Introduction
⌅Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) is a shrub species that stands out for its agronomic parameters and nutritional quality (Botero-Londoño et al. 2019Botero-Londoño J.M., Gómez-Carabalí, A. & Botero-Londoño, M.A. 2019. Rendimiento, parámetros agronómicos y calidad nutricional de la Tithonia diversifolia con base en diferentes niveles de fertilización. Revista Mexicana de Ciencias Pecuarias, 10 (3): 789 - 800, ISSN: 2448-6698. https://doi.org/10.22319/rmcp.v10i3.4667. and Vargas et al. 2022Vargas, V.T., Pérez, P., López, S. & Castillo, E. 2022. Producción y calidad nutritiva de Tithonia diversifolia (Hemsl) A. Gray en tres épocas del año y su efecto en la preferencia por ovinos Pelibuey. Revista Mexicana de Ciencias Pecuarias, 13 (1): 240-257, ISSN: 2448-6698. https://doi.org/10.22319/rmcp.v13i1.5906.). It constitutes an invaluable forage potential in milk (Gallego et al. 2014Gallego, L., Mahecha, L. & Angulo, J. 2014. Potencial forrajero de Tithonia diversifolia Hemsl. A Gray en la producción de vacas lecheras. Agronomía Mesoamericana, 25(2): 393-403, ISSN: 2215-3608. https://doi.org/10.15517/am.v25i2.15454.) and meat (Iraola et al. 2022Iraola, J., García, Y., Fraga, L.M., Gutiérrez, D., Cino, D.M., Barros-Rodríguez, M., Hernández, J.L. & Albelo, D. 2022. Comportamiento productivo de machos vacunos en silvopastoreo con Tithonia diversifolia. Livestock Research for Rural Development, 34(11): Artículo #100, ISSN: 2521-9952. Disponible en: http://www.lrrd.org/lrrd34/11/34100dira.html.) production. These intensive silvopastoral systems also have an important role in reducing physical and biological soil degradation (Giraldo and Chará 2022Giraldo N.V. & Chará J. 2022. Efecto de los sistemas silvopastoriles intensivos en la reducción de la degradación física y biológica del suelo. Livestock Research for Rural Development, 34: Article #17, ISSN: 2521-9952. Disponible en: http://www.lrrd.org/lrrd34/3/3417vicky.html.), making them even more attractive and resilient.
Research carried out at the Institute of Animal Science of the Republic of Cuba by a multidisciplinary team, led by Ruiz et al. (2016)Ruiz, T.E. Alonso, J., Febles, G.J., Galindo, J.L., Savón, L.L., Chongo, B.B., Torres, V., Martínez, Y., La O, O., Gutiérrez, D., Crespo, G.J., Cino, D.M., Scull, I. & González, J. 2016. Tithonia diversifolia: I. Estudio integral de diferentes materiales para conocer su potencial de producción de biomasa y calidad nutritiva. Avances en Investigación Agropecuaria, 20(3): 63-82, ISSN: 0188-7890., makes available a group of outstanding materials, which biomass can be used for grazing (Ruiz et al. 2023aRuiz, T.E., J. Febles, G., Alonso, J., Torres, V., Valenciaga, N., Galindo, J., Mejías, R. & Medina, Y. 2023a. Comportamiento agronómico en pastoreo de materiales destacados de Tithonia diversifolia en Cuba. Avances en Investigación Agropecuaria, 27(1): 136-145, ISSN: 2683-1716. https://doi.org/10.53897/RevAIA.23.27.26.) as well as for cutting (Ruiz et al. 2024Ruiz, T.E., Febles, G. J., Torres, V., Lok, S., Valenciaga, N., Rodríguez, B., Báez, N. & Medina, Y. 2024. Frecuencia de corte en la producción de biomasa de materiales destacados de Tithonia diversifolia identificados en Cuba. Tropical Grasslands - Forrajes Tropicales, 12(2): 106-115, ISSN: 2346-3775. https://doi.org/10.17138/TGFT(12)106-115.). The ICA CUBA Oc-10 variety stands out for its agronomic attributes, in both aspects, although with greater emphasis on grazing. Knowing its phytosanitary performance is important in order to extend this plant because of its benefits. Studies by Rodríguez et al. (2022)Rodríguez, Z., Milán, E., Reyes, S. & Morales, Y. 2022. Tithonia diversifolia como planta reservorio de biorreguladores en los pastos y forrajes. TD-27. Simposio Internacional de Tithonia diversifolia. Memorias AGROPAT 2022. Centro de Convenciones Plaza América, Varadero, Matanzas, Cuba. ISBN: 978-959-7171-86-7. assert that T. diversifolia is a plant that serves as a reservoir for predators and parasitoids. Based on this idea, this study was carried out to evaluate the beneficial fauna associated with a silvopastoral system (SSP) of tithonia cv. ICA CUBA Oc-10 together with improved and natural grasses intended for bull fattening, and to know its role in the incidence of pest insects.
Materials and Methods
⌅Location
⌅The research was conducted over three years in experimental areas of the Institute of Animal Science (ICA), located at 22º 53' North, 82º 02' West and 92 m a.s.l., in San José de las Lajas, Mayabeque province, in the Republic of Cuba.
Experimental area
⌅It consisted of 10 ha of improved grasses (Cynodon nlemfuensis) and natural grasses (Paspalum notatum, Sporobolus indicus, Dichantium sp.), divided into two five-hectare systems: one with grasses and another with a silvopastoral system (SSP) of grasses and tithonia, associated in 100% of the area, productively intended to fattening Cuban Siboney bovine males.
Methodology for establishing tithonia SSPs
⌅Tithonia was sown on carbonated brown soil (Hernández et al. 2019Hernández, A., Pérez, J.M., Bosch, D. & Castro, N. 2019. La clasificación de los suelos de Cuba: énfasis en la versión de 2015. Cultivos Tropicales, 40(1): a15 - e15, ISSN: 1819-4087. Disponible en: http://ediciones.inca.edu.cu/index.php/ediciones/article/view/1504.), according to the concepts and methodologies developed by Ruiz and Febles (1999)Ruiz, T.E. & Febles, G. 1999. Sistemas silvopastoriles. Conceptos y tecnologías desarrollados en el Instituto de Ciencia Animal de Cuba. EDICA. Instituto de Ciencia Animal. La Habana. Cuba. pp. 43. and Ruiz et al. (2006)Ruiz, T.E., Febles, G., Jordán. J., Castillo, E., Mejías R., Crespo, G., Chongo, B., Delgado, D., Alfonso, H., Escobar, A. & Ramírez. R. 2006. Conceptos y Tecnologías desarrolladas en el Instituto de Ciencia Animal. En: Fisiología. producción de biomasa y sistemas silvopastoriles en pastos tropicales. Abono orgánico y biogás. Tomo II. Edición EDICA. Cuba. 136 p. by preparing soil strips in grassland areas. The registered variety of T. diversifolia cv. ICA CUBA Oc10 was used for this purpose, which was proposed by Ruiz et al. (2010)Ruiz, T.E., Febles, G., Torres, V., González, J., Achang, G., Sarduy, L. & Díaz, H. 2010. Evaluación de materiales recolectados de Tithonia diversifolia (Hemsl.) Gray en la zona centro-occidental de Cuba. Revista Cubana de Ciencia Agrícola, 44(3): 291-296, ISSN: 0034-7485. for its use in grazing.
Experimental procedure
⌅For the studies of the associated entomofauna, a stratified sampling in five blocks was implemented after the promotion of the silvopastoral system with Tithonia diversifolia. In the center of each block, the representative sampling area was defined, according to the methodology proposed by CIBA-GEIGY (1981)CIBA-GEISY 1981. Manual para ensayos de campo en protección vegetal. Segunda edic. revisada y ampliada. Werner Püntener, División Agricultura. Switzerland. 205 p..
At three contrasting climatic moments of the year (January, May and September), a sample of 20 raids was taken in each block using the entomological net per each plant component (tithonia and base grass) for a total of 10 samples (five in the tithonia and five in the base grass). Five samples were taken in the control area, established only with grasses. All were individualized in plastic bags with their respective identifications and transferred to the Pest Management Laboratory of the Pastures Department of ICA for processing and taxonomic identification. A stereoscopic microscope, entomological collections and related dichotomous keys were used for this. Phytophagous insects, visiting organisms and associated beneficial fauna (bioregulators) were identified in each study area according to the assignment of functional groups according to Metcalf and Flint (1965)Metcalf, C.L. & Flint, W.P. 1965. Insectos destructivos e insectos útiles: sus costumbres y su control. Instituto Cubano del Libro. La Habana, Cuba, 1208 p., Triplehorn and Johnson (2005)Triplehorn, C.A. & Johnson, N.F. 2005. Borror and DeLong's lntroduction to the Study of lnsects. Thomson Brooks/Cole, USA, 864 p., Seventh Edition, ISBN 003-096835-6. https://www.academia.edu/30669150/Borror_and_Delong_2005_Study_of_Insects., Mancina and Cruz (2017)Mancina, C.A. & Cruz, D.D. 2017. Diversidad biológica de Cuba: métodos de inventario, monitoreo y colecciones biológicas. Editorial AMA, La Habana, 480 p. ISBN: 978-959-300-130-4 (versión digital). and World Spider Catalog (2020)World Spider Catalog 2020. World Spider Catalog. Version 21.5. Natural History Museum Bern. https://doi.org/10.24436/2. . In addition, the damage level caused by pest insects in each plant component was evaluated according to Calderón (1982)Calderón, M. 1982. Evaluación del daño causado por insectos. En: J. M. Toledo (Ed.). Manual para la Evaluación Agronómica. CIAT, Red Internacional de Evaluación de Pastos Tropicales. Cali, Colombia. p. 80.. The climatic performance of the area is shown in figure 1.
Statistical analysis
⌅During the three years of study, for the variables of the associated arthropod fauna (visitors, phytophagous and bioregulators) the theoretical assumptions of the analysis of variance, normality of errors by the Shapiro Wilk (1965)Shapiro S.S. & Wilk M.B. 1965. An analysis of variance test for normality (complete samples). Biometrika, 52: 591-611. https://doi.org/10.1093/biomet/52.3-4.591. test, Pearson correlation analysis and Mauchly (1940)Mauchly, J. 1940. Significance test of sphericity of a normal n-variate distribution. The Annals of Mathematical Statistics, 29: 204-209, ISSN: 2168-8990. http://dx.doi.org/10.1214/aoms/1177731915. sphericity were tested. Since these assumptions were not fulfilled, the methodology proposed by Gómez (2019)Gómez, S. 2019. Contribución estadística para el análisis de medidas repetidas en el tiempo en el sector agropecuario. Tesis presentada en opción al grado científico de Doctor en Ciencias Veterinarias. Mayabeque, Cuba. was used. Data were processed with the help of Proc GLIMMIX from SAS. Plant community, year, interaction and plant community per year were considered as fixed effects. The intercept was considered as random effects and the plant nested in the month was used as the subject. The variance-covariance structures compound symmetry (CS), autoregressive of order 1 Ar (1), unstructured (UN), variance components (CV) and topeplitz (Toep) were tested. The latter obtained the smallest selection criteria values. Data were adjusted to the Gamma distribution with link function (log). For the comparison of means, the Tuckey-Kramer fixed range test (Kramer 1956Kramer, C.Y. 1956. Extension of multiple range tests to group means with unequal numbers of replications. Biometrics, 12: 307 - 310, ISSN: 1541-0420. https://doi.org/10.2307/3001469.) was used for p<0.05. For data processing, the statistical package SAS (2013)SAS. 2013. Sistema de análisis estadístico. Universidad de Nebraska. Versión 9.3. SAS/STAT 9.1. Copyright, SAS Institute Inc., Cary, NC, USA. ISBN 1-59047-243-8., version 9.3, was used.
Results and Discussion
⌅Figure 2 shows the performance of the relative abundance of the arthropod fauna associated with each plant component at the different sampling times. In May, there was equity in the associated organisms with a similar percentage (33 %) in each evaluated plant component. In September, the abundance was slightly higher in the control area (41.90 %) with no differences with those collected in the SSP area of tithonia (31.43 %). It was lower in base grass (26.67 %). In January, it had an inferior performance in the SSP with tithonia (29.33 %), and it was slightly higher in the base grass (34.60 %) and in the control area with grasses only (36.07 %), but with no statistical differences among them.
September was the most representative of the associated entomofauna. This performance must have been subjected to the incidence of climatic factors during the studied period (figure 1). At the beginning of May, when the sampling was carried out, the dry season became more severe (<50 mm of monthly precipitation). Therefore, it is assumed that the insect fauna was reduced, as there were no turgid pastures and quality biomass that would keep them active in the area. In September, climatic conditions favored the appearance of insects with diverse habits. Rains became stable and temperatures were warmer, conditions that favor the increase of these organisms. In January, rains are scarce and temperatures are cooler, sometimes falling below 20 ºC. During this time, many insects have lower levels of their population and fewer generations are obtained. It is important to highlight the decrease in the accumulated rainfall that occurred in 2023 in the study area, which, never reached 200 mm on the rainy days of the month, compared to previous years (2021 and 2022), when records of 300 and even 400 mm were reached. The rainiest year was 2022, in which 480 mm were reached in June, with 14 days of rain. This climatic perfomance is undoubtedly reflected in the performance of the associated insects (Doria-Bolaños et al. 2021Doria-Bolaños, M., García-Gonzales, P. & Fachin-Ruiz, G. 2021. Estudio de diversidad de la entomofauna en el Centro de Biodiversidad de la Universidad Nacional de San Martín. Revista Agrotecnológica Amazónica, 1(2): 15-26, ISSN: 2710-0510. https://doi.org/10.51252/raa.v1i2.177. ).
In the study carried out over three consecutive years (2021, 2022 and 2023) with the same sampling methodology, there was significant interaction between the plant community and the year, for all variables (table 1). In this case, the lower proportion of phytophagous species associated with the SSP with tithonia (9.97) stands out compared to the base grass (19.13) and control area with grasses (20.14). In turn, there was higher proportion of bioregulatory species associated with these plant communities, with higher values in tithonia (9.63) compared to the base grass (5.94) and the control (3.84). As previously stated, visitors influence the entire system indiscriminately, with greater emphasis on the flowering stage of tithonia. In 2023, which is the fourth year of promoting the SSP, there was a significant decrease in phytophagous species associated with the SSP with tithonia (3.70), which significantly differs from the base grass (9.18) and the control area (12.52). An increase or stability of the associated beneficial fauna (9.81, 4.82 and 5.26) was also recorded for tithonia, base grass and control area, respectively, although without statistical differences among these plant communities.
Variables | Community years | Tithonia in SSP | Base grass in SSP | Control (grasses) | EE (±) Sign. |
---|---|---|---|---|---|
Visitors | 2021 | 1.99b (7.32) | 2.36a (10.56) | 2.38a (10.77) | 0.14 p=0.0005 |
2022 | 2.33a (10.24) | 2.01b (7.44) | 2.11ab (8.28) | ||
2023 | 1.96b (7.11) | 1.90b (6.66) | 1.56c (4.76) | ||
Phytophagous | 2021 | 2.30c (9.97) | 2.95a (19.13) | 3.00a (20.14) | 0.16 p<0.0001 |
2022 | 2.46bc (11.75) | 2.43bc (11.33) | 2.62b (13.72) | ||
2023 | 1.31d (3.70) | 2.22c (9.18) | 2.53bc (12.52) | ||
Biorregulators | 2021 | 2.26a (9.63) | 1.78ab (5.94) | 1.36b (3.88) | 0.23 p=0.0083 |
2022 | 1.68ab (5.38) | 1.72ab (5.56) | 1.87ab (6.46) | ||
2023 | 2.28a (9.81) | 1.57ab (4.82) | 1.66ab (5.26) |
abc Different letters in each variable indicate significant differences p<0.05 (Kramer 1956Kramer, C.Y. 1956. Extension of multiple range tests to group means with unequal numbers of replications. Biometrics, 12: 307 - 310, ISSN: 1541-0420. https://doi.org/10.2307/3001469.).
(…) Values in parenthesis indicate data transformed by log link function
These results coincide with studies by Ochoa et al. (2017)Ochoa, D.E, Lopera, J.J., Márquez, S.M., Calle, Z., Giraldo, C., Chará, J. & Murgueitio, E. 2017. Los sistemas silvopastoriles intensivos contribuyen a disminuir el ataque de chupadores en pasto kikuyu (Cenchrus clandestinus). Livestock Research for Rural Development, 29: Article #82, ISSN: 2521-9952. Disponible en: http://www.lrrd.org/lrrd29/5/lope29082.html., who found 54 % less Collaria oleosa (Hemiptera: Miridae) and 59 % less Draeculacephala sp. (Hemiptera: Cicadellidae) in the associated plants in the silvopastoral systems compared to the single-crop area with the kikuyu grass (Cenchrus clandestinus), which experienced the greatest damage. Therefore, the silvopastoral systems kept the populations of sucking insects under control. The authors confirmed that the larger the single-crop area, the greater the incidence and damage by phytophagous insects.
A marked influx of bioregulatory organisms associated with the SSP with tithonia was observed, compared to the control area, with grasses only. The SSP with the association of plants of different sizes and architectures creates various refuge and nectar sites for the habitat of multiple organisms, such as the associated beneficial fauna. This, without a doubt, constitutes a favorable indicator, which is confirmed in this study, as it contributes to the comprehensive management of pest insects in the agroecosystem. Studies in Cuba by Rodríguez et al. (2022)Rodríguez, Z., Milán, E., Reyes, S. & Morales, Y. 2022. Tithonia diversifolia como planta reservorio de biorreguladores en los pastos y forrajes. TD-27. Simposio Internacional de Tithonia diversifolia. Memorias AGROPAT 2022. Centro de Convenciones Plaza América, Varadero, Matanzas, Cuba. ISBN: 978-959-7171-86-7. recommend T. diversifolia associated with pastures and forages, which promotes ecosystem services and increases the resilience of livestock agroecosystems.
Results in tithonia confirm that silvopastoral systems achieve the stability of phytophagous and bioregulatory organisms over time, which prevents economic and physiological damage to the main crop. This was also reported in similar studies by Valenciaga et al. (2019Valenciaga, N., Herrera, M. & Ruiz, T.E. 2019. Heteropsylla cubana Crawford (Hemiptera: Psyllidae) en sistemas silvopastoriles con Leucaena leucocephala (Lam.) de Wit (Fabaceae) en condiciones de Cuba. En: Castaño, K., Chará, J., Giraldo, C. & Calle, Z., (eds). Manejo integrado de insectos herbívoros en sistemas ganaderos sostenibles. ISBN 978-958-9386-93-4 Digital, CIPAV, Cali Colombia, 306 p. , 2020)Valenciaga, N., Ruiz, T.E., Ramírez, L. & Parsons, D. 2020. Abundance of Heteropsylla cubana populations and it natural enemies Leucaena leucocephala agroecosystems. Livestock Research Rural Development, 32: Artículo #177, ISSN: 2521-9952. Disponible en: http://www.lrrd.org/lrrd32/11/nvale32177.html. and Ruiz et al. (2023b)Ruiz, T.E., Febles, G. J., Alonso, J. & Valenciaga, N. 2023b. El árbol y su efecto en la estabilidad productiva vegetal en un Sistema Silvopastoril. Pp. 54-57. En: Rivera J., Viñoles C., Fedrigo J., Bussoni A., Peri P., Colcombet L., Murgueitio E., Quadrelli A. & Chará J. (Eds.) Sistemas Silvopastoriles: Hacia una Diversificación Sostenible. CIPAV. Cali, Colombia. ISBN 978-628-95190-5-1. in diversified silvopastoral systems with leucaena-Guinea. In this case, the SSP with the association of plants of different sizes and architectures, creates various refuge and nectar sites for the habitat of multiple organisms such as the associated beneficial fauna, which makes it possible to reduce phytophagous insects and damage associated with the base grass under the SSP with tithonia.
Conclusions
⌅There is a marked influx of bioregulatory organisms associated with the SSP with tithonia and base grass compared to control area, with grasses only. An increase or stability was achieved with the years of exploitation of the system. This is a favorable indicator, which increases zoological and functional biodiversity, contributes to the integral management of insect pests and guarantees sustainability of the agroecosystem.
It is recommended to promote increasingly diversified areas, such as silvopastoral systems, and avoid the extension of single-crops to favor the balance between phytophagous and bioregulatory species at levels that are not harmful.