A modified Murashige and Skoog media for efficient multipleshoot induction in G. arborea Roxb.

This paper reports on the effect of various micropropagation factors of Gmelina arborea Roxb. through multiple shoot induction. Factors like the source and age of explants, plant growth regulators （PGRs）, media composition, and carbon source affected multiple shoot-ing in the present study. Among all the explants used, only shoot tips derived from one, two, and three week old seedlings could form multiple shoots. Besides, the formation of multiple shoots depended on the con-centration and combination of PGRs. Among all the PGRs, BAP （6-benzylaminopurine） alone gave the highest regeneration efficiency. Simi-larly, IBA （Indole-3-butyric acid） was the most efficient PGR in inducing root formation in the microshoots. Media composition and carbon source also affected the regeneration efficiency. MS （Murashige and Skoog medium） proved to be the best media for regeneration followed by B5, SH （Schenk and Hilderbrandt medium） and WPM （Woody plant medium） in that order. Similarly, among sugars, only sucrose and glucose sup-ported induction of microshoots. Based on this study we recommend the use of glucose in place of sucrose in MS medium for maximum regenera-tion efficiency.

Linear programming approach for optimal forest plantation

The aim of this research was to identify species suitable for plantation. We first identified species for potentially suitable for plantation based on ecological capabilities regarding soil properties. We determined the area of plantation for different species based on ecological capabilities. Then, we collected relevant data such as growth patterns of different species, labor requirements for plantation and plantation cost. A linear programming model and two integer linear programming models were used for optimization. The appropriate species based on ecological capabilities were ash, elm, maple, oak and bald cypress. A linear programming model was used based on ecological capabilities classification to determine the land area of different species for plantation. Then, two integer linear programming models were employed to select the species for plantation. We set ecological properties unequal for all of the species in the first run of the integer programming model. Two groups were classified： group one included maple and ash; group two included bald cypress,oak and elm. The second integer programming model assumed equal ecological properties for all the species.Results of linear programming showed that maple and bald cypress were appropriate for plantation at the site and their plantation areas should be 151.3 and 355.3 ha, respectively. Results of the first integer linear programming model showed that maple and bald cypress would be economically profitable for plantation. The results of the second integer linear programming model showed that only bald cypress would be appropriate for plantation.