Plant carotenoid derived β-ionone has been shown to have diverse biological effects on some insect herbivores and herbivore parasitoids. In this study, Arabidopsis transgenic plants over-expressing a carotenoid cleavage dioxygenase1 gene (AtCCD1) were generated to test whether β-ionone emissions could be enhanced and used to control feeding by the crucifer flea beetle (Phyllotreta cruciferae Goeze). The transgenic plants exhibited a morphological phenotype indistinguishable from the wild type (WT) control over their complete life cycle. Gas chromatography and mass spectrometry analyses of headspace volatiles collected from 6-wk-old intact flowering plants revealed substantially enhanced β-ionone emission from transgenic plants compared with WT, but no β-ionone enhancement occurred at a young vegetative stage (4-wk-old seedlings). Bioassays in an enclosed environment showed that AtCCD1 over-expression resulted in ≍50% less leaf area damage by flea beetles on transgenic plants compared with WT plants. The mean number of damaged transgenic leaves per plant also was significantly lower in transgenic plants (P<0.05). Our results indicate that AtCCD1 over-expression and induced β-ionone emission might find application in the control of pests for Brassica crops grown in greenhouse operations. Potentially, β-ionone also could be used on crops grown in open-air ecosystems if this allomone is released in sufficient quantities to discourage herbivore foragers.

Excess rainfalls may be the cause of waterlogging in soil, which affects the growth and development of wheat. Therefore, the objectives of this study were to examine the effects of waterlogging on shoot and root growth and physiological characteristics of wheat. Three experiments were conducted: experiment 1 (E1): evaluation of seedling growth on ten Iranian winter wheat varieties with waterlogging periods (1-4, 4-8, 8-12, and 12-16 days starting from seed germination). Seminal roots and plumule were investigated at seedling. The others are E2: pretreatment of waterlogging (15 days) at tillering and stem elongation stages and its effects on shoot and root growth at anthesis stage and experiment 3 (E3): pretreatment of waterlogging (15 days) at tillering and jointing stages and its effects on yield and yield components and also evaluation of stress tolerance indexes. The results of the seedling growth test (E1) showed that 1-4- and 4-8-day waterlogging severity reduced seminal root length (94.5 to 93.7 %) and plumule length (86.2 to 50.0 %) compared to control. Results of E2 indicated that waterlogging stress decreased shoot dry weight, root dry weight, total secondary root length, and chlorophyll a + b content of flag leaf by 28-31, 44-35, 20-31, and 28-35 %, respectively. Also, result of E3 showed that the grain yields of wheat varieties at two conditions of stress were different in base tolerance indexes. In general, the responses of wheat varieties to waterlogging were different at the three experiments. The varieties that had the most of dry weight and length of the root were tolerant. Thus, it is possible to use these characteristics as an index for selecting the varieties with tolerance to waterlogging.

growth rate and twinning rate are economic traits that can be used in goat breeding objectives. the aim of this study was to investigate polymorphisms in the insulin-like growth factor 1(IGF-I) and insulin-like growth factor binding protein (IGFBP-3) genes and their relationship with growth traits and twinning in Markhoz goats. Two sets of specific primers were used to amplify a 249bp fragment of IGF-I gene and a 316bp fragment of IGFBP-3 gene. pCr-ssCp analysis revealed three banding patterns for each gene that confirmed presence of a mutation in position 1617 of the IGF-I gene and a mutation in position 58 of IGFBP-3 gene. the genotype frequencies of IGF-I gene were 0.81 (gg), 0.16 (ga) and 0.03 (aa). also, the genotype frequencies of IGFBP-3 gene were 0.79 (TT), 0.17 (TC) and 0.04 (CC). The Odds Ratio estimated for twinning rate was 1.11 for second on first parity, 0.19 for third on first parity and 5.71 for second on third parity. The chi-square statistics were 6.46 for IGF-I gene and 3.32 for IGFBP-3 gene. the results also indicated that different genotypes of these genes had no significant effect on birth weight, weight at 6 months, at 9 months and at 12 months but the interactions between different genotypes of IGF-I and IGFBP-3 genes were significant for weaning weight and average daily gain from birth to weaning. These results suggest that twinning rate in markhoz breed is statistically affected by these genes and can be considered in breeding programs.

Carotenoids and sinapate esters in Brassica napus affect the nutritional value of the seed. In this study, the B. napus regulatory gene DE-ETIOLATED1 (DET1), which is a negative regulator of light-mediated responses in plants and affects carotenoid and flavonoid pathways in tomato, was suppressed both constitutively and in a seed-specific manner by RNAi. Constitutive silencing of DET1 resulted in transgenic seeds with substantially elevated levels of lutein, beta-carotene, and zeaxanthin relative to nontransgenic seeds. Levels of these carotenoids were also enhanced but to a lesser extent in seeds of transgenic plants with seed-specific silencing of DET1. Moreover, sinapate esters 1,2-disinapoylgentiobiose and 1,2-di-O-sinapoylglucose were identified in the seeds using 1D and 2D NMR, as well as ESI-MS spectrum analyses. The levels of 1,2-di-O-sinapoylglucose in seeds in both sets of transgenic plants were lower compared to nontransgenic seeds. The results revealed that DET1 suppression in B. napus can increase the levels of carotenoids and reduce the levels of sinapate esters simultaneously in the seeds, thus enhancing their overall nutritional value.

Stevia rebaudiana (Bert.) from Asteraceae family is a useful medicinal plant that prevents and cures diabetes, blood pressure, weight gain and tooth decay. Due to self-incompatibility in stevia, somatic embryo investigation for artificial seed production is valuable in this plant. In order to evaluate the callus induction characteristics in stevia, a factorial experiment was laid out based on a completely randomized design with three replications. The factors included ten hormone combinations and control, two kinds of media (MS and B5) and two types of explants (leaf and internode). Callus induction characters including the percentage of callus formation, days to callus induction, fresh and dry callus weight were recorded. Analysis of variance showed significant differences (p<0.01) among hormone combinations, media and explant types as well as their interactions. The best treatment for callus induction with minimum time to callus formation was 1 mg/l NAA+1 mg/l BAP. The highest fresh and dry callus weight were obtained on B5 medium supplemented by 1 mg/l 2,4-D+1 mg/l BAP (in leaf explant) and 0.25 mg/l 2,4-D+ 0.1 mg/l BAP (in internode explant). These results can be used in suspension culture. To induce somatic embryogenesis in suspension culture, six hormone treatments were investigated. The highest somatic embryogenesis percentage was obtained in MS medium supplemented by 2 mg/l 2,4-D+ 0.5 mg/l NAA+0.5 mg/l BAP.

We have developed an efficient transformation system for Tribulus terrestris L., an important medicinal plant, using Agrobacterium rhizogenes strains AR15834 and GMI9534 to generate hairy roots. Hairy roots were formed directly from the cut edges of leaf explants 10-14 days after inoculation with the Agrobacterium with highest frequency transformation being 49 %, which was achieved using Agrobacterium rhizogenes AR15834 on hormone-free MS medium after 28 days inoculation. PCR analysis showed that rolB genes of Ri plasmid of A. rhizogenes were integrated and expressed into the genome of transformed hairy roots. Isolated transgenic hairy roots grew rapidly on MS medium supplemented with indole-3-butyric acid. They showed characteristics of transformed roots such as fast growth and high lateral branching in comparison with untransformed roots. Isolated control and transgenic hairy roots grown in liquid medium containing IBA were analyzed to detect ß-carboline alkaloids by High Performance Thin Layer Chromatograghy (HPTLC).Harmine content was estimated to be 1.7 μg g −1 of the dried weight of transgenic hairy root cultures at the end of 50 days of culturing. The transformed roots induced by AR15834 strain, spontaneously, dedifferentiated as callus on MS medium without hormone. Optimum callus induction and shoot regeneration of transformed roots in vitro was achieved on MS medium containing 0.4 mg L −1 naphthaleneacetic acid and 2 mg L −1 6-benzylaminopurine (BAP) after 50 days. The main objective of this investigation was to establish hairy roots in this plant by using A. rhizogenes to synthesize secondary products at levels comparable to the wild-type roots.

The aim of the work was to evaluate the callus induction response and in vitro drought tolerance of eight genotypes of safflower. The experiment was laid out as a completely randomized design in a factorial arrangement with three replications. To evaluate the drought tolerance of the genotypes, growing calli were exposed to drought stress after two subcultures by adding different concentrations of mannitol to the culture medium for one month. Under stress conditions, the genotypes were compared in terms of proline content, cell viability, relative growth rate, ion content (Na+ and K+), relative water content and index of tolerance. Drought affected all the measured biochemical and physiological factors and there were significant differences between the tested genotypes. The proline content increased in drought-stressed calli, and mannitol, as a stress agent, stimulated the synthesis of proline in all the genotypes, especially at the highest concentration (505 mM), whereas the ion contents, cell viability, RWC, RGR and index of tolerance exhibited a significant decrease. This suggested that these biochemical and physiological traits could be used to predict the drought tolerance of safflower genotypes. The results indicated that the cultivars Isfahan and LRV-51-51 were more drought-tolerant under in vitro conditions than the other genotypes.

No abstract