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1985, RNA and protein metabolism during adventitious root formation in stem cuttings of Phaseolus aureus. -Physiol, Plant, 64: 53-59,Indole-3-butyrie acid (IBA, lO-'Af), spermine (7 X W^M) and vitamin Dj (6,3 X W^M), all of which enhance rooting in mung bean cuttings (Phaseolus aureus Roxb, cv, Berkin), influence RNA metabolism. Total and poly (A)''^-RNA synthesis within the hypocotyl is inhibited by each of these chemicals within 24 h. These changes precede induced cell division and are therefore associated with the so-called induetive period of regeneration dtiring which some cells in the hypocotyl undergo dedifferentiation. However, following subsequent transfer of cuttings to borate, which is an essential prerequisite for development of root primordia in these cuttings, RNA synthesis is enhanced by pretreatments with IBA, spermine or vitamin D,, Ftirthermore, IBA inhibits synthesis and turnover of protein within the hypocotyl.Additional key words -Indole-3-butyric acid, mung bean, spermine, stem-cuttings, vitamin Dj, B. C. Jarvis (reprint requests), S. Yasmin artd M. T. Coieman,

Summary An interaction between auxin and boron in the rooting response of stern cuttings of Phaseolus aureus Roxb. is described. The optimum response to one variable is dependent upon the value of the other and vice versa. Whereas the number of roots per cutting which develop is diminished when high concentrations of boron are supplied immediately after treatment of cuttings with auxin, subsequent root growth is enhanced by such treatment. These results are discussed with respect to the possible role of boron in controlling endogenous auxin concentration via an effect on IAA oxidase.

Salt tolerance and cation interaction in alkali sacaton (Sporobolus airoides Torr.) was studied during the germination stage. Germination was inhibited at a concentration of 275 meq/liter of sodium chloride. Mannitol and other salts at iso-osmotic pressure restricted germination in the following decreasing order: MgCl,, KCl, CaCI,, NaCI, and mannitol. Inhibitory effects of mag nesium on germination were partially counteracted by calcium and sodium. Greater recovery in germination was noted by addition of calcium than sodium in seeds previously treated with a high concentration of magnesium chloride. The role of sodium and calcium in counteracting magnesium effects has been discussed. It is also concluded that specific effects of salts are more important than osmotic effects on the seed germination of this species. Cultivation of salt tolerant forage plants which can grow under natural rainfall is profitable where land is highly saline and adequate water for leaching down the salt is not available (Malcolm, 1969). This approach is one utilization rather than reclamation of saline soils. Vast areas of land with low rainfall and high salinity are found throughout West Pakistan. Neither crops nor good quality grasses can grow on such lands. In the southern region of West Pakistan this problem is more acute because of fodder shortage. In order to make the best use of such land, a search is being made for exotic species which can thrive and produce fodder under our local conditions. Alkali sacaton (Spo~obolus

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