Terminal flower 1(TFL1) homolog genes in dicot plants

Terminal flowering1 (TFL1) is an important gene responsible for time of flowering in Arabidopsis thaliana. It belongs to phosphtidyl ethanolamine binding protein domain PEBP gene family. Throughout the past decade, genetic studies have found out several TFL1 like genes in dicots and monocots plants. In this paper, current advances in TFL1 homolog isolated from different dicot species, has been addressed. Arabidopsis thaliana, Antirrhinum majus, Brassica naapus, Citrus sinensis L, Pisum sativum, Vitis vinifera L, Beta palonga, Lotus japonicus, Lycopersicon esculentum, Impatiens balsamina, populus trichocarpa, Malus xdomestica, Pyrus pyrifolia, Pyrus communis, Cydonia oblonga, Chaenomeles sinensis, Cucumis sativus, Gossypium hirsutum,Capsicum annuum L.and Eriobotrya japonica are dicot plants which their TFL1 homologs will be discused here. Moreover, similarity and differences between them and other known genes, have been compared

Status of root knot nematode disease on kenaf cultivated on BRIS soil in Kuala Terengganu, Malaysia

A field survey was carried out to investigate kenaf plants cultivated in Telaga Papan, Terengganu, Malaysia with respecting to their performance, root galling and growth characteristics. In this investigation, the aims were to assess the status of nematode infection on kenaf planted on this sandy BRIS area and estimate the incidence and severity of infection. Inspection of kenaf plants showed decolorating, drying and wilting of their leaves along with developing of galls on their root. Leaf colour and plant performance were found to be significantly different between infected and control plant. Infection with nematode was detected to reduce height, stalk diameter and number of node in kenaf plants. Root galling severity and percentage of active galls in kenaf roots were calculated as well. They showed to be closely correlated to each other. However, the relation between root galling severity and height was higher than with diameter and number of node

Effect of root knot nematode on growth and agronomic traits of Hibiscus cannabinus L. varieties

The purpose of the current study was to determine the effect of root-knot nematode infection on the growth of kenaf. Seeds of sixteen (16) varieties of kenaf, comprising of eight from Australia, three local and five accessions from Bangladesh were planted under controlled condition and inoculated with four level of 0, 1000, 5000 and 10000 RKN eggs per plant. The growth parameters of height, stalk diameter and number of node of plants were measured at interval of 30, 60, 90 and 120 days after planting. The results of this investigation showed that all kenaf plant cultivars studied here, differed in growth parameters (P= 0.05) both in the absence and presence of nematode infection. M. incognita race 1 was found that can infect all of these cultivars. The damage due to nematode; however; differed based on cultivar, level of inoculation and month of growth. Reduction of plant height and stalk diameter was observed in all inoculated varieties. Number of internode, however; was increased instead. In different growing time, the values for these parameters were shown to be different as a function of growing age and nematode infection. When infected with RKN, a superiority of varieties KK60 (M), G4 (AUST) and entry 3740 concerning to others were observed for height, stalk diameter and internode respectively. The growth parameters of resistant varieties treated with RKN was significantly better over the time as compared to the susceptible one

Isolation and identification of diazinon degrading bacteria from fresh water: a case study on the sediments of Lake Parishan in Iran

Diazinon is an organophosphate insecticide which is widely used in various industries. It is known as an important causative of water pollution which eventually redound death of aquatic animals. Today microorganisms are considered as a best choice to reduce environmental pollution. This study was done to identify diazinon degrading bacteria from sediments of Lake Parishan (IRAN) and to evaluate their degrading rate as well. Sampling was done from the surface sediments of Lake Parishan and its surrounding farms during summer, autumn and winter, then incubated in liquid salt medium containing diazinon for 20 days at 35°C. After growing, bacteria were transferred to solid saline medium. They were identified using biochemical tests; thereafter in order to evaluate their ability in degrading of diazinon, diagnostic tests were performed. Result showed that bacteria Pseudomonas, staphylococcus, Bacillus, Corynebacterium, Acinetobacter, Alcaligenes, Serattia, Salmonella, Citrobacter and Providencia are able to degrade diazinon. Among them Pseudomonas was the strongest in summer and winter, while Citrobacter was the most preferable bacterium in fall. It was also detected that combined population of Gram positive and Gram negative bacteria together are able to degrade diazinon faster. Therefore, the present study confirmed the application of bacteria for reducing diazinon pollution in waters considering their ease and economical application

Terminal flower 1(TFL1) homolog genes in monocots.

Terminal flower1 (TFL1) is a key gene in charge of flowering time in Arabidopsis thaliana. It belongs to a family of phosphatidyl ethanolamine binding protein domain (PEBP). The main issues addressed in this paper are current advances in TFL1 homologs isolated from the monocot plants include rice (Oryza sativa) and ryegrass (Lolium perenne). Taking advantage of previous studies of cloning, in this review we have evaluated function of these genes in regulating flowering time as well as the effect of altered expression of these genes. It will then discuss or address places or parts of these plants where these genes express. Additionally, structural and functional relationships between them are compared

Function and expression pattern of Terminal Flower 1 (TFL1) homolog genes in dicot plants.

Terminal floweringl (TPLI) is a key gene in charge of flowering time inArabz'dopsz's thaliana. During the past decade, genetic studies have found out several TFL] like genes in dicot plants. The main issues addressed in this paper are current advances in TFL] homologs isolated from different dicot species and their function in flowering. Taking advantage of previous studies of cloning, in this paper we have evaluated function of these genes in regulating flowering time. It will then go on to place or parts of plants in where these genes express. Moreover, similarity and differences between them and other known genes, have been compared

Responses of some kenaf (Hibiscus cannabinus L.) varieties to root knot nematode infection

Kenaf is a fast growing crop cultivated for its natural fibre. It is one of the potential multipurpose crop species in Malaysia which thrives relatively well in less fertile BRIS (Beach Ridges Interspersed with Swales) soils. Despite growing relatively well in this area, there is a threat of infection with Root Knot Nematode (RKN) which can potentially reduce the growth and yield production of this crop. However, the knowledge on nematode infection that may affect gas exchange characteristics and enzymatic defence mechanisms of kenaf still remains limited. Moreover, as traditional method of nematode management is time consuming, laborious and associated with health and environmental concerns, thus the host resistance and screening based on molecular markers would be a preferable choice to apply. The study evaluated disease incidence of RKN and its severity on kenaf plants cultivated in sandy BRIS soils in Telaga Papan, Terengganu, Malaysia following which a subsequent screening was made on the Hibiscus cannabinus varieties for their growth, productivity, resistance, physiological and enzymatic responses to RKN infections. In addition, the study determined the genetic mode of the RKN resistance inheritance in the F2 populations those were derived from crosses of resistant and susceptible plants which was further verified by the ISSR markers which were associated with this resistance. Investigation on kenaf cultivated in BRIS soils exhibited a severe nematode infection (Meloidogyne incognita) of Race 1, which was significantly correlated with the reduction in height (R2= - 0.73), diameter (R2= - 0.60) and number of nodes (R2= - 0.70). Screening of sixteen kenaf varieties from different origin was conducted using three levels of artificial inoculation viz; 1000, 5000 and 10000 eggs per pot under controlled condition with untreated plant as control showed that the average height and stalk diameter of the infected plants were reduced by 10.62% and 9.95% respectively during harvesting time of 120 days. The effects were significantly different between varieties and time of measurement. Variety KK60 (M) outperformed the others with height (214.44 cm), stem diameter (14.19 mm) and number of nodes (52) while variety 3740 performed the poorest in terms of height (115.89 cm) and stem diameter (9.94 mm) and variety 113 produced the lowest number of nodes (32) upon RKN infection. Inoculation with M. incognita decreased kenaf height and diameter at a range of 0.37% to 24.79% and 1.4% to 16.5% respectively. Variety 113, KK60 (Aust) and Everglades 41 recorded the highest reduction in height (24.79%), diameter (16.5%) and internodes number (18.5%) respectively. On the contrary, variety 4638 recorded the least decrement in height (0.37%) and diameter (1.4%) respectively. Resistant variety (Gregg) recorded reduction in height and stalk diameter of 9.84% and 3.04% respectively while the susceptible variety (Everglades 41) produced bigger reduction of 14.55% and 8.46% for similar parameters. The highest reduction of height and diameter occurred in the third month and the first month respectively. Different varieties reacted differently with levels of nematode inoculation for all characteristics studied here. In addition, infected plants also recorded bigger losses in yield than the control. Measurement of gas exchange characteristics in infected plant showed that nematode has decreased the values of Assimilation rate (A), transpiration rate (E), intercellular CO2 concentration (ci) and Vapour Pressure Deficit based on Leaf temperature (VPDL) by 22.50%, 32.30%, 21.62% and 34.80% respectively whilst increased both water use efficiency and intrinsic water use efficiency. The different varieties used in the experiment also showed different responses of gas exchange to nematode infection. Susceptible variety showed higher assimilation rate and water use efficiency than the resistant variety. In turn, the value of stomatal closure, transpiration rate, VPDL and intrinsic water use efficiency (A: gs) for susceptible was lower than the resistant variety. Examining of individual plant based on three (3) parameters i.e. gall index ratings, egg mass index and egg per gramme root of plant showed that variety Everglades 41 is more susceptible to M. incognita Race 1 having value of 4.33, 4.89 and 16985 as compared with variety Gregg that exhibited resistance response with value of 1.67,2.33 and 2691 for the above mentioned parameters respectively. Study on biochemical basis of resistance to M. incognita in kenaf showed a significant increase of peroxidase activity in the roots of both susceptible and resistant plants when compared to the non-inoculated control plants. The resistant host exhibited five times higher peroxidase activity than the susceptible ones upon infection with nematode. Examining of resistance to RKN using gall index in F1 and F2 populations showed segregation pattern that fits the Mendelian ratio of 1: 3 (resistant: susceptible). Further investigation using sixty (60) Inter Simple Sequence Repeat (ISSR) primers revealed polymorphism between resistant and susceptible parents. Two markers ISSR 807 and ISSR 837 were found to be associated with RKN resistance trait. The phenotype variation explained by these markers accounted by 33.88% and 33.71% respectively. In conclusion, variety KK60 is the most recommended variety to be planted on sites which are proned to RKN infestation such as BRIS soils eventhough it was not found to be resistant against RKN. This is based on its overall growth performance and yield productivity upon infection with RKN. The study also revealed that screening for resistance against RKN using ISSR markers is an important reliable tool to be incorporated in kenaf improvement programme