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Background: Invasive plant species pose a global threat because they alter ecosystem functioning and biodiversity. The majority of plants form mutualistic mycorrhizal associations with mycorrhizal fungi, which contribute to the nutrient and water supply as well as diversity, competitive ability, and ecosystem productivity. In addition, the role of mycorrhizal interactions in plant invasiveness and the susceptibility or resistance of a habitat to invasion is increasingly recognized. However, the mechanisms by which mycorrhizae contribute to invasion remain unresolved. Scope Here, we provide an overview of the empirical evidence and discuss the prospects for mycorrhizaemediated plant invasion. Overall, mycorrhizal fungi appear to have impacts on plant invasion that depend on the similarities between the mycorrhizal associations of the alien and native plants. We introduce plant mycorrhizal niche space (PMNS) as a plant’s ability to exploit and shape the mycorrhizal fungi pool of a habitat based on its dependency on mycorrhizal fungi, traits and priority effects. Conclusions Collectively, the available evidence supports the idea that PMNS is independent of place of origin (invasive status). Understanding the drivers of the PMNS of both native and alien plant species may help to predict the potential invasiveness of plants and the invasibility of a habitat, to elucidate the role of the mycorrhizal fungal community in plant invasion and the impact of plant invasion on the structure of the mycorrhizal fungal community in new habitats (i.e., neighbour effect) and to improve restoration planning. In this regard, we highlight a number of knowledge gaps and discuss future research directions.

The study sought to evaluate the response of three groundnut genotypes (Binachinabadam-3, Dacca-1 and Zhingabadam) to various salt concentrations (D0 – Control, D1 – 2.5 dS/m, D2 – 5.0 dS/m, D3 – 7.5 dS/m, D4 – 10.0 dS/m, D5 – 12.5 dS/m) through observation of morphological and physiological characters. Based on relative performance of yield contributing characters and nutrient contents of leaves and stem, Binachinabadam-3 emerged to be a tolerant variety and based on root shoot characters, Dacca-1 appeared as tolerant while Zhingabadam always performed as sensitive variety. Salinity treatments had most adverse effects at flowering stage and followed the trend of sensitivity as flowering stage > vegetative stage> pre sowing stage > pod filling stage. All varieties were found to be tolerant up to salinity level of 7.5 dS/m.

Occurrence of chalkiness in rice is attributed to genetic and environmental factors, especially high temperature (HT). Te HT induces heat stress, which in turn compromises many grain qualities, especially transparency. Chalkiness in rice is commonly studied together with other quality traits such as amylose content, gel consistency, and protein storage. In addition to the fundamental QTLs, some other QTLs have been identifed which accelerate chalkiness occurrence under HT condition. In this review, some of the relatively stable chalkiness, amylose content, and gel consistency related QTLs have been presented well. Genetically, HT efect on chalkiness is explained by the location of certain chalkiness gene in the vicinity of high-temperature responsive genes. With regard to stable QTL distribution and availability of potential material resources, there is still feasibility to find out novel stable QTLs related to chalkiness under HT condition. A better understanding of those achievements is essential to develop new rice varieties with a reduced chalky grain percentage. Therefore, we propose the pyramiding of relatively stable and nonallelic QTLs controlling low chalkiness endosperm into adaptable rice varieties as pragmatic approach to mitigate HT effect

Pesticide helps to enhance agricultural production, however, it significantly affect both socio and environmental entities of a country. In Nigeria, pesticide is widely used, thus its traces have been detected in water, soil and air. Several studies have already indicated that most of the environmental ecology (air, water, and soil) in Nigeria has been contaminated by persistent organic pesticides like organochlorine and organophosphate. Other reasons of high pesticide residues present in Nigeria environment is due to inappropriate dosage applied of pesticides that leaves behind excess. However, its residues are found above safety levels in the air, water, and soil across the nation. Based on previous analysis, it is indicated that 125,000-130,000 metric ton pesticides are being applied annually in Nigeria. Despite banned of some pesticides such as dichlorodiphenyltrichloroethane- and -Hexachlorocyclohexane, they are still being used by farmers in their agricultural production. Many of the Class 1 (high extremely toxic) pesticides are still being used in developing countries like Nigeria. Hence, there is need to sensitize and educate the general public especially the end-users (farmers) particularly on management practices of pesticides. Considering these entire hazardous situations, in this article the history of pesticide used in Nigeria has been reviewed in detail. The article also discussed the effects of pesticide use in Nigerian waters, soil and on crops. The risk of residual pesticide on agricultural workers, pesticide residue risk preventive measures by the Federal Government of Nigeria, banned and restricted pesticides in Nigeria, Nigerian Government and its efforts to eliminate persistent organic pesticides in use are also reviewed in details.

The effects of deficit irrigation technique on growth and fruit quality of roselle (Hibiscus sabdariffa L.) was observed. The result shows that minimum weight of the yield was obtained from treatment grown with well watered (WW) condition. Plant height was affected by reduction of water application. Regulated deficit irrigation (RDI) tended to decrease all means of growth parameter except stem fresh and dry weight. RDI shows significant effect on yields, where the reduction of 50% water produce more fruits compared to control plants. The impact of RDI was not significant effect on physiological change of roselle. Thus, RDI could be a feasible technique for Roselle production as it saves large amounts of water with reduction on plant growth but increase the yield as compared to well watered (WW) of roselle.

The experiment consisted of five treatments of fermented plant juice (FPJ) and fermented fruit juice (FFJ). The treated plants with FPJ and FFJ produced early flowers and fruits compared to untreated plants due to the enhanced production of auxin and essential nutrients. Total soluble solids were also observed to increase after 10 weeks of FPJ and FFJ application. Photosynthesis rate increased in all treatments except T3; while transpiration rate increased only at T4 compared to control. The findings we clearly suggested to use both combinations as FPJ water spinach for enhancing the vegetative growth of tomato plants than FPJ bamboo shoots (T3 and T5), while FFJ pineapple for better reproductive development of tomato plants rather than FFJ banana (T5) for ensuring future sustainable eco-friendly agriculture practices.

Study was conducted to evaluate the effects of two types of fertilizers (SRI and Kamila) on growth and physiological changes of MD2 pineapple. Results showed significant changes to the growth of the MD2 pineapple due to either use of soil with NPK or in combination. Application of NPK and SRI fertilizers showed the best performance on plant height and width from beginning until 10 weeks after treatment (WAT) while for leaf length fertilizer-Kamila combination showed the best performance until 10 WAT. Equally for the chlorophyll content, the treatment Kamila also showed the best performance at 6 MAT. Analysis of leaf of the pineapple plant showed that there was a decrease in nutrient content of most the elements in 3 MAT. But for nutrient analysis of soil, the outcomes showed that at 3 MAT the nutrients content increased especially in treatment of Kamila fertilizer combination. The nutrient contents of most of the elements were also very low from what has been expected, but the result of nutrient content in soil treated with Kamila - a controlled-release fertilizer showed a good result. Addition of controlled release fertilizer (Kamila) with SRI formulation showed positive improvement in the plant growth of pineapple variety MD2 compared to the plants without SRI formulation.

The application of indigenous microorganism (IMO) and system of rice intensification (SRI) Anak formulation on growth and nutrient uptake of rice variety MR219 at nursery level was carried out. Results showed the highest plant height, leaf area, fresh and dry weight of rice variety MR219 when treated with IMO and SRI Anak formulation. Accumulation of N, P and K content in leaf and root tissue is much affected by spraying with SRI formulation. IMO had less influence in increasing the nutrient content in leaf and root tissue at nursery level. IMO and SRI formulation is potentially to be used as bio-fertilizer and bio-regulator to reduce environmental problems.

The physico-chemical properties of abscisic acid (ABA) and IAA treated roselle calyces stored in different storage temperature was determined in this study. Mature roselle was dipped in distilled water (control),10-4 mol/l of ABA and 10-4mol/l of IAA for 5 minutes. All treated calyces were kept at ambient temperature (23°C) for 4 days, or stored at cold storage (10°C) for 8 days. Low temperature (10°C) can prolong the shelf life of roselle about 4 days longer than ambient storage (23°C). However, plant growth regulator (ABA or IAA) only showed minimal effect on quality and shelf life of roselle. Therefore,the application of higher concentration of ABA or IAA as well as dipping for more than 5 minutes can influence the postharvest quality and shelf life of roselle calyces, respectively.

The study was conducted to evaluate the responses of rice and rice weed seedlings (barnyardgrass and weedy rice) at the three-leaf stage to Tinospora tuberculata leaf methanol extract (3.12, 6.25 and 12.5 g L−1) under hydroponic culture. It shows that the leaf methanol extract had various degrees effects depending on target plant species and each tested index (biomass, root length, shoot length, transpiration volume, chlorophyll a, chlorophyll b and carotenoid contents). The effective concentration of the leaf extract capable of reducing 50% of rice growth was higher than those of target weed species. Moreover, the root length was more tolerant to leaf methanol extract in comparison to the other plant parameters measured. A greater reduction was observed in chlorophyll a content compared to chlorophyll b and carotenoid. The results revealed that the reduction of transpiration volume closely coincided with the magnitude of growth inhibition of tested plants. Ultra-fast liquid chromatography analysis revealed 11 of 32 peaks in chemical profile, including benzoic acid, caffeic acid, chlorogenic acid, isoorientin, isovitexin, orientin, p-anisic acid, syringic acid, trans-cinnamic acid, trans-ferulic acid, and vitexin have the same retention time with those peaks of the extract. The amount of compounds was present in the range of between 4 817 and 115.5 mg kg−1 dry weight (DW). The concentration-response bioassay of all 11 individual compounds and their equimolar mixture against the seeds of barnyardgrass revealed their contribution in the allelopahic activity of T. tuberculata leaf extract. The examined compounds and their combination exhibited various degrees of growth inhibitory effects on the early growth of barnyardgrass. Therefore, the specific number, concentration, combination and inhibitory activity of bioactive compounds leads to allelopathy activity of T. tuberculata leaves which could be employable directly as a natural herbicide and its growth inhibitor comp

The experiment was conducted to study Cynodon dactylon morphological improvement and breeding by induced mutation using gamma ray irradiation at Universiti Putra Malaysia (UPM) and Malaysian Institute of Nuclear Technology Research (MINT) center. C. dactylon is a widely used turf in Malaysia especially for golf course and football field. However, its coarse leaf texture and long internodes are undesirable for good quality golf field. In this purpose mutagenesis by gamma ray irradiation was employed using 0, 20, 40, 60, 80, 100, 120 and 140 Gy to treat 30 single node stolons per treatment. Dosages of 90 Gy were determined as LD50 for the radio sensitivity test. Survival rate of C. dactylon stolon was greatly reduced when irradiated with higher dosages. This experiment was repeated using LD50 on 1500 single node stolons. Twenty two (22) morphological mutants were identified and evaluated. Most mutants were semi-dwarf type with reduced internode length and leaf blade length. The altered morphological traits were stable after third cutting back (M1V3) shown by their morphological performance. Mutation breeding is effective in improving C. dactylon when easily recognized cultivars are needed.

BACKGROUND: Blast caused by the fungus Magnaporthe oryzae is a significant disease threat to rice across the world and is especially prevalent in Malaysia. An elite, early-maturing, high-yielding Malaysian rice variety, MR263, is susceptible to blast and was used as the recurrent parent in this study. To improve MR263 disease resistance, the Pongsu Seribu 1 rice variety was used as donor of the blast resistance Pi-7(t), Pi-d(t)1 and Pir2-3(t) genes and qLN2 quantitative trait locus (QTL). The objective was to introgress these blast resistance genes into the background of MR263 using marker-assisted backcrossing with both foreground and background selection. RESULTS: Improved MR263-BR-3-2, MR263-BR-4-3, MR263-BR-13-1 and MR263-BR-26-4 lines carrying the Pi-7(t), Pi-d(t)1 and Pir2-3(t) genes and qLN2 QTL were developed using the simple sequence repeat (SSR) markers RM5961 and RM263 (linked to the blast resistance genes and QTL) for foreground selection and a collection of 65 polymorphic SSR markers for background selection in backcrossed and selfed generations. A background analysis revealed that the highest rate of recurrent parent genome recovery was 96.1% in MR263-BR-4-3 and 94.3% in MR263-BR-3-2. CONCLUSION: The addition of blast resistance genes can be used to improve several Malaysian rice varieties to combat this major disease.

This study was undertaken to determine the effects of varied salinity regimes on the morphological traits (plant height, number of leaves, number of flowers, fresh and dry weight) and major mineral composition of 13 selected purslane accessions. Most of the morphological traits measured were reduced at varied salinity levels (0.0, 8, 16, 24 and 32 dS m-1), but plant height was found to increase in Ac1 at 16 dS m-1 salinity, and Ac13 was the most affected accession. The highest reductions in the number of leaves and number of flowers were recorded in Ac13 at 32 dS m-1 salinity compared to the control. The highest fresh and dry weight reductions were noted in Ac8 and Ac6, respectively, at 32 dS m-1 salinity, whereas the highest increase in both fresh and dry weight was recorded in Ac9 at 24 dS m-1 salinity compared to the control. In contrast, at lower salinity levels, all of the measured mineral levels were found to increase and later decrease with increasing salinity, but the performance of different accessions was different depending on the salinity level. A dendrogram was also constructed by UPGMA based on the morphological traits and mineral compositions, in which the 13 accessions were grouped into 5 clusters, indicating greater diversity among them. A three-dimensional principal component analysis also confirmed the output of grouping from cluster analysis.

The world's population is increasing very rapidly, reducing the cultivable land of rice, decreasing table water, emerging new diseases and pests, and the climate changes are major issues that must be addressed to researchers to develop sustainable crop varieties with resistance to biotic and abiotic stresses. However, recent scientific discoveries and advances particularly in genetics, genomics and crop physiology have opened up new opportunities to reduce the impact of these stresses which would have been difficult if not impossible as recently as the turn of the century. Marker assisted backcrossing (MABC) is one of the most promising approaches is the use of molecular markers to identify and select genes controlling resistance to those factors. Regarding this, MABC can contribute to develop resistant or high-yielding or quality rice varieties by incorporating a gene of interest into an elite variety which is already well adapted by the farmers. MABC is newly developed efficient tool by which using large population sizes (400 or more plants) for the backcross F1 generations, it is possible to recover the recurrent parent genotype using only two or three backcrosses. So far, many high yielding, biotic and abiotic stresses tolerance, quality and fragrance rice varieties have been developed in rice growing countries through MABC within the shortest timeframe. Nowadays, MABC is being used widely in plant breeding programmes to develop new variety/lines especially in rice. This paper reviews recent literature on some examples of variety/ line development using MABC strategy.

A glasshouse experiment was conducted in Universiti Putra Malaysia (UPM) to evaluate the regeneration and yield potential in purslane using both seeds and stem cuttings of 20 collected accessions from different locations in Western Peninsular Malaysia. Analysis results revealed significant variations (P< 0.05) for morphological traits viz., plant height, number of main branches, number of nodes, internodal distance, stem diameter, number of leaves, leaf area, number of flowers, root length, fresh and dry weight but no significant difference were observed for physiological traits viz., total chlorophyll, net photosynthesis, stomatal conductance, transpiration, water vapor deficit and for either major micro or macro minerals. Hope our research findings will eliminate the doubt of using cutting methods for purslane propagation and cultivation among producers and consumers and will promote their determination to follow purslane production in this summer at any season and anywhere. To the best of our knowledge, this is the first attempt to evaluate and to detect any significant variations arising in morphological, physiological, and especially mineral nutrition in purslane propagated through cuttings vs. through seeds.

Herbicidal potential of aerial parts of Tinospora tuberculata on germination and seedling growth of seven test plant species, namely rice (Oryza sativa L.); two rice weeds, barnyardgrass (Echinochloa crus-galli L.) and weedy rice (O. sativa f. spontanea); and four vegetable crops, lettuce (Lactuca sativa L.), tomato (Solanum lycopersicum L.), carrot (Daucus carota L.), and cucumber (Cucumis sativus L.) were evaluated. Six concentrations of methanol extract (3.12, 6.25, 12.5, 25, 50, and 100 g L−1) were compared with the control (distilled water). The rate of seed germination and the radicle and hypocotyl length of 7-day-old test plant seedlings were reduced as the concentration of extracts increased compared to the control. Generally, the degree of toxicity of extracts derived from the leaves was more than the extracts derived from the stem. Cluster analysis and the concentrations required for 50% inhibition (defined as EC50) of all parameters showed that radicle growth was more suppressed than germination and hypocotyl growth. Lettuce and carrot were observed as the most sensitive plants while rice showed the highest tolerance to both extracts. Moreover, the dicot target plants were affected more severely than the monocots when treated with leaf extract. The chemical composition of the T. tuberculata methanolic extracts was analyzed by a GC–MS system. A total of 92 and 22 constituents (not previously identified) were found in the leaves and stem, respectively. The results showed that 17 of the 92 components in the leaves, as compared to 4 of 22 compounds in the stem, are known as toxic compounds. These results suggest that T. tuberculata contains a significant source of plant growth inhibitors with potential for the development of future natural herbicide.

A field experiment was conducted to evaluate the residual effects of organic manures and different level of recommended fertilizer dose (RFD) on the yield and nutrient uptake of BBRI dhan29 at the Soil Science Field Laboratory of Bangladesh Agricultural University, Mymensingh, Bangladesh. The experiment containing seven treatments were laid out in a randomized complete block design with three replications. The treatments were T0 (Control), T1 (100% RFD), T2 (75% RFD + residual effect of CD 5 t ha-1), T3 (75% RFD + residual effect of PM 3 t ha-1), T4 (75% RFD + residual effect of residual effect of Com. 5 t ha-1), T5 (75% RFD + residual effect of CD 2.5 t ha-1, PM 1.5 t ha-1, and Com 2.5 t ha-1) and T6 (50% RFD + residual effect of CD 2.5 t ha-1, PM 1.5 t ha-1, and Com. 2.5 t ha-1). The manures viz. cowdung (CD), poultry manure (PD) and compost (Com.) was applied to the previous crop (T. Aman rice). The recommended doses of fertilizers were used to supply N, P, K and S @ 140, 15, 60 and 15 kg ha-1, respectively to the present crop. Residual effects of organic manure with inorganic fertilizers significantly increased the yield attributes as well as grain and straw yields of rice. Treatment T6 (50% RFD + residual effect of CD 2.5 t ha-1, PM 1.5 t ha-1, and Com. 2.5 t ha-1) produced the highest grain yield (6.87 t ha-1) and straw yield (7.24 t ha-1). The lowest grain yield (3.22 t ha-1) and straw yield (4.55 t ha-1) were found in T0 (Control) treatment. Further, it was observed that T2 (75% RFD + CD 5 t ha-1) performed better compared to T3 (75% RFD + PM 3 t ha-1) and T4 (75% RFD + Com 5 t ha-1) in exerting residual effects. The NPKS contents and uptake were markedly influenced by residual effects of manures and fertilizers. Therefore, treatment T6 receiving 50% RFD along with the residual effect of 2.5 t ha-1 cowdung, 1.5 t ha-1 poultry manure and 2.5 t ha-1 compost was found to be the best combination of organic and inorganic fertilizers for obtaining the maximum yiel

Global warming is already having significant and costly effects on our climate, our health, our environment and overall agricultural system. Global warming is also accelerating the rate of sea level rise, increasing flooding risks to low-lying communities, high-risk coastal properties, causing severe salinity and making agricultural land unsuitable for crop production. Considering such situation environmental friendly technologies with stress tolerant crop species is the only solution for sustainable agricultural development. Purslane (Portulaca oleracea L.) is a pioneer vegetable crops having moderate to high salt tolerant capability containing vitamins and minerals and rich in antioxidant properties than any other vegetable crops ever reported. The present study was therefore designed to select high salt tolerant purslane accessions and their morpho-physiological variation due to salinity stress as well as impact on antioxidant properties. A survey was conducted to collect available purslane accessions from seven states (Selangor, Melaka, Negeri Sembilan, Kedah, Perak, Penang and Perlis) of Western Peninsular Malaysia. A total of 45 purslane samples were collected and divided into seven different groups based on distinct morphological variation. Morpho-physiological and mineral variations were also evaluated among collected purslane accessions. Highly significant variations were observed among accessions as well as measured parameters. Variations were also recorded among the same groups may be due to collection from different location. Twenty eight ISSR and ten EST-SSR markers based genetic diversity analysis was carried out among collected purslane germplasms. Analysis of molecular variance (AMOVA) showed 89% and 71.87% variation within the populations while variation among the populations accounted for 11% and 28.13% using ISSR and ESTSSR markers respectively. A dendrogram was constructed by Unweighted Pair Group Method with Arithmetic Average (UPGMA) based on N