Name the natural cytokinin obtained from maize kernels.

Explanation

**Step-by-Step Solution:**

1. **Understanding Cytokinins**: Cytokinins are a class of plant hormones that promote cell division and growth in plants. They play a crucial role in various plant growth processes, including the development of buds.

2. **Historical Context**: The first natural cytokinin was discovered in 1964. This discovery was significant in the field of plant biology and helped in understanding plant growth regulation.

3. **Source of Cytokinin**: The natural cytokinin was obtained from unripe maize kernels. This indicates that certain plant tissues are rich in specific hormones that can influence growth.

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