Abstract Detail

Biotic and abiotic stress

Robertson, Daniel [1], Julias, Margaret [2], Lee, Shien Yang [3], Cook, Douglas [2].

The underutilized potential of mechanical engineering analyses in botany research.

Food demand continues to rise due to an ever increasing world population while arable farm land continues to decrease due to increased urbanization. Consequently, more crops will have to grow on less land to meet future food demands. Ultra-high yielding crop varieties that are robust to overcrowding and that possess digestible forage that can be converted to second generation biofuels are an attractive solution to this problem. However, stalk lodging (failure of the stalk or plant to remain upright) is a major limiting factor in the development of such crop varieties.
Previous investigations of stalk lodging have primarily been approached from a biological perspective focused on the effects of nutrient uptake, soil composition, weather, husbandry, etc. In contrast, our lab has taken a unique approach to the problem of stalk lodging that is strongly based on mechanical and structural engineering principles. This unique approach has led to several novel insights.
First, structural engineers conducted a multi-year failure analysis of commercial and pre-commercial varieties of lodged corn stalk grown in several international locations. The analysis revealed that over 90% of all corn stalks break in a nearly identical manner. This implies a systematic structural weakness that is common to most if not all current corn varieties. An artificial lodging technique was then developed that mimicked both the loading conditions and failure patterns of naturally lodged corn stalk, thus allowing for detailed laboratory analysis of failure mechanisms. Furthermore, computational finite element models of corn stalk were created and used to investigate mechanical stresses. These tools indicate that geometric features near the node of the plant act as engineering stress concentrators and that they cause the plant to break long before critical tissue stresses are reached. Further structural engineering analyses demonstrated that slight modifications to the local geometry near the node, as opposed to gross modification of stalk diameter and rind thickness, can improve stalk strength by up to 50%. Industry sponsored plant breeders are now in the process of developing breeding approaches to modify these geometric features.
Greater progress on numerous fronts can be made by incorporating mechanical engineering experts into botany research. Such experts have received extensive training in transport theory, mechanical stress analysis, morphology analysis, soil mechanics, and anchoring systems. Leveraging their unique insights, training and contrasting backgrounds may hold the key to solving many prevalent problems in plant science and botany related research.

1 - New York University - Abu Dhabi, Mechanical Engineering, P.O. Box 129188, Abu Dhabi, Abu Dhabi, N/A, NA, UAE
2 - New York University - Abu Dhabi
3 - New York University - Abu Dhabi, Engineering, Po Box 129188, Abu Dhabi, NA, United Arab Emirates

Keywords:
biomechanics
Mechanical Stress
Abiotic stress
engineering
Corn.

Presentation Type: Oral Paper:Papers for Topics
Session: 20
Location: Salon 13/14/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 4:30 PM
Number: 20010
Abstract ID:1017
Candidate for Awards:None