دراسات على تطور الجنين والتهجين بين اليوسفي البلدي واليوسفي الكليمانتين

STUDY ON EMBRYO DEVELOPMENT AND HYBRIDIZATION BETWEEN BALADY AND CLEMENTINE MANDARINS
By
Abd El-Fattah Montasir Abd El-Salam Khedr

Abstract

This study was carried out during 2004/2005 season and 2005/2006 season on two cultivars of mandarin, Balady(Local)mandarin (Citrus reticulata) and Clementine mandarin(Citrus clementina Blanco) at a private orchard located at Gharbia Governorate to improve some characteristics of Balady mandarin through the hybridization with Clementine mandarin and study the effect of hybridization on fruit set, fruit retention, number of seed per fruit and germination percentage. Study the stages of embryo development in Balady mandarin to know the dates of nucellar embryo initiation through taking samples on stable dates after pollination (3 days) for five months and make some anatomical studies. A primary determination on the morphological characters was carried out for the seedlings from hybridization between Balady and Clementine mandarins under plastic house and orchard conditions such as seedling height, branches number, Leaves number and Leaf area.
The results confirmed that the final fruit set % in 2005-2006 season was 4.6% while in 2006-2007 season, the final fruit set was 4.9 %.
Germination percentage data in 2005/2006 season showed that the germination commenced after 26 days after planting under plastic house conditions .The accumulated seed germination number for 2005/2006 season was 38 , while in 2006/2007 season was 56.
There was a variability in the morphological characteristics of seedlings under the plastic house and the field conditions. The noticed differences in the seedling heights, leaves number and branches number under plastic house conditions as well as under field conditions indicate that there is a possibility of being due to genetic factors beside the environmental conditions. Also, there was variation in leaf area between seedlings from the hybridization between Balady and Clementine mandarin, such variations indicate differences abilities of the trees for the photosynthesis process, consequently sexual other growth and developmental factors will be affected.
Moreover, anatomical studies indicated that the nucellar embryo initiated in early stages of embryo development. However, it was found that the sexual embryo has a suspensor, while this is not present in the nucellar embryos. Thus this could be used as sign to select and separate the sexual embryo under the microscope and growing it under tissue culture condition to complete its growth and obtain hybrid seedlings.

دراسات على التهجين بين بعض أصناف الخوخ

STUDIES ON HYBRIDIZATION BETWEEN SOME
PEACH VARIETIES
By
Mohamed Saad Ahmed Saad Gawish

Abstract

This work has been carried out during the 2006/2007and 2007/2008 seasons on 20 trees of the five peach (Prunus persica. (L.). varieties: Florda prince, Desert red, Sahrawy, Soltany and Meet Ghamr local selection..
Breeding experiment had been carried out between some selected peach varieties that are growing on a large scale in Egypt. This aimed to produce some peach selections that have superior quality under Egyptian condition as well as wide range of adaptability.
Dates of flowering, full blooming and maturity of parents were noted. The selected trees were vigorous, free from any pathogenic symptoms, and subjected to the ordinary horticulture practices.
The vegetative and fruit quality of the hybrid seedlings have been evaluated and the results could be summarized as follows:

The evolution is made that, there are some encouraging possibilities in the produced fruits of the hybrid seedlings, as the case of having a nectarine types on one of the seedlings and a non-melting flesh, large size and rather sweet and very acceptable taste on another. However, it is too early to give any conclusion in the time being before these hybrids are evaluated completely.

دراسات فسيولوجية على بعض اشجار وشجيرات الزينة
PHYSIOLOGICAL STUDIES
ON SOME ORNAMENTAL TREES AND SHRUBS
By
Mohamed Refaat Ibrahim Magouz

Abstract

This study was carried out at the Experimental Farm of the Faculty of Agriculture, Kafr El-Sheikh University during two successive seasons (2006 and 2007). This study included two experiments in each season. The first experiment aiming to study the effect of soil salinity (sodium chloride and calcium chloride mixture at ratio of 1: 1 by weight at the concentrations of 0.0, 0.4, 0.8, 1.2 and 1.6 g salt/100 g soil) and paclobutrazol at 0, 25, 50 and 75 ppm on the growth and chemical constituents of Hibiscus rosa-sinensis L. transplants. Foliar application of a paclobutrazol added at two times, the first one was done on May 15th and repeated again after 30 days in early morning. The second experiment was to study effect of three levels of nitrogen (3, 6 and 9 g N/plant added in two equal doses on April 15th and May 15th) and sulphur (added in one dose on April 15th at the rates of 1, 2 and 3 g S/plant) on the growth and chemical constituents of Hibiscus rosa-sinensis, L., Lantana camara, L. and Citharexylum quadrangulare, J. transplants. The obtained results could be summarized as follows :
First experiment :
Salinity treatments markedly reduced growth characters in Hibiscus rosa-sinensis, Linn. plants, when compared to the control. The control and 0.4% NaCl + CaCl2 (1: 1) mixture salts treatment produced the highest values of survival percentage, plant height, number of branches and roots/plant, stem diameter, root length and fresh and dry weight of vegetative parts and roots. All salinity levels markedly increased Na+ and Ca++ percentages and decreased Chlorophyll (a and b) content, N, P and K percentages in the leaves of Hibiscus rosa-sinensis, L. compared to the control. Increasing NaCl + CaCl2 (1: 1) mixture more than 1.2% was lethal to Hibiscus transplants. Paclobutrazol generally improved vegetative growth and roots parameters. However, spray of paclobutrazol at high rate (75 ppm) had the most pronounced effect on growth of Hibiscus rosa-sinensis L. transplants in the majority of treatments. The data suggested that paclobutrazol promoted salt stress avoidance of Hibiscus rosa-sinensis, L. plants by reducing the accumulation of harmful Na+ and Ca++ ions in the leaves of plants and improved N, P and K absorption.
Second experiment:
All nitrogen and sulphur application levels significantly increased the most vegetative growth parameters (plant height, root length, number of branches and roots /plant, stem diameter and fresh and dry weight of vegetative parts and roots ) over the control of Hibiscus rosa-sinensis, L., Lantana camara, L. and Citharexylum quadrangulare transplants. Using nitrogen and sulphur at high level (9 g N and 3 g S/plant) had the greatest effect for increasing all vegetative growth and roots parameters of the three plants compared to control. All nitrogen and sulphur application levels increased chlorophyll (a), (b) contents, N, P and K% in the leaves over the control of the three plants. However the highest values resulted from using high level (9 g N and 3 g S/plant) in the two seasons.

استجابة الفلفل الحلو للتسميد العضوي والمعدني وبعض معاملات التقليم
تحت الصوب البلاستيكية

RESPONSE OF SWEET PEPPER TO ORGANIC AND MINERAL FERTILIZATION AND SOME PRUNING TREATMENTS
UNDER PLASTIC
By
Adel Abo-AlAsad Mohamad Fayed

Abstract

The experiments were carried out at Sakha Protected Cultivation Center, Ministry of Agriculture Kafr El-Sheikh governorate during the winter season of 2006 /07 and 2007 /08 on "Titanic" sweet pepper hybrid under unheated plastic house. The aim of this study was to investigate the effect of fertilizer source and plant pruning on vegetative growth, flowering, yield and fruit quality as well as chemical analysis of plant and soil biological activity. The results can be summarized as follows:
Application of mineral fertilizer gave the highest values of vegetative growth parameters (plant height, number of leaves / plant, stem diameter and leaf area), flowering and fruiting (number of flowers and fruit / plant), yield (early and total yield and marketable fruits), fruit quality (fruit length, diameter, S.S.C% and nitrate content), while organic treatment increased ascorbic acid content and soil biological activity.
All pruning treatments increased plant height, leaf area and decrease number of leaves, stem diameter and fruit yield / plant (early and total), while pruned plants to one shoot spacing 25 cm increased number of marketable fruit / m2. Fruit quality and leaf mineral content were not significantly affected by pruning treatments.
The combination interaction between fertilizer sources and pruning treatments had no significant effect on most of vegetative growth parameters, flowering, yield and fruit quality. While unpruned plants fertilized by organic fertilizer gave the highest biological activity compared to other combination treatments in both seasons.

دراسات فسيولوجية على تشقق ثمار البرتقال
PHYSIOLOGICAL STUDIES ON ORANGE FRUIT SPLITTING
By
Fayed Abd EL Hameed El Sammak

Abstract

The study included data on the effect of two growing sites namely, Kafrelshiekh and Elbehera where the trees of Washington Navel orange are grown on two different rootstocks namely, Sour Orange and Volkamer lemon.The obtained data on the effects of two rootstocks under the agro-climatic condition of the two localities on fruit splitting were combined in one experiment in two successive seasons of 2005/2006 and 2006/2007.
The study indicated that fruit splitting starts early when the fruits are green, reaching a maximum in September . there are a positive relationship between fruit splitting and each of peel thickness, fruit and navel size, crop load, high air temperature and relative humidity under the agro-climatic conditions of the two localities. Fruit splitting was higher at Elbehera on Sour Orange than on Volkamer Lemon rootstock at Kafrelshiekh .Peel analysis recorded a reduction in Ca and Mg concentrations in the peel of splitted fruits and this reduction may be responsible for increasing splitting .In this respect, Volkamer Lemon rootstock was superior than Sour Orange rootstock to minimize fruit splitting .Also, fruit splitting was higher in the southern aspect, interior the tree and in the lower part of the tree canopy.
The study also included results and discussions on fruit growth in relation to air temperature and relative humidity. The obtained results indicated that both of high temperatures and relative humidity during the period of cell enlargement and the used rootstock are involved in the splitting problem in Washington Navel orange fruit.