Main Stem Length Research Articles

Heliocarpus popayanensis Kunth (Malvaceae) tolera a hipoxia do substrato?

The species Heliocarpus popayanensis is used on floristic recomposition of degraded areas, wich’s soil might present hypoxy. Considering these aspects, this studies evaluates this species answers to flooding. Young plants were submitted to drained and flooded substract for 30 and 60 days, then flooded for 30 days and then drained for more 30 days. Main root and stem length, area and number of leaves, biomass and relative growth rate of roots, stems and leaves and the nutritional content of leaves were determined. Until 60 days of flooding there was a percentual reduction in biomass (38%), in RGR (77%) and in the area of leaves, including reduction in root and stem’s diameter (70%), and in the lignification of floematic cells. There was no anatomic alteration in leaves, but there was reduction of nutrients concentration (N, P, K, Fe, Cu, B). Therefore, young plants of the species Heliocarpus popayanensis survive to the flooding period considered above, probably due to anatomical and morphologic alterations. The rarity of this species in flooded area is probably related to other stages of the life cycle, such as seeds germination or competition with other species in the environment.

Abstracts of Nippon Dojo-Hiryogaku Zasshi

Abstracts of Nippon Dojo-Hiryogaku Zasshi

Promotion of shoot development and tuberisation in potato by expression of a chimaeric cytokinin synthesis gene at normal and elevated CO2 levels

The bacterial cytokinin biosynthesis gene ipt under control of a chalcone synthase promoter (PCHS) was introduced into potato (Solanum tuberosum L.). Two transgenic lines were selected for detailed study, because in these, root development was reduced only moderately, thus, enabling the plants to be grown in pots. Expression of the PCHS-ipt gene elevated the level of zeatin cytokinins markedly in the apical bud, subapical stems and leaves. The transgenic (IPT) plants exhibited a lower and denser leaf canopy relative to wild-type (WT) plants owing to reduction in main stem length, increase in node number per stem and promotion of lateral shoot development. Main stem diameter was increased markedly due to promotion of cell division associated with activation of cyclin-dependent kinase in the subapical stem. Expression of the PCHS-ipt gene induced aerial stolons, promoted growth of underground stolons and increased tuber number but reduced tuber weight and nitrogen content. The gene expression also increased pinnae and pinnule number per leaf, increased thickness of pinnae and promoted transpiration, photosynthesis and stomatal conductance – effects monitored by gas exchange and 18O and 13C analysis. The elevation of [CO2] to 900 μmol mol–1 promoted growth of both WT and IPT plants, ameliorated the negative effect of high cytokinin on tuber weight and interacted additively with ipt gene expression to promote stem growth.

EFFECT OF INDOLEACETIC ACID (IAA) AND BENZYLADININE (BA) ON GROWTH AND YIELD OF SOYBEAN (Glycine max (L.) Merril).

This investigation was carried out during the two successive seasons of 2006 and 2007 at the Agricultural Experimental and Research Station, Faculty of Agriculture, Cairo University Giza, Egypt. to study the effect of IAA and BA on vegetative growth and yield of soybean plant. Three concentrations, 50,100 and 200 ppm. were used of each growth regulator. The results revealed that IAA or BA increased main stem length, number of branches and leaves per plant, dry weight of leaves, stems and pods per plant, number of mature pods and seeds per plant and seed yield per plant. Number of main stem internodes, total leaf area per plant and weight of 100 seeds were not affected by treatment.

Stress gradients select for ecotype formation in Cicer judaicum Boiss., a wild relative of domesticated chickpea

The investigation of plant adaptive strategies has been enhanced by the advent of high resolution climate models facilitating greatly improved fine-scale habitat characterization. We have used this approach in the evaluation of C. judaicum Boiss., an annual wild relative of chickpea. 54 accessions from 12 Israeli populations representing three separate habitats differing in temperature and terminal drought stress intensity were evaluated in a common garden experiment, measuring phenology and growth. The results indicate that C. judaicum formed distinct ecotypes along environmental stress gradients, with stress avoidance as a key adaptive strategy: (1) germination is delayed with increasing collection site altitude and associated decreasing temperatures; (2) flowering date and productivity (as estimated by mainstem length) are inversely related to habitat stress, as defined by site climate or soil type. Populations from stressful sites escape drought stress through early flowering at the likely cost of biomass production. We conclude that precise habitat characterization facilitates the study of specific adaptation over relatively short geographic distances. This is particularly pertinent today because many of the key crop production system stresses (i.e., terminal drought, the impact of climate change) can be modelled climatically to identify potentially-adapted germplasm from ex situ and in situ collections.

Morphological characterization of Hungarian and Turkish watermelon (Citrullus lanatus (Thunb.) Matsum. et Nakai) genetic resources

Thirty-nine Hungarian accessions either collected from different regions of Hungary or obtained from gene banks and 11 Turkish accessions representing particular regions of Turkey were evaluated and compared for morphological characteristics. Qualitative characters were obtained according to the modified UPOV descriptor list for 58 characters. Sixteen quantitative characters (hypocotyl length, cotyledon width and length, length of main stem, number of nodes, length and width of leaf, length of petiole, length and width of the ovary, fruit weight, size of pistil scar, diameter and length of fruit, thickness of outer layer of pericarp, total soluble solids) were also measured. Results of both qualitative and quantitative measurements indicated that Hungarian and Turkish germplasm resources present a wide range of diversity for morphological traits. Accessions of the two countries show many similarities, therefore cannot be separated clearly. Considering the historical background, the two countries might have varieties with similar phenotypes and genetically common backgrounds.

RESISTANCE TO ROOT-KNOT NEMATODE, Meloidogyne incognita IN SOME CUCUMBER (Cucumis sativus, L.) INBRED LINES AND THEIR HYBRIDS

Three experiments were conducted in this study. The first experiment included two parts. In the first part, nineinbred lines and susceptible variety Beit alpha (control) belonging to cucumber (Cucumis sativus, L.) were evaluated for resistance to root-knot nematode, Meloidogyne incognita under greenhouse condition (artificial infestation). In the second part, the five inbred lines resistant, susceptible variety Beit alpha and their hybrids were evaluated for resistance to root-knot nematode, Meloidogyne incognita under greenhouse condition (artificial infestation). The second experiment included two parts. In the first part, nineinbred lines and susceptible variety Beit alpha (control) belonging to cucumber (Cucumis sativus L.) were evaluated for resistance to root - knot nematode, Meloidogyne incognita under field condition (natural infestation). In the second part, the five inbred lines resistant, susceptible variety Beit alpha and their hybrids were evaluated for resistance to root-knot nematode, Meloidogyne incognita under field condition (natural infestation). In the third experiment, the five hybrids and their parents were evaluated for some horticultural characters. The first experiment (pot test), in the first part only Line 7 and Line 8 evaluated were moderately resistant to root-knot nematode, M .incognita. L3, L6 and L9inbred lines evaluated were slightly resistant to M. incognita. Beit alpha (control) was susceptible to M. incognita in two parts. In the second part only the L7 × PC hybrid evaluated was highly resistant. The second experiment (field test), agreed with the first experiment (pot test) in all results except Line 7 evaluated was highly resistant to root-knot nematode ,(M. incognita). In the third experiment C. sativus line 6 was superior in vegetative characters and yield component. The hybrid L9 × PC was superior for main stem length and early and total yield as number and weight. L7 × PC hybrid was the highest in total yield and the best in fruit length. All hybrids were resistant to M. incognita and suitable for using in Egyptian agriculture.

Genetic variability and association studies of some quantitative characters in winter rapeseed (Brassica napus L.)

Information of the variability and the extent and type of relationship of some quantitative characters in rapeseed is important for an efficient breeding program. In addition, the association between seed yield and quality characters, oil and protein content, is of major interest. 10 winter rapeseed genotypes were evaluated for variation, genetic and phenotypic correlations and broad sense heritability for seed yield, yield and quality characters for 2 years. The results revealed significant differences for all yield and quality characters indicated the presence of sufficient genetic variability for effective selection. Variability, broad sense heritability, genetic advance were maximum for oil yield, seed yield followed by protein yield. In addition, very strong correlations were estimated among them. Simultaneous selection regarding seed yield would be an effective way to increase oil yield and protein yield. Plant height was associated with seed yield, oil yield, protein yield, number of pods on main stem and pod length. In conclusion, plant height, pod length, oil yield and protein yield were efficient characters as selection criteria.

Plant Growth and Mineral Element Content of Different Gourd Species and Watermelon under Salinity Stress

The watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] cultivar Crimson Tide and 7 different gourd genotypes [Cucurbita maxima, C. moschata, Luffa cylindrica, Benincasa hispida, Lagenaria siceraria landraces (Skp and Birecik), and L. siceraria hybrid (FRGold)] with rootstock potential for watermelon were grown under saline conditions (0, 4, 8, 12, and 16 dS m^{-1}) to investigate the responses of the gourd genotypes and watermelon to 30 days of salt stress. Plant main stem length, shoot dry weight, root dry weight, reduction in shoot dry weight, concentration of Na^+, Ca^{2+}, and K^+ in the leaves of the genotypes, and Ca^{2+}/Na^+ and K^+/Na^+ ratios were investigated. Plant length, and shoot and root dry weight of the plants significantly decreased as salinity stress increased. Gourd genotypes responded significantly differently to all investigated parameters under saline conditions. All genotypes had better growth performance than watermelon, except for L. cylindrica and B. hispida. The gourd genotypes and watermelon showed significant differences under saline conditions, with respect to ion regulation. Sodium concentration in the leaves of all the genotypes increased in response to salt application. There was a remarkable increase in Na^+ concentration in the leaves of L. cylindrica, whereas the lowest Na^+ concentration was observed in Birecik, and C. maxima, B. hispida, and L. cylindrica accumulated more Na^+ than watermelon and the other gourd genotypes did under saline conditions. Ca^{2+}/Na^+ and K^+/Na^+ ratios were significantly reduced by salt treatment and the degree of decrease was dependent on genotype. Genotypes with higher Ca^{2+}/Na^+ and K^+/Na^+ ratios produced more dry weight. Significant positive correlations were observed between plant biomass parameters, and Ca^{2+}/Na^+ and K^+/Na^+ ratios, whereas strong negative correlations were observed between Na^+ concentrations and shoot and root dry weight of the genotypes. Cucurbita and Lagenaria species were more tolerant to salinity stress than L. cylindrica, B. hispida, and watermelon.

RESPONSE OF SOME SWEET POTATO GENOTYPES TO A SLOW- RE-LEASE NITROGEN FERTILIZER UNDER ASSIUT CONDITIONS

This work was carried out during the two sum-mer seasons of 2006 and 2007 at Arab El-Awammer Research Station (A.R.C.); Assiut, Egypt, to study the effect of Enciabien as a slow- release fertilizer on sweet potato plants grown in newly reclaimed soil. Three genotypes of sweet potato ( two clones Assiut 201, 202 and one culti-var 17/8) and four levels of nitrogen i;e. 20 N units of ammonium sulphate (control ), 20 N units , 40 N units and 60 N units of Enciabien were used in the present study. The results indicated that applying 60 N units of Enciabien gave the best result in most of studied characters. Also, genotype Assiut 201 was the best genotype under the experiment condition for the most studied characters. The in-teraction between 60 N unit of Enciabien and culti-var 17/8 gave the highest averages of vine weight, main stem length and highest number of branch-es/plant, while the interaction between 40 N units of Enciabien and Assiut 201 gave the best number of marketable storage roots/plant, weight of mar-ketable storage roots/plant, total yield/fed and av-erage of root diameter. High dry matter content and high starch root percentage were obtained from genotype Assiut 201 when received any of four tested nitrogen levels. While, high percentage of fiber in sweet potato roots were obtained from the interaction between Assiut 202 and all levels of nitrogen. The highest percentage of sugar content in sweet potato roots was obtained from cultivar 17/8 when received any of four used N levels.

Citrus hybrid seedlings reduce initial time to flower when grafted onto shiikuwasha rootstock

The long juvenile period of citrus seedlings before flowering is one of the major obstacles in citrus breeding. Under the citrus breeding program of National Institute of Fruit Tree Science in Japan, 299 citrus hybrid seedlings were grafted onto shiikuwasha ( Citrus depressa HAYATA) and cultivated. Approximately one-third of the plants flowered two and a half years after grafting. The average length of the main stems of flowering plants was 308 cm, while that of non-flowering plants was 264 cm. Half of the plants having main stem length ≥300 cm formed flowers, while most of the plants having main stem length <210 cm formed no flower. These results indicate that plant vigor influences the flowering and that grafting effectively accelerated flowering. The proportion of flowering plants varied among cross combinations, ranging from 71.4% to 8.0% among the 10 cross combinations used.

Evaluation of Cultivar Differences in Preharvest Sprouting of Common Buckwheat (Fagopyrum esculentum Moench)

Preharvest sprouting of buckwheat (Fagopyrum esculentum Moench) is an important problem, but cultivar differences in preharvest sprouting and their causes have not been investigated. We detected cultivar differences under natural field conditions. Preharvest sprouting of three cultivars was significantly lower than that of the current main cultivar. Seeds collected before rainfall were threshed and incubated on a wet filter paper in a petri dish for 10 days at 10, 20, 30 and 40ºC in the dark, or at an alternating light and temperature condition of 8 h light at 30ºC and 16 h darkness at 20ºC. Germination was promoted by a higher temperature except for 40ºC, suggesting that the risk of preharvest sprouting in buckwheat is higher at a relatively higher temperature. The risk of preharvest sprouting in the field was highly correlated with germination at 20ºC (r = 0.98***) and 30ºC (r = 0.99***) in the dark, suggesting that germination test can be used to predict preharvest sprouting in the field. Preharvest sprouting was significantly correlated (r = −0.77**) with main stem length, suggesting that ecotype is partly responsible for this phenomenon.

Identification of quantitative trait loci influencing aerial morphogenesis in the model legume Medicago truncatula

In many legume crops, especially in forage legumes, aerial morphogenesis defined as growth and development of plant organs, is an essential trait as it determines plant and seed biomass as well as forage quality (protein concentration, dry matter digestibility). Medicago truncatula is a model species for legume crops. A set of 29 accessions of M. truncatula was evaluated for aerial morphogenetic traits. A recombinant inbred lines (RILs) mapping population was used for analysing quantitative variation in aerial morphogenetic traits and QTL detection. Genes described to be involved in aerial morphogenetic traits in other species were mapped to analyse co-location between QTLs and genes. A large variation was found for flowering date, morphology and dynamics of branch elongation among the 29 accessions and within the RILs population. Flowering date was negatively correlated to main stem and branch length. QTLs were detected for all traits, and each QTL explained from 5.2 to 59.2% of the phenotypic variation. A QTL explaining a large part of genetic variation for flowering date and branch growth was found on chromosome 7. The other chromosomes were also involved in the variation detected in several traits. Mapping of candidate genes indicates a co-location between a homologue of Constans gene or a flowering locus T (FT) gene and the QTL of flowering date on chromosome 7. Other candidate genes for several QTLs are described.

The Effect of Sulphur and Growth Regulators on Growth Characteristics and Grain Yield of Spring Sown Wheat

ABSTRACT During the year 1999, two field experiments (Experiments 1 and 2) were conducted at the University of Wales Aberystwyth U.K., to investigate the effects of soil and foliar applied sulphur (S) in wheat, in terms of its potential as a growth regulator and to compare the effects with that of commercial growth regulators, chlormequat (CC) and gibberellic acid (GA3). Foliar S (Thiovit 80% S) was applied to the spring wheat variety Axona at Zadoks growth stage (GS) 23 (tillering) in experiment 1, and at GS 30 and 32 (stem extension) in experiment 2. Treatments applied at GS 23 were: untreated control, micronized sulphur (Thiovit, 80% sulphur) at 10 kg/ha and 20 kg/ha, chlormequat (CC) at 2.5 L/ha and gibberellic acid (GA3) at 75 g/ha. Treatments applied in experiment 2 at GS 30 and 32 were similar apart from GA3, which was not included. In experiment 1 (applications at GS 23), grain yield was unaffected by the treatments applied, although both S and CC appeared to increase the number of ears at maturity. The internode lengths and the main stem-lengths were not affected with S application. In contrast, CC applications reduced all but the basal internode lengths, while GA3application increased internode lengths and overall stem length. In experiment 2 (applications at GS 30 and 32), the grain yield was again unaffected by S or CC. However, the stem length was reduced and the unit stem weight was increased following the application of S, though not to the same magnitude as with CC, and S at 20 kg/ha was more effective than S at 10 kg/ha. It was concluded that S, when applied at tillering (GS 23) in spring wheat, did not show potential as a growth regulator. However, when applied at the beginning of stem extension (GS 30 and 32), it did show potential to reduce the stem length and thereby increase the crops resistance to lodging. This is of particular relevance for use in low input, sustainable, and organic wheat production systems where the use of artificial plant growth regulators is discouraged or forbidden. Here, the use of foliar applied S as a potential stem shortener, coupled with its recognized fungicidal properties, make it an attractive and acceptable input.

Whole Plant Photosynthesis, Development, and Carbon Partitioning in Potato as a Function of Temperature

Knowledge of temperature effects on whole canopy photosynthesis, growth, and development of potato (Solanum tuberosum L.) is important for crop model development and evaluation. The objective of this study was to quantify the effects of temperature on canopy photosynthesis, development, growth, and partitioning of potato cv. Atlantic under elevated atmospheric CO2 concentration (700 μL L−1 CO2). Potato plants were grown in day‐lit plant growth chambers at six constant day/night temperatures, (12, 16, 20, 24, 28, and 32°C) during a 52‐d experimental period in 1999 in Beltsville, MD. Main stem length and main stem expanded leaf number were measured nondestructively at 4 d intervals while leaf, stem, root, and tuber weights were obtained by destructive harvesting at biweekly time intervals. Canopy level net photosynthesis (PN) was obtained from gas exchange measurements. The optimum temperature for canopy photosynthesis was 24°C early in the growth period and shifted to lower temperatures as the plants aged. Total end‐of‐season biomass was highest in the 20°C treatment. End‐of‐season tuber mass and the ratio of tuber to total biomass decreased with increasing temperature above 24°C. Accumulated biomass was a linear function of total C gain with a common slope for all treatments. However, the proportion of C allocated to tubers decreased with increasing temperatures. High respiration losses decreased total C gain at higher temperatures. When simulating photosynthesis and C assimilation in crop models, source–sink relationships with temperature and photosynthesis need to be accounted for.

Distribution and frequency of galls induced by Anisodiplosis waltheriae Maia (Diptera: Cecidomyiidae) on the invasive plant Waltheria indica L. (Sterculiaceae)

The frequency of galls induced by Anisodiplosis waltheriae Maia, a recently described species, on Waltheria indica L. was studied. W indica is an invasive weed in regeneration areas of Atlantic Forest in southeastern Brazil. Plants were collected in May 2004 and above-ground biomass, main stem length, number of leaves, number of galls per leaf and leaf area of each individual were recorded. Nearly 90% of all plants and 25% of all leaves were attacked by the gall midge, with an average of 0.67 galls/leaf. Leaf area had a weak effect on gall abundance while the number of leaves had no effect on gall abundance. Only 31% of the variation in gall abundance was explained by plant biomass. Natural enemies killed one third of the sampled galls. Predation accounted for 22.9% of gall mortality, unknown factors killed 7.6%, microhymenopteran parasitoids killed 2.5% and fungi only 1%. Mortality factors were not influenced by leaf area or gall density.

(256) Investigation into the Poor Seedling Establishment Trait Associated with Compact Phenotype in PI308916 and Possible Relationship to Apical Hook Formation

Cucumber PI308916 has a compact growth habit (short internodes and main stem length) due to a single recessive gene cp. We also observed that this PI has lower incidence of Phytophthora fruit rot, likely due to its upright fruit bearing habit. Previous researchers reported that compact cucumber lines derived from PI308916 exhibited the potential for higher yields due to increased planting density. Despite these potentially beneficial traits, efforts to develop PI308916-derived lines were terminated due to poor seedling establishment. The objective of this research is to determine the relationship between the compact phenotype and poor seedling establishment. Short internodes can be caused by deficiency in gibberellins or brassinosteroids that can also impact germination or apical hook formation, a trait important for seedling emergence from the soil. Germination rate and apical hook angle was recorded for `Wautoma' (control inbred line that forms normal apical hook), PI308916, and their F1, F2, and BC progeny. Germinating `Wautoma' seeds showed consistent, large apical hook angles (mean 147), while hook angles of PI308916 were broadly distributed from 0 to 180 (mean 96). F1 progeny for the reciprocal crosses had a similar angle (mean 134 and 133) to `Wautoma'. Segregation ratios for apical hook angle in the F2 and BC populations were consistent with a single recessive gene. Evaluation of the relationship between the apical hook and compact phenotype, showed an absence of the recombinant class of long internodes and small apical hook angle in the F2 population, suggesting that the two traits may be conferred by a single gene or two tightly linked genes.

Evaluation of Altered Cucumber Plant Architecture as a Means to Reduce Phytophthora capsici Disease Incidence on Cucumber Fruit

Fruit rot induced by Phytophthora capsici Leonian is an increasingly serious disease affecting pickling cucumber (Cucumis sativus L.) production in many parts of the United States. The absence of genetically resistant cultivars and rapid development of fungicide resistance makes it imperative to develop integrated disease management strategies. Cucumber fruit which come in direct contact with the soil-borne pathogen are usually located under the canopy where moist and warm conditions favor disease development. We sought to examine whether variations in plant architecture traits that influence canopy structure or fruit contact with the soil could make conditions less favorable for disease development. As an extreme test for whether an altered canopy could facilitate P. capsici control, we tested the effect of increased row spacing and trellis culture on disease occurrence in the pickling cucumber `Vlaspik'. Temperature under the canopy was lowest in trellis plots, intermediate in increased spacing plots, and highest in control plots. Disease occurrence in the trellis plots was significantly lower than in other treatments, indicating that preventing fruit contact with the soil reduced disease occurrence. The effect of currently available variation in plant architecture was tested using nearly-isogenic genotypes varying for indeterminate (De), determinate (de), standard leaf (LL), and little leaf (ll) traits. Plants with standard architecture had higher peak mid-day temperatures under the canopy and greater levels of P. capsici infection; however, levels of disease occurrence were high for all genotypes. Screening a collection of ≈150 diverse cucumber accessions identified to serve as a representative sample of the germplasm, revealed variation for an array of architectural traits including main stem length, internode length, leaf length and width, and number of branches; values for `Vlaspik' were in the middle of the distribution. Plant architectures that may allow for more open canopies, including reduced branching habit and compact growth, were tested for disease incidence. One of the compact lines (PI 308916), which had a tendency to hold young fruit off the ground, exhibited lower disease occurrence. The reduced disease occurrence was not due to genetic resistance, suggesting that architecture which allows less contact of fruit with the soil could be useful for P. capsici control for pickling cucumber.

Morphological and Nutritional Properties of Birdsfoot Trefoil (Lotus corniculatus L.) Autochthonous Populations in Serbia and Bosnia and Herzegovina

Birdsfoot trefoil (Lotus corniculatus L.) is a highly variable and widely distributed Old World perennial forage legume found in wild and naturalized populations throughout temperate regions of Europe, Asia Minor, North Africa, North and South America, Australia, and New Zealand. Understanding the relationships among birdsfoot trefoil morphological, ecogeographic and chemical characteristics may provide insights for better utilizing of exotic germplasms. Ten birdsfoot trefoil populations were and sampled and determined in Serbia and Bosnia and Herzegovina. Some morphological properties, such as growth form of populations, flower color, flowering period, number of stems, length of main stem, number of racemes per stem, number of flowers per inflorescence, number of pods per racemes, number of seeds per pods, hard seeds in the first year, dry matter (DM) yield, and some chemical properties, such as content of crude protein, ash, fat, crude fiber, phosphorus, calcium, magnesium, potassium, K/(Ca+Mg) ratio, and sulfur, manganese, iron, copper, zinc, selenium and tannin contents, were determined in all populations. Serbia is an important origin center of genes for many legume species. Considering the high values of their traits, some Serbian trefoil populations could serve as a valuable breeding material. In comparison with populations from other parts of the world, Serbian populations are superior in chemical properties and nutritional quality values. The investigated populations clustered in two distinct groups according to the analyzed characteristics.

Effect of Autumn Foliar Sprays with Nitrogen on Two Verities of Jujube ( Z. mauritiana and Z. spina-christi )

This study was conducted at the College of Agriculture , University of Baghdad / Abu-Ghraib during Autumn 2002 to study the effect of foliar sprays with three levels of nitrogen ( 0, 10, 20 gm / N / L) using Urea as a source for the nitrogen on varities of Jujube (Ziatuny and Tuffahi) while belong to the species Z. mauritiana and the other three varieties (Bambawi, Mallasii and Bathri) which belong to the species Z. spinachristi. البحث مستل من رسالة ماجستیر للباحث الثانی Randomized Complete Block Design were adapted with three replicate . The results can be summarized as follows: The Zaituny varity gave the highest stem length and diameter and the hargest angle between the stem and the branches and the highest percentage of dry weight and nitrogen content of leaves and the roots dry weights. Al-Batheri varity gave the highest branches on the mainstem, largest number of leaves and leaf area of the plant and the number and length of thorn. The Tufahi varity gave the lowest total area and the highest root length and diameter , while the highest leaf area was in Bambawi varity. Using 20 g / L nitrogen gave the highest length and diameter of main stem, number of branches on main stem, their length, angle width, number of leaves, leaf area, total leaf area per plant and highest length and diameter of main roots. The interaction between varities and fertilizer treatments have the significant effects on the studied characteristics.