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Morphological ontogeny and molecular analyses of geographic strains of two closely related Neoseiulus species (Acari: Phytoseiidae)

Research Abstract

The predatory mites, Neoseiulus longispinosus (Evans) and N. womersleyi (Schicha) (Phytoseiidae) are two morphologically close species. Although they can be mainly separated by the length of the dorsal seta S5, misidentifications may occur. The present study investigated various strains of the two closely related species collected from Japan, Taiwan and/or Thailand using a combination of morphological and molecular data. We described and illustrated the adults and immature stages. We also sequenced the 28S region of nuclear ribosomal DNA to determine whether these strains represent different species. The two species could be clearly separated based on the length of seta S5 and the ratio of setae Z5/S5. In a 28S tree, the examined strains also formed separate clades with 100% bootstrap values. We conclude that a combination of different methods is often necessary to precisely distinguish these closely related taxa.

Research Authors
Negm MW, Matsuda T, Kayukawa T, Ho C-C, Hsu Y-T, Kongchuensin M, Konvipasruang P & Gotoh T.
Research Date
Research Department
Research Image
Populations of Neoseiulus species examined in the present study
Research Journal
Acarologia
Research Member
Research Year
2021

EFFECT OF PLANT DENSITY ON ONION GROWN BY SETS UNDER ASSUIT CONDITIONS

Research Abstract

The objective of  this study was to determine the plant density  that result in the best marketable yields and gross crop value per fedan of onion Giza 6 cv. that grown   by sets .Sets were grown at the Experimental Farm of the Faculty of Agriculture, Assuit University, Assuit on September 13 and 15 in 2007/2008 and 2008/2009 seasons, respectively. Sets were grown on rows of 3.5 m long and 50 cm wide. Three rows were included each plot. Sets were grown at 4, 6 and 8 cm between plants (175,116 and 87 plants when sets grown on two sides of row and  262,175and131 plants when sets grown on three sides of row). Results showed  that  , plants gave the smallest bulb diameter when sets were grown at 4 cm space(high density) .The largest space between plants (low density) ,the highest value for both percentage of bolters and doubles were. The highest value of marketable yield was obtained when sets grown at 4 and 6 cm (262 and 175 plants/ row) and on 3 sides per row .Maximum economic returns occurred at higher plant populations.  High incidence of double onions was closely related to low onion plant population. Doubles clearly decreased with increased plant density. Wide plant spacing reduced onion bulb yield, but it significantly increased individual bulb weight and bulb diameter.

Research Authors
Shreen Y. Attallah; M. H. Zein El-Abedin
Research Date
Research Department
Research Journal
J.of plant production
Research Member
Research Pages
487-492
Research Vol
3
Research Year
2012

Yield and Quality of Onion Sets as Affected by Seeding Rate and Planting Date under Assiut

Research Abstract

Field experiment were carried out on the clay soil of the Experimental Farm, Faculty of Agriculture, Assiut University,Assiut in two consecutive  winter seasons 2007-2008 and 2008 -2009.The aim of this investigation was to study the effects of three planting dates and three seeding rates in cv. Giza 6 on yield and quality of onion sets un- der Assiut conditions. The obtained results indicated that the onion plants. Average bulb diameter increased significantly with earlier planting compared with later planting. Lower seeding rate gave significantly the biggest average bulb diameter. The authenticity bulb was obtained from planting on December 1st in the second sampling date (105 days).However, no true bulb was obtained from any planting date in the first sampling date (75 days)in both seasons. Lower seed rate (30 kg/feddan) significantly gave the truth bulb in both seasons.

Research Authors
Rania G.Mohamed,Mohamed M.Abdalla,Hammam Z.EL-Dekashey and S.Y.Attallah
Research Date
Research Department
Research Pages
27-47
Research Vol
43(1)
Research Year
2012

Magnetic Water and chemical Substances Impact on Growth Parameters and Yield Components of Onion Crop under Assuit Conditions

Research Abstract

The experiments of this study were conducted to investigate the effect of magnetized water and two other chemical substances that are kown as Agro promotor1 (substance No.48) and Agro promotor2 (substance No.50) on growth, yield and chemical composition of onion variety Giza 6.  These substances were obtained from Cairo University. Result revealed that growth parameters, yield and its component and chemical contents increased with using both of magnetic water and Agro promotor1 (substance No.48) at concentration of 3 ml/l comparing with control (untreated) treatment. Using magnetized water and Agro promotor1 (substance No.48) at concentration of 3 ml/l induced positive significant effect on plant height and weight, number of leaves/plant and bulb diameter as well as significantly improved neck and bulb diameters, bulb weight, total soluble soiled, total yield and marketable yield percentage than plants of control treatment which showed an increase in percentage of bolters, in both season. In general, it might be concluded that application of each of magnetized water and Agro promotor1 (substance No.48) treatments proved to be good technology to enhance growth, yield and quality when compare with untreated treatment. The marketable yield was increased by 30% as compared with control treatment by using magnetized water and increased by 22-235% when substance No.48 at concentration of 3 ml/l was used. The increase in total yield ranged from 12-15.4% when using magnetized water and was 14-15.4% when substance No.48 at concentration of 3 ml/l compared with control treatment. This study recommends using magnetized water to obtain the highest marketable yield and the lowest percentage of bolters. In case of magnetized water un-available, Agro promotor1 (substance No.48) at concentration of 3 ml/l can be applied.    

Research Authors
S.Y.Attallah
Research Date
Research Department
Research File
Research Journal
Assiut.J of.Agric.
Research Member
Research Year
2017

Seed Chilling Enhances Head Earliness and Yield of Artichoke (Cynara scolymus L.) under Assiut Conditions

Research Abstract

Subjection of seeds to a chilling pretreatment has been reported to enhance crop yield particularly earliness in number of vegetable crops including seed-grown (annual) globe artichoke.  Therefore, the current study was carried out to assess the impact of seed chilling pretreatment on the production of seed-propagated globe artichoke in two cultivars (EL-Balady and Chinese) under Assiut conditions. Four seed pretreatments were utilized. These were seeds imbibed in water for 24 h and subjected to chilling at 4-5 0 C for 0 (positive control), 10 and 15 d, in addition to untreated seeds (negative control). These seed pretreatments were scheduled so as to be simultaneously ready at the time of sowing. A field experiment was carried out to test these treatments during 2014/2015 and 2015/2016 winter seasons at the Experimental Farm of Faculty

of Agriculture, Assiut University, Assiut, Egypt. Data revealed an influential effect for seed chilling on growth, earliness and yield of artichoke. Comparing to plants of both control treatments, imbibed seeds which were subjected to chilling at 4-5˚ C for 15 d gave the greatest reduction in number of days to form heads and highest early head yield. Average head weight, number of heads/plant and head diameter and height were increased while total yield was elevated. This pre-sowing seed chilling treatments increased yield by 22.5% and 40.3% relative to positive and negative controls, respectively, on average. The reduction in the number of days to develop harvestable inflorescences ranged from 21 d to 23 d comparing with the positive and negative controls, respectively, on average. Apparently, seed chilling pretreatment may be usefully applied to overcome the delay in head formation, due to insufficient natural chilling under Assiut conditions, while elevating total head yield and expanding production season

Research Authors
S.Y.Attallah
Research Date
Research Department
Research Journal
Assiut.J.Agric.
Research Member
Research Vol
48(1)
Research Year
2017
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