Increasing salinity levels (0.2 to 0.6%) significantly decreases leaf dry weight of all the species (Table 3). However, the most tolerant species was Aegilops tauschii (V₃) having 84.8% growth at the highest salinity level (0.6%) when compared with control. Similarly the most sensitive one was Triticum dicoccum (V₄) having 40.4% reduction at the maximum salinity level. It was also observed that degree of reduction increased proportionally with the increasing concentration of salts. Inhibition of growth by salinity is due to the inhibitory effect of ions. As a result of this inhibition carbo-hydrates and nitrogenous substances are not fully utilized (STROGONOV 1962).

However, salinity also damages the mechanism of control of intracellular orthophosphate (Pi) concentration (Mass and Hoffman, 1977) and could be expected to adversely affect growth.

The decrease in growth of different crops with increasing salinity have been reported (ALAM et al. 1986, RABIE et al. 1984, PAL et al. 1984, VERMA and NEUE,1984, FAGERIA 1985, BHIVARE and NIMBALKAR 1984). The reduction in dry matter yield under a salt stressed environment is probably due to the osmotic effect which lowers the osmotic potential of the medium, a possibility under arid and semi-arid environs (HOFFMAN & RAWLlNS 1971).

Considerable differents in the mineral elements content of leaves of the test plants were induced by the different salinity levels (Table 4-10). Sodium content of all the species was highly significantly increased at increasing salinity levels (Table 4). The increase was almost linear with the increasing salt concentration. LUNIN et al., (1964) with vegetable crops and EL-SHOURBAGY & MISSAK (1975) with three varieties of castor bean reported that sodium increased progressively with saline irrigation. The extent of Na accumulation with saline solution varied among the five test species; the highest was estimated in Aegilops bicornis (V₁) which normally contain the highest concentration of sodium.

The total nitrogen content of leaves of all the test soecies was highly significantly increased at all salinity levels (Table 5), and the increase was almost linear with the increasing salinity levels. ALAM et al. (1986) reported an increased nitrogen content in three vegetable crops at increasing salinity levels. On the other hand, salinity induced a reduction in the total N content of wheat and radish (HEIKAL 1977). Similarly, HUTTON (1971) with leguminous crops, PAL et al. (1984) with barley, BALKI and PODOLE (1982) with rice and MASHHADY et al. (1982), with maize reported that salinity resulted in a reduction in total nitrogen content. The phosphorus content in all the test plants increased with increase salinity levels. The highest content of P was recorded in Aegilops bicronis (V₁), while in the rest of species, P content was more or less same (Table 6). The reports indicate stimulatory (ALAM et al. 1986, MATOH et al. 1986, SAMENI et al. 1980) as well as inhinitory (AGARWALA et al. 1981, STARCK & CZAJKOWSKA 1981) effect on P content.

A reduction in content of K in the tops of Aegilops and Triticum species at all the levels of NaCl and Na₂SO₄ salinities was noticed (Table 7). However, favourable JOOLKA et al. 1977, GORHAM et al. 1985, MATOMATSU et al. 1982) as well as adverse (HAJRASULIHA 1980, GIRIRAJ et al. 1976) effects of salinization on K content in different agricultural crops have been reported. The decrease in K and increase in Na concentration in all Aegilops and Triticum species with increasing salinity symbolizes the antagonism between Na and K. Among the species, Aegilops bicornis (V₁) has greater preference for the uptake of K even under stress condition.

Calcium content significantly increased progressively in all the species with increasing salinity levels (Table 8). ASANA & KALE (1965) with four varieties of wheat, GEORGE (1967) with some cereal crops, VERMA & NEUE (1984) with rice indicated that Ca content appreciably increased with increasing salinity levels. With increasing salinity levels the concentration of iron in all the test plants significantly increased (Table 9). The highest content of iron was recorded in Aegilops bicornis (V₁) and lowest in Aegilops ovata (V₂). This result confirms the finding of MAAS et al. (1972). On the other hand, a decrease in Fe in the tops of NaCl treated tomatoes plant has also been reported (ALAM et al. 1986). Managanese content decreased with increasing salinity levels in all the test plants (Table 10). Similar results have been reported by ALAM et al. (1986) with tomato plants.

It would appear that the response of different species to salinity depends on the degree of salt tolerance of these wild species and triticale and the extent of salinization of the growth medium.

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