Fruit flies are responsible for causing significant yield losses, dropping the values and creating hindrances in the exports of agricultural produces (Sarwar, 2015). Fruit flies are transported across borders with international trade of fruits and vegetables and hence are regarded as major quarantine pests (Permalloo, 1998; Peck and McQuate, 2004). The damages inflicted by the fruit flies lead to reduced farm produce and hence to limited exports Abstract | The tephritid fruit flies are the major pests of horticultural crops across the globe. In Pakistan, two fruit fly species, Bactrocera zonata (Saunders) and B. dorsalis (Hendel) cause severe qualitative and quantitative damages to various fruits. The present study was executed to record the population dynamics of these fruit fly species in guava and mango orchards with respect to meteorological factors using methyl eugenol-baited traps. The results revealed that population of both the species highly fluctuated round the year. B. zonata appeared to be the most abundant species both in mango and guava orchards as compared to B. dorsalis. The highest mean number of B. zonata (3690.57 flies/trap) was captured in August 2018 in guava orchard. From October, 2018 onward up to February 2019, population of B. zonata tended to decline with the lowest catches (122.5 and 152.8 flies/trap, respectively) in January and February, 2019. In mango orchard, peak population of B. zonata (4062.8 flies/trap) was recorded in May, 2019. Abundance of B. dorsalis in guava orchard reached to its peak (394.625 flies/trap) in August, 2018. However, in mango orchard, an increasing trend in population was observed from April onward with the highest catches of 521.4 flies/trap in June. The correlation matrix revealed a significantly positive relation among the incidence of B. zonata and minimum and maximum temperatures and sunshine hours whereas relative humidity (R.H.) and rainfall were found to have a negative correlation with B. zonata abundance. Correlation analysis of B. dorsalis catches with respect to meteorological data revealed a significantly positive correlation of monthly captured flies with all the climatic factors such as maximum temperature, minimum temperature, R.H. and sunshine duration except the mean monthly rainfall.

Tobacco (Nicotiana tabacum) is an herbaceous plant originating from South America and processed into cigarettes for consumption. Polyphenols are considered vital components of tobacco in view of their contribution to antioxidant properties. This study aimed to determine the phenolic compounds in different tobacco varieties by applying cold extraction with methanol and distilled water. The extracts were screened for phenolic compound diversity and distribution as well as their antioxidant potential in different tobacco varieties. The results showed that the methanolic extract of tobacco SP-28 exhibited the highest value in the total phenolic content (24.82 ± 0.07 mg GAE/gd.w.) and total flavonoid content (4.42 ± 0.01 mg QE/gd.w.), while the water extract of tobacco SN-2 exhibited the highest value in the total condensed tannin (1.12 ± 0.03 mg CE/gd.w.). The radical scavenging capacities of tobacco SP-28 were relatively high in DPPH (18.20 ± 0.01 mg AAE/gd.w.) and FRAP (3.02 ± 0.10 mg AAE/gd.w.), whereas the ABTS value was the highest in tobacco SN-2 (37.25 ± 0.03 mg AAE/gd.w.), and the total antioxidant capacity was the highest in tobacco SN-1 (7.43 ± 0.18 mg AAE/gd.w.). LC-ESI-QTOF-MS/MS identified a total of 49 phenolic compounds, including phenolic acids (14), flavonoids (30), and other polyphenols (5) in four different tobacco varieties. Tobacco SP-28 showed the highest number of phenolic compounds, especially enriched in flavones. Our study highlights the antioxidant potential of tobacco extracts and reveals the phenolic distribution among different tobacco varieties that could support tobacco utilization in different pharmaceutical industries.

The variegated lady beetle, Hippodamia variegata (Goeze, 1777) is widely distributed in different agroecosystems of Turkey. Cannibalism, intraspecific predation, where individuals of the same species feed upon each other, is a common phenomenon in most aphidophagous coccinellids including H. variegata. We investigated the cannibalistic behavior of various growth stages of H. variegata in the presence and absence of Acyrthosiphon pisum Harris, 1776 under laboratory conditions. The results for cannibalism of eggs and larvae by adults revealed that eggs and younger larvae were more vulnerable to cannibalism. Notably, egg cannibalism by adults was found to be higher even at high prey abundance. Whereas, larval cannibalism was found significantly lower. Cannibalism of eggs by larvae and within the larvae showed that older larvae consumed significantly higher number of eggs and younger larvae in the absence of A. pisum indicating that cannibalism was mainly influenced by scarcity of prey. However, all the larval instars, especially 4 th and 3 rd instars, also consumed a substantial number of eggs even in the presence of prey. Cannibalism within the same stage/age larvae showed a successive increase with the successive larval stage showing minimum cannibalism by 1 st instar larvae and maximum by 4 th instar larvae. The study found that scarcity of prey leads to cannibalism in H. variegata and that egg cannibalism occurs even at high prey densities.

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