Muhammad Dildar Gogi

Host-plant-preference and Mortality Analysis of Phenacoccus solenopsis in Association with Biochemical Traits of Different Plant Species

Dietary requirement and fitness of phytophagous insect pest depend upon the nutrient chemistry of host plant. The present research was carried out to investigate the association of host-plant-preference and mortality of Phenacoccus solenopsis first instar influenced by chemical characteristics of plant species. The experiment was carried out at (25 + 5oC and 60 + 5% RH) in Integrated Pest Management Laboratory, University of Agriculture, Faisalabad, Pakistan during 2012. First instar exhibited maximum (attractiveness index = 0.75) toward Gossypium hirsutum followed by Trianthema portulacastrum (0.34) as compared Hibiscus rosa-chinensis (1.00) kept as standard. Mortality percentage of 1 instar of CMB among 25 tested plant species ranged from 10% in cotton to 80% in Conyza bonariensis. Cluster analysis for biochemical traits showed that cluster-1 comprised of Lantana camara, H. rosa-sinensis, Helianthus annuus, Parthenium hysterophorus, Withania somnifera, Euphorbia prostrate, Portulaca oleracea, Solamum melongena, T. portulacastrum, G. hirsutum, Abelmoschus esculentus and Capsicum frutescens that had maximum attractiveness and less mortality. Cluster-2 Convolvulus arvensis, Eclipta prostrate, Amaranthus spinosus, Clerodendron inerme and Tribulus terrestris had medium whereas cluster-3 Launea nudicaulis, Chinopodium morale, C. album, Achyranthes aspera, C. bonariensis and Digera arvensis least attractiveness index but highest mortality. Principal component analysis (PCA) depicted that first three PCs expressed 83% of the total variability. Mortality of pest was negatively correlated with nitrogen and but positively with potassium, phosphorus, sodium, reducing sugar and total sugar. In conclusion, chemical contents affected attractiveness index and mortality of P. solenopsis; however there is need to explore allelochemicals imparting resistance against P. solenopsis.

Insect-Pests in Dryland Agriculture and their Integrated Management

More than 700 million people reside in arid and semi-arid regions, which comprise about 40 % of the world’s land with about 60 % of this area in developing countries. The United Nations estimated that the world population would be 9.7 billion by 2050. Therefore, enhancing crop productivity in agroecosystems especially in drylands is essential to feed the future population. Insects are dominant animals on Earth with about one million described species. More than a thousand species of insect pests adversely affect food crops in dryland agroecosystems. They can cause between 50 and 100 % of pre- and post-harvest losses. The control of insect pests in dryland agroecosystems is challenging due to adaptations (morphological, physiological, behavioral and ecological) to survive in those conditions. Therefore, a sustainable management approach is necessary for sustainable plant protection and food security in dryland cropping systems. If applied efficiently and strategically, integrated pest management has the potential to solve pest problems while minimizing risks to people and the environment. The main components of integrated pest management for sustainable agriculture and food security in dryland agriculture are the identification of pest problems and their abiotic/biotic limiting factors, establishment of economic decision levels of pest species, efficient and advanced pest monitoring and forecasting systems, biotechnologically-based host plant resistance approaches, revolutionary crop rotation systems, ecological engineering of dryland landscape systems, introduction, manipulation and conservation of biological control, adoption of precision production, protection technologies, and the implementation of biorational and other soft, ecofriendly innovative approaches. In dryland cropping systems, multidimensional and multidisciplinary research integrating simple and inexpensive scientific technologies should be executed to tackle/solve prevailing and emerging plant production and protection issues on a sustainable basis. A better understanding of the processes and appropriate insect pest management implementation to reduce crop yield losses will provide long-term sustainable production systems in dryland areas.