Boosting plant defenses using silicon fertilization

View the project final report

• 2015 annual report
• 2016 annual report

Commodities

• Agronomic: corn, soybeans
• Vegetables: tomatoes

Practices

• Crop Production: fertilizers
• Pest Management: cultural control, integrated pest management

Insect herbivores cause major economical loses in the northeast region. Growers are therefore in constant need of new sustainable practices to diminish crop loses and increase yield. Upon damage, plants are able to activate the production of toxic defense compounds that can poison or reduce the growth of insect attackers. Here we are proposing to use silicon fertilization to enhance the endogenous plant defense mechanisms as an strategy to reduce herbivore damage and increase yield. We are specifically proposing to test 1) the protective effect of silicon fertilization against herbivorous insects in different crops under greenhouse and field conditions, and 2) to elucidate the means by which silicon affects insect herbivores. Our preliminary results indicate that tomato plants supplemented with silicon produced significantly greater number of glandular trichomes and had higher levels of herbivore-defensive proteins upon feeding by the fall armyworm larvae compared with non-supplemented controls. In this project we would like to extend these experiments to other vegetable crops with the long term goal of developing a new agronomical practice to be included in integrated pest management programs in the northeast of the US. This proposal addresses the sustainable agricultural topic of pest management and fits the SARE stewardships of profitability and quality of life for farmers. The results of this project will be available to the public through scientific publications, oral and poster presentation in scientific meetings and will be also available online at the Penn State Entomology website.

1) To determine the effect of Si fertilization on yield and plant resistance to herbivores under greenhouse and field conditions.

2) To determine the effect of silicon fertilization and insect damage on the density of trichomes and mineral composition of plant leaves.

3) To determine the effect of Si-fertilized plants on caterpillar growth, mandible wear and integrity of the insect’s gut protective membrane.