Maize crop is the third most important cereal crop, mostly grown for food, feed and fodder purpose. In spite of the fact the crop is susceptible to salt stress but exhibits a considerable genotypic variability for salt tolerance. The present study was carried out to determine to which extent the maize genotypes with contrasting morphological traits respond to salt stress. Seven days old seedlings of thirty maize genotypes were exposed to NaCl stress of EC less than 4 (control), equal to 8 and 12 dS m -1 for further 28 days in a temperature controlled greenhouse. The salt stress imposition was completed in two increments every other day from the date of planting. At the age of 35 days, the seedlings were evaluated for contrasting morphological traits. The genotypes exhibited considerable variations for each of the 10 measured morphological and ionic traits. PCA was employed to identify the most suitable morphological trait to be used as selection criterion for salt tolerance. Based on the PCA results, dry shoot weight (DSW) was used to classify thirty maize genotypes into salt-tolerant-T, moderately tolerant-MT and salt sensitive-S groups. Two (2) out of thirty genotypes i.e. SB-9617 and FH-949 had the highest average of percent dry shoot weight (PDSW) values > 70% were classified as salt tolerant (T). The fifteen (15) genotypes showed average of PDSW values in the range of 55-69.9 % were classified as moderately tolerant (MT) by indicating the sequence order of salt tolerance as YH-1898 > MMRI-yellow > S-2002 > FH-988 > FH-1292 > HC-12 > MS-2018 > NCEV-1270-7 > Pahari > Pearl White > FH-1114 > NCEV-1270-3 > Iqbal > NCEV-1297 > DK-6724. However, thirteen (13) out of total thirty (30) genotypes attained the average PDSW values <55% were classified as salt sensitive (S) following the sequence order as NCEV-1530-9 > Composite > FRI-22 > Azam > MS-2015 > P-1543 > Neelum > Afgoi > Malka-2016 > MS-1501 > HNG > NCEV-1270-5 > NCEV-7004. It was also noticed that the declared salt tolerance was positively correlated with dry shoot weight (DSW), shoot length (SL), stem diameter (SD), fresh shoot weight (FSW), fresh root weight (FRW), dry roots weight (DRW), root length (RL), leaf area per plant (LA), number of leaves per plant (NL) and K + /Na + ratio. The highest positive Pearson correlation coefficients were determined in LA vs SD (r=0.900), DSW vs SD (r=0.899), SL vs DSW (r=0.891), SL vs FSW (r=0.890) and DSW vs FSW (r=0.887). Additionally, the salt tolerant (T) group of genotypes maintained higher K + /Na + ratios compared to moderately tolerant (MT) and salt sensitive (S) groups. The results clearly showed that dry shoot weight (DSW) could be viable option to classify maize genotypes into different salt tolerance groups and to identify the most suited and best adapted salt tolerant genotype for cultivation in saline soils. Furthermore, this scientific information could help the plant scientists to improve and develop the new salt tolerant cultivar.
This research was carried out at Khyber Pakhtunkhwa Agricultural University Peshawar to evaluate the performance of maize inbred lines derived from maize variety Sarhad White regarding grain yield and morphological traits and identifying superior inbred lines based on test cross performance. Test crosses were evaluated in replicated trial along with two tester, one check and 16 parental inbred lines for comparison in a 7×7 partially balanced lattice square design with two replications. Results revealed highly significant differences among the genotypes for most of the traits. Jalal TC-230-a and TC-63-1 took the maximum days to tasseling and Jalal TC-101-2 showed maximum days to anthesis. Maximum day to silking and anthesis silking interval were recorded in Jalal TC-94. Maximum plant height was observed in Jalal TC-33 (164.5 cm) and Kiramat TC-9-6-1 (141.50 cm). Maximum 100 kernal weight was recorded in Jalal TC-101-2 (40.55 g). Kiramat TC-89-b produced the highest grain yield (6808 kg ha -1 ). From these results, it can be concluded that Kiramat TC-89-b, having highest yield, could be promoted for further selfing. Jalal TC-9-6, TC-9-6-1, TC-12-1, TC-63-1, TC-76-2b, TC-89b, TC-163, TC-205, TC-230a, TC-211 and Kiramat TC-9-6, TC-9-6-1, TC-12-1, TC-33, TC-76-2b, TC-89b, TC-94, TC-101-2, 150-c, TC-163, TC-230-a, 205, 211, 226-2 in addition to having satisfactory grain yield could be used for selfing. Among parental lines (selfed lines) 9-6-1, 9-6, 10-2, 226-2, 33, 63-1, 76-2, 163, 89-b, 205 and 211 were promising for grain yield and morphological traits.
Yield reduction in okra production is mostly associated with cultivation of marginal lands or continuous land cultivation. Hence, the need for sustainable approach to resuscitating soil fertility through Tithonia diversifolia manure application may alter microbial population. Two soil depths [Topsoil (0-15 cm) and Subsoil (15-30 cm)], three levels of Tithonia manure applications (control, half recommended and recommended at 120 kg N/ha) and three okras varieties (Clemson spineless, LD88 and NHAe 47-4) were evaluated in completely randomized design replicated thrice. Soil bacterial and fungal colonies were higher in the topsoil compared to the subsoil and increased with increase in level of tithonia manure application under topsoil, while the inverse was observed under subsoil condition for bacteria colony-forming units and mycorrhizal spore count. Under topsoil, LD88 variety treated with recommended rate of tithonia manure had the highest biomass dry matter (79.4 g). Significantly higher leaf area (395.92 mm 2 ) and biomass dry matter (66.89 g) were produced by NHAe 47-4 and Clemson spineless treated with recommended rate of tithonia manure compared to their respective controls (181.37 mm 2 and 29.63 g) under subsoil. Varieties LD88 and Clemson spineless combined with recommended rates of tithonia manure were suggested for topsoil and subsoil conditions, respectively.
The article presents the results of studies physiology of nutrition of juveniles individuals of pumpkinseed Lepomis gibbosus (Linnaeus, 1758) from the Zaporizhzhia (Dnipro) reservoir. histological structure, morphometric parameters of digestive system and nutrition biology were investigated. The material for work were collected during scientific research in June-July 2016–2017. The ichthyological sampling was carried out in the Samara Bay of the Zaporizhzhia (Dnipro) reservoir. Researches of structure of digestive system were conducted using histological methods, researches of nutrition were conducted using ichthyological and hydrobiological methods The height of the intestinal epithelium of the pumpkinseed`s juveniles varies from 15.5 microns to 51.9 microns and on average is 32.59 ± 9.03 microns, the area of secretory goblet cells of the intestine reaches 198.61 ± 36.55 μm 2 . It was revealed that the pumkinseed’s juveniles only feed on phytoplankton. Research results can be useful for further study on the fish nutrition, especially sexual matured. Also, nutrition studies can help to find biomeliorative methods to combat the pumpkinseed, because the species is in competition with industrially valuable species of fish for fodder.
Imidacloprid is a widely used pesticide that belongs to the class of neonicotinoids. There is a piece of rising evidence that neonicotinoids exert cytotoxic effects in non-target organisms including vertebrate species such as mammals. Nevertheless, dose-limiting toxicity and molecular mechanisms of neonicotinoids' deleterious effects are still poorly understood. In accord to imidacloprid fate in the environment, the most of used pesticide is absorbed in the soil. Therefore, earthworms, which are prevailing soil organisms, could be considered as a target of neonicotinoids toxicity. The earthworm’s simple nervous system is a prospective model for neurotoxicological studies. We exposed earthworms to imidacloprid in a paper contact test with a doses range of 0.1‑0.4 µg/cm 2 for 14 days. In the present work, we studied the imidacloprid effect on oxidative stress generation and neuronal marker neuron-specific enolase (NSE) expression. The exposure to imidacloprid induced a dose-dependent decrease in NSE. Both reactive oxygen species production and lipid peroxidation level were upregulated as well. Observed NSE decline suggests imidacloprid-caused disturbance in earthworm neuron cells. Obtained data have shown that relatively low doses of imidacloprid are potent to induce cytotoxicity in neurons. Furthermore, neurotoxicity could be recognized as one of an individual scenario of the general imidacloprid toxicity. Thus, presented results suggest the cytotoxicity of imidacloprid low doses in non-target organisms and hypothesize that NSE downregulation could be estimated as a biomarker of neonicotinoid cytotoxicity in a nervous system of non-insect species.
In the global outlook, letting of untreated sewage in existing river bodies deteriorates the water quality. The seepage likely depreciates the quality of ground water too. The quality of groundwater with special reference to India has tremendously gone down in the past twenty years leading to sour taste. On the other hand, agriculture sector is deprived of water in many places of India. A solution can be arrived concurrently by treating sewage and consuming the effluent in agricultural sector. First order kinetics was applied in constructed wetland system at different flow rates and optimised. At optimised HLR, effluent met the standards of discharge that can be utilized for agricultural/ irrigational purpose. The emanating major pollutants can be effectively treated using constructed wetland system under tropical climate. A few clippings at the onsite treatment illustrated the diversity of species thus adjoining sustainable biodiversity and treatment. Thus in tropical countries like India, constructed wetland system might pave solution not only for the treatment of sewage but in deploying the effluent in agricultural sector. A clean ecosystem can be achieved with sustainability.
The production functions of water-dependent sectors of the economy can include the water level in the lake as a natural resource. This characteristic must be able to reliably predict for the effective functioning of sectors of the economy. In the article the main attention is paid to the methods of forecasting based on the extrapolation of natural variations of the large lakes water level. As an example, is considered. In this paper, it is assumed that the level varies accordingly to a stochastic multi-cycle process with principal energy-containing zones in frequency bands associated with seasonal and multi-annual variations. Hence, the multi-year monthly and yearly averaged time series are represented by the ARIMA (auto-regression integrated moving average) processes. Forecasts are generated by using of the seasonal ARIMA-models, which take into account not only the seasonal but also the evolution non-stationarity. To compare the forecasts and the actual values, the relative errors are computed. It is shown that implementation of the models mainly allows receiving good and excellent forecasts. Subject Classification Numbers: UDC 556.555.2.06(4)
Field experiment was conducted in Giza, Egypt, during two growing seasons of 2017-2018 and 2018-2019 on garlic crop, with the objective of investigating the effect of different irrigation levels (60, 80 and 100 % of water requirements and their combination with the foliar spraying applications of agrispon (with 0.5 and 1.0 ml/ liter) on growth and yield. The results indicated that increased irrigation level up to 100% led to increased vegetative characters of garlic and that the lowest growth and productivity was obtained by 60% irrigation level. When considering spray application of agrispon; with 1.0 ml/L increased growth and productivity followed by 0.5 ml/L; while control treatment gave the lowest productivity during the both seasons. Interaction effect between irrigation level and agrispon treatments indicated that 100% irrigation level combined with 1.0 ml/L spray application of agrispon gave the highest garlic productivity followed by 100% irrigation level combined with 0.5 ml/L spray application. The chemical analysis showed that the highest NPK was obtained by 100% irrigation level combined with 1.0 ml/L agrispon application during the both seasons. Regarding water footprint, the highest irrigation water footprint was obtained by 80% irrigation level followed by 60% irrigation level, while the lowest footprint was obtained by 100% irrigation level due to high garlic productivity under 100% irrigation level. The estimate water footprint for garlic was 525 m3/ton. The blue water footprint for garlic was 422 m3/ton about 80% form total water footprint, while gray water percentage about 20% with value of 103 m3/ton.
The growth of man-caused load on natural objects, including surface waters, gave impetus to the studying for issue of water pollution in Ukraine by various pollutants. Especially relevant for us are the studies of fishery reservoirs as a direct environment for growing quality aquaculture products. Among the toxic compounds contained in reservoirs, one of the first places is occupied by heavy metals. On the one hand, heavy metals, as pollutants in natural waters, pose a great danger because even in relatively small concentrations they can adversely affect aquatic organisms. On the other hand, in microquantities most heavy metals (except mercury, cadmium and lead) are a natural and even essential component of living cells of aquatic organisms, including fish [17,19].Zn, Mn, Fe, Cu, Pb, Co, Ni, Cd in the organs and tissues of the bighead carp hybrid form, which was cultivated in ponds from highly urbanized territory, are distributed heterogeneously and their level of content depends not only on the physical and chemical characteristics of the aquatic environment or this heavy metals biochemical activities force in fish organisms, but also on functional features of concrete organs and tissues of the latter. Results of our investigations showed that above mentioned heavy metals were characterised by high levels of content in the organs and tissues of hybrid silver x bighead carp . Highest content in organism of hybrid are lead, cobalt, and cadmium. Highest concentration of heavy metals in our investigations was recorded in gills, because it is the first defence line of fish organism from environmental pollutants.
Sewage treatment through constructed wetland is an ecofriendly and sustainable approach proven effective worldwide. Constructed wetland with appropriate species is capable of eliminating all pollutants in sewage, except pathogen removal. An additional polishing treatment is required to eliminate pathogen. Optimization of HLR in CWS was executed by applying first order kinetics. Nanocomposite clay filter with economically viable materials was synthesized and disinfection ability was evaluated. A novel approach integrating constructed wetland system tailed by nanocomposite clay filter was designed. Control was setup with constructed wetland system devoid of plants integrated with clay filter devoid of nanoparticles. The constructed wetland system devoid of plants was used as plants play a vital role in the removal of pollutants. The quality of the influent for (n=20) BOD, COD, TKN, TP, TSS, TDS, SO4, Cl, lead and iron were 248, 345, 26, 4.8, 350, 450, 50, 48, 0.2, 5 mg/L respectively. The quality of effluent in the control was 145, 225, 18, 3.8, 185, 345, 31, 30, 0.6, 2 mg/L for BOD,COD, TKN, TP, TSS, TDS, SO4, Cl, lead and iron respectively. While in the test, 10, 30, 2, 1, 30, 128, 13, 12, BDL, BDL mg/L for BOD, COD, TKN, TP,TSS, TDS, SO4, Cl, lead and iron respectively. The inlet concentration of T.C, F.C and E.coli were 42.1x10(6)- 6.3x10(8) , 4.9x10(5)-14.4x10(6) and 7.8x10(3)-3.8x10(5) respectively. The pathogen reduction in log removal for test and control units were 5.4 and 1.1 for T.C, 4.4 and 1.2 for F.C and 3 and 1 for E.coli. Thus it is a clean green initiative combating the limitations of disinfection surpassing the existing barriers.
The aim of this study was to clarify the phytochemical property evaluation of Roselle plants grown under bio Azotobacterine (Azotobacterchroococcum) and phosphorein (Bacillus polymyxa) and mineral (N, P and K fertilizers at the rates of 25, 50 and 100% from the doses recommended by Ministry of Agriculture) fertilizers applied in different types of soil. Samples of Roselle plants were obtained from different soils (clay soil at Dar El-Ramad farm, sandy loam and saline loamy sand soil at Demo farm, Faculty of Agriculture) at El-Fayoum governorate conditions. Moreover, some of the phytochemical properties (N, P and K percentage in roselle herb and its uptake, photosynthetic pigments (chlorophyll A, chlorophyll B and carotenoids), anthocyanin pigment and pH value) of roselle plants (Hibiscus sabdariffa, L.) under different soils were determined. The data obtained showed that, bio and mineral (NPK) fertilizers increased the above compositions of roselle plants under different soils of experiment. The maximum increase of these compositions was obtained by the treatment clay soil × 100% NPK + bio fertilizers, followed by clay soil × 50% NPK + bio fertilizers as compared to saline loamy sand soil × non fertilizer treatment, although, the differences between these treatments and mineral fertilizer at the rate of 100% NPK alone were insignificantly. Therefore, it is economically and environmentally recommended to inoculate roselle seeds with mixture of Azotobacter + Bacillus and fertilize these inoculated plants with 50% NPK for improve chemical compositions (N, P and K percentage in roselle herb and its uptake, photosynthetic pigments (chlorophyll A, chlorophyll B and carotenoids), anthocyanin pigment and pH value) of roselle plants under clay soil. Key words: Roselle, Hibiscus sabdariffa L., nitrogen, phosphorus, potassium, biofertilization, soil type, salinity, chemical composition.
Plants are reservoirs of bioactive compounds with the potential for pharmaceutical use. In this study, the secondary metabolites of Neonauclea formicaria leaf crude ethanolic extract were determined using phytochemical screening. The plant's leaf extract was then used to test its angiogenesis activity using the chorioallantoic membrane (CAM) assay. Four concentrations of the extract were prepared—0.1 mg/L, 1.0 mg/L, 10.0 mg/L, and 100.0 mg/L and were topically applied on the CAM. Phytochemical screening revealed that N. formicaria leaves contain heavy amounts of flavonoids and tannins, while alkaloids, saponins, and steroids were present in trace amounts. The crude ethanolic extract was anti-angiogenic, as indicated by the significant decrease of vascular density at higher concentrations (P<0.05). The 100 mg/L extract concentration showed the highest vascular inhibition (50.93%) among the other concentrations, suggesting its angiopreventive potential (P<0.05). Further investigation on the embryo's gross morphometry revealed no significant effects in the weight, crown-rump length, head-beak length, forelimb length, and hind limb length. Also, these indices were not associated with the angiogenesis activity on the CAM. Further studies exploring the specific metabolites of the different plant parts of N. formicaria and the plant's angiopreventive potential are recommended.
The role of spatial variables, soil properties and overstorey structure in spatial variation of the herb-layer community in a riparian mixed forest was shown. The research were conducted in the "Dnipro-Orils’kiy" Nature Reserve (Ukraine). The research polygon was laid in a forest in the floodplain of the River Protich, which is a left inflow of the River Dnipro. Plant abundance was quantified by measuring cover within experimental polygon. The experimental polygon consisted of 7 transects and each transect was made up of 15 test points. The distance between rows in the site was 3 m. At the site we established a plot of 45×21 m, with 105 subplots of 3×3 m organized in a regular grid. Vascular plant species lists were recorded for each 3×3 m subplot along with visual estimates of species cover projection. The plant community was represented by 43 species, of which 18.6% were phanerophytes, 39.5% were hemikriptophytes, 9.3% were therophytes, 7.0% were geophytes. An overall test of random labelling revealed the total nonrandom distribution of the tree stems within the site. Constrained correspondence analysis (CCA) was applied as ordination approach. The forward selection procedure allowed us to select 6 soil variables, which explain 28.3% of the herb-layer community variability. The list of the important soil variables includes soil mechanical impedance (at the depth 0–5, 30–35, 75–80, and 95–10 cm), soil moisture, and soil bulk density. The variation explained by pure spatial variables is equal to 11.0 %. The majority of the tree-distance structured variation in plant community composition was broad-scaled. The significant relationship was found between the pure spatial component of the community variation and a lot of phytoindicator estimations of which the variability of damping and humidity were of the greatest importance. Trees stand was demonstrated to be a considerable factor structuring both the herb-layer community and spatial variation of the physical properties of soil.
Butterflies are the sensitive insects which react quickly to any kind of disturbances like changes in the habitat quality and environmental variation. Apart from pollinators they play a major key role in food chain, being prey for birds, reptiles, spiders and predatory insects. It is one of the most important assemblages of insects that act as biodiversity indicators as well as nature's gardeners. The objective of the present survey is focussed on the assessment of the diversity and abundance of butterfly conservation priorities in the study area. A total of 33 species of butterflies under 5 families and 26 genera were recorded during from December 2017 to February 2017 in the Kalimahal College campus, Sembarnarkoil, Tharangambadi Taluk. Nymphalidae was recorded as the most dominant family in terms of number of species (13) and number of genera (9), followed by Pieridae 8 species (6 genera), Lycaenidae 6 species (5 genera), Hesperiidae 3 species (3 genera), and Papilionidae 3 species (2 genera). Species richness (25), Simpson diversity index (0.7206) and Shannon 'H' index (1.783) were high in the month of December 2017. Simultaneously the Dominance index (0.6634) and Species Evenness (0.2871) were high in the month of February 2018. The outcomes of the present study highlight the importance of institutional campuses as a preferred habitat for butterflies. If the landscaping and maintenance of gardens are cautiously planned, the diversity of butterflies may increase in college campus providing a rich ground for butterfly conservation as well as for research.
The aim of this study was to evaluate the economics and toxicological aspects of pesticide management practices for sustainable chickpea production. The results of this study demonstrated that the average usage of pesticides is 877.30 g per hectare as an active ingredient in the chickpea growing. The average usages per hectare of active ingredient of insecticides, fungicides, and herbicides were calculated to be 1.50 g, 638.80 g, and 237.00 g, respectively. Fungicides are the biggest pesticide group used with 72.81% of total weight of active ingredients. It was calculated that the crop protection cost was EUR 75.65 per hectare, having the portion of 12 % of average production cost. The study revealed that the most common pesticides used by the farmers in chickpea growing were moderately hazardous and non-acute hazard categories. Based on the results of this study, it is suggested that the government should carry out effective agro-environmental intervention policies and farmer extension programs should be aimed at balancing the amounts of pesticides used per hectare for the sustainable, dynamic environment and prevention of pesticide toxicity. Keywords: chickpea, pesticide practices, economic, toxicological, Turkey
Experiments were conducted in 2015/2018 in two cacao plots established in 2012 and 2013 in Akure, Nigeria to investigate micro-climate conditions, weed densities, flowering and yield of cacao as affected by shade regimes. Established cacao plots under three plantain (Musa spp) shade regimes consisting of No-shade, Moderate and Dense shade were used. Air and soil temperature, relative humidity and Photosynthetic Active Radiation (PAR), weed population and species diversity, cacao flowering and pod production were measured. From the results, air and soil temperature measurements under No-shade plots had a significantly higher mean values (32°C) and soil (28°C) compared with moderately shaded [air, 30°C and soil, 26.5°C] and densely shaded [air, 30°C and soil, 26°C] plots in2015 and 2016 measurements but under 2017 measurements, no significant difference in the soil temperature of the plots under dense shade, moderate and the no-shade which were ascribed to canopy close-up of the cacao that led to reduced transmitted light through the canopy to the understories species. The vigour of weeds under no-shade plots were significantly higher compared with dense and moderately shaded plots. In 2013 established cacao plot, flower production was higher significantly in no-shade compared with those in moderate and dense shaded cacao plots in 2015 and 2016 measurement. Pod production under No-shade were significantly higher compared with other treatments in 2016 and 2017. Cherelle wilt rate was higher in shaded plots compared with the no-shade plots. Pod yield parameters were significantly higher under No-shade plots compared with shaded treatments during the three years of data measurement. Air temperature between 30°C to 33.7°C during flowering and fruit/pod setting was found to have positive influence on bean yield in cacao. The study concluded that excessive shade decreases yield of cocoa, while increases in temperature and relative humidity boosts some physiological processes for pod production in Cocoa
In order to study the relation between seasonal changes in phenolic compounds and flower opining date according to chilling requirements. The early and late-opining apple varieties, Barkhar, Local and Strakhan (Malussylvestris) were used. This study investigated variations in chilling requirements, bud burst and development in early and late varieties of apple trees. Results showed less bud burst in late varieties than in early ones. In the former, there were increased in phenolic compounds (conjugated and total phenols) at budburst in all varieties. As dormancy begins, free phenols are increased, coinciding with a reduction in the levels of conjugated phenols. Consequently, as dormancy breaks, these free phenols are conjugate with organic constituents, and a decrease in the concentrations of free phenols occurs, in order to reduce inhibitory effect on growth. We conclude that late varieties (Strakhan) are less economical in manufacturing new growth, as indicated by less bud vigor at budburst than early varieties (Barkhar and local) and show a marked differential phenols compound pattern throughout bud development compared to early varieties.
It is postulated that the presence of nypa palm (Nypa palm) in mangrove forest affect the reproductive function of fish by inhibiting the growth of macro invertebrates. The impact of Nypa fruticans (Wurmb) and mangroves on the benthic macro invertebrate community of Andoni River was carried out between January and August, 2017. A total of four stations were chosen based on nypa palm and native mangrove species’ presence and absence, station 1 (Open water), Station 2 (Nypa palm dominance), station 3 (Rhizophora and Avicennia dominance), Station 4 (Mixed). Results of water quality parameters include; pH 6.99±0.16, Temperature 28.20±0.05°C, DO 4.71±0.18mg/L, Conductivity 19.52±0.20µm/s, Salinity 10.76±0.07ppt, TDS 13.45±0.27ppt. Mean values of the physico-chemical parameters (P > 0.05) were not significantly different. Twelve taxa of benthic macro-invertebrates in eleven families were collected. The crustaceans were more in diversity (38.46%), while bivalvia, pisces and oligochaete had the least percentage composition (7.69%). The gastropods were more in species dominance (44.69%), while the Oligochaeta were least in abundance (0.61%). Shannon Weiner’s index across the stations for benthos was highest in station 2 (1.840) and lowest in station 1 (1.103). Simpson’s index was highest in station 2 (1.990) and lowest in station 1 (1.938). Pielou’s index of evenness was highest in station 2 (0.767) and lowest in station 1 (0.616). All the macro-invertebrates recorded were clean water and pollution tolerant species, and showed no significant difference across stations (P>0.05). In conclusion this study indicates that nypa palm does not affect the proliferation of macro invertebrates, which supports fishery population along the food chain.
Chilling is one of the major abiotic stress which limites yield and quality of many crops. The seedlings of rice varieties namely Koshihikari (Japonica subtype) chilling tolerant, and the susceptible NMR2 (Indica subtype) were treated at 25/15 °C and 5/4 °C day/night to determine the growth parameters, phenolic contents, and antioxidant activity. It was found that in all treatments, the growth of MNR2 including root and shoot lengths, and leaf and root weights were inhibited at greater levels than Koshihikari. There were seven phenolic acids identified in leaves of Koshihikari including caffeic acid, vanillin, ferulic acid, sinapic acid, benzoic acid, ellagic acid, and cinamic acid, but only benzoic acid and ellagic acid were found in leaves of MNR2. In contrast, only vanillic acid and ellagic acid were observed in roots of Koshihikari, whilst ellagic acid and cinnamic acid were found in roots of MNR2. It was found that rice reduced amount of phenolic acids but promoted quantity of total phenolic content (TPC) and total flavonoid content (TFC) and level of antioxidant activity in chilling stress, although the level of responses varied between Japonica and Indica subtypes. Tolerant rice possessed greater bound flavonoids, phenolics and phenolic acids, but susceptible rice accumulated greater free TPC and TFC in reduced temperature. Findings of this study highlighted that phenolic constituents in bound forms of phenols, polyphenols, and flavonoids may play an active role in rice plants than phenolic acids under chilling stress but need further elaboration.
Nematodes are plant-parasitic organisms that cause alterations in the chemical and physical environment of soils. This study investigates the relationship between nematode occurrence and some soil parameters. The results showed that the proportion of nematodes in soil was negatively correlated with soil pH (r2= 0.89); however, it increased with increasing electrical conductivity (EC) (r2 = 0.95), soil moisture (SM) (r2 = 0.60), and organic matter (OM) content (r2= 0.78). A positive correlation was found between the proportion of nematodes in the roots and the amount of coarse sand, while a negative correlation existed between the proportion of nematodes and the amount of fine sand, clay, and silt. The degree of colonization by nematodes increased with increasing coarse sand content (r2= 0.91). Conversely, the soil nematode population decreased with increasing fine sand content (r2= 0.83), clay (r2= 0.80), and silt content (r2= 0.97). The nematode population in banana roots correlated with soil phosphorus (r2 = 0.88), potassium (r2 = 69), calcium (r2 = 0.78), and magnesium levels (r2=0.78). Conversely, a negative correlation was found between nitrogen concentration and the nematode population in banana roots (r2=0.76). Overall, the population of nematodes in soil affects its pH, EC, SM, and OM content.
