Ladha J.K.,International Rice Research Institute | And 3 more authors.
Field Crops Research | Year: 2010

The rice-wheat rotation covering 13.5 million ha in the Indo-Gangetic Plains is vital for food security. Its sustainability is at risk as the current production practices are inadequate resulting in high cost of cultivation and inefficient use of inputs (i.e. water, labor and energy). In a field study, we evaluated resource conserving and cost-saving alternative tillage and crop establishment options with an aim to improve system productivity and efficiency. Treatments included transplanting and direct-seeding of rice after reduced and no-tillage, followed by wheat after no-tillage. Conventional-tilled (puddled) transplanted rice followed by conventional-tilled wheat was included as a current practice. Rice yields of transplanted rice were similar irrespective of tillage/puddling. However, both dry and wet direct-seeded rice yielded 0.45-0.61 Mg ha -1 lower than puddled transplanted rice. Wheat yield after no-tillage was either higher or equivalent to conventional practice. Wheat provided more economic return (US $35 ha -1) than rice. No-till wheat was 6% more profitable than the conventional practice (T1). Rice transplanting with or without puddling had similar water application but dry direct-seeded rice had 10-12% lower and wet direct-seeded rice 20-24% higher. Machine labor without tillage was lower by maximum of 51 and 43% in rice and wheat, respectively. Similarly, human labor was also 9-16% lower in no-till rice compared to other practices. Two years results consistently showed $35 more net income when rice was transplanted without puddling than that of conventional practice. Direct-seeded/un-tilled rice had variable response in 2 years; US $16 more in year 1 and similar in year 2 to the puddled transplanted rice. Direct-seeded or transplanted rice after no-tillage can be more efficient and profitable alternatives to current practice (puddled transplanted rice), however, require further refinement in areas of cultivar development for no-till direct-seeding condition, nutrient, water and weed management to harness maximal potential. © 2010 Elsevier B.V. All rights reserved.


Ganesan S.K.,Indian Agricultural Research Institute | Singh R.,National Bureau of Plant Genetic Resources | Roy Choudhury D.,National Bureau of Plant Genetic Resources | Bharadwaj J.,National Bureau of Plant Genetic Resources | And 2 more authors.
Industrial Crops and Products | Year: 2014

Genetic diversity assessment is prerequisite for future crop improvement programme therefore in the present study, morphological and molecular diversity among the 12 Indian drumstick (Moringa oleifera Lam.) populations were assessed. A total of 300 genotypes belonging to 12 populations of drumstick (M. oleifera Lam.) were collected from northern (Himachal Pradesh) and southern (Tamil Nadu) parts of India. Under field condition 14 qualitative and 11 quantitative morphological characters were recorded to assess the diversity at morphological level. Correlation studies showed significant correlation between the quantitative characters. At molecular level, 19 SSR primers that produced clear and reproducible bands were selected for diversity study. A total of 35 bands were amplified of which 29 (82.86%) were polymorphic with an average of 1.84 bands per primer. Polymorphic information content (PIC) value for SSR primers ranged from 0.01 for primer MO64 to 0.37 for primer MO1 with an average of 0.15. The gene diversity ranged from 0.01 to 0.49 with an average of 0.18. Cluster analysis based on morphological characters (qualitative and quantitative) divided populations into two groups whereas; SSR makers divided it into three groups. Population MO9 (PKM1) form Periyakulum, Tamil Nadu was ungrouped based on quantitative characters. Principal coordinate analysis (PCoA) with SSR markers showed that large diversity existed in Indian drumsticks collection. The percentage of variation explained by the first 3 axes was 31.69% (axis1 - 14.35%, axis2 - 9.39% and axis3 - 7.95%). Analysis of molecular variance (AMOVA) indicated that 2% diversity was attributed to differences among regions, 3% at the level of populations and 95% contributed by the genotypes within the populations. Model based population structure were tested using K values from 1 to 20, but there was no clear population structure, therefore Ln(PD) derived δ. k was plotted against the K to determine the number of populations. Based on population structure analysis five clear populations were obtained instead of 12 natural populations. Cluster analysis and structure based population study showed that, no geographical isolation exists between genotypes collected from northern and southern part of India. Principal coordinate analysis showed large genetic diversity exists in Indian drumstick collection which can be utilised for crop improvement programme particularly traits related to oil yield. © 2014 Elsevier B.V.


PubMed | Monsanto Corporation, National Bureau of Agriculturally Important Insects and Directorate of Maize Research
Type: Journal Article | Journal: Pest management science | Year: 2015

Among the major pests of maize in India are two stem borers, Chilo partellus (Swinhoe) and Sesamia inferens (Walker), and an earworm, Helicoverpa armigera (Hbner). As a pest control strategy, transgenic Bacillus thuringiensis (Bt) maize hybrids are undergoing regulatory trials in India. We have determined the sensitivity of the target lepidopterans to the insecticidal Bt proteins expressed in Bt maize, as this determines product efficacy and the resistance management strategy to be adopted. Maize hybrids with event MON89034 express two insecticidal Bt proteins, Cry1A.105 and Cry2Ab2.Sensitivity profiles of 53 populations of C. partellus, 21 populations of S. inferens and 21 populations of H. armigera, collected between 2008 and 2013 from maize-growing areas in India, to Cry1A.105 and Cry2Ab2 proteins were generated through dose-response assays. Cry1A.105 protein was the most effective to neonates of C. partellus (mean MIC90 range 0.30-1.0g mL(-1) ) and H. armigera (mean MIC90 range 0.71-8.22g mL(-1) ), whereas Cry2Ab2 (mean MIC90 range 0.65-1.70g mL(-1) ) was the most effective to S. inferens.Populations of C. partellus, S. inferens and H. armigera were susceptible to the Bt proteins Cry1A.105 and Cry2Ab2. The Bt sensitivity data will serve as precommercialisation benchmarks for resistance monitoring purposes.

Loading Directorate of Maize Research collaborators
Loading Directorate of Maize Research collaborators