Two field experiments were carried out during 1982/83 and 1983/84 seasons at Experimental Farm of National Research Centre at Shalakan, Kalubia Governorate, Egypt, to study the reversal effect of glyphosate induced phytotoxicity on growth and yield and its components of faba bean by the application of growth factors, i.e., growth regulators, amino acids and nutrient elements at different concentrations. A split plot design with four replications was used in both seasons. The obtained results indicated clearly that: Glyphosate at the two higher doses exhibited varying degrees of phytotoxic symptoms and reduced all the faba bean plant characters except the number of branches/plant. GA3 alone or in a mixture with cytokinin reversed the phytotoxic effect of the glyphosate herbicide on decreasing the plant height. Cytokinin at 4/1000, phenylalanine and tryptophan at both levels, as well as GA3 at 50 ppm, reversed the phytotoxic effect of the glyphosate herbicide on decreasing the dry weight/plant cytokinin at 4/1000, tryptophan at both concentrations, as well as, phenylalanine at 500 ppm, reversed the phytotoxic effect of the glyphosate herbicide on decreasing the number and dry weight of pods, seed yield per plant and per ha.

I. Abstract The influence of sowing dates (Oct. 21, Nov. 10, Nov. 30 and Dec. 21), weed control treatments using Brominal, Tribunil herbicides as compared to hand weeding and unweeded treatments on the yield performance of newly released spring wheat varieties (Sakha 8, Sakha 61 and Giza 157 was studied during 1980/81, 1981/82 and 1982/83 seasons. According to the combined analysis the results could be summarized as follows: Sowing date had significant effect on grain yield and some other characters such as plant height, days to heading and maturity, weight of grains per spike and 1000‐grain weight. Highest grain yield was obtained when wheat was sown during Nov. Dry weight of weeds was not significantly affected by sowing date. Differences between cultivars reached to the significant level in plant height, spike length, number of grains per spike and 1000‐grain weight. Weed control treatments had significant effect on most studied traits. Grain yield was nearly the same when Tribunil (3.5 kg/ha), Brominal (2.4 1/ha) or hand weeding was used. Grain yield of unweed treatment decreased by 10.9%, 10.9% and 9.8% compared to the former treatments, respectively. Data showed that Tribunil was more effective on both grassy and broad leaved weeds, however, Brominal was effective only on broad leaved.

Two field experiments were carried out during 1982/83 and 1983/84 seasons at Experimental Farm of National Research Centre at Shalakan, Kalubia Governorate, Egypt, to study the effects of supplemental growth factors on the reversal of glyphosate-induced inhibition in photosynthetic pigments and protein in faba beans. A split plot design with four replications was used in both seasons. Glyphosate at 0,312 and 468 g.a.i./ha as well as the untreated treatment, arranged at random in main plots while, the growth factors, i.e., growth regulators, amino acids and nutrient elements at different concentrations distributed randomly in the sub plots. The results could be summarized as follows: 1. Glyphosate decreased chlorophyll a, b and carotenoides content and the total pigments content in the leaves of faba bean plants, as well as, the protein content of seeds and protein yield per hectare. 2. The treatments of phenylalanine at 500 ppm, urea at 1 %, cytolinin at 4/1000 and tryptophan at 500 ppm, reversed the glyphosate-induced-phytotoxicity on decreasing the chlorophyll a, b content and total pigments content in faba bean leaves. The same treatments, as well as, zinc sulfate at 1 %, reversed the glyphosate-induced-phytotoxicity on decreasing the carotenoids content in faba bean leaves. 3. The treatment of GA3 at 100 ppm gave the highest percentage of crude protein in seeds, while the lowest value was obtained from cytokinin at 4/1000, in both seasons. 4. The treatments of cytokinin at 4/1000, phenylalanine at 500 ppm and tryptophan at both levels, reversed the glyphosate-induced-phytotoxicity on decreasing the protein yield per h.

The effect of butachlar, oxadaiason, pendimethalin, avirosan, bentazon and their combinations for control of barnyard grass and umbrella sedge in rice (Oryza sativa L.) was studied in two field experiments at the Experimental Farm of the National Research Centre at Shalakan, Kalubia Governorate; Egypt, during 1982 and 1983. The differences in response among weeds and rice to post-emergence herbicides and their combinations were very variable. The combination herbicides: pendimethalin at 0.83 kg + bentazon at 1.44 kg/feddan* butachlor at 1.0 kg + pendimethalin at 0.83 kg/feddan, oxadiaton at 0.5 kg + pendimethalin at 0.83 kg/feddan and avirosan at 0.5 kg + bentazon at 1.44 kg were very effective against Echinochloa crus-galli. Oxadiazon at 0.5 kg and avirosan at 0.5 kg as well as the combination of Butachlor at 1.0 kg + oxadiazon at 0.5 kg or Avirosan at 0.5 kg and avirosan at 0.5 kg + bentazon at 1.44 kg/ feddan gave the best weed control against Cyperus difformis. All combination herbicides as well as the hand weeded treatment gave superior rice yields over those of the single herbicidal treatments.