The genetics of yield and related traits was studied in barley (
L.) by means of 10 × 10 half-diallel progenies (F
) at three sowing dates. An additive-dominance model fitted only for flag leaf area, spike length and 1000-grain weight at different sowing dates. Both additive (D) and dominance components (H
) were significant for all the traits studied, indicating the preponderance of dominance components in controlling the inheritance for these traits. The value of (H
indicated over-dominance for all the traits except for flag leaf area. Values of ‘F’ indicated an excess of dominant alleles in the parents for all traits except for flag leaf area. The environmental component ‘E’ was significant for all traits. The ratio of H
indicated the symmetrical distribution of genes for all the traits studied. The value of h
was less than one for all traits except for spike length, suggesting that a dominant gene was involved in controlling the inheritance of spike length, whereas multiple genes controlled the inheritance of the remaining traits. The heritability estimates were relatively moderate for flag leaf area and 1000-grain weight, but low for all other traits. However, epistatic interactions had an important role in the expression of other traits. Breeding methods such as bi-parental mating in early segregating generations or diallel selective mating may be advantageous to combine important yield component characters for a tangible advance in six-rowed barley.
The experimental material comprised three crosses, namely Cocorit 71 × A-9-30-1, HI 8062 × JNK-4W-128 and Raj 911 × DWL 5002, generated from six diverse parents. Twelve populations of each of these three crosses revealed that sufficient genetic variation was recorded among generations for all the traits in three crosses. The results of a correlation study demonstrated that the grain yield per plant was significantly and positively associated with peduncle area and flag leaf area in the cross Cocorit 71 × A-9-30-1. However, the spike area had poor correlation with grain yield. In the cross HI 8062 × JNK-4W-128, grain yield per plant was positively associated with peduncle area and spike area, whereas flag leaf area showed a positive but weak association with grain yield. In the cross Raj 911 × DWL 5002, grain yield per plant was positively associated with all three physiological traits studied, indicating that improvement in grain yield may be made by these traits in this material. Peduncle area appeared to be the most important trait in the present study because of its association with grain yield in all three crosses. Although flag leaf area and spike area showed a positive association with grain yield in all three crosses, their relative magnitudes and significance changed from one cross to the other. Correlation studies revealed that selection for peduncle area would lead to high yield in durum wheat. However, due consideration should also be given to flag leaf area and spike area during the selection of plants for further tangible advances in grain yield in durum owing to their positive association with grain yield.
The results obtained for the parental, F
generations of a 10 × 10 diallel set (excluding reciprocals) of durum wheat revealed that there were significant differences between all the hundred genotypes for all the characters. The genotypes represented a wide range of expression for almost all the characters. High estimates of GCV (genetic coefficient of variation) were observed for the number of effective tillers, grain yield per plant, harvest index and 1000-grain weight. The low values of GCV recorded for days to heading, grain protein content and plant height indicated their limited scope for improvement. High heritability (h
) values ranging from 92.27% (grain yield/plant) to 99.00% (protein content) were observed for all the characters. The highest expected GA (genetic advance) as a percentage of the mean was manifested for harvest index, followed by plant height, number of effective tillers per plant and grain yield per plant. These traits also possessed high estimates of heritability, indicating that most of the variation in these characters was due to additive gene effects. For protein content high heritability was observed with low genetic gain, indicating non-additive gene effects. Thus, a systematic approach based on selection for harvest index, plant height and number of effective tillers per plant on the basis of high
performance would be the most effective approach for improving the yield level of durum wheat. The wealth of variability available in the hybrid populations offers good prospects for its improvement in the near future.
Authors:P. Singh, Y. Sharma, R. Sharma, and G. Singh
In the present study on the self-incompatibility in inbred lines of ten local Indian cultivars (Pusa Chetki, Chetki Long, Aushi, Alipur Local White, Jaunpuri, Half Red, Scarlet Red, Chinese Pink, Desi Red and Khasi Kata) of radish (
L.), Pusa Chetki, Chetki Long, Aushi, Alipur Local White and Jaunpuri were classed as selfcompatible, Half Red, Scarlet Red and Chinese Pink as intermediate and Desi Red and Khasi Kata as self-incompatible. The highest number of germinated pollen grains and pollen tubes was observed in Pusa Chetki, followed by Alipur Local White, Jaunpuri, Aushi and Chetki Long. The discrepancy in the number of germinated pollen grains in the stigmas may be explained by the inhibitory action of large numbers of self-incompatible pollen grains on the stigma. When two lines, Desi Red and Khasi Kata, were grown under different temperature and photoperiod conditions, no breakdown in self-incompatibility was observed, and the flowering periods of these lines are naturally well synchronized. It is well known that uniform and effective cross-pollination may be of great importance for obtaining a high quantity of hybrid seed in self-incompatible types. To produce single cross hybrid seed, the inbred lines Desi Red and Khasi Kata can be used as parental lines.
Authors:Y. Sharma, S. N. Sharma, P. Joshi, and R. S. Sain
The F1 and F2 progenies of a ten-parent diallel cross (excluding reciprocals) were analysed for the combining ability of quantitative traits in six-rowed barley (Hordeum vulgare L.). significant differences were indicated between the parents, F1s and F2s for all the characters studied. The gca and sca components of variance were significant for all the traits. Both additive and non-additive gene effects were involved in the genetic control of the characters; however, non-additive gene effects were observed to be predominant. Among the parents RD 2035, RD 2052, RD 2503 and BL 2 were the best general combiners for grain yield and average to high combiners for other important traits.The parents RD 2552 and RD 387 were the best general combiners for dwarfness. The best specific crosses for grain yield were RD 2503 × RD 2585,RD 2035 × RD 2052, RD 2035 × BL 2, RD 2052 × BL 2, RD 2508 × RD 2552, RD 2552 × RD 2585 and Rd 2052 × RD 2552 in both the F1 and F2 generations. These crosses were higher yielders and in most of the crosses one of the parents involved was a good combiner, indicating that such combinations can be expected to produce desirable transgressive segregants. All the best crosses for grain yield also showed average to high sca effects for most of the yield components. Most of the specific crosses for grain yield involved high × average, average × average and average × poor general combiners. To ensure a further increase in grain yield, the combination of desirable yield components is advocated. The inclusion of F1 hybrids showing high sca, and having parents with good gca, in multiple crosses, bi-parental mating or diallel selective mating could prove a worthwhile approach for further amelioration of grain yield in six-rowed barley.
Authors:A. Tiwari, Y. Bharti, S. Tripathi, N. Mishra, M. Lal, G. Rao, P. Sharma, and M. Sharma
Research on sugarcane biotechnology began in the 1960s with
culture. Serious efforts to improve sugarcane crops by molecular approaches have commenced only in the past two decades. There is an increasing pressure worldwide to enhance the productivity of sugarcane in order to sustain profitable sugar industries, while there are several diseases attacking sugarcane and reducing the quality of the crop. Biotechnological approaches for sugarcane improvement have been applied in the areas of: (1) cell and tissue culture for rapid propagation genetic transformation and molecular breeding, (2) engineering novel genes into commercial cultivars, (3) molecular diagnostics of sugarcane pathogens, (4) developing genetic maps using molecular marker technology, (5) understanding the molecular basis of sucrose accumulation in the stem, (6) molecular testing of plants for clonal fidelity, (7) variety identification and (8) molecular characterization of various traits. Most of the current research in sugarcane biotechnology is recently focused primarily on transgenic and marker assisted breeding. Advancements have made it possible to sequence the complete genome of increasingly complex organisms and to clone and transfer individual genes to engineer new traits.
Authors:Y. Gautam, S. Sharma, A. Sharma, V. Kumar, J. Kumar, A. Kumar, A. Hegde, and P. Sarkar
Guidelines for the assessment of internal doses from monitoring suggest default measurement of uncertainties (i.e. lognormal
scattering factor, SF) to be used for different types of monitoring data. In this paper, SF values have been evaluated for
internal contamination due to 60Co in two cases using whole body counting data. SF values of 1.04 and 1.03 were obtained for case I and II, respectively while
SF value of 1.03 was obtained using bioassay data for case I. SF evaluated is in good agreement with the default values given
by IDEAS guidelines. The present study also presents the follow up study of a case I of 60Co internal contamination using whole body counting and bioassay analysis. The effect of medical intervention applied on the
subject is studied. Medical intervention of d-Penicillamine (250 mg × 4 daily) was orally administered from 13th day of initial exposure for about a fortnight, which showed
reduction of activity present by 33.4% through urine.
Authors:A. Kumar, Y. Gautam, V. Kumar, K. Rao, S. Sharma, A. Sharma, and A. Hegde
Knowledge of the dynamics of HTO in leafy plant–soil system is required to verify models, such as the NORMTRI code, which
predict environmental tritium following its release. Tritium concentrations in plants has been evaluated using the code NORMTRI
and experimentally by collection of samples of different plants and their soils samples. In the present study, major seasonal
crop plants i.e. wheat, mustard, sugar cane, coriander, spinach, potato, were collected beyond Narora Atomic Power Station
site boundary and gular, arandi, neem, ashok, amaltas, csuarina leaf samples within NAPS site boundary for analysis of HTO
content. Data analysis indicated that HTO in leaf is strongly influenced by atmospheric relative humidity and type of the
Authors:H. Kaur, N. Sarao, Y. Vikal, K. Singh, and R. Sharma
Maize cultivars (4 composites, 14 inbreds and 7 hybrids) cultivated in Punjab were characterized using a set of 70 Simple Sequence Repeat (SSR) markers with a total of 199 alleles. Out of these, 67 markers produced polymorphic profiles, 3 were monomorphic. Eight SSR primers detected eight unique alleles in three genotypes. These unique SSR alleles provide an opportunity for unambiguous differentiation of the respective genotypes. SSR profiles were analyzed by using computer softwares NTSYS-pc and DARwin 5.0. Both of them classified the genotypes in four distinct groups.
Authors:Y. Gautam, A. Sharma, S. Sharma, K. Rao, J. Kumar, V. Kumar, B. Singh, A. Kumar, and A. Hedge
Atmospheric tritium activity is measured regularly around Narora Atomic Power Station (NAPS) since gaseous waste, which contains
tritium, is being released through a 145 m high stack at NAPS site. Atmospheric data collected during 2004–2008 shows a large
variation of 3H concentration in air, fluctuating in the range of ≤0.2–91.6 Bq m−3. Significantly, higher tritium levels were measured in samples near the site boundary (1.6 km) of NAPS compared to off-site
locations. The atmospheric dilution factor was found to be in the range of 1.1 × 10−7–7.3 × 10−7 s m−3. The scavenging ratio of NAPS site was found to be varying from 0.2 × 104 to 14.1 × 104 (Bq m−3 rain water per Bq m−3 air). The inhalation dose to a member of general public at different distances (1.6–30 km) from NAPS site was found to be
ranged from 0.08–0.21 μSv year−1.