Identification and understanding of the mechanism of drought tolerance in wheat (Triticum aestivum L.) cultivars has long been a major goal of plant breeders. Our objective was to determine if leaf water potential, osmotic potential, yield, and yield components could be used to differentiate apparent drought tolerance among the cultivars. Four spring wheat cultivars (Giza 165, Gemmiza I, Klassic, and SPHE3) from different geographic regions were grown in a greenhouse at 20/ 15°C with 12 h of daylight augmented with artificial lighting and subjected to water stress imposed by withholding irrigation at different stages of growth. The three treatments were: no stress (WI); I0 stress at tillering OV2); and I0 d stress at heading OV3). Water stress caused large differences for yield and yield components. For the W3 treatment, Giza 165, Gemmiza I, and SPHE3 had yield decreases of 44%, 43%, and 18%, respectively, while Klassic had a yield increase of 4%. The average slopes of the turgor vs leaf water potential plots were 0.56 for Giza 165 and Gemmiza I vs 0.43 for Klassic and SPHE3 at heading. The difference between the two groups was statistically significant as determined by the 95% Tukey test. Stress applied at either tillering or heading gave similar results but effects were more pronounced when stress was applied at heading. It was not possible to determine if osmotic adjustment contributed to the differences between cultivars in response to water stress.

Insects visiting flowering Vicia faba, Eruca sativa and Petroselinum crispum in Nahia fields in Egypt were recorded by netting at different day hours 9–10, 11–12 a. m., 1–2, 3–4 and 5–6 p. m. All visitors of V. faba were from family Apidae. Most important species were: Anthophora sp. (81.32%), Tetralonia lanuginosa (7.69%) and Chalicidoma siculum (6.59 per cent). Most of insect species were active at 11–12 a. m. and 1–2 p. m. Syrphus corollae (45.9%) was the dominant visitor of Eruca sativa and Andrena sp. (85.3%) was the most numerous species at Petroselinum crispum. Zusammenfassung Bestäubende Insekten auβer der Honigbiene bei einigen Kulturpflanzen in Ägypten Es werden die bei Vicia faba, Eruca sativa und Petroselinum crispum im District Nahia aufgetretenen blütenbesuchenden Insekten (Netzfänge an 5 Tageszeiten: 9–10, 11–12, 13–14, 15–16 und 17–18 Uhr) zusammengestellt. Alle Besucher von V. faba gehörten der Familie Apidae an. Wichtigste Arten waren Anthophora sp. (81,3%), Tetralonia lanuginosa (7,7%) und Chalicidoma siculum (6,6%). Die meisten Besucher kamen zwischen 11 und 12 sowie 13 und 14 Uhr. Syrphus corollae (45,9%) war die Hauptart bei Eruca sativa, während Petroselinum crispum von Andrena sp. (85,3%) am meisten besucht wurde.

Milk yield of 270 Rahmani, Ossimi and Barki subtropical Egyptian ewes rearing single lambs during three successive lambings in 2 years was estimated over 12 weeks of the lactation using a lamb-suckling technique. The ewes received either normal or high level of feeding during late pregnancy and lactation.Ossimi and Rahmani ewes showed significantly (P < 0-01) higher total milk production than the Barki. Milk yield declined sharply for the Barki ewes after the 6th week of lactation. Breed variation failed to attain statistical significance in the first 4 weeks of lactation. The highly fed ewes produced significantly (P < 0-01) more milk at different stages of lactation than the normally fed ones. High level of feeding, however, is not recommended for subtropical non-dairy ewes as it is not economic. Spring-lambing ewes produced significantly more milk during the first 8 weeks of lactation, while the summer-lambing ewes were more persistent in their milk yield in the last 4 weeks of lactation.

SummaryMilk yield of 240 single-suckled ewes from Rahmani, Ossimi and Barki subtropical non-dairy Egyptian sheep, in addition to 64 twin-suckled Rahmani ewes, was estimated over two lambing seasons using three methods of measuring, i.e. lamb-suckling (plus residual milk), oxytocin technique and hand milking.For single-suckled ewes, the oxytocin technique resulted in higher (P < 0·05) estimates of milk yield during the first 4 weeks of lactation than lamb-suckling. However, over 12 weeks of lactation the two methods showed closely similar estimates. Hand milking produced 31·6% less milk than the other two methods.For twin-suckled ewes, the lamb-suckling method produced significantly (P < 0·05) higher estimates than the oxytocin technique. Estimates obtained by hand milking were 65·2 and 50·8% less than that of the other two methods, respectively.

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