Ecological fitness of brown planthopper, Nilaparvata lugens (Stål), to rice nutrient management

Abstract

Introduction: The brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), is a notorious insect pest of rice. Nutrient supplementation can alter plant biochemical compositions which may indirectly affect on ecological fitness parameters of its insect pest. However, few findings are available on nutrient-induced ecological fitness of BPH and relationship of BPH fitness parameters with its host rice plant biochemical contents. Methods: We studied the main and interaction effects of nitrogen (N), phosphorus (P), and potassium (K) inputs on BPH fitness, as measured by the following variables: nymph survival, nymphal duration, adult body weight, and its survival. Brown planthopper fitness parameters were regressed as function of rice plant (Oryza sativa) biochemical composition. A completely randomized design with four replications in a factorial scheme was used considering N, P, and K levels as factors. Results: Nitrogen application to the host rice plants provided greater survival and enhanced body weight of BPH. The nymphal duration was found to decrease with N subsidy that caused shorter generation time of BPH. Nitrogenous compounds N and soluble protein (SP), total free sugar (TFS), and silicon (Si) content in rice plant tissue correlated strongly with all fitness traits of BPH. Nitrogen, SP, and TFS associated positively with BPH survival and body weight, while negatively with nymphal duration. In contrast, Si had negative correlation with BPH survival and body weight, but positive with nymphal duration. Phosphorus supplementation to host plant contributed to increase BPH body weight. Relationships of P with all parameters of BPH were weak except body weight which was highly significant and positive. Interaction between N and P inputs demonstrated significant effect on BPH body weight. Application of K had no significant effect on BPH survival and development. Regression analysis did not detect significant relationship of BPH fitness parameters with plant tissue content of K. Conclusions: The results suggest that BPH ecological fitness characters were improved after N and P fertilization to rice plants which are associated with biochemical content of rice plant. Therefore, N and P inputs should be used judiciously in rice cultivation to keep BPH ecological fitness potential at minimum level.

Evaluation of Rice Landraces for Brown Planthopper Resistance Based on Phenotypic Reactions and Biochemical Attributes

“…However, some workers found that higher level of K was associated with a lower population of BPH possibly due to the reduced level of RS and TFA in K rich rice cultivars (Vanitha et al 2011). Correlation and PCA strongly boosted these obtained results and the possible mechanisms were also supported by Rashid et al (2017b) and Yin et al (2005). The phenolic compounds were found to be the feeding deterrents to BPH in rice and generally have a positive correlation with host plant resistance (Singh 2004).…”

“…Moreover, Rashid et al (2017b) linked higher K level with a lower level of TFA in the rice plants and observed the increment of both the compounds after BPH feeding.…”

Resistance Monitoring of Nilaparvata lugens Stall against Pymetrozine Insecticide with Determination of Diagnostic Concentrations

“…These differences in resistance levels in geographically different populations may reflect natural variation between populations. According to Rashid et al (2017), population abundance and insect pest dynamics is dependent on ecological fitness parameters, such as survival rate. Based on the slope value, the one with the lowest slope was at the Mungkid location.…”

Recent Strategies for Detection and Improvement of Brown Planthopper Resistance Genes in Rice: A Review

“…Currently, the insect pest has been described as the most damaging rice pest in Asia [ 5 , 6 , 7 , 8 ]. Heavy infestation by BPH can result to direct and indirect yield losses of 20–80% in sensitive cultivars [ 9 , 10 , 11 , 12 , 13 ]. When the pest damage becomes established, it is very difficult to control and, thus, yield reduction is certain [ 14 ].…”

“…The factors that favour BPH development include the adoption of high-yielding BPH-sensitive varieties to replace traditional resistant ones in recent years [ 15 ], higher humidity (greater than 80%), temperature of about 25 to 32 °C, and application of nitrogenous fertiliser beyond the recommended rate [ 16 ]. Others are higher plant density, continuous submergence of the host in the field and indiscriminate application of pesticide at the early development of the host, which destroys their natural enemies [ 12 , 16 , 17 ]. Attack by BPH causes a reduction in photosynthetic rate, leaf area, chlorophyll content, nitrogen level of leaf and stem and dry matter accumulation in rice varieties that are susceptible [ 18 ].…”