A field experiment was conducted with paddy (Oryza sativa L.) irrigated with different concentrations (Control, 2.5,5,10,25,50,75, 100 and 200 mg/l) of chromium. The changes in growth, yield, nutrient content and chromium accumulation in the paddy are reported. The growth of shoot, root, total leaf area, fresh weight, dry weight and yield of the paddy gradually decreased with increasing Cr concentration. Similarly, the uptake of macronutrients (N, P, K) and micronutrients (Mn, Cu, Zn, Fe) were also gradually decreased. However, the chromium accumulation gradually increased with the increasing concentrations of chromium. Among the aquatic plants tested, Eicchornia crassipes showed better performance in accumulating higher amount of chromium. Similarly, certain grasses and weeds such as Cyperus rotundus, Cyperus kylinga, Marselia quadrifolia and Ludwigia parvifloria were used for the phytoremediation of chromium polluted soil. Among them, Cyperus rotundus accumulated higher amount of chromium than the other plants tested.

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Biofertilizers are becoming increasingly popular in many countries and for many crops, but very few studies on their effect on growth in seedling stage have been conducted in rice. The experiments were conducted under laboratory conditions due to organic manure, fertilizers and bio fertilizers were observed in all experiments. The treatments such as organic manure, chemical fertilizers and Biofertilizers alone and in combination were applied. The growth parameters viz. germination percentage, root length, shoot length, fresh weight and dry weight were measured. Similarly the pigment contents such as chlorophyll-a, b, total chlorophyll and carotenoid were also measured at seventh day after sowing. All the parameters were higher in combined application of Biofertilizers than in single application and other treatments including control.

Heavy metals are the metals having a density at least five times more than that of water. They are normally regarded as ones having an atomic number of 22-92.The effects of different concentration (5, 10, 25, 50 and 100 mg/l) of arsenic and manganese on germination, root growth and cell division in root tips of green gram (Vigna radiata.L) were studied. The inhibition of germination and root growth was noticed at higher concentrations of Arsenic and manganese. Arsenic had more toxic effect than manganese on the root tip cells of greengram during mitosis. Chromosome stickness implied the high toxicity of arsenic and manganese. The results also indicated that the germination percentage and root length was gradually decreased with the increasing concentration of both heavy metals.Keywords: Arsenic, manganese, cell division, growth. ‫ﻓﻲ‬ ‫اﻟﺨﻼﻳﺎ‬ ‫واﻧﻘﺴﺎم‬ ‫اﻟﺠﺬور‬ ‫ﻧﻤﻮ‬ ‫ﻋﻠﻰ‬ ‫واﻟﻤﻨﻐﻨﻴﺰ‬ ‫اﻟﺰرﻧﻴﺦ‬ ‫أﺛﺮ‬ ‫ﻟﻨﺒﺎت‬ ‫اﻟﻘﻤﻴﺔ‬ ‫اﻟﺠﺬور‬ ‫ﺧﻼﻳﺎ‬(Vigna radiata L.) ‫اﻟﺨﻀﺮاء‬ ‫ﻏﺮام‬

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