Dalbergia sissoo Roxb.(family Fabaceae) is a multipurpose tree with uses as timber, fuel wood, fodder and shade provides, besides being an excellent nitrogen fixer. The present investigation was conducted in a D. sissoo wheat agri-silviculture system to find out correlation of wheat yield and tree biomass with various growth characters of wheat plants and D. sissoo trees, respectively. The wheat crop was sown in the interspaces of a 20 year old D. sissoo plantation, planted at a spacing of 5m×5m. For multivariate analysis, path coefficient approach was adopted using multiple regression and path analysis. Wheat yield was found to be very highly and positively correlated with crop-shoot biomass with coefficient of determination (R2) as 0.93, followed by number of tillers/m row length, 1000-grain weight and plant height with values of R2 as 0.85 and 0.84. Although plant height and length of ear head were also positively correlated with wheat yield but the correlation was not found significant. The best fit linear regeneration equations showed that unit increase in length of ear head, plant height, 1000-grain weight, number of tillers/m row length and crop-shoot biomass (kg/ha) resulted in an increase of 19.67 cm, 3.63 cm, 2.76 g, 1.01/m and 0.01 q/ hectare of wheat yield respectively. Similarly, tree biomass was found to have positive correlation with various tree growth characteristics, viz. stem volume, diameter at breast height (dbh) and tree height. Highly significant correlation was found with the stem volume (R2=1.00), followed by dbh (R2=0.95).

Agri-silviculture, Dalbergia sissoo, wheat, correlation, regression, multivariate analysis.