Laboratory and Greenhouse Assessments of Steinernema Carpocapsae With Three Adjuvants on Chrysodeixis Includens

Journal of Nematology

Volume 57 (2025): Issue 1 (February 2025)

By:

Minling Zhang, Nathan R. Spaulding, Gadi V.P. Reddy and David I. Shapiro-Ilan

Open Access

|Sep 2025

Figures & Tables

(A) A cage containing soybean plants used for the trials in the greenhouse; the circle over the plants shows where the survival of entomopathogenic nematodes (EPNs) on soybean leaves was examined. (B) A larva of Chrysodeixis includens killed by Steinernema carpocapsae (ALL strain) within 24 hr in the greenhouse; the color change began from the anus, and EPNs were found after dissection. (C) Adults of Steinernema carpocapsae (ALL strain) in the body cavity of a Chrysodeixis includens larvae taken from the greenhouse trial.

Entomopathogenic nematode (EPN) suspensions after application on soybean leaves. EPN suspension with water only (A) displays numerous water droplets on the leaf. EPN suspensions with dish soap (B), dish soap combined with vegetable oil (C), and Southern Ag Surfactant (D) show the suspensions evenly distributed on the leaves due to the use of adjuvants.

Mortality (% ± SEM) of fifth instars of Chrysodeixis includens caused by Steinernema carpocapsae (ALL strain) with adjuvants under greenhouse conditions_

Trial	First	Second		Third
Temperature (°C)^a	19 (10–32)	24 (22–39)		24 (22–38)
RH (%)^a	81 (74–90)	81 (44–95)		70 (32–83)
Plant stage	3^rd trifoliolate	Full flowering		Beginning pod
High (cm)	7.6	40.6		43.2

Insect dead (hr)	72	24	72	24	72

EPN 40^b	100.0 ± 0.0 a	19.0 ± 13.2 ab	80.1 ± 8.8 b	7.4 ± 3.7 b	63.0 ± 9.8 b
EPN+S 40	100.0 ± 0.0 a	48.1 ± 19.6 a	100.0 ± 0.0 a	18.5 ± 13.4 ab	77.8 ± 6.4 ab
EPN+S+O 40	100.0 ± 0.0 a	38.4 ± 3.2 a	100.0 ± 0.0 a	48.1 ± 13.4 a	88.9 ± 0.0 a
EPN+SAg 40	100.0 ± 0.0 a	43.5 ± 6.0 a	96.7 ± 3.3 a	11.1 ± 6.4 ab	74.1 ± 7.4 ab
EPN+SAg 20	95.8 ± 7.2 a	14.9 ± 3.7 ab	70.1 ± 4.4 b	3.7 ± 3.7 b	59.3 ± 3.7 bc
EPN+SAg 10	80.0 ± 17.3 b	13.2 ± 8.3 ab	61.4 ± 5.0 b	0.0 ± 0.0 b	32.6 ± 3.4 c
Water	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 d
Water+S	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 d
Water+S+O	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 d
Water+SAg	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 d
F-Value (9, 20)	205.57	7.80	171.92	5.50	83.39
P-Value	<.0001	<.0001	<.0001	0.0007	<.0001

Number (± SEM) of viable Steinernema carpocapsae (ALL strain) per soybean leaf after application under greenhouse conditions_

Trail	First				Second			Third
Sampling time (hr)	24	48	120	168	24	48	96	24	48	96
Temperature (°C)^a	10–32	8–32	5–32	5–32	22–39	20–39	20–39	22–38	21–38	20–42
RH (%)^a	74–90	42–90	42–90	42–90	44–95	44–99	44–99	32–83	26–88	24–94
EPN 40^b	19.7 ± 3.4 a	3.7 ± 0.9 ab	0.0 ± 0.0 b	0.0 ± 0.0 a	51.7 ± 5.8 ab	10.3 ± 8.1 ab	4.8 ± 1.3 ab	50.0 ± 10.2 a	13.3 ± 7.5 a	0.8 ± 0.4 a
EPN + S 40	20.3 ± 10.9 a	13.5 ± 3.0 a	0.5 ± 0.3 b	0.5 ± 0.3 a	28.8 ± 6.7 ab	12 ± 5.5 ab	4.8 ± 3.1 ab	35.2 ± 25.8 ab	4.7 ± 1.6 ab	0.3 ± 0.2 a
EPN + S+O 40	64.2 ± 36.5 a	15.3 ± 5.7 a	10. 3 ± 4.6 a	0.0 ± 0.0 a	65.2 ± 19.0 a	45.8 ± 5.4 a	9.0 ± 2.8 a	44.8 ± 12.6 a	3.2 ± 1.5 ab	1.2 ± 1.2 a
EPN + SAg 40	9.5 ± 1.8 ab	2.0 ± 0.5 bc	0.5 ± 0.5 b	0.0 ± 0.0 a	33.7 ± 12.9 ab	9.0 ± 3.5 ab	3.7 ± 2.0 ab	21.3 ± 12 ab	5.5 ± 2.4 ab	0 ± 0 a
EPN + SAg 20	8.3 ± 4.4 ab	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 a	7.5 ± 4.5 b	4.5 ± 3.0 b	0 .0 ± 0.0 b	6.7 ± 2.4 ab	1.0 ± 0.3 ab	0 ± 0 a
EPN + SAg 10	0.7 ± 0.7 b	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 a	4.7 ± 2.4 b	2.8 ± 1.6 b	0.0 ± 0.0 b	1.8 ± 1.4 b	0.0 ± 0.0 b	0 ± 0 a
F-Value (5, 12)	6.59	22.41	16.45	3.32	5.41	4.15	8.40	4.96	3.60	1.14
P-Value	0.0036	<.0001	<.0001	0.0412	0.0078	0.0202	0.0013	0.0108	0.0321	0.3938

Mortality (% ± SEM) of fifth instars of Chrysodeixis includens caused by Steinernema carpocapsae (ALL strain) with adjuvants at 24 and 72 hr under laboratory conditions (25 °C, 85% RH)_

Exposure (hr)	1		4		8		24
Insect dead (hr)	24	72	24	72	24	72	24	72
EPN^a	5.0 ± 2.2 ab	38.3 ± 4.8 b	8.3 ± 4.0 bc	40.0 ± 6.8 b	0.0 ± 0.0 b	63.3 ± 1.2 a	23.3 ± 4.9 b	98.3 ± 1.7 a
EPN+S	8.3 ± 4.0 ab	48.3 ± 6.5 ab	16.7 ± 3.3 b	61.7 ± 7.9 a	15.0 ± 7.2 a	80.0 ± 5.8 a	21.7 ± 5.4 b	98.3 ± 1.7 a
EPN+S+O	10.0 ± 6.3 a	61.7 ± 7.0 a	23.3 ± 4.2 a	66.7 ± 6.1 a	23.3 ± 5.6 a	76.7 ± 6.7 a	51.7 ± 4.0 a	100.0 ± 0 a
EPN+SAg	5.0 ± 3.4 ab	38.3 ± 5.4 b	11.7 ± 6.0 abc	55.0 ± 7.6 ab	10.0 ± 2.6 a	75.0 ± 6.2 a	25.0 ± 3.4 b	98.3 ± 1.7 a
Water	0.0 ± 0.0 b	0.0 ± 0.0 c	0.0 ± 0.0 c	0.0 ± 0.0 c	0.0 ± 0.0 b	0.0 ± 0.0 b	0.0 ± 0.0 c	1.7 ± 1.7 b
Water+S	0.0 ± 0.0 b	0.0 ± 0.0 c	0.0 ± 0.0 c	1.9 ± 1.6 c	0.0 ± 0.0 b	0.0 ± 0.0 b	0.0 ± 0.0 c	0.0 ± 0.0 b
Water+S+O	0.0 ± 0.0 b	1.7 ± 1.7 c	0.0 ± 0.0 c	0.0 ± 0.0 c	0.0 ± 0.0 b	3.5 ± 2.2 b	0.0 ± 0.0 c	0.0 ± 0.0 b
Water+SAg	0.0 ± 0.0 b	1.7 ± 1.7 c	0.0 ± 0.0 c	0.0 ± 0.0 c	0.0 ± 0.0 b	1.9 ± 1.9 b	0.0 ± 0.0 c	0.0 ± 0.0 b

F-Value (7, 40)	4.19	58.87	12.08	64.56	11.74	42.17	40.71	457.83
P-Value	0.0015	<.0001	<.0001	<.0001	<.0001	<.0001	<.0001	<.0001

DOI: https://doi.org/10.2478/jofnem-2025-0034 | Journal eISSN: 2640-396X | Journal ISSN: 0022-300X

Journal RSS Feed

Language: English

Submitted on: Mar 1, 2025

Published on: Sep 17, 2025

Published by: Society of Nematologists, Inc.

In partnership with: Paradigm Publishing Services

Publication frequency: 1 times per year

Keywords:

Related subjects:

© 2025 Minling Zhang, Nathan R. Spaulding, Gadi V.P. Reddy, David I. Shapiro-Ilan, published by Society of Nematologists, Inc.
This work is licensed under the Creative Commons Attribution 4.0 License.

Previous article Volume 57 (2025): Issue 1 (February 2025)

Laboratory and Greenhouse Assessments of Steinernema Carpocapsae With Three Adjuvants on Chrysodeixis Includens

Figures & Tables

Figure 1:

Figure 2:

Mortality (% ± SEM) of fifth instars of Chrysodeixis includens caused by Steinernema carpocapsae (ALL strain) with adjuvants under greenhouse conditions_

Number (± SEM) of viable Steinernema carpocapsae (ALL strain) per soybean leaf after application under greenhouse conditions_

Mortality (% ± SEM) of fifth instars of Chrysodeixis includens caused by Steinernema carpocapsae (ALL strain) with adjuvants at 24 and 72 hr under laboratory conditions (25 °C, 85% RH)_

Paradigm

My account