Sumita Sircar , H. C. Sindhu Veerendra

Abstract

A Eucalyptus tereticornis F₂ generation progeny trial was established at Midnapore, West Bengal for recurrent selection for fast growth from 49 families. The parents were selected from seedling seed orchards and seedling seed production areas in Karnataka, Tamil Nadu and Pondicherry. The progenies exhibited a good amount of population variation in the form of CV and ANOVA revealed intra- specific variation in all growth components indicating canalization of growth factors from parents and sufficient diversity within the population which can be exploited for further improvement (total height- p = 0.003 and girth at collar- p = 0.001). General combining ability and breeding values obtained from best linear unprediction were estimated for total height and girth at collar. The growth components showed wide ranges in these parameters suggesting a good interaction between alleles. A recurrent selection was made with ten best parents having highest breeding for synthesizing F₃ generationbreeding population.

Keywords

Seedling Seed Orchard, Variation, Growth Components, General Combining Ability, Recurrent Selection, Genotype, Eucalyptus tereticornis

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H. C. Sindhu Veerendra , H. S. Anantha Padmanabha

Abstract

No abstract

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H. C. Sindhu Veerendra

Abstract

An exploratory survey was undertaken and 10 provenances of neem were collected from Karnataka and Andhra Pradesh during June, 1993. Analysis of three characters i.e., seed length, width and seed weight revealed good amount of genetic variability for those characters studied. Ramanager 'H' provenance represent highest value of Range and lowest of C.V. for all three characters studied. The highest C.V. for seed length was recorded in Ramanager 'Y' provenance (73%), for seed width and seed weight, it was Hosakote provenance (35.7 and 25.1% respectively).

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H. C. Sindhu Veerendra , C. R. Sarma

Abstract

The effect of time of emergence of seedlings on seedling vigour is studied in this paper. It is found that the sooner the emergence, the poorer will be the vigour and the later the emergence of seedlings, the greater will be the vigour of seedlings. Among the seed sources tried, the best one is identified through statistical analysis of the data recorded.

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Sumita Sircar , H. C. Sindhu Veerendra

Abstract

A computerized index scheme was developed for selection of candidate plus trees in Eucalyptus tereticornis provenances and an overall increase in the yield in the volumetric traits was achieved in the selected population. To quantify the realized gains and thereby to test association of variability within each of selected population, several runs were conducted with different number of trees. Realized gains and level of variation exhibited strong associate ships. Selection of large number of trees decreases the gains but overall population variability was increased. As gains increased, level of variation was decreased. However, a trade-off existed between the two. Hence, the genotypes retain tbeir superiority. As an ideal strategy, a run with 66 candidate plus trees were selected which gives sufficient selection pressure allowing sufficient variation to float within the selected population. Total be ight exhibited a selection differential of 6.8 m with a se.lection pressure of 36.82%. Clear bole beight has a selection differential of 3.23 m and selection pressure of22.12%. Similarly, GBH bas selection differential of 27.73 cm and 68.17% selection pressure was exerted foUowed by number of branches with 4.94 and 65.6% selection differential and selection pressure respectively. The yield improvement is associated with lower co-efficient of variation indicating lower amount of population variability which facilitates formation of uniform plantations.

Keywords

Tree Improvement, Variation, Yield, Growth, Index Selection

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Sumita Sircar , Amit Kumar Saha , H. C. Sindhu Veerendra , Ruby S. Kujur

Abstract

Lac is produced by an insect Laccifer lacca (Synonym: Kerria lacca; super family Coccoidea). There are about 160 tree species that serve as host but mainly reared on Zizipus mauritiana, Schleichera oleosa and Butea monosperma in India. Two strains- kusumi and rangeeni are prominently cultivated in India and both differ in their seasonal cycle. The variation observed in bimonthly prices was ascribed to seasonal harvesting rather than prices themselves. Prediction of price movement of mean sticklac was carried out for next five years by regression method on a linearity between export performance and current market dynamics indicates steady prices for sticklac in local markets however, with a slight decrease in prices at later stages (R²= 0.53). Similarly, local market fluctuations on current trend scenario will remain in future also (R²= 0.44). Regression of exported lac products predicted a steady export performance for next five years assuring retention of current domestic price trend. The demand in international markets for lac products will remain steady and may slightly increase due to awareness of consumers to use natural products in place of synthetic products. It is suggested that a support pricing policy may be adopted for lac-support price on annual basis.

Keywords

Local Market Prices, Export of Lac Products, Natural Products

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