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A NEW TECHNIQUE FOR GRAPE INSPECTION AND SORTING CLASSIFICATION
2006
Elbatawi I.E | M.T. Ebaid
Sorting and classification of fruits are the main problem specially for Superiorand King Ruby varieties which represent more than 50% of grape production inEgypt. A usual procedure to carry out this task is based on human visual inspectionconsidering general fruit attributes like color, size, shape, firmness and sugar contentof grape cluster. Color contains important information about fruit status and in somecases it is decisive for fruit quality differences. This paper provides a new techniqueto investigate the applicability of color classification, sugar content and firmness ofgrape. Standard RGB color chart, artificial neural network and a potential of nearinfrared(NIR) reflectance as a means for nondestructive measurements of grapefirmness and sugar content were used. NIR spectral data were collected from the twovarieties of grape in the spectral region between 800 nm and 1700 nm. Statisticalmodels were developed using the partial least square method to predict the firmnessand sugar content of grape. The models gave relatively good predictions of thefirmness of both Superior and King Ruby, with corresponding r values of 0.80 and0.65. The NIR models gave excellent prediction for grape sugar content with valuesof 0.71 % and 0.65 % Brix for Superior and King Ruby, respectively.
Mostrar más [+] Menos [-]EFFICIENCY OF HOST RESISTANCE AND FUNGICIDE APPLICATION FOR CONTROL OF POTATO LATE BLIGHT
2006
El-Shimy A.O. | Tomader, G. Abdel-Rahman
Late blight caused by Phytophthora infestans is one of the most destructive dis-eases potato in Egypt and world wide. Stability of resistance to late blight was eva-luated in twenty five potato cultivars during 2003 and 2004 successive seasons un-der heavy natural infection. Data showed that the potato cultivars Altesse, Occania, Safrane and Soleia highly resistant while cultivars Daisy, Hermine and Isabel rec-orded the highest susceptibility to late blight. Application different fungicide against potato late blight revealed that Aquagen Bro and Previcur-N were the best effective fungicides in reducing disease severity and progress of late blight. Data showed also that the losses of tubers due to late blight in season 2003 ranged from 11.75 Kg/plot (cultivar Hermes) to 18.0 Kg/plot (cultivar Lady Roseta) while in season 2004, yield losses ranged from 11.25 Kg/plot (cultivar Hermes) to 23.75 Kg/plot (cultivar Spun-ta). The results demonstrate that integration of Previcur-N treatment with host resis-tance was effective in reducing late blight and tuber yield loss of potato.
Mostrar más [+] Menos [-]ACTIVITY OF PEACH TWIG BORER Anarsia lineatella Zeller AND ITS ASSOCIATED BIO AGENTS ON PEACH TREES
2006
Salwa S.M. Abdel-Samad
The seasonal activity of the peach twig borer, Anarsia lineatella Zeller was in-vestigated during 2004 and 2005 seasons. The data revealed that the infested twigs empty from larvae (15%) were higher than that with larvae (1.25%) in February. The situation was reverse in April which recorded 8% and 14.75% for both, respec-tively. In fruits, infestation began to appear in the third week of March which rec-orded 2% whereas the maximum rate was recorded in May (16.75%). Three species of hymenopterous parasitoids were found; Apanteles ruficrus Haliday (Fam. Braco-nidae), Diplazon laetatorus Fab. (Fam. Ichneumonidae) and Microgaster tiro Rein-hard (Fam. Braconidae). These parasitoids reached its maximum during April (13.5%) that seems to be more active. Their numbers were positively correlated with the rate of infestation (r = + 0.799). In spite of presence of four predatory species (Coccinella undecimpunctata L., Rodalia cardinalis Mulsant, and Scymnus syriacus Marseul (Coleoptera: Coccinellidae) and Syrphus sp. (Diptera: Syrphidae)), it seems to be less active. Their numbers recorded very slight positive correlation with the rate of infestation (r =+0.423)
Mostrar más [+] Menos [-]RECOGNITION OF CERTAIN KAIROMONES BY THE PARASITOID TRICHOGRAMMA SPP. IN EGGS OF IT’S HOST CYDIA POMONELLA
2006
Sakr, H.E.A.
A kairomone from adult Cydia pomonella L. scales is an important factor in the host recognition and searching behaviour process of Trichogramma cacoeciae Mar-chal and Trichogramma dendrolimi Matsumura. The Trichogramma spp. used the chemicals from the host eggs for orientation to host and increased their parasitism. The females of T. cacoeciae*, T. dendrolimi** and T. dendrolimi*** contacted the unwashed host eggs significantly longer than the washed eggs. Washing the codling moth eggs with hexan significantly reduced the parasitism of all the tested Tricho-gramma strains compared to unwashed eggs. The treated apple trees with wing scales of C. pomonella had significant influence on the parasitism compared to un-treated trees. The percentage parasitism of codling moth eggs on the treated trees (31.6%) was significantly higher than on the untreated trees (19.3%).
Mostrar más [+] Menos [-]SUBCHRONIC TOXICITY OF MANCOZEB FUNGICIDE ON MALE WISTAR RATS: ULTRASTRUCTURAL ANALYSIS OF LIVER AND KIDNEY
2006
Madiha M. Talha | Kenawy M. | Salwa M. Abd-Allah
Dithiocarbamate mancozeb, an organometallic fungicide, was administered orally to male Wistar rats in two forms, pure technical 85% and formulated 80% WP, at sublethal doses of 125, 250 and 500 mg/kg b.w. for 28 days. Clinical chemical endpoints were measured after 2, 3, and 4 weeks of treatment initiation. Data disclosed that both compound formulations affected significantly serum enzyme activities particularly liver enzymes in a dose and time-dependent manner, compared with control. Such changes were accompanied with significant alterations in other parameters like; total protein, albumin, glucose, total lipids, triglycerides, cholestrol, urea, and creatinine. Furthermore, histological examination of liver and kidney showed several histopathogenic ubnormalities in the examined tissues of rats exposed to mancozeb either technical or formulated.
Mostrar más [+] Menos [-]ESTIMATES OF GENETIC COMPONENTS, PREDICTION AND GENETIC CORRELATION IN WHEAT (TRITICUM AESTIVUM,L.) USING NORTH CAROLINA DESIGN III
2006
Salama S.M | S.A . Awaad | Manal M. Salem
North Carolina Design III was used to estimate gene effects in bread wheat crosses. Twelve Egyptian bread wheat genotypes i.e. Sakha 69, Sakha 8, Gemmeiza 1, Gemmeiza 3, Gemmeiza 7, Giza 160, , Giza 162, Giza 164, Giza 165, Sids 1, Sids 3 and Sids 4, each was crossed back to testers, high performing (Gemmeiza 9) and low performing parent (Sakha 92) during three winter successive seasons i.e. 2002/2003, 2003/2004 and 2004/2005, to study; heading date (days) plant height (cm), flag leaf length (cm) flag leaf width (cm), flag leaf area (cm)2, extrusion length (cm), number of spikelets/spike, spike grain weight (g.), number of spikes/plant, number of grains/spike, 1000-grain weight (g.) and grain yield/plant (g.) characters. Results indicated that epistasis played great role in the inheritance of all studied characters except number of spikes/plant. Additive(D)and dominance(H) genetic variances were significant in all studied characters except number of spikes/plant and number of grains/spike. The additive genetic variance was more than dominance for heading date, plant height, flag leaf length, flag leaf width, extrusion length, spike length and 1000- grain weight. The ratio of (H./D) 0.5 was less than one for these characters but for the remaining characters the dominance genetic variance was more than additive. The values of(F) indicated that dominance was unidirectional for flag leaf length and flag leaf area, whereas it was ambidirectional for the remaining characters Prediction results revealed that it could be possible to derive reasonable proportion of new recombinants which are falling out side parental range for heading date, flag leaf length, flag leaf width, spike length, number of spikelets/spike, number of spikes/plant, 1000- grain weight and grain yield/plant. Genetic correlation indicated that additive, dominance and epistasis gene effects controlling grain yield/plant and spike grain weight, number of spikes/plant, number of grains/spike, 1000- grain weight, were signifant, suggesting common genetic pool or pleiotropy. Thus, selection based on additive genetic correlation indicated that indirect selection via, spike grain weight, number of spikes/plant, number of grains/spike and 1000- grain weight would be effective and enhance its importance as selection criteria .
Mostrar más [+] Menos [-]UTILIZATION OF COMBINING BIOTIC AND ABIOTIC TREATMENTS TO CONTROL BACTERIAL ANGULAR LEAF SPOT DISEASE OF CUCUMBER
2006
Wafaa Abd El-Sayed, M. | E.A.M . Gado | N.Y. Abd El-Ghafar
Bacterial angular leaf spot disease caused by Pseudomonas syringae pv. lachrymans is an important foliage disease of cucumber, under protected cultivation system. The present work was planned to control the disease using bio-agents and abiotic agents alone or combining, under greenhouse and commercial plastic house conditions. Data obtained indicated that application of bio- and abiotic agents decreased severity of bacterial angular leaf spot disease of cucumber, compared with the control. Fluorescent Pseudomonads (Pseudomonas aeruginosa, P. fluorescens and P. putida isolates) were more effectiveness than isolate of Bacillus subtilis to reduce the disease severity, when they were applied as soil drench treatment. Application of abiotic agents as foliar treatment was more effective than as seed treatment to decrease the disease severity. Isolates of P. fluorescens or P. putida as bio-agents and salicylic acid or ethephone as abiotic agents were the most effective against the disease. Disease severity was significantly reduced by increasing rates of abiotic agents. However, interaction between bio-agents (P. fluorescens or P. putida isolates) as soil treatment and abiotic agents (salicylic acid or ethephone) as foliar treatment greatly decreased severity of bacterial angular leaf spot disease of cucumber, under greenhouse and commercial plastic house condition, compared with the control. Combination between P fluorescens isolate as soil treatment and salicylic acid as foliar treatment were the most effective against the disease
Mostrar más [+] Menos [-]ROOT ROT DISEASE OF OLIVE TRANSPLANTS AND ITS BIOLOGICAL CONTROL
2006
M.S. Mousa, | M.K. Ali | A.A. Mosa | I.S Elewa
Several nurseries of olives in Fayoum and Giza were surveyed for root rot incidence during early summer of 2003. In Fayoum, root rot incidence reached 53% while in Giza, disease incidence was 44%. Disease symptoms consist of partial wilting, leaves browning and twig dieback, which was associated with severe root rot and basal stem cankers and followed, in most cases, by plant decline and death. The most frequently isolated fungi from rotted roots were Fusarium oxysporum, F. solani, F. moniliforme, Rhizoctonia solani, Sclerotium rolfsii, Cylindrocarpon sp. and Alternaria alternata. Isolation frequency of different fungi varied among olive cultivars. Generally, Fusarium spp. were the most frequently isolated pathogens and Fusarium oxysporum was the most frequent (35.5%) on all cultivars followed by F. solani (19.3%) R. solani (16.1%). Meanwhile, S. rolfsii, F. moniliforme, Cylindrocarpon sp. and A. alternata occurred at lowfrequencies. Pathogenicity tests showed that all tested isolates caused varied degrees of root rot symptoms on olive transplants, cvs. Manzanillo and Picual. Fusarium oxysporum, F. solani and R. solani caused the highest root rot incidence and severity on both cultivars. There was a positive correlation between disease severity on roots and severity of foliar symptoms. All evaluated olive cultivars were susceptible or extremely susceptible to fungal pathogens. All cultivars showed high disease severity with root rots, especially in response to infection by F. solani, F. oxysporum and S. rolfsii. However, the least foliar symptoms were recorded on cultivar Coratina. Application of two commercial biological control products (Rhizo-Plus and Trichoderma 2000) to soil, 24h before planting olive cuttings in the nursery, significantly reduced incidence of root rot on transplants of cultivars Manzanillo and Picual, up to 28 weeks after planting
Mostrar más [+] Menos [-]BIOLOGICAL CONTROL OF MELOIDOGYNE JAVANICA AND RHIZOCTONIA SOLANI ON SOYBEAN BY FORMULATION OF BACILLUS THURINGIENSIS AND TRICHODERMA HARZIANUM
2006
M.E Mahdy | E.Z Khalifa | Rania Z. El-Shennawy
Preparationof either Bacillus thuringiensis or Trichoderma harzianum were used as seed coating or soil application for management of root-knot and root rot disease complex caused by the root-knot nematode, Meloidogyne javanica and the fungus Rhizoctonia solani on soybean plants. Number of galls, root galling, egg masses and disease severity were reduced sharply on plants treated with both biocontrol agents, either as seed or soil application compared with non-treated plants. Soil application with both biocontrol agents was the best method in reducing nematode and fungus disease severity. Plant growth parameters i.e. fresh shoot and root weight, dry weight and number of pods and bacterial nodules were markedly increased with all treatments of biocontrol agent either with seed or soil treatment compared to plants grown in infested soil with either pathogens alone or combined. Results show that plant survival was more affected when R. solani was alone or combined with M. javanica. Seed coating was considered the effective method in increasing survival plants. The biochemical analysis of treated plants with both biocontrol agents were affected compared to non-treated plants grown in pathogen infested soil. The biochemical parameters i.e. chlorophyll A and B, carotein, phenols and amino acids were enhanced in bioagent treated plants compared to non-treated plants
Mostrar más [+] Menos [-]CERTAIN BIOLOGICAL ASPECTS, THRESHOLD OF DEVELOPMENT AND THERMAL UNITS FOR HYMENIA recurvalis (FAB.), (LEPIDOPTERA: PYRALLIDAE)
2006
Seham S.M. El-Gendi | F.F.M . Mostafa | F.A.E . Aly | S.H.A Hussein
Biological studies on the Hawaiian beet webworm, Hymenia recurvalis were carried out under laboratory conditions of 18.6 ± 2°C and 70 ± 5% R. H. The incubation period ranged between 5 and 7 days with a mean of 6.0 ± 0.3 days. The mean durations of larval, prepupal and pupal stages were 26.29 ± 0.3, 5.04 ± 0.08 and 16.86 ± 0.18 days, respectively. Mean adult longevities were 28.42 ± 1.80 and 26.08 ± 1.83 days, ranging between 19-41 and 15-37 days for female and male, respectively. The sex ratio was about 1 : 1.3 (♀ : ♂ ). Accumulative thermal units needed for certain biological features of H. recuurvalis were calculated and the estimated thermal thresholds were 10.97, 12.14, 10.49 and 13.55°C for egg, larval, pre – pupal and pupal stages, respectively. The corresponding values for the thermal units needed for development of these stages were 51.49, 168.47, 47.88 and 102.59 day degree at 25°C for the respective stages.
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