In Libya the plants Myrtus communis and Plantago albicans are commonly used in folk medicine to treat various diseases. However, there are a large number of plant compounds which can cause many aberrations in genetic material. This study was carried out to investigate any possible cytotoxic and mutagenic effects for M. communis and P. albicans on mitotic criteria of cell cycle and chromosomes. Two infusion concentrations were prepared for each plant, one of them was used as folk medicine (o.25 mg/ml) and other as to 10 times of this value (2.5 mg/mL). Bean (Vicia faba, L.) root-tip cells (RTC) and Balb / C mice (Mus musculus) bone-marrow cells (BMC) were used as test systems. The M. communis infusions at both concentrations and the P. albicans infusion at the lower concentration had no statistically significant depressive effect on mitotic criteria of RTC. Where as significant depressive effect on these criteria of RTC was found for the high concentration of P. albicans as compared with a negative control. No significant effect on the induction of chromosome aberrations and the rate of mitotic index of BMC was found by using infusions of P. albicans and M. communis as compared with control.

The effect of infection of Biomphalaria alexandrina snails with Bacillus thurin-giensis kurstaki on various stages of Schistosoma mansoni life cycle was studied for three successive generations. Thus, two groups of snails were exposed to a sublethal concentration of the bacteria (0.08 gm/L water) containing 32000 IU/mg, for one week and to schistosome miracidia. One group was exposed to the miracidia before bacterial infection, while the other group to the miracidia after the bacterial infec-tion. Cercariae produced from each group of snails were used to infect albino mice. The infection of snails and mice with the parasite was repeated for three generations of the parasite. In the first case, data obtained show that the schistosome infection rate of snails was considerably reduced being 60%, 18%, and 66.6% versus 90 % , 92% and 90% in untreated control snails in the three generations of the parasite, re-spectively. Meanwhile, the mean prepatent period was extended being 29.1  4.3 days, 33  1 days and 38.5  2.5 days versus 27 days in the control group. The num-ber of worms recovered from infected mice showed reduction of 52 %, 78.4% and 58.6%, respectively. In the second case, the infection rate of snails was 40%, 16% and 73.7% for the three successive parasite generations and the prepatent period was 32  1 days, 32  2.3 days and 35  2.8 days, respectively. The reduction percentage of the recovered worms was 34.8, 73.6 and 72.9 in the sccessive generations, respec-tively. The present results prove that infecting B.alexandrina snails with a sublethal concentration of B. thuringiensis kurstaki bacteria exhibits clear negative effect on the transmission of S. mansoni in three successive generations. So, it could be rec-ommended to use B. thuringiensis kurstaki as a potential biocontrol agent against S. mansoni.

A test survey was conducted to determine the nutritional status of apple trees grown at four highly productive orchards in south of Jordan. Leaf and soil samples were taken from each orchard, and analyzed for the concentrations of macro- and micronutrients. Soils of Al-Shoubak tend to have high pH, low organic matter and high CaCO3 contents. The results showed that soil concentrations of N, K, Fe, Mn, Zn and Cu varied widely among the orchards. No deficiency or hunger signs of N, P, K, Mn and Zn nutrients were observed at any of the localities since concentrations of leaf nutrients were generally within the sufficient range, indicating adequate lev-els of fertilization applied to the trees. The leaf analysis has shown that Cu deficien-cy is found in some apple orchards. Soils and leaf nutrient levels were generally not well correlated with one another. The only highly significant correlation was be-tween soil P and leaf N. However, positive relations were observed among leaf P and Mn, Fe and Mn, Fe and Zn, and Mn and Zn contents.

Stem node explants of three almond (Prunus dulcis Mill) cultivars (Om – Elfahm, M-Dalt and Ne Plus Ultra) and the hybrid rootstock “Hansen” cv. were suc-cessfully established and proliferated on Murashige and Skoog medium (MS) sup-plemented with benzyl adenine (BA) at 0.0 - 2.0 mgl -1 and indol butyric acid (IBA) at 0.0 - 0.1 mgl-1 .The highest bud development percentage of stem node explant was obtained with medium contained BA at 2 mgl-1 with or without IBA at 0.1 mgl-1 for M – Dalet and Ne Plus Ultra almond cultivars compared with other treatments. The longest shoot during establishment stage was recorded by “Hansen” rootstock cultured in MS with BA at 2.0 mgl-1 plus IBA at 0.01 mgl-1.Using BA at 1.0 mgl-1 plus IBA at 0.1 mgl-1 and BA at 2.0 mgl -1 plus 0.05 or 0.1 mgl -1gave the highest number of proliferated shoots for Om – Elfahm, M-Dalt and Ne Puls Ultra cvs. and “Hansen”, respectively in the 3rd subculture. The best average proliferated shoot length was achieved with medium supplemented with BA at 1.0 mgl-1 plus IBA at 0.05 mgl-1 or 0.1 mgl-1 for M-Dalt, Ne Puls Ultra and “Hansen” respectively, where-as, using BA at 2.0 mgl -1 plus IBA at 0.1 mgl -1 recorded the longest average prolif-erated shoot for Om- Elfahm cultivar. Microshoots were rooted in modified Bourgin and Nitsch medium supplemented with IBA or NAA at 1.0 mgl-1 only or combination (0.2 IBA mgl-1 + NAA 0.4 mgl-1, IBA 0.4 mgl-1 + NAA 0.8 mgl-1 and IBA 0.5 mgl-1 + NAA 1.0 mgl-1). The large callus (more than 10 mm diameter) was recorded with “Hansen” rootstock and Om – Elfahm treated by IBA at 0.4 mgl -1 plus NAA at 0.8 mgl -1. The greatest rooting percentage (66.67%) was obtained with medium contained IBA at 0.2 or 0.4 mgl-1 plus NAA at 0.4 or 0.8 mgl-1 for “Hansen” rootstock and Ne Plus Ultra shoots.

Seeds of the tooth pick plant (Ammi visnaga L.) were extracted by organic sol-vents of different polarities, and tested for their toxic effect on Sitophilus oryzae in-festing wheat grains. Toxicity of chloroform extract, was the most potent, at both Lc50 and Lc95 levels (i.e. 3240 and 8730 ppm). Reproductive potential of treated weevil were strongly affected as no progeny were obtained when treated with either Lc50 or Lc95 with A. visnaga. Extracts treatment at Lc95 level organic extract gave protection up to 12 weeks for petroleum ether and chloroform, and 9 weeks when acetone was used for extraction. All tested extracts reduced grain germination at the end of 14 weeks storage period. Also, treated wheat grains with tooth pick extracts reduced the weight loss of grains.

The most important black table olive (Olea europaea L.) “Kalamata” cultivar, grafted onto three different vegetative olive rootstocks[Picual (Pic), Frantoio (Fra) and Koroneiki (Kor) cvs.] was evaluated with 2-year-old grafted plants grown in sand clay soil, and received concentrations of salt mixture (NaCl, Na2So4, CaCl2, MgSo4 and KCl) making 6000 and 8000 ppm with SAR 12 of salinity level, for two seasons. Morphological and chemical parameters were investigated to determine the relative salinity tolerance of these rootstocks and to define possible reasons for any observed differences in the salt tolerance. However, results indicated that differences in response to salinity among rootstocks were observed primarily in morphological traits. Increasing of salinity level in irrigation water decreased, all of scion height and its rate of increase, leaf area, number of leaves/plant and fresh & dry weight of leaves and roots. But different rootstocks can affect the degree to which these pa-rameters is reduced under salinity, where Kalamata growth on Picual and Frantoio was considerably better than on Koroneiki at 6000 and 8000 ppm treatments. In-versely in untreated grafted plants Kalamata on Kornaki exhibited the best growth vigor, comparing with Kal/Pic or Kal/Fra plants, suggesting that a decrease of scion growth in untreated grafted plants is a salt tolerance quality transmitted by tolerant rootstocks. Salinity significantly decreased leaf chlorophyll (a) and (b) content of all grafted plants, but different content among rootstocks were noted. On the contrary, proline content increased in leaves of all treated plants, however, insignificant dif-ference was noted between rootstocks, yet the interaction between the two factors show that Kalamata on Picual and on Frantoio rootstocks recorded higher values of leaf proline content than Kalamata on Koroneiki rootstock. Leaves and roots Na+ and Cl- content of treated grafted plants showed an increment but to a different de-gree, comparing with the untreated (control) plants. There were differences among the grafted plants where Kalamata grafted on Koroneiki (the least tolerant cv.) most-ly affected by saline treatment and accumulated the highest content of Na+ and Cl- in leaves comparing with Kalamata on Picual (the most tolerant cv.) or on Frantoio (the Sanaa LazArab Univ. J. Agric. Sci., 13(2), 2005400moderate tolerant cv.). Tolerant rootstocks contained more Na+ in roots than in leaves. This response become apparent as salinity increased. Leaf N, P and K con-tents decreased in Kalamata leaves as influenced by different rootstocks and increas-ing salinity in irrigation water comparing with the control. Kal/Pic and Kal/Fra plants had higher N% in leaves than Kal/Kor plants, whereas Kal/Pic accumulated K more than the other plants, while P content in leaves of all grafted plants were insig-nificant in the two seasons. Based on the overall growth parameters and chemical composition in response to salinity, Kalamata grafted on Picual exhibited the great-est salt tolerance followed by those grafted on Frantoio whereas, Kalamata on Koro-neiki showed the poorest plants pertaining salt tolerance.

The present study was carried out in an olive orchard at 6th of October city, Giza Governorate, Egypt during 2002 and 2003 growing seasons on “Aggezi” and “Koroneiki” olive cultivars for table and oil purposes, respectively. The objective of this study was to investigate the effect of organic farmyard manure (FYM), compost (COM) manure and biofertilizers (Bio) as the combination between phosphorene and nitrobeine, calcium citrate (Cac) and potasseine (K). Besides, the fertilization program adopted in the farm [N (750g/tree), P2O5 (600g/tree) & K2O (500g/tree)] was used as control. The results revealed that, the application of different aforemen-tioned treatments increased significantly shoot growth (length and diameter, number of leaves shoot and area/leaf) compared to the control in both cultivars (Aggezi and Koroneiki) during the two growing seasons. In this concern, the application of FYM+Cac influenced significantly shoot length & diameter, number of leaves/shoot and area/leaf of Koroneiki cv. and shoot diameter of Aggezi cv. Meantime the area /leaf of both cvs.increased when fertilized by FYM+COM+Cac. Whereas, the com-bination of FYM, COM, Cac, Bio, and K improved significantly blooming charac-teristics (number of flowers/inflorescence, inflorescence length and perfect flowers %) of Aggezi and Koroneiki olive cvs. However, number of fruits/shoot and yield of both cultivars increased significantly when treated by the combination of organic and biofertilizers, especially FYM+COM+Bio. Moreover, pulp/seed ratio was in-creased when treated with FYM+Bio (especially in 1st season). In addition, Koro-neiki cv. when provided with FYM+COM+Bio treatment produced the richest fruits in their oil content. Aggezi cv. trees when fertilized with the combination of organic manure & calcium, gave higher contents of chlorophyll (A), (B) & total chlorophyll, however, in Koroneiki cv. chlorophyll B didn't affect. Eventually, nutrient elements (NPK) contents didn't take a definite trend except for N which was affected signifi-cantly with the different combinations, while P & K in Aggezi leaves were influ-enced by FYM only. On the other hand, Koroneiki trees treated with COM+Bio had the highest leaf N content. Leaf P content was positively affected by FYM+Cac in 2002 and FYM+COM+Bio in 2003. Meantime, FYM+K followed by COM+Bio in-duced the highest stimulative effect on leaf K content.

In this study, three isolates of Streptomyces isolated from Egyptian soil at Giza Governorate and belonging to red series were identified based on their cultural, morphological and physiological characters. According to the key proposed by Pridham and Tresner (1974), the experimental isolates ST55, ST71 and ST86 ap-peared to be related to S. lincolnensis, S. venezuelae and S. umbrinus, respectively. In addition, random amplified polymorphic DNA (RAPD)-polymerase chain reac-tion (PCR) was used to amplify the DNA genome of the three applied isolates and an identified strain to determine their fingerprints. This was carried out using 10-decamer oligonucleotides, i.e., OP-A02, OP-D01, OP-D02, OP-D05, OP-D06, OP-D07, OP-D08, OP-D11, OP-D18 and OP-D20. The PCR amplified products were detected by electrophoresing on 1.5% agarose gel and visualized by staining in eth-idium bromide and UV trasilluminator. Results showed that the same oligonucleo-tide flanking fragments differed from one isolate to another with different sizes. Monomorphic and polymorphic fragments were amplified confirming the molecular relationships as well as the genetic diversity between the four applied strains of Streptomyces. Based on the statistical analysis of RAPD-PCR polymorphisms a de-gree of similarities ranged from 33.9 to 59.2 % was found. Furthermore, frag-ment(s), whatever absent or present, were found to be unique molecular markers and could be used for characterization of some isolates. This result supported the idea for using the RAPD-PCR technique for classification of Streptomyces isolates.

The Saudi Arabian Ministry of Agriculture experimental station at Al-Maddina Al-Monwarah region, identified very few plantations of the most productive Vitis vinifera var. maddini with the highest fruit quality. This research was designed to optimize rooting effeciency in relation to cutting length and auxin treatment. Cutting length (long vs short) showed strong impact on rooting ability. Results showed that longer cuttings produce more and longer roots than shorter ones. IBA treatments up to the 500 ppm level showed significant increase in root number, but do not have significant impact on root length. Rooted cuttings were planted in an open field for further evaluations. These findings may facilitate the clonal propagation of this val-uable vines at Al-Maddina Al-Monwarah region, grapevine growers and Horticultur-ists in Saudi Arabia .

This study was carried out at the Strawberry Improvement Center Experimental Farm, Nobaria, Beheira Governorate and the Horticulture Research Station, Bar-rage, Kalubia Governorate during 2001/2002 and 2002/2003 seasons. The study aimed to investigate the effect of calcium nutrition (0, 13and 26 kg/fed. Ca) and modified atmosphere storage (10,20, 30 and 40% CO2) on the post harvest decay of cold stored strawberry transplants and their subsequent fruit production. The results indicated that increasing the rate of calcium application during the transplant growth period and carbon dioxide concentration around transplants during the cold storage resulted in significant decrements in transplant decay, infection percentage, disease severity of roots and crowns. There was a positive relationship between cal-cium nutrition and early yield. Moreover, the highest calcium rate gave the highest total yield while no significant difference was noticed between control and 13 kg/fed treatments. This study concluded that adding Ca++ at 26 Kg /fed as fertiga-tion of calcium nitrate (13% Ca) to the growing strawberry transplants followed by modified atmosphere storage (40% CO2) during the prolonged cold storage allowed maintenance of transplant quality and increased their yield while minimizing decay development.