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A PROPOSED TAXONOMIC SYSTEM OF THE GENUS TRIBULUS L. IN EGYPT BY MEANS OF NUMERICAL TAXONOMY
2005
Kadria Ahmed
Numerical analysis of 62 morphological and histological characters extracted from the 2 previous papers (Ahmed and Mohamed, 2005, a & b) of the 7 studied taxa in the genus Tribulus led to their classification into two groups. The 1st contains 5 pentacyclic flowered taxa (T.terrestris, T. terrestris var. bicornutus, T.macropterus, T.megistopterus & T.mollis) with 2 basal vascular bundles in their small leaflets while the 2nd included 2 tetracyclic flowered taxa (T.kaiseri, T.pentandrus) with single main bundle. The resulted analysis arranged taxa of gp.I into 2 sections while that of gp.II into a third section. Tribulus besides possessing its own generic characters, also shares the Zygophylloid genera in major grounds. Therefore it is recommended to remain in tribe Tribuleae of Zygophylloideae within Zygophyllaceae and never isolated either into a family or even subfamily of its own.
Afficher plus [+] Moins [-]EFFECT OF IRRIGATION WITH SALINIZED WATER ON GROWTH AND CHEMICAL CONSTITUENTS OF “KALA-MATA” OLIVE CULTIVAR GRAFTED ONTO DIFFERENT OLIVE ROOTSTOCKS
2005
Sanaa, Laz
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.
Afficher plus [+] Moins [-]MORPHOLOGICAL AND ANATOMICAL VARIATIONS OF ANABASIS ARTICULATA ECOTYPES IN EGYPT
2005
Azza Khafagi | A. Marei | Sahar Mohamed
The present study has been carried out on ten stands of Anabasis articulata in Egypt. The relationships between the studied Anabasis articulata stands have been demonstrated as dendrogram based on the morphology, anatomy and some chemical constituents of the plants. Four characteristic ecotypes of Anabasis articulata have been recognized: (i) xerophytic ecotype in the stands of Belbase desert and Sudr El Hytat-Nekhl Road, (ii) xero - halophytiç ecotype in the stands of the Eastern Desert, Sinai Desert, Kattamia-Ain Sukhna Road, Isthmic desert (Fayid), Adabia and Saint Katherine, (iii) halophytic ecotype in the stands of the Red Sea Costal region, Ras Sudr and Hammam Faraon, Sinai and (iv) halo-xerophytic in the stands of the Nekhl-El Hasana and El Hasana-El Quseima Roads. These ecotypes differ, remark-ably, morphologically, anatomically and chemically. This may be due to the varia-tion in climatic and soil characteristics of the habitats
Afficher plus [+] Moins [-]QUALITY EVALUATION OF BEEF STEAKS WITH EDIBLE COATING DURING DEEP - FRYING
2005
Nessrien Yasin | Hanan Al-Sayed | Salwa Abo-El-Fetoh
Quality of fried beef steaks coated with sodium alginate, carrageenan and car-boxy methyl cellulose (CMC) at concentrations 0.3, 0.6 and 0.9% as well as oils used for frying were evaluated after several frying times (1, 3, 5 and 7 times). Weight loss, shrinkage, moisture loss and final lipid content of control sample were sharply increased after the first time of frying compared to other treatments. The lower reduction in weight loss was achieved in fried beef steaks coated with CMC at concentration of 0.9%. Samples coated with 0.9% carrageenan caused a considerable decrease especially in shrinkage and moisture loss followed by samples coated with CMC and then those coated by sodium alginate at different concentrations. The same treatment (0.9% CMC) showed the lower value of final lipid content. There were significant (p<0.01) decremental patterns in all of sensory attributes (appear-ance, flavor, color, juiciness, mouth feel, texture and overall acceptability) of fried beef steaks during subsequent frying times for all treatments. Less rates of these de-terioration were appeared in CMC samples with different concentrations followed by samples coated with 0.3% and 0.6% of sodium alginate. Progressive rise in acid value of frying oils was especially found in control sample during different frying times, on the other hand the low rate of increase was appeared in sample coated with 0.3% and 0.6% sodium alginate. The higher values of K232 appeared in control sam-ple followed by 0.9% CMC but lower value recorded by oil used for frying beef steaks coated with 0.3% and 0.6% of sodium alginate after 5 times of frying. The same behavior was appeared in K270 determination except there was decrement pat-tern in this criteria by increasing frying times especially from 5 to 7 times of frying in control and coated samples with 0.3% and 0.6% of carrageenan. The highest val-ue of refractive index of fried oil was in control sample followed by coated sample with 0.9% sodium alginate after 7 times of frying. However, the lower value was in coated sample with 0.6% carrageenan under the same conditions. It is cleared to know that, the viscosity of oil which used for frying control sample was lower than that of other treatments during various frying times. Data revealed that the color in-dex (oil deterioration) increase as the concentration of different edible coatings of beef steaks and number of frying increased.
Afficher plus [+] Moins [-]PHYSIOLOGICAL EXPLORATION OF CERTAIN MAIZE INBRED LINES AND HYBRIDS BY USING RAPID METHODS TECHNIQUE 1. GENOTYPIC DIFFERENCES
2005
M El-Koomy | A Abdel-Gawad | A. Abo-Shetaia | G Mahgoub
Identification of specific physiological differences among maize genotypes (six inbred lines, four single crosses and four three-way crosses) to drought would be useful to plant breeders for improving selection criteria. Two field experiments were conducted in optimum and stress moisture conditions at Gemmeiza Agricultural Re-search Station in 2001 and 2003 growing seasons. The treatments were 14 geno-types, (six inbreds and eight hybrids), which were separately established under three irrigation treatments in split plot design with four replications. The genotypes were compared under water-deficit conditions on the basis of certain rapid techniques to determine leaf area index (LAI), photosynthetic efficiency (photo), canopy tempera-ture depression (CTD), stomatal conductance (SC) and chlorophyll (CHL) content which were deleteriously affected by water stress in the sensitive genotypes. Results revealed that values of LAI, photosynthetic efficiency, canopy temperature depres-sion, stomatal conductance and chlorophyll content of maize hybrids surpassed those of inbred lines. This was true at 30, 45 and 60 days after planting (DAP). Dif-ferences among maize hybrids and among inbred lines were significant at different growth stages for the same studied traits, except of the LAI for the inbreds, at 30 DAP and CTD for the hybrids at 30 as well as 60 DAP. Detecting certain physio-logical criteria, i.e. LAI, photosynthetic efficiency (photo), canopy temperature de-pression (CTD), stomatal conductance (SC) and chlorophyll content (Chl) could be used as reliable techniques to explore the physiological activity of maize genotypes at early stages of growth and may be recommended in screening different genotypes in maize breeding programs.
Afficher plus [+] Moins [-]MINIMIZING THE TRANSPLANT DECAY DEVELOPMENT VIA CA APPLICATION AND MODIFIED ATMOSPHERE INCREASED STRAWBERRY YIELD
2005
A A-Alttif | A El-Gizawy | A Abd-Elhafez | M Omarah
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.
Afficher plus [+] Moins [-]INSECTICIDAL ACTIVITY AND BIOCHEMICAL STUDIES OF EGYPTIAN SESBAN, SESBANIA aegyptica ; JYNIT. SEED EXTRACTS AGAINST RICE WEEVIL, SITOPHILUS oryzae L.
2005
Salwa Ahmed | Nadra Al-Moajel
The toxic effective of wheat grains treated with Egyptian sesban, Sesbania ae-gyptica seed extracts offered to rice weevil, Sitophilus oryzae was determined. Chlo-roform extract was found to be the most effective. Reproductive potential of treated weevil were strongly affected as number of laid eggs was reduced and no progeny were obtained when adults were fed on wheat grains treated with either Lc50 or Lc95 . Extracts treatment with Lc95 of extracts gave protection up to 10 weeks for petrole-um ether, and 9 weeks for both chloroform and acetone extracts. All tested extracts reduced grain germination at the end of 14 weeks storage period. Treated wheat grains with Egyptian Sesban seed extracts reduced the weight loss of grains infested with the rice weevil. Biochemical studies show that some enzymes were affected in treated insects. S. aegyptica acetone extract was more effective than the other ex-tracts, in this affect, as it caused a significant reduction in amylase, trehalse and acid phosphatase activity. However, this extract caused an increase in invertase, alkaline phosphatase and cholinestrase activity.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]Impact of Organic, NPK and Biofertilization on Yield of Cowpea Cultivars Under Arid Land Conditions
2024
Dalia Soliman
This study was conducted to investigate the effects of organic, NPK, and biofertilizers on the yield of two cowpea varieties grown under arid land conditions. Two cultivars of cowpea (Karim-7 and Dokki-331) were evaluated using different fertilizer types. The fertilizers examined were organic (farmyard manure (FYM) and chicken manure (CHM)) and biofertilizers (effective microorganisms (EM1) and technology of smart fertilizer (TS)) in addition to NPK treatments (NPK (50 kg/fed), NPK (100 kg/fed), EM1 (15 m3.fed-1) + NPK (50 kg/fed), TS (15 m3.fed-1) + NPK (50 kg/fed). A randomized complete block design (RCBD) with 16 treatments and three replications was used to set up the experiment. The measured yield parameters were seed number/plant, pod length, seed number/pod, pod number/plant, dry yield/plant, dry yield/m2, bio yield, pod weight, 100-seed weight, and grain yield. The results cleared that the cultivar dokki-331 under EM1 biofertilizer + NPK (50 kg/fed) combination treatment was the superior practice for increasing all studied traits.
Afficher plus [+] Moins [-]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.
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