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In field trials conducted over 8 years the effect of sowing depth on plant establishment, tillering capacity, plant height, grain yield, top growth weight and patterns of root development of wheat and barley was studied. Establishment, number of grainbearing tillers per established plant, plant height at maturity and grain yield and top growth weight per plot as well as per plant were reduced with increase in sowing depth from 2 to 20 cm. Seedling emergence started earlier from large seeds and from shallow sowing. Establishment from large seeds of two varieties was better, especially for deep sowing and in clay soils. Several patterns of root and tiller development were observed at various sowing depths. Varietal differences in stand establishment under field conditions were not related to plant height. It was concluded that deep sowing beyond around 10 cm should be avoided because stand and plant vigour are adversely affected.

The effect of stage of harvesting on dry-matter (D.M.) yield and chemical composition of barley, wheat and the legumes common vetch (F. sativa), woollypod vetch (F. dasycarpa) and fodder peas (P. sativum) were studied in Cyprus under low rainfall conditions in a series of trials sown in four successive years. Cereals were harvested at the beginning of heading, 50 % heading and the milk stage of grain, and legumes at three stages from preflowering to full pod formation, D.M., protein and digestible D.M. yields and percentage D.M. content increased with age, whereas percentage protein content and D.M. digestibility declined. Under moisture stress conditions before and during the harvesting period D.M. yields did not increase significantly with age. Protein content of cereals under low rainfall conditions was higher than that of cereals grown in the U.K. under higher N fertilization levels. Rainfall conditions affected drastically the performance of both cereals and legumes. However, average yields were satisfactory; the barley variety 628 gave 8-98 t/ha, the highest D.M. yield among all cereal and legume varieties.

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Data collected from 1968 to 1981 were used to study the effects of annual precipitation and its distribution on grain yield of three barley and six wheat varieties from 19-47 environments.The percentage of the variation in grain yield explained by annual precipitation varied with variety and species (5-31 % in barley and 31-79 % in wheat). The distribution of precipitation was the major factor affecting grain yield, although it varied with variety, and explained 72-92 % of the variation in barley and from 75 to 98 % in wheat.Only 33 of the 144 simple correlation coefficients between grain yield and precipitation during each of the 16 fortnightly periods were significant. The expected average effect on yield due to additional precipitation above the mean showed positive effects in barley during the presowing and heading to flowering periods; no consistent trend was found in the wheat.Improved agronomic practices could alleviate the adverse effects of the low and unevenly distributed precipitation by reducing losses and increasing storage of water in the soil. Breeding could contribute greatly towards high and stable yields in drylands.