Volume 46, Issue 2
August 1957, pages 75-148
pp 75-95 August 1957
pp 96-109 August 1957
pp 110-125 August 1957
A brief account is given about the distribution and cycle of phosphates in the sea in the temperate and tropical waters, the recent investigations in the Indian waters being discussed in some detail. The data on the total phosphorus content of the waters along the Indian coast show that the values for total P are generally more than 3 times and sometimes nearly 40 times the values given by Harvey for the waters of Western English Channel. A hypothesis is presented which would explain the observed cycles of the phosphate-phytoplankton relationships on the Indian coastal waters to some extent, particularly in the Malabar waters. While the monsoon high values are caused by the release of locked-up phosphates in the bottom, it is suggested that a continuous source of replenishment is essentially to be presumed for the long duration of the simultaneous maxima of both phosphates and phytoplankton during the monsoon. Three such sources of replenishment are indicated. The post-monsoon ‘erratic’ fluctuations in phosphates and phytoplankton can be explained as due to a somewhat cyclical repetition of the usual phenomena of utilization, regeneration and phytoplankton production, until low levels of both phytoplankton and phosphates are established during the subsequent pre-monsoon months.
pp 126-130 August 1957
It might, therefore, be stated that the rust onErianthus munja was none other thanPuccinia kuehnii found onE. arundinaceus. Its pathogenicity on the former, however, was not found to be as great as on the latter.
pp 131-137 August 1957
Culture filtrates of twenty-one species ofFusarium were tested for their action on cotton tissue respiration. Filtrates ofF. buharicum, F. bulbigenum var.lycopersici, F. culmorum, F. dimerum, F. javanicum, F. lateritium, F. lini, F. moniliforme, F. orthoceras, F. oxysporum var.nicotianae, F. sambucinum, F. solani, andF. udum elicited high increases in tissue respiration over the control, whereas that ofF. caucasicum, F. equiseti, F. semitectum andF. sporotrichioides inhibited the respiratory rate.F. lateritium, F. oxysporum andF. vasinfectum caused only slight stimulation in tissue respiration.
Various organic acids, growth substances, amino acids and vitamins present in the culture filtrate when tested individually were found to increase respiratory rate and these probably played a part in stimulating respiration inFusarium infected tissue.
pp 138-148 August 1957
Deficiency of vitamin B6 in rats had no effect on serine decarboxylation, though, serine deamination and glycine to serine synthesis were reduced.