The indole-3-acetic acid (IAA) content of developing grains of Oryza sativa subsp. japonica was measured by combined liquid chromatography, tandem mass spectrometry in multiple-reaction-monitoring mode. The increase from 50 ng g(-1) fresh weight to 2.9 µg g(-1) fresh weight from 1 to 14 days after pollination was much larger than that previously reported by enzyme-linked immunoassay methods. The largest increase in IAA content coincided with the start of the major starch deposition phase of grain-fill. The increase in IAA content was strongly correlated with the expression of putative IAA biosynthesis genes, OsYUC9, OsYUC11 and OsTAR1, measured by quantitative reverse transcriptase polymerase chain reaction. These results confirm the importance of the tryptophan aminotransferase/YUCCA pathway in this system. All three genes were expressed in endosperm; expression of OsYUC11 appeared to be confined to endosperm tissue. Phylogenetic analysis indicated that OsYUC11 and AtYUC10 belong to a separate clade of YUCCAs, which do not have orthologues outside the Angiosperms. This clade may have evolved with a specific role in endosperm. Expression of tryptophan decarboxylase in developing rice grains did not correlate with IAA levels, indicating that tryptamine is unlikely to be important for IAA synthesis in this system. In light of these observations, we hypothesize that IAA production in developing rice grains is controlled via expression of OsTAR1, OsYUC9, OsYUC11 and that IAA may be important during starch deposition in addition to its previously suggested role early in grain development.

Indole-3-acetic acid (IAA) synthesis is required for grain-fill in maize and appears to be regulated by cell-wall invertase (CWIN) activity. OsYUC12 is one of three IAA biosynthesis genes we previously reported as expressed during early rice grain development, correlating with a large increase in IAA content of the grain. This work aimed to investigate further the role of OsYUC12 and its relationship to CWIN activity and invertase inhibitors (INVINH). The analysis shows a brief peak of OsYUC12 expression early in endosperm development. Meta-analysis of microarray data, confirmed by quantitative expression analysis, revealed that OsYUC12 is coexpressed with OsIAA29, which encodes an unusual AUX/IAA transcription factor previously reported as poorly expressed. Maximum expression of OsYUC12 and OsIAA29 coincided with maximum CWIN activity, but also with a peak in INVINH expression. Unlike ZmYUC1, OsYUC12 expression is not reduced in the rice CWIN mutant, gif1. Several reports have investigated CWIN expression in rice grains but none has reported on expression of INVINH in this species. We show that rice has 54 genes encoding putative invertase/pectin methylesterase inhibitors, seven of which are expressed exclusively during grain development. Our results suggest a more complex relationship between IAA, CWIN, and INVINH than previously proposed.

Plant proteome databases were mined for a flavin monooxygenase (YUCCA), tryptophan decarboxylase (TDC), nitrilase (NIT), and aldehyde oxidase (AO) enzymes that could be involved in the tryptophan-dependent pathway of auxin biosynthesis. Phylogenetic trees for enzyme sequences obtained were constructed. The YUCCA and TDC trees showed that these enzymes were conserved across the plant kingdom and therefore could be involved in auxin synthesis. YUCCAs branched into two clades. Most experimentally studied YUCCAs were found in the first clade. The second clade which has representatives from only seed plants contained Arabidopsis sequences linked to embryonic development. Therefore, sequences in this clade were suggested to be evolved with seed development. Examination of TDC activity and expression had previously linked this enzyme to secondary products synthesis. However, the phylogenetic finding of a conserved TDC clade across land plants suggested its essential role in plant growth. Phylogenetic analysis of AOs showed that plants inherited one AO. Recent gene duplication was suggested as AO sequences from each species were similar to each other rather than to AO from other species. Taken together and based on the experimental support of the involvement of AO in abscisic synthesis, AO was excluded as an intermediate in IAA production. Phylogenetic tree for NIT showed that the first clade contained sequences from species across the plant kingdom whereas the second branch contained sequences from only Brassicaceae. Even though NIT4 orthologues were conserved in the second clade, their major role seems to be detoxification of hydrogen cyanide rather than producing IAA.

The present investigation was aimed at enhancing the quality and productivity of barley by the fertilizer and chitosan application. The field experiments were conducted in the northern region of Jordan, under the rain fed conditions in the main growing seasons of 2014/2015 and 2015/2016. The experiment was conducted in a well-designed split-plot having three replications and two fertilizer levels (0 and 100 kg•ha-1 DAP (Diammonium phosphate 46% P 2 O 5). Chitosan, in three different concentrations (0, 5, and 10 g•L-1), was randomly applied to all fertilized plots as subplot treatments. The results revealed the highest seed dry weight (5.8 g per plant) in the plants treated with 100 kg•ha-1 of DAP, while the lowest (5.2 g per plant) was recorded in the control which exhibited an increase of about 10%. However, other parameters, namely the number of grains, number of spikes, and number of grains were also found to be influenced by the chitosan treatment. Significant variation (P<0.01) were also high between the lines in the presence and absence of chitosan application. The highest number of grain yield, number of spikes, and grains/spike were found by the foliar treatment of 10 g•L-1 chitosan to barley plants at the tillering stage. Similarly, the grain quality, particularly with respect to protein and starch, was found to be enhanced significantly over control. The highest protein (12.6%) and starch (62.3%) were obtained with 100 kg•ha-1 DAP fertilizer level mixed with 10 g•L-1 chitosan. Hence, based on results, it can be concluded that the fertilizer level 100 kg•ha-1 DAP combined with 10 g•L-1 chitosan is economically best and recommendable for improving the quality and productivity of barley in the northern region of Jordan.

A possible role for the

No abstract

No abstract

The aim of this study is to investigate the anti-hyperglycemic effect, lipid profile and the activity of certain hepatic enzymes of the ethanolic extract of the plant Arbutus andrachne on streptozotocin-induced diabetic rats. About 30 Wistar albino rats weighing between 180-200 g were randomly classified into four categories of six albino rats. The normal control group (group A) was treated orally with distilled water. The diabetic control group (group B) was induced by streptozotocin. So, this group is considered as a negative control. The non diabetic rats (group C) which was treated with the ethanolic extract of the plant A. andrachne that collected from Jerash/Jordan of a dose 200 mg kg !1. The last group (Group D) which included the diabetic rats that treated with 200 mg kg-1 of the ethanoilc extract of the plant A. andrachne. The treatment was carried out daily for 14 days. The glucose, triglycerides, cholesterol and hepatic enzymes levels were quantified in serum of experimental rats. Study was carried out in Faculty of Pharmacy/Applied Science University (December, 2018) and Botany Lab, Department of Biological sciences/University of Jordan. The results unambiguously showed that there was significant declines (p<0.05) in triglycerides and glucose levels in albino rats that treated with A. andrachne ethanolic extract compared with group B, the control group of diabetic rats. Significant reduction (p<0.05) in hepatic enzymes-AST and ALT-levels were also observed in rats treated with the plant ethanoilc extract compared with group B experimental rats. However, no significant changes in the cholesterol level were observed in the treated rats compared with the control group. Data in this piece of research revealed that the plant A. andrachne ethanolic extract has both hypoglycemic and hypolipidimic effect. This extract is suggested to reduce the liver damage induced by streptozotocin through maintaining the activity of hepatic enzymes.