Comparative Analysis of Nutritional Indices of Spodoptera frugiperda on Selected Maize Genotypes
Rashmi Vishwakarma *
Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh, India.
S. B. Das
Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh, India.
Sundar Borkar
Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh, India.
*Author to whom correspondence should be addressed.
Abstract
Background: The fall armyworm, Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae), is a notorious and economically important pest due to its wide host range and rapid adaptability. In India, it causes significant damage to maize, sorghum, and sugarcane. Although several studies have focused on maize, information regarding the nutritional suitability of different maize genotypes for S. frugiperda is still limited.
Study Design, Place and Duration: The present investigation was conducted during 2021–2023 at the Biocontrol Research and Production Center, Department of Entomology, College of Agriculture, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur. The experiment was laid out in a Factorial Completely Randomized Design (CRD) with two factors comprising eight maize genotypes and six larval instars of S. frugiperda under controlled laboratory conditions.
Methodology: Nutritional indices of S. frugiperda larvae were assessed on eight maize genotypes viz., CHH-202, CHH-213, CHH-214, HMM-1018, JM-12, JM-216, JM-218, and PHM-1. The nutritional parameters studied included consumption index (CI), relative growth rate (RGR), approximate digestibility (AD), efficiency of conversion of ingested food (ECI), and efficiency of conversion of digested food (ECD).
Results: The results revealed that S. frugiperda successfully developed and reproduced on all tested maize genotypes. Significant variations were observed among genotypes with respect to nutritional indices. Among the tested genotypes, JM-218, JM-12, and HMM-1018 were identified as the least susceptible genotypes. JM-216, CHH-214, and PHM-1 exhibited moderate susceptibility, whereas CHH-213 and CHH-202 were found highly susceptible to S. frugiperda. Higher nutritional index values recorded on CHH-213 and CHH-202 indicated a greater risk of infestation and damage.
Conclusion: The study demonstrated differential suitability of maize genotypes to S. frugiperda and highlighted the importance of nutritional indices in identifying resistant and susceptible genotypes. The findings provide useful information for developing targeted pest management strategies and promoting the use of relatively resistant maize genotypes in sustainable fall armyworm management programs.
Keywords: Spodoptera frugiperda different instar, maize, nutritional indices, least susceptible genotypes, highly susceptible genotypes