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Carob (Ceratonia siliqua L.) is an environmentally and economically important tree and is among the most difficult to propagate fruit species. In this study, efforts were made to propagate the plant by using three different methods; seeds germination, cuttings and micropropagation. Seeds and cuttings were scarified and disinfected under aseptic conditions to improve the germination percentage and the percentage of success of cuttings in April and September through two successive seasons (2011 and 2012). Results showed that the highest values of seed germination percentage, the fastest germination, the greatest plant length, number of leaves/plant, root length and dry weight were obtained by soaking seeds in 60% H 2 SO 4 in April and September through the two seasons, but there was no significant difference between the first and the second date in both studied seasons for most of the studied parameters. April was found the best time for propagation of Carob by cuttings, for all treatments. Besides, carob cuttings treated with indole-3-butyric acid (IBA) at 8000 mg/l + βnaphthalene acetic acid)NAA(at 200 mg/l gave the highest values of parameters (shoot length, no. of lateral shoot, no. of leaves/plant, root length, no. of roots/plant and root dry weight) followed by IBA at 6000 mg/l + NAA at 200 mg/l, in both seasons. While, all cuttings failed to root for all treatments in September, except when they were treated with IBA at 6000 mg/l + NAA at 200 mg/l and IBA at 8000 mg/l + NAA at 200 mg/l, in the two studied seasons. Micropropagation of carob was developed by using shoot tips and stem node segments, of ex vitro grown seedlings, as explants. Hundred % of growth induction was obtained, for both explants, with the highest number of shoots on Murashige and Skoog (MS) medium containing 0.4 mg/l NAA + 2 mg/l 6benzylaminopurine (BAP). Shoots were best multiplied on MS medium containing BAP (1.0 mg/l), while the media containing N6-(2-isopentenyl) adenine (2iP) gave the highest lengths of shoots (2iP at 1.0 mg/l). For further elongation and multiplication of shoots, the combination of both BAP and 2iP gave promising results at concentrations of 0.5 mg/l BAP + 0.5 mg/l 2iP or 1.0 mg/l BAP + 0.5 mg/l 2iP. Attempts to achieve rooting were unsuccessful, since only shoot development was observed.

Plant population density plays an important role on crop growth and yield as response to light penetration and photosynthesis rate. A field experiment was carried out at Sids Research Station, Agricultural Research Center (ARC), during two successive winter seasons, of 2012/13 and 2013/14. The objectives of this investigation was aimed to evaluate five faba bean genotypes namely Nubaria 1(large seeded cultivar), Giza 429, line 43130, E.19 (medium seeded types) in addition to the small seeded type Camolina. Plant densities were; a) 8 plants/m 2 planted in single seeded hills spaced 20 cm on one side of 60 cm wide ridges, b) 17 plants/m 2 planted in double seeded hills spaced 20 cm on one side of the ridges, c) 17 plants/m 2 planted in single seeded hills spaced 20 cm on both sides of the ridges and d) 33 plants/m 2 planted in double seeded hills spaced 20 cm on both sides of the ridges. Results indicated that, faba bean genotypes were significantly different in all studied characters. Nubaria 1 and E.19 genotypes had the tallest plants, respectively. The highest seed yield per feddan was obtained from Nubaria 1 cultivar, while the medium seeded line L-43130 produced the lowest seed yield per feddan over both seasons. Giza 429 (medium seeded cultivar) followed by Nubaria 1. Plant population of 17 plants/m 2 in single seeded hills on both sides of the ridges produced highest seed yield per feddan over all genotypes. Concerning to the interaction between plant populations and faba bean genotypes, highest seed yield per feddan was obtained from the large seeded cultivar Nubaria 1 under the low plant population (8 plants/m 2 ), while the medium seeded types i.e. Giza 429, L-43130 and E19 were more yielding under the third plant population (17 plants/m 2 on both sides of the ridge). On the other hand, the small seed type Camolina produced highest seed yield per feddan under the high plant population (33 plants/m 2 ). The interaction between faba bean genotypes and plant population had significant effects on all studied characters except number of days to flowering.

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The population of the green stink bug Nezara viridula L. was estimated by conducting periodic survey during the years 1975 and 1976. It was expressed as number per 100 double strokes. Overwintering adults resumed activity by mid of March, and the population attained its maximum by mid of April. The number of adults in either spring or late summer correlated closely with population size of nymphs. All nymphs developing in August produced adults that entered hibernal diapause. The insect had 4 generations in 1975, while only 3 generations were recorded in 1976. The overall sex ratio among field collected bugs was aproximately ♀: ♂, 1: 1. The effect of daily mean temperature, daily mean rel. humidity and day‐length on the population density of the green stink bug was investigated. A positive relationship was found between insect population density and each of daily mean temperature and day lenght, while rel. humidity showed different relations depending on season and year. The partial regression values and the percentages of the explained variance showed that the effect of the three climatic factors was high only in spring. These values also denote that there are other environmental and biological factors that play a great role in the variability of the population dynamic of the green stink bug population particularly during summer. Zusammenfassung Untersuchungen über die Phänologie und Ökologie von Nezara viridula L. (Heteropt.: Pentatomidae) Mittels periodischer Untersuchungen von 1975 bis 1976 wurden die Populationsdichte und ‐Änderungen (bezogen auf 100 Doppelschläge mit dem Käscher) von N. viridula erfaßt. Die überwinternden Adulten nahmen ihre Tätigkeit gegen Mitte März wieder auf. Die Population erreichte ihr Maximum um Mitte April. Die Zahl der Adulten im Frühjahr oder Spätsommer stand mit der Populationsgröße der Nymphen in engem Zusammenhang. Alle noch im August entwikkelten Nymphen ergaben Adulte, die in Winterdiapause gingen. Die Wanze hatte 1975 vier Generationen, 1976 nur drei. Das Geschlechterverhältnis betrug bei den gefangenen Tieren annähernd 1:1. Weiterhin wurden die Beziehungen der täglichen mittleren Temperatur, der täglichen mittleren LF und der Tageslänge zur Populationsdichte der Wanze untersucht. Eine positive Beziehung bestand zwischen der Dichte einerseits und der täglichen Mitteltemperatur bzw. Tageslänge andererseits, während die rel. LF nach Jahr und Saison schwankte. Die statistische Auswertung zeigte, daß die Wirkung der drei genannten abiotischen Faktoren eine wesentliche Rolle in der Populationsdynamik von N. viridula, hauptsächlich während des Sommers, spielen.