Buds : A bud is a compact underdeveloped shoot having a growing point, surrounded by closely placed immature leaves.
Modifications of buds :
1. Bulbils : They are specialised buds, which become flfeshy due to storage of food and take part in vegetative reproduction. Bulbils may be axillary on the leaf, in place of flower on the floral axis.
2. Tendrillar buds : Buds in some plants are modified into long threads, called tendrils. They help the plant in climbing over some support, e.g., Cucurbita,Passiflora.
3. Bud thorns : In some plants, buds are modified into thorns to reduce transpiration and to act as organs of defence against grazing, e.g., Duranta