ABSTRACT White-backed planthopper, Sogatella furcifera Horváth (Hemiptera: Delphacidae) is a migratory and serious pest of rice crop worldwide including Pakistan. The current experiment was carried out to assess the antixenosis and antibiosis level of flfteen rice genotypes against S. furcifera under greenhouse conditions. In antixenosis studies, proportion of nymphs and adults settled was recorded in relation to control. Less preferred varieties by nymphs were RPP49 (3.80), N22 (5.60), IR 64 (6.20), IR 72 (6.60), Basmati Pak (6129) (5.40), and Super Basmati (5.00) as compared to TN1 (12.00). Lower number of eggs were laid on RPP49, N22, IR 64, Super Basmati and PKBB 8. Based on feeding marks the genotypes ranked from highest to lowest as RPP49, N22, IR 64, IR 72 and Basmati Pak. In antibiosis tests, RPP49, N22, IR64, IR 72, Super Basmati and Basmati Pak varieties performed well as compared to TN1. Minimum feeding rate (47.8 mm2) was recorded on RPP49 followed by N22, IR 64, IR74, Basmati Pak, Super Basmati, PKBB 8, PK 10684 and PK 10436 as compared to TN1(470.8 mm2). The results revealed that RPP49 emerged as the new resistant source against S. furcifera. Super Basmati, Basmati Pak have shown a moderate level of resistance while PKBB 8, PK 10684 and PK 10436 are new varieties with a moderate level of resistance to S. furcifera which can be used as resistance source in breeding programs against S. furcifera.

RESUMEN La falsa chicharrita del arroz, Sogatella furcifera (Horváth) (Hemiptera: Delphacidae) es una plaga migratoria y grave para los cultivos de arroz en todo el mundo, incluso Pakistán. El presente experimento se llevó a cabo para evaluar el nivel de antixenosis y antibiosis de quince genotipos de arroz contra S. furcifera en condiciones de invernadero. En los ensayos de antixenosis, la proporción de ninfas y adultos asentados se registró en relación con el grupo control. Las variedades menos preferidas por las ninfas fueron RPP49 (3.80), N22 (5.60), IR 64 (6.20), IR 72 (6.60), Basmati Pak (6129) (5.40) y Super Basmati (5.00) en comparación con TN1 (12.00). Se depositó un número menor de huevos en RPP49, N22, IR 64, Super Basmati y PKBB 8. Con base en la huella de alimentación, los genotipos ordenados de mayor a menor fueron RPP49, N22, IR 64, IR 72 y Basmati Pak. En ensayos de antibiosis, las variedades RPP49, N22, IR64, IR 72, Super Basmati y Basmati Pak obtuvieron buenos resultados en comparación con TN1. La menor velocidad de alimentación (47.8 mm2) se observó en RPP49, seguida por N22, IR 64, IR74, Basmati Pak, Super Basmati, PKBB 8, PK 10684 y PK 10436, en comparación con TN1 (470.8 mm2). Los resultados revelaron que RPP49 se ha convertido en la nueva fuente de resistencia contra S. furcifera. Super Basmati y Basmati Pak han mostrado un nivel moderado de resistencia, en tanto que PKBB 8, PK 10684 y PK 10436 son nuevas variedades con nivel moderado de resistencia, capaces de ser utilizadas como fuente de resistencia en programas de reproducción contra S. furcifera.

Abstract Synthetic wood preservatives are the causes of large-scale environmental pollution and few have been withdrawn from the commercial markets in the past years. The present studies focused on determination of naturally present extractives of Ziziphus mauritiana as less toxic wood protectant against subterranean termites. Firstly, natural resistance of Z. mauritiana heartwood against termite was determined by exposing stakes in the field. For the preparation of extractives, air-dried Z. mauritiana heartwood and bark shavings were soaked in 1 liter each of ethyl acetate, hexane, petroleum ether and water in a bottle separately. Different dipping treatment times (36 and 72 hours) at 10, 20 and 30% concentrations of extractives on Populus deltoides wooden stakes were used and stakes were exposed to termites in submerged manner. Combination of extractives in different solvents were included as separate experiment and finally, seasoning prior to extractives application on P. deltoides wooden stakes was also done and stakes were arranged in three replications for each treatment. Maximum mean percent weight loss (81.1%) was observed in case of P. deltoides followed by boiled Z. mauritiana (15.24%) in termite resistance test. Stakes treated with petroleum ether extracts had minimum weight loss alone or in combination with other extract’s solvent in all experiments. Extractives in other solvents followed petroleum ether non-significantly but were significantly different from their respective control treatment, which had the highest weight loss (>60%). Transferring durability using extracts of Z. mauritiana increased resistance of non-durable P. deltoides against termites and extractives could be used as wood preservatives.

ABSTRACT American bollworm (ABW), Helicoverpa armigera (Hubner), is considered as a major pest of cotton, Gossypium hirsutum, all over the globe. Due to its destructive feeding nature and continuous consumption of the same chemicals, it devolved resistant against many insecticides. Therefore, a combined application of bio- and synthetic-pesticide need to evaluate against this pest. The entomopathogenic viruses like nuclear polyhedrosis virus (NPV), a member of baculoviruses, can be the potential candidates for better control against ABW. The present study was conducted to assess the comparative efficacy of NPV and Spinosad 240SC (with the concentration of 250 mL · ha-1) against ABW in the controlled environment. The ABW was treated with different concentrations of NPV and Spinosad separately and in a combination of NPV with 0.1% Spinosad. The results revealed that highest concentrations showed highest mortality (95%) followed by 95%, 92%, 84%, 82% and 78% mortality at 1 × 109, 1 × 108, 1 × 107, 1 × 106 and 1 × 105 POBs, respectively. Spinosad when mixed in diet give 100% mortality at 0.8% followed by 50.87%, 42.10%, 29.82%, 26.31% and 22.80% mortality at 0.4%, 0.2%, 0.1%, 0.5% and 0.025% respectively. The results of this study revealed that microbial control of ABW through NPV is an effective tool. The repeated use of synthetic pesticides caused the resurgence of many insect pests, and this study results would provide useful insight to build a framework for future investigations for the management of many major insect pests.