1,460 research outputs found
Nature of gene action for fruit quality characters of tomato (Solanum lycopersicum)
Nature of gene action for three important fruit quality characters of tomato viz., total soluble solids (TSS), β-carotene and lycopene contents were determined by analyzing one 7 x 7 half diallel population and six genetic populations (P1, P2, F1, F2 , BC1 and BC2) of two cross combinations. The nature of gene action determined from two biometrical methods matched well and it appeared that the fruit quality characters were under the control of both fixable and non-fixable gene effects, with the non-fixable gene effects with gene interactions being more important. Diallel analysis revealed moderate narrow sense heritability estimates and 6-parameter model suggested duplicate epistasis as well as significant additive x additive type non-allelic interaction with negative sign for the characters, which will hinder the pace of progress through simple selection. Single seed descent method with progeny row testing and deferred selection will be the best breeding method to develop line bred varieties with good fruit quality character.Keywords: Gene action, diallel, generation mean, fruit quality, tomatoAfrican Journal of Biotechnology Vol. 12(20), pp. 2869-287
Nueva especie de Trissopelopia Kieffer, 1923 (Diptera, Chironomidae, Tanypodinae, Pentaneurini) de la India
The pupae and adults of Trissopelopia bifurcata sp. n. are recorded and described from the Darjeeling Himalayas of India. The genus is recorded for the first time in India. A new key to the world species of Trissopelopia is also included.Se describen las pupas y los adultos de Trissopelopia bifurcata sp. n. procedentes del Darjeeling Himalayas (India). Es la primera cita del género en la India. Se proporciona, asimismo, una nueva clave mundial de las especies de Trissopelopia
Una nueva especie de ortocladino de Rheocricotopus Thienemann & Harnisch (Diptera, Chironomidae) de Darjeeling–Sikkim, en el Himalaya indio
The adults and pupa of a new species, Rheocricotopus rarispina are described from the Darjeeling–Sikkim Himalayas in India. The species is distinguished by the few spines on the thoracic horn, anal lobe without fringe and bristle–like L setae and presence of ovoid humeral pit, nine squamal setae, structure of anal point and triangular and subterminal crista dorsalis in the adult male. With this new species, the number of Indian species of the genus rises to six.En este trabajo se describen los ejemplares adultos y las crisálidas de una nueva especie, Rheocricotopus rarispina, procedente de Darjeeling–Sikkim, en el Himalaya indio. Dicha especie se identifica por la existencia de algunas espinas en el cuerno torácico, el lóbulo anal sin franja y sin setas parecidas a cerdas en forma de L, la presencia de una cavidad humeral ovoide, nueve setas escamosas, la estructura de la cresta anal y cresta dorsal triangular y subterminal en el macho adulto. Con ésta, el número de especies de origen indio del género asciende ya a seis
ISOLATION OF PROMISING MUTANT OF ENHANCED FRUIT QUALITY IN TOMATO
Induction of mutation by gamma rays, ethyl methane sulfonate (EMS) and their combined treatments was studied in three widely divergent genotypes of tomato, EC-620176, EC-620177 and Patharkutchi. Combination of gamma radiation and EMS caused more damage followed by EMS treatment and gamma radiation, mainly in M1 generation. Gamma irradiation (50-150 Gy) was most efficient followed by 0.05- 0.10 % EMS and their combination treatment in inducing wide array of macro-mutation in tomato. One mutant “Dark green fruit” was isolated from the M2 population of Patharkutchi treated by 150 Gy gamma radiation. Chlorophyll ‘a’, Chlorophyll ‘b’ and total chlorophyll content in the leaf and immature fruit of this mutant was significantly higher compared to the parental genotype. Average total chlorophyll content in the leaf and immature fruit of the mutant over M3 and M4 generation was 318.52 mg/100 g fresh and 21.93 mg/100 g fresh, respectively in sharp contrast to 198.25 mg/100 g and 12.21 mg/100 g fresh, respectively in the leaf and immature fruit of the parental line. This “Dark green fruit” mutant with higher average lycopene (7.49 mg/100 g fresh) and ascorbic acid (35.86 mg/100 g fresh) contents in the ripe fruits emerged as a promising genetic resource for further utilization in tomato breeding for enhancement of lycopene and ascorbic acid content in the fruits
Parameterizing ice nucleation rates using contact angle and activation energy derived from laboratory data
The rate of ice nucleation in clouds is not easily determined and large discrepancies exist between model predictions and actual ice crystal concentration measured in clouds. In an effort to improve the parameterization of ice nucleating in cloud models, we investigate the rate of heterogeneous ice nucleation under specific ambient conditions by knowing the sizes as well as two thermodynamic parameters of the ice nuclei – contact angle and activation energy. Laboratory data of freezing and deposition nucleation modes were analyzed to derive inversely the two thermodynamic parameters for a variety of ice nuclei, including mineral dusts, bacteria, pollens, and soot particles. The analysis considered the Zeldovich factor for the adjustment of ice germ formation, as well as the solute and curvature effects on surface tension; the latter effects have strong influence on the contact angle. Contact angle turns out to be a more important factor than the activation energy in discriminating the nucleation capabilities of various ice nuclei species. By extracting these thermodynamic parameters, laboratory results can be converted into a formulation that follows classical nucleation theory, which then has the flexibility of incorporating factors such as the solute effect and curvature effect that were not considered in the experiments. Due to various uncertainties, contact angle and activation energy derived in this study should be regarded as "apparent" thermodynamics parameters
Water Stress Assessment in Jharkhand State Using Soil Data and GIS
In this paper an attempt has been made to study the interrelationship of water resources available with that of soil class and its properties including soil drainage and erosional characteristics which has been used to generate drainage stress map and water stress map inferring the basic reason for water scarcity in the district of Jharkhand, India. It has been found that 62.71% of soil is classified as well – excessively drained soils whereas only 18.13% of soil is imperfectly- poorly drained. It was also found that only 12.31% and 28.4% of total soil show slight erosion and severe erosion characteristics whereas remaining is moderately eroded. Jharkhand state is facing acute water crisis and due to lowering of ground water table. Thus this work would help the administrators and decision makers in assessing the role of soil in groundwater recharge. It has been concluded that soil is an important factor that controls ground water recharge and water stress of the region. GIS has proved to be an important tool in assessing the area in short span of time. An attempt has been made to highlight that there are various natural parameters that control ground water recharge and soil is one of the controlling parameter in Jharkhand (INDIA)
Self-induced Transparency in a Semiconductor Quantum Dot medium at ultra-cold temperatures
We investigate the feasibility of minimum absorption and minimum broadening
of pulse propagation in an inhomogeneously broadened semiconductor quantum dot
medium. The phonon interaction is inevitable in studying any semiconductor
quantum dot system. We have used the polaron transformation technique to deal
with quantum dot phonon interaction in solving system dynamics. We demonstrate
that a short pulse can propagate inside the medium with minimal absorption and
broadening in pulse shape. The stable pulse area becomes slightly higher than
the prediction of the pulse area theorem and is also dependent on the
environment temperature. The change in the final pulse shape is explained very
well by numerically solving the propagation equation supported by the
susceptibility of the medium. Our system also exhibits the pulse breakup
phenomena for higher input pulse areas. Therefore, the considered scheme can
have important applications in quantum communication, quantum information, and
mode-locking with the advantage of scalability and controllability.Comment: 11 pages, 11 figure
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