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The diamondback moth, Plutellaxylostella (Lepidoptera; Plutellidae) is one of the most notorious and cosmopolitan insect pests of brassica crops around the world. P. xylostella may causes 90% yield losses in brassica crops . Various control measures have been adopted to manage this pest; however, the most effective control method is the use of synthetic chemical insecticides. Overuse of insecticides have many adverse effects including insecticide resistance, hazardous to environment, long persistency, interfere with food chain. There is an urgent need for alternative control measures which should be effective, environmental friendly and economically safer. Bio pesticides include plant extracts and green synthesized nano-based insecticides are among these measures, which can be useful for the management of P. xylostella . Less work has been carried out on the use of green synthesized plant products against P. xylostella . Therefore, current study has been planned to evaluate the toxicity of plant extracts and green synthesized nano-based plant products against P. xylostella . Eight plants extract (neem, bakain, bitter-gourd, clove, eucalyptus, dathura, garlic and ginger) and their nano-based products (green synthesis silver nanoparticles) were applied in different concentrations against 3 rd larval instars of P. xylostella . Mortality were recorded after 24, 48 and 72 hours of application of treatments. Corrected mortality was calculated using Abbot’s formula and LC 50 values were calculated.

Date palm, is a tree of economic importance which is grown around the world, including Saudi Arabia. Its fruit is nutritious and possesses medicinal benefits. Almond moth, is a serious date fruits pest in the field as well as in the storage and causes severe economic losses. In the given research, ultraviolet radiation type B (UV-B, 315 nm) harmful effects were evaluated against all developmental stages of C. cautella. One and 3-d-old eggs, 12 and 18-d-old larvae, 1-d and 6-d-old pupae, and 1-d-old adults, were exposed to UV-B for different intervals. Eggs were exposed for 0–30 min and 0% hatchability was achieved both for 1-d and 3-d-old eggs after 30 min. The larvae were exposed for 6–24 h, and after 24 h, mortality was 100 and 97% for 12 and 18-d-old larvae, respectively. Similarly, the pupae were exposed for 0–30 h, and 100% mortality was achieved after 30 h for 1-d-old pupae. Furthermore, none of the 6-d-old pupae emerged as an adult after 12 h of exposure. When adults were exposed for 1–4 d, no mortality was observed; however, UV-B reduced fecundity and hatchability in the treated adults. The susceptibility order was as follows: eggs > larvae > pupae > adults. Several uncharacteristic behaviors of C. cautella were noted, such as females depositing eggs openly on food items and containers, mature larvae exiting from food, larvae starting to wander for pupation, and pupation occurring typically outside the food. The application of UV-B could be an effective management strategy because all developmental stages of C. cautella were susceptible to UV-B that might be helpful to protect the dates from C. cautella infestation. Keywords: Cadra cautella, Dates, Ultraviolet radiation, Mortality, Survival ratios, Saudi Arabia

Postharvest almond moth (Cadra cautella Walker; Lepidoptera: Pyralidae) infestation is one of the primary challenges for production of dates, Phoenix dactylifera L. (Arecaceae) cv. ‘Khodari.’ This study was a simulation of early almond moth infestations in uncontrolled storage conditions. It aimed to investigate the effects of low level almond moth infestations on the population growth of the moth, the damage to the dates, bacterial and fungal contamination, and the nutritional value of the dates. One, 2, and 3 pairs of male and female moths were introduced into 250 g Khodari date samples. Noninfested dates were used as controls. Each treatment was performed in 10 replicates. The results showed a more than 25-fold increase in the almond moth population and significant damage to the dates. The moth population in the 2 pair treatment was the highest. Moth infestation also increased microbial contamination by more than 3-fold compared with noninfested dates. The treatment of the 3 pairs of moths significantly increased the bacterial load more than 20-fold when compared to the control. The fungal contamination in the 2 and 3 pair treatments were more than 5-fold higher than that of the control. In contrast, the moth pairs did not significantly affect the sugar, protein, fiber, ash, or water contents of dates. The results suggest that infestation by a single pair of almond moths at the initial stage postharvest causes significant damage and contamination in Khodari dates. Resumen La infestacion de la polilla de la almendra en poscosecha (Cadra cautella Walker; Lepidoptera: Pyralidae) es uno de los principales desafios en la produccion de los datiles Khodari. Este estudio fue una simulacion de infestaciones tempranas de la polilla de la almendra en condiciones de almacenamiento no controladas. Su objetivo era investigar los efectos de bajo niveles de infestacion de la polilla de la almendra sobre el crecimiento de la poblacion de la polilla, el dano a los datiles, la contaminacion por bacteria y hongo, y el valor nutricional de los datiles. Se introdujeron 1, 2, y 3 pares de polillas macho y hembra en muestras de datiles Khodari de 250 g. Se utilizaron datiles no infestadas como controles. Se realizo 10 repeticiones de cada tratamiento. Los resultados mostraron un aumento de mas de 25 veces en la poblacion de polillas de almendras y danos significativos en los datiles. La poblacion de polillas en el tratamiento de 2 pares fue la mas alta. La infestacion de polillas tambien aumento la contaminacion microbiana en mas de 3 veces en comparacion con los datiles no infestadas. El tratamiento de los 3 pares de polillas aumento significativamente en mas de 20 veces la carga bacteriana en comparacion con el control. La contaminacion por hongos en los tratamientos de 2 y 3 pares fue mas de 5 veces mayor que la del control. Por el contrario, los pares de polillas no afectaron significativamente el contenido de azucar, proteina, fibra, cenizas o agua de los datiles. Los resultados sugieren que la infestacion por un solo par de polillas de almendras en la etapa inicial posterior a la cosecha causa danos y contaminacion significativos en los datiles Khodari. Key Words: dates; almond moths; Cadra cautella; microbial contamination; nutrition View this article in BioOne

Biotic stress is one of the major environmental factors that affect the plant’s growth and life cycle. Plant pathogens are major constraints and severe threats to agricultural production in changing climate scenarios. The effects of climate variability on plant diseases and pathogens have been examined in various plant pathosystems. Climate change is predicted to affect the development of pathogens, their survival, vigor, sporulation, multiplicity, and host susceptibility that ultimately cause changes in the crop diseases. It also affects the inoculum dispersion and pathogenicity. These effects vary depending on pathosystems and geographic locations. Climate change not only affects optimal conditions of infection but also host specificity and infection mechanism in plants. Temperature, light, and humidity are the major factors that control the development and growth of diseases. So, climate change is an emerging challenge that is impacting and driving the plants and pathogens growth, disease development in a pathosystem. This overview is aimed to summarize the previous research, reviews, opinions, and recent trends in studying the effects of climate variability on pathogens and plants health. However, managing and predicting climate change impacts are complicated because of the interaction between the indirect effects and global climate change drivers. Similarly, uncertainty in plant disease development models in changing climate needs the diversification in management strategies. Protection of plants against diseases and pathogens is an essential direction for researchers to make the plants more resistant to pests and diseases. There is a need for further research in different areas under multiple climate-changing factors and scenarios using the disease modeling frameworks such as BIOMA and APSIM-DYMEX.

Maize flour was infested with fresh emerged Tribolium castaneum adults, and its nutritional composition was evaluated after 0, 45, and 90 days of the infestation. Furthermore, 99% carbon dioxide was applied to different developmental stages of T. castaneum for its management. There were six treatments and five replicates; for each replicate, maize flour (150 g) was taken in a 250-ml plastic jar container, insects were released in the flour, and jars were placed into the incubator at a temperature of 28 ± 1 °C, 60 ± 5% RH. Similarly, the application of 99% CO2 was done with four exposure times of 12, 24, 48, and 72 h, at 35 °C 65 ± 5% RH. Present results showed major fluctuations in the nutritive composition of maize flour. Increase in the moisture, fat, fiber, protein, and ash contents was directly proportional to the increase in infestation level and time, contrary to the depletion of carbohydrates and total weight loss. The results of CO2 treatment indicated that pupa was the most resilient stage as compared with larvae and adult stage. The observed susceptibility order was as follows: adult > larvae > pupae. The maximum mortality of adult, larval, and pupal stages was recorded after 24, 48, and 72 h of CO2 application, respectively. These findings might be helpful to develop an ecofriendly technique to manage this crucial pest.

Optimistic and sustainable supply of soil available nutrients to crop plants enhances productivity. Integrated nutrient management (INM) approach can improve soil fertility on long term basis. The present study was conducted to determine effects of INM on quantitative and qualitative characters of two Safflower (Carthamus tinctorius L.) cultivars “Thori-78 and Leed-00”. Five treatments using different composition of poultry litter, farm yard manure, nitrogen and phosphorous fertilizers with recommended dose as a control measure were replicated thrice in randomized complete design. The results of field trial depicted maximum plant height (174.6 cm), number of heads plant-1 (42.67), number of seeds head-1 (59.0), thousand seed weight (42.26 g), biological yield (3089 Kg·ha-1) and seed yield (455.2 Kg·ha-1) recorded from combined application of FYM @ 2 t·ha-1and Half (N-P) (soil application) (T5) in Genotype “Leed-00” which was statistically different from all other treatments. Thori-78 also showed increase in yield and yield components under the same treatment (T5) i.e.2 t·ha-1 FYM and Half (N-P).No effect of INM was found on fatty acid composition of safflower cultivars. The correlation coefficients illustrated positive and significant association of seed yield with plant height (0.89), number of heads pod-1 (0.86) and number of seeds head-1 (0.83) as a result of application of selected treatment. These results demonstrated the significance of INM in safflower yield improvement under rainfed conditions.

The development of cultivars resistant to tomato fruit borer, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), are very limited in Pakistan and other parts of the world because of the lack of good sources of resistance for breeding. Insect-resistant cultivars would be beneficial to decrease the indiscriminate use of pesticides on tomato crops. Seven wild tomato accessions, including Solanum galapagense Darwin & Peralta, Solanum pimpinellifolium L., Solanum cheesmaniae (Riley) Fosberg, and a susceptible check (Solanum lycopersicum L.) (all Solanaceae), were evaluated for resistance to tomato fruit borer based on oviposition preference and feeding in the choice and no-choice bioassays. In the oviposition preference test, S. cheesmaniae (VI037240) and S. galapagense (VI063174) recorded the lowest mean number of eggs, 4.40 and 7.00 per plant, respectively. The highest mortality of H. armigera larvae (90%) was recorded on S. pimpinellifolium (VI030462) compared to the susceptible check (15%). The lowest pupal weight (89.67 mg) resulted from S. galapagense (VI063174), but it was not significantly different from the S. pimpinellifolium and S. cheesmaniae accessions. Among all tested accessions, S. pimpinellifolium (VI030462) was found to be highly resistant to H. armigera based on larval mortality, pupal weight, and pupation percentage. These results can pave the way to enhance the resistance in cultivated tomato varieties to control this notorious fruit borer. Resumen El desarrollo de cultivares resistentes al barrenador de la fruta del tomate, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), es muy limitado en Pakistan y otras partes del mundo debido a la falta de buenas fuentes de variedades resistentes para el fitomejoramiento. Los cultivares resistentes a los insectos serian beneficiosos para disminuir el uso indiscriminado de pesticidas en los cultivos de tomate. Se evaluaron siete accesiones de tomates silvestres, incluyendo Solanum galapagense Darwin y Peralta, Solanum pimpinellifolium L., Solanum cheesmaniae (Riley) Fosberg y un control susceptible (Solanum lycopersicum L.) (todas Solanaceae), para determinar la resistencia al barrenador de la fruta del tomate en base de la preferencia de oviposicion y alimentacion en bioensayos de eleccion y no eleccion. En la prueba de preferencia de oviposicion, S. cheesmaniae (VI037240) y S. galapagense (VI063174) recibieron el numero promedio mas bajo de huevos, 4.40 y 7.00 por planta, respectivamente, en bioensayos de eleccion y de no eleccion. La mortalidad mas alta de larvas de H. armigera (90%) se registro en S. pimpinellifolium (VI030462) en comparacion con el control susceptible (15%). El peso pupal mas bajo (89,67 mg) resulto de S. galapagense (VI063174), pero no fue significativamente diferente de las accesiones de S. pimpinellifolium y S. cheesmaniae. Entre todas las accesiones analizadas, se encontro que S. pimpinellifolium (VI030462) es altamente resistente a H. armigera en funcion de la mortalidad de las larvas, el peso de las pupas y el porcentaje de pupacion. Estos resultados pueden ser un camino para mejorar la resistencia en las variedades de tomate cultivadas para controlar este notorio perforador de frutas. Key Words: tomato fruitworm; wild species; resistance; oviposition; antibiosis; mortality View this article in BioOne

A diatomaceous earth formulation enhanced with bitterbarkomycin (DEBBM) combined with Beauveria bassiana (Balsamo) Vuillemin was evaluated against lesser grain borer Rhyzopertha dominica F. (Coleoptera: Bostrychidae) under laboratory conditions. DEBBM was applied at the rates of 15 and 30 ppm alone as well as in combination with 6.69 ¥ 10

Evidence of fruit rot disease was observed in 12 bell pepper (Capsicum annuum L.) fields located in the Chakwal district (32°56′00″N, 72°51′30″E) of Pakistan during the period June 2016 to 2017. Disease incidence was estimated to be between 15 and 24%. Yield loss in affected fields was estimated as 11%. Symptoms of disease were seen as water-soaked, discolored necrotic lesions predominantly around the calyx. There were also symptoms of internal rot as seeds and the inner fruit surface were covered with white to light gray fungal growth. In the case of severe disease symptoms, fungal growth was also observed externally at the calyx end. The disease progressed as a soft decay with leakage. Diseased fruits were cut into 5-mm² pieces, surface disinfested with 1% NaOCl for 2 min, rinsed thrice with sterile distilled water, and incubated on potato dextrose agar (PDA) at 25 ± 2°C for 3 to 4 days under continuous fluorescent light. Eighteen isolates of similar morphology were purified using the hyphal tip technique. Colonies were fast growing, fluffy, white with pale cream to beige coloration on the reverse side of the Petri dish. Microconidia were hyaline, single celled to one septate, and 3.5 to 5.0 × 2.7 to 4.0 μm (mean = 4.0 × 3.8 μm). Mesoconidia were fusoid, usually three septate, and 9.8 to 17.5 × 3.0 to 4.5 μm (mean = 13.4 × 4.0 μm). Macroconidia were three to five septate, cylindrical, slightly curved, tapered at the apex, and 26.2 to 37.4 × 3.5 to 4.8 μm (mean = 32.5 × 4.2 μm). Based on morphological characteristics, the fungus was tentatively identified as Fusarium incarnatum (Leslie and Summerell 2006). DNA from two representative isolates, FICW7 and FICW16, was amplified with translation elongation factor (EF1-α) and β-tubulin genes using primers EF1/EF2 (O’Donnell et al. 1998) and Bt1a/Bt1b (Glass and Donaldson 1995), respectively. The obtained sequences for EF1-α (accession nos. MF977815 and MG770586) and β-tubulin (MF977818 and MG770587) were deposited in GenBank. The MegaBLAST and Fusarium ID database analysis revealed 99 to 100% homology to the Fusarium incarnatum-equiseti species complex, GenBank accession no. JF270273 (EF1-α), and AB587036 (β-tubulin) respectively. Pathogenicity tests of six isolates were conducted on three healthy bell pepper fruits per isolate, wound inoculated with a 20-μl drop of 10⁶ spores/ml. Three control fruits per isolate were inoculated with 20-μl droplets of sterile distilled water. Inoculated and control fruits were incubated in moist chambers at 25°C. After 3 to 5 days, white fluffy mycelial growth surrounded by water-soaked necrotic lesions appeared identical to the symptomatic fruits observed in the field/tunnel. No symptoms were observed on control fruits. The fungi isolated from the diseased fruits were morphologically similar to the original isolates on PDA. The pathogen was previously reported to cause the internal fruit rot disease of bell pepper in Trinidad (Ramdial et al. 2016). This is the first report of F. incarnatum (Desm.) Sacc. causing fruit rot on bell pepper in Pakistan. New strategies need to be developed for effective management of disease.