Amit Vikram

Heterosis Studies for Yield and its Components in Tomato (Solanum lycopersicum L.) under North Western Himalayan Region, India

Plant breeders have extensively explored and utilized heterosis to boost yield levels in several cross-pollinated crops in the recent past. However, tomato being a highly selfpollinated species, the scope for exploitation of hybrid vigour depends on the direction and magnitude of heterosis, and ease with which hybrid seeds can be produced. Commercial exploitation of hybrid vigour in tomato has received greater importance on account of several advantages of hybrids over pure line varieties with resistance/tolerance to biotic and abiotic stresses. Hence, identification of high yielding and stable varieties and the development of F1 hybrids will help the farmers to adopt variety/hybrid for successful commercial cultivation of tomato. The reproductive biology and production of appreciable quantity of seeds per fruit provide plentiful opportunity for manifestation of heterosis in tomato (Singh and Singh, 1993). Heterosis in tomato was first observed by Hedrick and Booth (1968) for higher yield and more number of fruits. Since then, International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 7 Number 02 (2018) Journal homepage: http://www.ijcmas.com

Effect of Plasma Treatment on Growth Parameters and Seed Quality of Bell Pepper (Capsicum annuum L.) under Field Conditions

Bell pepper (Capsicum annuum L.) commonly known as sweet pepper, capsicum, green pepper or Shimla mirch, belongs to family Solanaceae. It originated in new world tropics and subtropics (Greenleaf, 1986) and was brought to India by the Portugese from Brazil prior to 1885. It was introduced to Himachal Pradesh by the British in the 19 th century. Bell pepper has attained a status of high value crop in India in recent years and occupies a pride of place among vegetables in Indian cuisine because of its delicacy and pleasant flavour coupled with rich content of ascorbic acid, other vitamins and minerals (Agarwal et al., 2007). Quality of seed is of utmost importance to have good and uniform crop stand. The occurrence of seed hardness and low percentage of seed germination are major challenges in growing capsicum. Low seed germination and rapid deterioration of bell International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 7 Number 09 (2018) Journal homepage: http://www.ijcmas.com

Effect of cold plasma treatment on physiological quality of okra seed

Effect of cold plasma treatment on okra cv P-8 seed germination and seedling vigour were studied. The treatments comprised of two aged seeds, seven seed plasma treatments and four storage durations. Results showed that plasma treatments had positive effects on seed germination and seedling vigour at plasma treatment of 12 min duration on one year old seed stored for 0 months had the highest stimulatory effect. Germination and vigour indices significantly increased by 16.42% and 50.66% respectively. Characteristics of speed of germination, seedling length, seedling dry weight, seedling vigour index-II, significantly increased by 36.18, 30.60, 52.87 and 77.98% respectively, compared with control. It was found that immediately after plasma exposure the germination (91.07%) and vigour (2281.57) were highest and it was reduced to (80.00%) and (1460.74) after 9 months of storage in one year old seed. These results indicated that cold plasma treatment might promote the growth and modify the speed of germination.

Character association and path coefficient analysis for yield and quality traits in tomato (Solanum lycopersicum L.) under mid-hills of Himachal Pradesh

The present investigation was carried out to study the correlation and path coefficient between yield and quality traits at the experimental farm of Dr. Yaswant Singh Parmar University of Horticulture and Forestry, Solan during Kharif season, 2014. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. Positive association of yield components with average fruit weight, plant height, inter-nodal distance, pericarp thickness and harvest duration was observed. Significant direct effect towards yield was contributed by average fruit weight followed by number of fruits per plant, pericarp thickness and harvest duration, whereas number of fruits per cluster, number of locules per fruit, days to first picking, total soluble solids and inter-nodal distance showed negative direct effect. The indirect effect of number of fruits per cluster was of sufficient magnitude via number of fruits per plant. Pericarp thickness and locular wall thickness also exhibited high indirect effect via average fruit weight. Considering the direct and indirect effect of various components characters, it was ascertained that average fruit weight, number of fruits per plant, pericarp thickness and harvest duration are the characters to be emphasized in improving the yield.

Effect of Storage and Umbel Orders on Seed Quality of European Carrot Cultivar Solan Rachna under Cold Desert Conditions of Himachal Pradesh

These investigations were carried out to study the effect of umbel orders and storage on seed quality of European carrot cv. Solan Rachna produced and stored in cold desert conditions at RHRSS, Tabo, Lahaul and Spiti, HP during 2008–2012. Significant differences among seeds of different umbel orders were observed with respect to 1000-seed weight, seedling length and seed vigour index-I. Heaviest seeds were produced on primary umbels with 1000-seed weight of 1.53 g followed by secondary umbel seeds (1.49 g), mixed seed lot (1.42 g) and tertiary umbel seeds (1.19 g). Germination showed a progressive decrease with increasing umbel order. The longest seedlings (10.60 cm) were observed in primary umbel seeds. Similarly, the most vigorous seeds were borne on primary umbels. Storage period affected physiological traits like germination, seedling length and seed vigour. The highest germination (68.67%) was observed in the fresh seeds and lowest (30.33%) in oldest seeds. The longest seedlings were produced by the fresh seed and the length decreased with the storage period of the seed lot. Seed Vigour Index-I decreased with storage period of the seeds. Interaction of umbel order and storage period of carrot seed significantly affected physiological quality. The longest seedlings (11.71 cm) were produced by the youngest seeds of primary umbel, whereas the shortest seedlings were produced by the mixed lot seed stored for three years. Seedling length decreased significantly with increasing storage period within umbel orders. Primary umbel order seeds had least germination reduction with increasing storage period. Vigour deterioration was more pronounced in seeds of inferior umbel orders.

Morphological, Cultural, Pathological and Molecular Variability among Fusarium oxysporum f.sp. zingiberi isolates

Nineteen isolates of Fusarium oxysporum f.sp. zingiberi causal organism of Fusarium yellows in ginger were collected from different ginger growing areas of Himachal Pradesh and designated as I1 to I19. Morphological variations with respect to mycelial colour, conidial size and formation of chlamydospores and pathogenic variation in terms of disease incidence among different isolates was studied in these isolates. The mycelial colour varied from white to dull white with slightly pinkish tinge. The microconidial size varied from 5.20×4.00 μm (I8) to 12.30×5.70 μm (I3) whereas macroconidial size varied from 16.20×4.70 μm (I7) to 32.0×5.70 μm (I4). Chlamydospore dimensions also varied in all the nineteen isolates of the test pathogen. All isolates formed chlamydospores on PDA medium. Pathogenic variability revealed that lesion size varied from 8.50 to 18.00 mm after 10 days of inoculation whereas, incubation period varied from 11 to 19 days. Genetic variation was also analysed by using forty 10 – mer oligonucleotide RAPD primers, out of which 2 primers yielded informative, strong and reproducible DNA amplicons of Fusarium oxysporum f.sp. zingiberi and thus were selected for studying the variation among isolates. The dendrogram of DNA fingerprints revealed 0 to 80% variation among isolates. All isolates were grouped into two different major groups each comprising of ten and nine isolates, respectively.