WEED DIVERSITY IN WHEAT FIELDS OF UPPER INDUS PLAINS IN PUNJAB, PAKISTAN

Transact walks were carried out through randomly selected wheat fields of Upper Indus Plains, Punjab, Pakistan. Dominant weed in each wheat field was found different although general weed flora did not show much variability and in total 105 weed species belonging to 33 families were enlisted in these fields. Among these, sixty two species of 25 families were recorded in non- saline irrigated, seventy two of 25 families in riverian non-irrigated and fifty eight of 22 families in partially saline irrigated wheat fields. Anagallis arvensis L., Avena fatua L. Chenopodium album L., Convolvulus arvensis L., Coronopus didymus (L.) Smith, Cynodon dactylon (L.) Pers., Medicago polymorpha L., Melilotus indica (L.) All., Phalaris minor Retz. and Rumex dentatus L. were recorded from all fields. Some weeds like Arundo donax L., Equisetum debile L., Lotus corniculata L., Persicaria barbata (L.) Hara., Phragmites karka Trin ex Steud., Saccharum bengalense Retz., Saccharum spontaneum L., Tamarix dioca Roxb., Typha angustata Bory Chaub. and Veronica polita Fries. were found dominant in riverian wheat fields, while Alhagi maurorum Medic., Conyza ambigua L., Desmostachya bipinnata (L.) Stapf. and Erythrea ramosissima (Vill.) Pers. were the inhabitants of both partially saline and riverians wheat fields. The weeds like Atriplex schugnanica Ilgin, Cotula hemispherica (Roxb.) Wall., Cynoglossum micranthum Desf., Goldbachia laevigata (M. Bieb.) D.C., Heliotropium europaeum L., Heliotropium undulatum Vahl., Potentilla supina L., Salsola imbricata Forssk, Spergula arvensis L., Spergularia marina (L.) Grisch and Sueda fructicosa Forssk. were commonly found in partially saline soils and hence could be declared as more salt tolerant weed species as compared to other weeds. The early growing weeds like Asphodelus tenuifolius Cav. was not recorded during recent surveys except only at one site in village Mohlanwal. The ecological and management status of wheat fields could be responsible for weed diversity.