Refine search
Results 441-450 of 1,443
THE INFLUENCE OF STEM CUTTING LENGTH AND IBA TREATMENTS ON PROPAGATION OF NATIVE SAUDI ARABIAN GRAPEVINE
2005
B Hamooh
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 .
Show more [+] Less [-]NATURAL ENEMIES ASSOCIATED WITH MEALY PLUM APHID HYALOPTERUS PRUNI (Geoff.), (HOMOPTERA: APHIDIDAE) INFESTED APRICOT TREES, AT QALUBIA GOVERNORATE
2005
H Abul-Fadl | M El-Khawas | Salwa Abdel- Samad
The present work was carried out to study the population dynamics of the mealy plum aphid Hyalopterus pruni (Geoff.) and related parasitoids and predators on apricot trees, during the two successive seasons, 2003 and 2004, at Qalubia Gover-norate. The obtained data revealed that, the occurrence of H. pruni on apricot trees covered 5 months (from February to June). The mean total numbers of this aphid species per season were 1.78 (0.01-6.37) and 2.83 (0.00-10.01) individuals./leaf. The maximum numbers of H. pruni were recorded during the 2nd weeks of April, 2003 and 2004. No aphid individuals were observed during the period extended from July to September, in the two studied seasons. Four species of parasitoids; namely Aphidius matricariae Hal., Lysiphylbus sp. (1ry parasitoids) and 2 species of Alloxysta spp. (2ry parasitoids) were recorded during this study, attacking H. pruni. These parasitoid species were found during nearly three months of each season, in connection with the population density of the previous aphid species. The first para-sitoid was the highest in its numbers. The total numbers of predatory species per season were 407 and 1082 individuals, in the two studied seasons, 2003 and 2004, respectively. The maximum monthly occurrence of these predatory species was dur-ing April, 2003 (146 individuals) and April, 2004 (581 individuals), respectively. The predator Chrysoperla septempunctata L. had the highest percentages of occur-rence among other recorded predatory species (52.83 and 73.01%, respectively). In general, the parasitoid A. matricariae and the predator C. septempunctata, could be mass reared and released for controlling H. pruni on apricot trees with other availa-ble safe control methods developed in Integrated Pest Management (IPM) programs against this pest.
Show more [+] Less [-]OCCURANCE OF LAYING WORKERS AT DIFFERENT HONEY BEE COLONIES STATUS
2005
A Elbassiouny
Laying workers expressed as Workers with Activate Ovaries (WAO) having ma-ture oocytes had been studied in colonies headed with natural mated carnica queens. The results showed that the WAO were affected by the age of the queen, where it reached 0.8, 1.3 and 2.2 % for colonies headed with queens 10, 20 and 30 month old, respectively. The worker ovaries started to activate when the reached 22. 18 and 12 days from emergence for colonies headed with caged mated queens, caged virgin queens and queenless colonies, respectively. Also, when the worker's age reached 30 days, the percentages of WAO occurrence reached 3.3, 7.3 and 14.7 % for the corre-sponding colonies status, respectively. In preparing swarm boxes, when the bee-keepers failed to introduce the queens into the nuclei until two days, one week and two weeks, the WAO recorded 1.4, 4.8 and 9.2 %, respectively. In case of queen rearing, the presence of WAO was not significant until the fifth day, and then in-creased gradually to reach an average of 4.6% in the tenth day.
Show more [+] Less [-]Some Natural and Chemical Compounds Directly Affect Pests of Mulberry Trees and Their Side Effects on Silkworm Larvae
2024
Mai Hassanein | Youssef Abdalla | Sawsan Abdelmegeed
Mulberry trees suffer from many pest infestations. To control these pests, some natural compounds such as Techno Oil and Top 9 and some other chemicals such as Mospilan® and Chinook® were used. Mulberry trees, Morus nigra were treated with three different concentrations of each of Chinook, Techno Oil® and Top 9® to reduce infestation with Icerya sp. and Ferrisia virgate. A high reduction rate of more than 90% occurred when using these pesticides. On the other hand, the corrected mortality of mulberry silkworm larvae was 93.3%, 0.0% and 6.7% respectively after 8 days of treatment. When treating mulberry trees Morus alba with two different concentrations of each of pesticides; Mospilan and Techno Oil against whitefly, the average rate of infestation reduction was 100% and 94.94%, respectively. The corrected mortality of mulberry silkworms' larvae was 100% and 0.0% after 8 days of treatment respectively. This study proved that natural compounds could be used safely instead of chemical pesticides to reduce the pest population without affecting the life of silkworm larvae or cocoon properties.
Show more [+] Less [-]Isolation of Proline-Rich Protein Gene from Potato under Drought Stress
2024
Heba Mohammed | Mohamed Abdel-Salam | Ayman Hanfy | Mervat Diab | Nouh Ahmed | Emad Metry
Drought stress is considered one of the main factors that reduce plant growth, development and production. Therefore, studying plants during drought stress is highly useful to discover the newly gained characteristics of plants. The potato is considered one of the most important crop with economic value in Egypt and over the whole world. The main target is the proline-rich protein extracted from potato plants under drought stress. A stress experiment was applied to two potato (Solanum tuberosum L.) cultivars Desiree and Diamante. The stress experiment was conducted by poly-ethylene glycol (PEG) 4000; the used water potentials were: zero (control), (PEG 2%), (PEG 4%) and (PEG 8%), after drought stress, the solutes accumulation in the two potato cultivars were determined. Increasing drought stress through elevating PEG decreased leaf area as well as shoot and root lengths. Incontorary, the chlorophyll and proline contents increased with increasing PEG treatments. The proline-rich protein gene was cloned to the pGEM-T Easy vector and was submitted to the gene bank to be used later for enhancing drought resistance in other cultivars.
Show more [+] Less [-]Influence of Different Biological Treatments on Fermentation of Soyabean and Sunflower Meals
2024
Zeinab Mohammed | Hany Gado | Ahmed Mansour | Etab Abd El-Galil
This study examines fermented soya bean (SBM) and sunflower meal (SFM) with three biological treatments: Aspergillus Oryza, Ruminococcus flavefaciens and Lactobacillus plantarum, as well as the effects of these treatments on chemical composition, cell wall constituents, in vitro dry matter disappearance (IVDMD), and enzyme activity of the fermented SBM and SFM. After 2 h of ruminal incubation, all biological treatments (fungi, Bacteria, fungi with Bacteria) improved the IVDMD for Fermented SBM compared to that of the control (19.47, 20.65 and 18.38%, respectively). The maximum improvement values of IVDMD for SBM were recorded after 4 h and 6 h of incubation for all treatments. In addition, SFM after 2 h of ruminal incubation with any examined biological treatment (fungi, Bacteria, fungi with Bacteria), the IVDMD values have improved compared to that of the control group. Moreover, enzyme activities (cellulase, amylase, xylanase, and protease) have increased in all treatments. It was determined that SSF with A. oryzae and Ruminococcus boosted the protein content and digestibility of soybean and sunflower meals.
Show more [+] Less [-]The Potential Efficiency of Lactobacillus farraginis Isolated from Ruminants with a View to be Used as Animal Probiotics
2023
Mona Zayed | Dalia Abd El-Fattah | Rateb Abbas | N. El-Bordeny | Sherif Edris
Probiotics refer to microorganisms that exhibit a beneficial effect on the animals’ health through intestinal microbial balance. This investigation intends to identify and define the probiotic characteristics of Lactobacillus strains isolated from the digestive systems of ruminants. Bacterial strains were isolated purified and characterized based on morphological and biochemical characteristics. The isolates were identified using the 16S rRNA gene partial sequencing method. Most of the strains exhibited a decrease in the growth by increasing the concentration of the bile salt, NaCl, increasing the temperature over 37oC, and moving toward neutrality and alkalinity of the media. Strain Lactobacillus farraginis MD_A11 revealed the lowest decrease in the growth percentage when subjected to different bile salt concentrations of 5.96, 6.61, 6.85, 7.40, 7.53, and 7.64%, NaCl% concentrations of 1.40, 5.62, 6.48, 7.36, 7.39, 7.41, 7.42, 7.28, and 13.76%, raising the temperature over 37oC being 4.19 & 3.945%, different pH levels as compared to control, and it recorded the lowest medium pH after the third day being 4.20 with titrable acidity of 0.32%. Strain Lactobacillus farraginis MD_A11 could be recommended as a probiotic feed additive for ruminants to improve their growth performance and productivity.
Show more [+] Less [-]Effect of Gamma Radiation on Ephedrine and Pseudoephedrine in Callus and Suspension Cultures of Ephedra alata
2023
Naglaa Abdelsalam | mona Abd El-Aal | mohamed Aboul Fotouh | mohamed Reda | Ibrahim Safe
Ephedra is the most widely and largest widespread genus in the Gnetopsida, a subgroup of the gymnosperms. This research was done to find out how gamma radiation affected the in vitro growth of callus and suspension cultures. In addition, the effect of gamma rays (γ-rays) on the ephedrine and pseudoephedrine concentrations was evaluated through HPLC analysis. The cell suspension and callus cultures were formed on Murashige and Skoog's basal medium (MS) supplemented with 0.5 mg/l kinetin (Kn), and 3 mg/l of 2, 4-dichlorophenoxy acetic acid (2,4-D) and exposed to variable gamma radiation doses (0, 5, 10, 15, 20, 25 and 30 Gray). Highly significant differences in both fresh and dry callus weights were recorded due to the effect of gamma rays (γ-rays). The findings demonstrated that in the cell suspension and callus cultures, 15 Gray achieved the highest fresh and dry weights when compared to the control. Similarly, the highest concentrations of ephedrine and pseudoephedrine were found in suspension and callus cultures compared to control at 15 Gray.
Show more [+] Less [-]Molecular Identification of Some Rhizobium and Serratia Isolates as Potential Producers of Indole-3-Acetic Acid
2023
Shaimaa Sello | Ashraf Abdel Razik | Samir Ibrahim | Sawsan Elateek
In order to reduce the use of chemical fertilizers, the use of biological inoculants has been increased. Beneficial microorganisms are used to increase crop yields by stimulating plant growth through the production of phytohormones. In the present study, Indole Acetic Acid (IAA) production was analyzed in 18 bacterial isolates with Plant Growth-Promoting (PGP) capabilities; 15 of these isolates were Rhizobium, and three were Serratia. All isolates have been characterized morphologically and biochemically, and their IAA production in the presence of tryptophan, a precursor for IAA biosynthesis, has been evaluated. IAA production was detected using the Salkowski reagent with CT-2200 spectrophotometer at 530 nm. The levels of IAA production varied between the different isolates. The top two IAA producers were selected for genetic identification using 16SrRNA primers (27F and 1492R). One of the Rhizobium isolates (NRC-R2) shared 95% sequence similarity with Rhizobium sp., according to a Blastn search in GenBank and Rhizobium leguminosarum, whereas the Serratia isolate (Ain Shams Center for Genetic Engineering and Biotechnology (ACGEB)-S2 was 99.5% similar to Serratia sp. Accordingly, these two isolates could serve as biological sources for IAA.
Show more [+] Less [-]Effect of Rumen-Protected Choline Supplementation on Growth Performance of Fattening Calves
2023
Abdelrahman Amin | Ahmed Marwan | Fouad Abdelaziz | Nasr Elbordiny
This study aimed to evaluate the influence of choline chloride supplementation on the growth performance of feedlot calves. Thirty-two crossbred calves with a mean initial body weight of 305.71±4.09 Kg were divided into three groups of 10, 11 and 11 animals, randomly. The animals were distributed to one of three dietary treatments, control, choline15 and choline 30 (the rations supplemented with 0, 15 and 30 g choline chloride, respectively). The animals were fed on concentrate feed at a rate of about 2.15% of their live body weight and rice straw open access. Supplementing animal ration with choline chloride did not significantly affect all nutrients' digestibility and feeding value. The animals supplemented with 30 g choline chloride recorded significantly higher (P=0.037) total serum protein concentration compared to the other groups. The group received a ration supplemented with 30 g of choline chloride and recorded significantly higher final weight, total gain, and mean daily gain. Data showed significant improvement in TDN, CP and DCP conversion for the animal received ration supplemented with 30 g choline chloride compared to the control group. In conclusion, supplementing fattening calves' ration with rumen-protected choline could improve average daily gain and feed conversion.
Show more [+] Less [-]