Allelopathic effect of weed species extracts on germination, growth and biochemical aspects in different varieties of wheat (Triticum aestivum L.)

The effect of weed extracts of Ageratum conyzoides L., Chenopodium album L., Cynodon dactylon (L.) Pers., and Parthenium hysterophorus L. were examined on the seed germination, seedling growth, chlorophyll, proline and total protein content in wheat (Triticum aestivum L.) varieties (PBW-154, PBW-343, PBW-373, PBW-443, PBW-502, RR-21, UP-262, UP-1109, UP-2382 and UP-2425). Weed extracts decreased germination (%) at the end of experiment (after 8 days) in all wheat varieties except in PBW-502, RR-21, UP-262, UP-1109 and UP-2382. The seedling growth (both length and dry weight) was reduced, along with chl-a and chl-b content, and proline (a stress amino acid) content increased in all the varieties compared to control. Among the four weed extracts, the inhibitory effect on different varieties of wheat on these parameters followed the order: P. hysterophorus > A. conyzoides > C. album and > C. dactylon. However, the total protein content was either increased or decreased in all the varieties compared to control. Among the varieties, RR-21, UP-2382 and UP-2425 were resistant; PBW-343, PBW-373, PBW-502 and UP-1109 were susceptible with different weed extracts.