Interference of three weed extracts on uptake of nutrient in three different varieties of paddy through radio tracer techniques.

Interference of three dominant weed extracts viz., Ageratum conyzoides L., Melilotus indica All. and Parthenium hysterophorus L. were examined on seed germination, seedling growth, and nutrient uptake (32P and 65Zn) in three different varieties (PD-10, PD-12 and PB) of paddy (Oryza sativa L.). Among the three different varieties irrespective of weed extracts, PD-10 and PD-12 were resistant and PB was susceptible in terms of seed germination, radicle length and plumule dry weight; and PD-12 and PB were resistant and susceptible, respectively, in terms of plumule length and total seedling dry weight. A. conyzoides caused maximum reduction in seed germination and M. indica in seedling growth in different varieties of paddy. The weed extracts interfered in uptake of both 32P and 65Zn and there was a gradual decrease in uptake of both nutrients with increasing concentration of extracts in both root and shoot. The uptake of 32P and 65Zn was more inhibitory with the extracts of A. conyzoides and M. indica, respectively in different varieties. The inhibition in seed germination, seedling growth and nutrient uptake may be due to the presence of phenolics and other secondary metabolities. The phenolics such as gallic, vanillic, protocatechuic and p-hydroxybenzoic acids were identified from these weed extracts.

Great particles (32P) chromic phosphate for treatment of solid tumors

With the purpose studying the effectivity of an intratumoral single dose of chromic [(32)P] phosphate with great particles for the treatment of solid tumors, studies of biolimination, biodistribution and therapeutic action were carried out. Only for comparative purpose, similar studies were undertaken using a solution of sodium [(32)P] orthophosphategelatine. The results show that when sodium [(32)P] orthophosphategelatine is used, the percentage of total elimination is (85.90+8,70) per cent with a higler percentage in urine (64.50+13.70) per cent than in faeces (21.40+4.50) per cent. In biodistribution studies, the greater percentage is found in bone (15.54+2.21) per cent while only a (2.51+0.39) per cent remains in the tumor. When great particles chromic [(32)P] phosphate was intratumorally injected, we determined that the total elimination is equal (36.28+6.27) per cent, finding a higler amount in faeces (29.44+5.26) per cent than in urine (6.84+2.21) per cent. Biodistribution studies demonstrated that (49.82+5.41) per cent remains in the tumor and (9.63+4.89) per cent of the injected activity is found in the liver. On the other hand, when therapeutic action was evoluted, we observed that the percentage of tumor regression (P.T.R) is 52.0 per cent for the tumors injected with chromic [(32)P] phosphate and 0.0 per cent for those injected with sodium [(32)P] orthophosphate-gelatine. These results show that the great particles colloid of chromic [(32)P] phosphate is not safe enough for the tratment of solid tumors, since it is mobilezed from the injection point, delivering a high dose to the whole organism.