Trichogramma chilonis, an effective egg parasitoid for control of white stem borer Scirpophaga innotata (Walker), (Lepidoptera: Pyralidae) in rice

Rice an important staple food crop of the world, which is attacked by the various insect pests, among them the stem borers are the most destructive pests, distributed in all rice growing areas of the world and cause the severe losses. This research investigated the efficacy of the parasitoid Trichogramma chilonis (Ishii) to control the white stem borer (Scirpophaga innotata) in rice. In this respect the field studies were conducted in lower Sindh, Pakistan for the year, Kharif - 2017 and 2018. Trichogramma egg parasitoid over 230 species are reported to have been remained in biological control of insect pests of over 200 insect species belonging to 70 different families, mainly the order Lepidoptera, Hemiptera, Orthroptera and Thysnoptera, in order to manage the white stem borer of rice the Trichogramma chilonis (Ishii) was used as a bio-control agent. The Studies revealed that T. chilonis proved an effective biocontrol strategy against white stem borer of rice. The result of this study could be useful in an integrated pest management program for the management of white stem borer of rice the Trichogramma chilonis.            

Performance of pheromone and light traps in monitoring and management of tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae)

Tuta absoluta is an invasive, oligophagous pest that has been recently reported from Pakistan. Although originated from South America, it has now introduced and spread in almost all the tomato growing areas of the globe including Pakistan. Therefore, delta type pheromone traps containing synthetic 0.8 mg pheromone along with various colored light traps i.e., red, blue, golden, white, and green were evaluated for the monitoring and management of T. absoluta. Weekly observations were taken for the mean capture of T. absoluta moths in traps along with mean infestation percentage on leaves, stems and fruits of tomato. Results indicated that all the traps were found effective to attract T. absoluta moths, but they vary in their effectiveness to capture moths. Pheromone traps capture only males, whereas light traps attracted both the sexes. Significantly the highest number of males were captured in female synthesized pheromone traps, followed by golden color light traps, whereas red color light traps capture least number of males. Males captured in blue, white, and green color light traps were not significantly different from each other. Significantly the highest number of females were captured in golden color light traps, followed by blue color trap, whereas females capture in white and green color light traps were not significantly different from each other. The least number of females were captured in red color light traps. The tomatoes grown in golden color light and pheromone traps significantly suffered the lowest infestation, followed by blue, white, and green color light traps, whereas maximum damage was observed in red color light trap treatment. Only temperature showed a significant but very weak influence on the performance of various traps to attract T. absoluta moths. Therefore, studies should be undertaken to evaluate various combination of light traps with pheromone to maximize the capture T. absoluta moths, that could not only help in its early monitoring and detection but could lead to its mass destruction

In vitro bioassays of some plant extracts against Banana anthracnose caused by Colletotrichum musae

Anthracnose of banana caused by Colletotrichum musae is an invasive disease, which is difficult to control in the export process. Plant extracts used to control plant diseases are gradually becoming substitutes for traditional fungicides because they are safe for the human body and environmentally friendly. The study was conducted to record the prevalence of banana anthracnose in two locations and to determine the best medium for the growth of C. musae and botanical extracts for managing the fungus under in-vitro conditions. Six media viz., Ripen banana peels media (RBPM), Unripen banana peels media (URBPM), Ripen banana flash fruit media (RBFFM), Unripen banana flash fruit media (URBFFM), Banana leaf media (BLM) and Potato dextrose agar media (PDA), four botanical extracts including Garlic (GC), Mint (MT), Eucalyptus (EC) and Neem seed (NS) at 2, 4 and 6% concentrations were tested against the fungus and the control (CL) remain untreated. Potato dextrose agar media (PDA) was used as a standard semi-synthetic growth media. The prevailing frequency of the disease was high in the investigation area. The maximum linear mycelial growth of the C. musae was recorded on PDA (85 mm) followed by URBFFM (40 mm), RBFFM (26 mm) whereas the lowest mycelial growth was recorded on BLM (20 mm) and URBPM (8 mm). In-vitro experiments showed that PDA was the best medium for the mycelial growth of C. musae. Moreover, tested botanical extracts showed high variation in reducing the colony growth of the fungus. EC was found most effective in reducing the colony growth of the fungus followed by NS, GC and MT. These results suggest that all the botanical extracts may be potentially useful for controlling anthracnose of bananas, EC extract can be effectively used for the field experiment