Allelopathic Effect of Peanut, Sunflower and Corn Crops on Germination and Growth of some Winter Weeds

The present study was carried out to study the effects of three summer crops water extracts (peanut, sunflower, maize) on germination and seedling growth of six winter weeds (Medicago polymorpha, L., Sonchus oleraceus, L., Lathyrus hirsutus, L., Phalaris minor, Anagallis arvensis, L., Rumex dentatus, L.) and two winter field crops (Beta vulgaris L. and Vicia faba L.) under laboratory conditions.Results revealed that Peanut water extract was recorded the highest mean inhibition values (31.25, 47.81, 89.58 and 74.22%) for L. hirsutus, A. arvensis, V. faba and B. vulgaris, respectively.On the other hand, the lowest mean inhibition values (97.92 and 85.16 %) were obtained from the maize water extract for V. faba and B. vulgaris, respectively.While, the highest inhibition values (27.50, 66.67, 59.83 %) were obtained from the interaction effect between Peanut extract with concentration 40% for A. arvensis, V. faba and B. vulgaris, the percentage inhibition of them were (69.44, 33.33, and 32.14 %), respectively.Peanut extract was recorded the highest mean inhibition values (6.12 and 7.06 cm) for shoot length of A. arvensis and B. vulgaris, respectively.On the other hand, maize extract was activated the growth of shoot V. faba values (17.26 cm).In addition, the highest inhibition percentages (80.22,79.61, 75.86, 65.64, 51.79, 25.39 and 15.66%) were obtained from 40% concentration for shoot length of M. polymorpha, R. dentatus, A. arvensis, S. oleraceus, P. minor, L. hirsutus and B. vulgaris, respectively, as compared with control treatment, in 2014.Moreover, the interaction effect between maize extract and concentration 20% for was activated growth of shoot length V. faba values (20.15 cm) the percentage inhibition for him (55.00 %).Peanut extract was recorded the highest mean inhibition values (1.38, 1.81, and 2.05 cm) for root length of S. oleraceus, P. minor and R. dentatus, respectively.On the other case, Sunflower extract was activated growth of shoot V. faba values (11.86 cm) while, peanut extract was activated the shoot growth of B. vulgaris values (13.58 cm).Also, 20% concentration was activated the root growth of B. vulgaris and V. faba (39.36 and 23.79 %) respectively.The interaction effect between peanut extract and concentration 20% was activated root growth of B. vulgaris values (15.85 cm), while, sun flower extract with concentration 20% was activated root growth of V. faba values (14.95 cm).Therefore, the water extracts of peanut, sunflower and maize showed the inhibitory effects on the seedlings of winter weeds.