10.22376/ijpbs.2019.10.1.p1-12 Volume 2 Issue 2 2011 (April - June) Orange yellow coloured flowers of lessThan i greaterThan Tribulus terrestris lessThan /i greaterThan L. have been studied for its pollination biology at Agra region. Mode of pollination indicated that lessThan i greaterThan T. terrestris lessThan /i greaterThan was both self and cross pollinated as there was fruit-set in bagged inflorescence. The potential of the self-pollination was found to be 100% seed-set. Cross-pollination was achieved by both geitonogamy and xenogamy. The fruit formation was not merely dependent on the formation of viable gametes, but also on primary attractants (pollen and nectar) and secondary attractants (orange – yellow colour, odour, small size and fully open architecture and high floral density) that influenced visitors and brought out reproductive success. Honey bees lessThan i greaterThan Apis lessThan /i greaterThan lessThan i greaterThan spp lessThan /i greaterThan . and butterflies lessThan i greaterThan pieris lessThan /i greaterThan and lessThan i greaterThan limenitis sps lessThan /i greaterThan . were found to be the most efficient pollinators during the entire flowering period. Showkat Ahmed Ganaie Tribulus terrestris, pollination biology, floral architecture, fruit-set, seed-set and cross pollination. 316-320