V ARIOUS crop species exhibit widely differing degrees of salt tolerance at early growth stages. Ayers and Hayward (2) reported that 'California Mariout' barley germinated fairly well at high osmotic pressures in soils salinized with sodium chloride. Additionally, they found that sugar beet germinated poorly, and kidney bean not at all, at moderate osmotic pressures. Varieties within a species also may exhibit wide variation in ability to tolerate saline conditions at early stages of growth. Among 30 worldwide varieties of barley, Ayers (1) found that the tolerance limits for a 50% reduction in germination ranged from 12 atmospheres for 'Arivat' to 20 atmospheres for California Mariout. Uhvits (7) found that alfalfa seeds absorbed water more slowly but accumulated more chloride from a sodium chloride solution as the osmotic pressure of the solution increased. She showed that, in the greenhouse, the result of the physico-chemical effect of salt was a reduced rate of emergence of seedlings, depending on the concentration. A respiration response to salinity has been reported by at least two groups of workers. Sarin and Rao (6) studied the influence of sodium sulfate on the respiration of gram and wheat during germination. They reported that sodium sulfate depressed respiratory activity in gram more than in wheat. Henckel and Strogonov (5) considered the effects of specific ions on the metabolism of several crop species and observed that the chloride ion decreased the rate of respiration. To elucidate further the physiology of salt tolerance during the critical initial growth phase, we investigated the respiratory response to several salts as related to the germination of three forage species with widely differing abilities to tolerate salinity.

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Antifungal activity of the extracts of whole red velvet mite, skin and fresh haemolymph was evaluated. It was very interesting to observe that all the above three components registered a good antifungal activity. Of the three products of mites tested, the fresh haemolymph registered the maximum antifungal activity. Next to the haemolymph, the alcohol extracts of the skin exhibited a high antifungal activity. A dose dependent variation was observed in the antifungal activity. The extracts of haemolymph at a dose level of 200 mg/disc showed the highest inhibitory activity.

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