Ljung, Karin, Rishikesh P. Bhalerao, and Göran Sandberg. 2001. Sites and homeostatic control of auxin biosynthesis in Arabidopsis during vegetative growth. The Plant Journal 28:465-474.
This article focuses on auxin levels and how they affect plant growth and development. It was observed that auxin levels must be regulated and maintained in order to permit continued growth. The study suggests that IAA (auxin) is synthesized at specific sources via a feedback-inhibition mechanism. Through observation, it was found that leaf size and IAA levels were inversely related. In young Arabidopsis seeds, IAA levels start high and drop off post leaf expansion, which means that younger leaves have a higher capacity to synthesize IAA and higher levels of IAA correlate with higher rates of cell division.
http://onlinelibrary.wiley.com/doi/10.1046/j.1365-313X.2001.01173.x/full
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