Dietary macronutrient balance affects reproductive performance across locust lifespans

Monday, November 14, 2022

8:12 AM – 8:24 AM PT

Location: Vancouver Convention Centre, Meeting Room 214

Presenting Author(s)

SM

Sydney Millerwise

Master's Student
Arizona State University
Tempe, Arizona

Co-Author(s)

Stav Talal

Post-Doc
Arizona State University
Chandler, Arizona
PP

Phoenix Pulver

Undergraduate Researcher
Arizona State University
Tempe, Arizona
EG

Emma Goethe

Arizona State University
Tempe, Arizona
GO

Geoffry Osgood

Research Specialist
Arizona State University
Tempe, Arizona
RO

Rick Overson

Arizona State University
Tempe, Arizona
EC

Emily Cossey

Undergraduate Researcher
Arizona State University
Tempe, Arizona
Jon F. Harrison

Professor
Arizona State University
Tempe, Arizona
Arianne Cease

Associate Professor
Arizona State University
Tempe, Arizona

Despite the dramatic population dynamics of locusts, and the well-known impacts of nutritional variation on the ecology and evolutionary life history of locusts and other organisms, few studies have investigated the impacts of dietary macronutrients on locust reproduction. This is due, in part, to the difficulty of measuring reproduction on controlled diets because insects often do not lay eggs when eating artificial diets. We overcame this challenge for locusts by supplementing artificial diets with fresh romaine lettuce that minimally affected the amount of macronutrients consumed but induced reproduction. We reared groups of migratory locusts (Locusta migratoria) from 5th instar through adulthood on one of three artificial iso-caloric diets varying in protein (p):carbohydrate (c) ratios (14p:28c; 21p:21c; 35p:7c). We then put pairs of locusts in cages to measure male and female survival, the number of eggs and egg pods laid, and the total lifetime hatchlings per reproductive pair. We found no effect of diet on male survival, however, females that consumed higher carbohydrate (low p:c) diets had the longest lifespans, and females on higher protein (high p:c) diets lived shorter lifespans. Locusts fed the high p:c diets also laid fewer egg pods than locusts on the other diets. However, we found no effect of diet on the total successful hatchlings over locust lifetimes. These data suggest that despite affecting female lifespans and total opportunities to lay eggs, dietary macronutrient content does not affect the lifetime maximal capacity for reproduction. This work was supported by NSF # 1942054.