Laboratory and pot experiments were conducted at the Department of Weed Science, The University of Agriculture
Peshawar, Pakistan during fall 2011 and repeated in 2012. Allelopathic plants were used against wheat and associated
weeds. Allelopathic plants showed significant activity against three selected species - Triticum aestivum, Avena fatua
and Rumex crispus. Aqueous extracts of Parthenium hysterophorus and Datura alba showed significant effect against
weeds of Triticum aestivum although aqueous extract of Phragmites australis possessed moderate activity. It was noted
that aqueous extract of Oryza sativa and control were comparable for all parameters studied. Aqueous extract of P.
hysterophorus and D. alba decreased seed germination, shoot length, fresh and dry biomass as compared to the rest
of the treatments. The degree of toxicity of different treatments can be placed in the following order of inhibition: P.
hysterophorus > D. alba > P. australis > O. sativa ≥ control. The present studies showed that the plants used contain water
soluble allelochemicals that retard or inhibit the germination, growth and biomass of other species. These experiments
suggests that P. hysterophorus, D. alba and P. australis extracts may have negative effect on major weeds like A. fatua
and R. crispus. Thus there is a possibility of using these plant extracts for weed management. However, more extensive
studies is required to identify the allelopathins responsible for inhibitory effects on seed germination and plant growth.
Zinc (Zn) deficient soil prevails throughout the world and it has become the bottleneck in achieving production potential
and quality of crops. The negligible use of micronutrients along with irregular use of macronutrients is practised for
fodder production in Pakistan. Varying levels of zinc (0, 5, 10 and 15 kg ha-1) and nitrogen (0, 60, 120 and 180 kg ha-1)
were evaluated for their effect on yield, quality and zinc uptake on fodder sorghum (variety Hegari) in a field experiment
for two consecutive years (2014 and 2015). Data were analysed by using Fishers’ analysis of variance (at p<0.05) and
response surface methodology (RSM). Correlation between different parameters was also studied. Application of zinc
and nitrogen improved the plant height, leaf area plant-1, green fodder yield, dry matter yield, crude protein percentage
and zinc content of plant but decreased the neutral detergent fiber, acid detergent fiber and ash percentage. Values for
different parameters recorded at second and third levels of zinc and nitrogen were remained at par with each other.
Application of 10 kg ha-1 zinc and 120 kg ha-1 nitrogen showed an average increase of 7.3 and 18.6% in green fodder
yield while 12.1 and 15.8% in dry matter yield, respectively. Similarly 6.1 and 7.5% increase in crude protein was noted
over control. Correlation between NDF and ADF was negative with rest of the studied parameters. In conclusion, Zn2
and
N2
gave the best results in term of yield and quality of fodder sorghum.