Horticulture and Crop Science

Collection of plant material was made from twenty four populations of Capparis spinosa that cover different geographical regions (North, Center, and South) of Jordan. Morphological characteristics of plants were measured and compared by analysis of variance and multivariate analysis methods. Analysis of variance showed that all of the characters in the examined ecotypes were significantly different (except plant width), showing high variability. Results showed that the differences noted in morphological characters in C. spinosa populations may be attributed to both genetical and environmental variations. Principal Component analysis reduced the original twelve morphological characters to five principal components. It was showed that the first five principal components explained 71.5% of the total variation, with number of the first order branch, branch length, diameter of first order branch, plant height and internnode length being the most important characters in the first principa...

The objective of the experiment was to evaluate the performance of four wheat cultivars under different levels of moisture and to identify certain mechanisms which can be used to screen for drought resistance. The durum cultivars, Hourani, Stork and Nascana and the spring wheat Pavon 76 were grown in the field under three levels of moisture stress: Rainfed conditions (R): supplementary irrigation (SI) and stress (5) imposed at 3 leaf stage. Moisture levels affected the traits studied with stress treatment significantly reducing biological, grain and straw yield, plant height and area of flag leaf. The cultivars differed in the traits studied. Though no interaction was observed between variety X moisture level, the local cultivar Hourani was more stable under the moisture levels tested. The semidwarf cultivar Stork produced the highest grain yield (3284 kg/ha) under supplementary irrigation and the yield was reduced by 35 % when exposed to the stress treatment. Under supplementary ir...

Two hundred and eighty six lines from tetraploid wheat (Triticum turgidum L. var. durum) landrace “SafraMa’an” were selected randomly during 1994-1995 growing season. The entire populations with three commercial check cultivars (Acsad 65, Hourani 27, and Amra) were evaluated at Maru Agriculture Research Station during 1995-1996 growing season for 16 characters including grain yield per plant. The objectives were to assess the magnitude of phenotypic variations for several traits in tetraploid wheat “SafraMa’an” and to evaluate the potential usefulness of some of the traits identiied. Results showed wide range of phenotypic variation for most characters. Mono-morphism was common for juvenile growth habit, whereas the rest of the characters exhibited polymorphism in varying degrees. Considering all characters, the average diversity (H′) for “SafraMa’an” landrace was 0.65 ± 0.047. There were 10 lines superior to best check (Hourani 27) for grain yield per plant. Subsequently, the popul...

Durum wheat is one of the most important staple food crops grown mainly in the Mediterranean region where its productivity is drastically affected by salinity. The study objectives were to identify markers associated with grain yield and its related traits under saline conditions. A population of 114 F8 recombinant inbred lines (RILs) was derived by single-seed descent from a cross between Belikh2 (salinity tolerant variety) and Omrabi5 (less salinity tolerant) was grown under non-saline and saline conditions in a glasshouse. Phenotypic data of the RILs and parental lines were measured for ifteen agronomic traits. Association of 48 SSR loci covering all 14 chromosomes with ifteen agronomic traits was analyzed with a mixed linear model. A total of 28 SSR loci were signiicantly associated with these traits. Under saline condition, 13 markers were associated with phenological traits while 19 markers were associated with yield and yield components. Marker alleles from Belikh2 were assoc...

Comparing the effects of salinity on durum wheat cultivars differing in their salt tolerance is of interest to physiologists investigating traits associated with adaptation to saline conditions and to breeders to develop cultivars for salt infected areas.This study was conducted to determine the effects of salinity on germination percentage, seedling growth, yield components, and physiological traits of two improved durum wheat cultivars (Triticum turgidum var. durum) developed by ICARDA durum breeding program namely, Belikh2 and Omrabi5. Plants were grown in greenhouse in sand cultures and irrigated with Hoagland's solution. Six salinity treatments were imposed by NaCl to the base nutrient solution. The treatments were 50, 100, 150, 200, 250, and 300 mM NaCl, along with a control treatment. Germination percentage and seedling growth were tested for both cultivars at the same mentioned treatments using a growth chamber. Germination percentage, seedling growth, vegetative growth,...

Caper bush is grown commercially to obtain unopened flower buds (capers) used as a condiment in salads and sauces and in the manufacture of cosmetics and medicines. Capers play an important role in the food industry and have become a costly and a commercially valuable product. The effect of various treatments on the behavior of in vitro consecutive micropropagation stages of Capparis spinosa was studied and a micropropagation protocol was developed. Many media were tested; Murashige and Skoog (MS) at different basal salt strengths, modified MS (1⁄2MSD) and woody plant medium (WPM) for the establishment stage. WPM was found to be the best medium for establishment of mother plants. Multiple shoots were obtained on WPM medium supplemented with 0.8 mgL kinetin in combination with 0.05 mgL indole-3-butyric acid and 0.1 mgL gibberellic acid. High frequency (80%) of rooting was obtained on 1⁄2MS medium supplemented with 5 mgL indole-3-acetic acid. Regenerated plantlets were successfully ac...

Twenty-one locations scattered over eight provinces in Jordan were surveyed to assess the ecogeographical distribution of wild Arum species. Twenty-six morphological traits were measured on the collected species and populations to study the phenotypic ...

Arum is a wild herbaceous tuberous perennial plant belonging to the Araceae family. So far, there is no report published in Jordan about the application of molecular markers to characterize wild Arum plant. This study was initiated to assess levels of genetic variation of this plant using molecular markers. Twenty one locations were surveyed to assess the genetic variation in this plant. Ten plants from each location were collected and measured directly in the field. In total, 210 plants were studied and three species were found in the 21 locations. Amplified fragment length polymorphism (AFLP) technique was used to study the genetic variation among Arum species. Six combinations of selective primers were generating a total of 2882 reproducible and clearly scorable bands of different sizes; 98.6% of them were polymorphic. Genetic distance was constructed based on Nei dissimilarity coefficient. The overall genetic distance between Arum species was 25%. The results showed that Arum po...

Eleven SSR primers were used to analyze 56 accessions of durum wheat consisting of 29 wheat-like accessions, 12 black glumes white awned, 12 white glumes black awned accessions and three local landraces in order to assess natural hybridization of cultivated wheat with its wild progenitor Triticum turgidum ssp. dicoccoides and to search for evidence of the introgression of wild relatives genes into durum wheat. A total of 738 bands were scored across the accessions. Of the 24 genomic loci totally assayed, 20 (83%) were found to be polymorphic and the remaining four monomorphic. The white glumes black awned accessions were completely separated in one cluster, whereas the black glumes white awned were grouped with wheat-like accessions in the main and its sub-clusters using UPGMA analysis. A total of 560 markers were scored for both wheat and black glumes white awned accessions in which 70% of genomic loci showed to be polymorphic. This high occurrence of polymorphism was most likely a...

The NAC family is a multigene family that present uniquely in plants and whose members are involved in many important cellular processes including abiotic stress tolerance. In this study, sequences of two ATNAC3-related genes (SlNAC3) were identified in the tomato genome using different bioinformatics approaches. Phylogenetic analysis clustered 84 tomato identified NAC proteins into 19 different subfamilies that included 5 subfamilies for stress-related NAC genes with SlNAC3 members clustered with previously characterized ATNAC3 members from Arabidopsis. Gene expression analysis of SlNAC3 genes indicated that both of them are expressed in response to drought and salinity stress conditions. The over-expression of two stress-related SlNAC3 in tomato plants resulted in enhanced drought and salt tolerance when compared with wild type plants. The identified stress-related NAC genes could be a useful tool to improve tomato productivity under stress conditions.

In this study, fodder barley was irrigated with pure tertiary treated sewage effluent (TTSE) and TTSE mixed with different amounts of tap water (20, 40, 60, and 80% tap water) using pure tap water as a check in a hydroponic system. The objective was to evaluate the effect of TTSE on heavy metals content (Pb, Cd and Ni) in barley biomass and some other nutrient elements (N, P, K, Ca and Fe). All these elements were present in much higher concentrations in TTSE compared to tap water. Heavy metal concentrations in barley biomass increased with an increase in the concentration of TTSE. Cadmium levels ranged between 0.06 (barley grown in tap water) and 0.1 ppm for barley grown in pure TTSE. These figures are lower than the limits set by the Commission of the European Union and WHO. Lead levels in biomass also increased with an increase in TTSE level. Ranging between 0.33 (tap water) to 0.7 (TTSE) ppm on dry weight basis, these levels are within acceptable limits for fodder. Nickel concentrations in barley biomass ranged between 6 (tap water) and 9 (TTSE) ppm. The toxic or excessive nickel concentrations in mature leaf tissue ranged between 10 to 100 ppm. The concentrations of N, P, K, Ca and Fe in barley biomass were within normal limits. The study revealed that fodder barley grown hydroponically could be irrigated safely with TTSE, as a useful alternative disposal method of waste water without the risk of accumulation of heavy metals in the soil.