Phytotoxicity of Two Bauhinia Species on Four Triticum aestivum Varieties in Laboratory Bioassay

Tree–crop interaction studies help to determine the effects of trees on the production and yield of agricultural crops and could help indecisions on suitable crops and tree combinations to increase the overall production from agroforestry systems. Different varieties of agricultural crops might show different responses against the phytotoxic effects of Bauhinia species. This study was conducted to observe the phytotoxicity of two Bauhinia spp., i.e., Bauhinia retusa and Bauhinia variegata, on some Triticum aestivum varieties, i.e., VL-892, VI-829, VL-616, UP-2572, and UP-1109.The leaves and bark of these two species were harvested from the natural population for these experiments. On average, germination and radicle and plumule length of wheat varieties were significantly (p > 0.05) reduced by the leaf and bark extracts of both Bauhinia species. The effect of leaf and bark extracts of both Bauhinia species on seed germination percent of different wheat varieties revealed that the bark and leaf extracts showed maximum toxicity for germination percentage, and minimum influence was observed in radicle and plumule length. However, bark extracts were more toxic as compared to leaf extracts. Under leaf and bark extract concentrations, the VL 829 wheat variety showed stimulatory effects in germination and radicle and plumule growth under both Bauhinia species. On average, radicle and plumule growth of the test crop was increased with an increasing concentration of leaf and bark extract of B. variegata up to 50%, and thereafter, a decrease in radicle and plumule length was recorded. The VL 829 and UP 1109 varieties showed the lowest allelopathic effects and could be grown under both Bauhinia species with minimum yield loss.