Cyanobacteria in alkaline soil and the effect of cyanobacteria inoculation with pyrite amendments on their reclamation

The succession of cyanobacteria was studied in a usar (alfisol, solonetz, alkaline) soil, located in a tropical region of upper Gangetic plain, following the first rainfall for a period of 10 months (i.e., July–April). A dozen cyanobacteria were identified to grow on the soil surface and their appearance was in the following order: Microcoleus sp., Calothrix brevissima, Scytonema sp., Cylindrosprmum licheniformae, Cylindrosprmum fertilissima, Nostoc calcicola, Nostoc punctiformae, Aphanothece parietina, Nostoc commune, Aulosira fertilissima, Phormidium sp., and Oscillatoria sp. Among these cyanobacteria, N. calcicola was the dominant species. N. calcicola was inoculated on the alkaline soil and incubated under ambient conditions in the light for 2 years in the laboratory. Changes in soil properties were more rapid after the incorporation of pyrite (FeS₂). Recovery was monitored by using a filamentous heterocystous cyanobacterium N. calcicola and its bicarbonate-resistant (HCO₃^–R) mutant. The mutant strain showed better response to modification of soil pH following growth in soil.     

Tolerance of Drought and Temperature Stress in Relation to Increased Antioxidant Enzyme Activity in Wheat

An experiment was conducted with three wheat genotypes differing in their sensitivity to moisture and/or temperature stress to study the relationship of the chloroplast antioxidant system to stress tolerance. Both moisture stress and temperature stress increased glutathione reductase and peroxidase and decreased membrane stab-iltty, chlorophyll content and chlorophyll stability index in all genotypes. Under moisture stress. DL 153–2 showed the highest membrane stabihty index, chlorophyll content, chlorophyll stability index, glutathione reductase activity and peroxidase activity. However, under elevated temperature conditions, HD 2285, and to a lesser extent DL 153–2, showed higher membrane stability, chlorophyll content and chlorophyll stability index and activities of glutathione reductase and peroxi-dase. Raj 3077, which is sensitive to both drought and temperature stress, showed the lowest membrane stability, chlorophyll content and chlorophyll stability index and glutathione reductase and perosidase activity under elevated temperature as well as drought conditions. Thus, it can be concluded that tolerance of the genotype to moisture and/or temperature stress is closely associated with its antioxidant enzyme system.     

Genetic divergence in parental genotypes and its relation with heterosis, F1 performance and general combining ability (GCA) in opium poppy (Papaver somniferum L.)

Summary Genetic divergence in 110 population (20 parents and 90 F₁ hybrids) of opium poppy was studied by multivariate analysis. All the entries were grouped in 14 clusters. Out of 20 parents, ten were accumulated in one cluster and rest 10 distributed over seven clusters. Estimates of cluster distance showed that maximum intra-cluster distance was in -cluster IX (25.62) followed by cluster I (22.41), V (22.23) and IV (21.06). The inter cluster distances varied from 16.62 (between cluster XII and XIV) to 195.10 (between cluster IV and IX). The cluster analysis indicated substantial diversity among the parental genotypes, which had the potential to release considerable variation in their crosses. The first four principal components (PCs) with eigen values >1 accounted for 68% of variation among the population. The first and second components could account for 29 and 20% of the total morphological and alkaloidal variations, respectively. The PC1 was closely related to yield and yield related traits. The characters contributing greatest positive weight on PC1 were opium yield, plant height, stem diameter, capsule weight/plant and seed yield/plant. The possibilities of relationship between genetic divergence, F₁ performance, heterosis and GCA of parents have been explored.     

Evaluation of foliage yield and leaf quality traits in Chenopodium spp. in multiyear trials

Stability of foliage yield and its quality components has not been investigated in vegetable chenopods due to their underutilized status. The objectives of the present study were to assess genotype-environment interactions (GEI), determine stability of yield and quality components and to compare different parametric and non-parametric stability parameters. The present study reports for the first time the effect of genotype and environment on foliage yield and three leaf quality traits viz. carotenoid, ascorbic acid and protein content in different species of Chenopodium. Twenty accessions comprising four species were tested in a randomized block design with three replications across four environments. For all the four traits the largest sum of squares was accounted for by the genotypes, followed by GEI and environments. Highest foliage yield of 16.02 q/ha was obtained from C. album PRC 9804, while the lowest was from C. album CHEN 63/80 (4.01 q/ha). Many indigenous accessions of C. album (PRC 9801, IC 107299, ‘Chandigarh’, ‘local’ and ‘NEFA’) were unstable both for foliage yield and most of the quality traits. Most of the exotic accessions of C. giganteum were both stable and high yielding, thus, reflecting the potential of these accessions for future breeding programs/variety release.     

Restitution of thyroid activity in the DDT exposedSarotherodon Massambicus: A histological and histochemical profile

The histological and histochemical changes in the thyroid gland ofSarotherodon mossambicus after treatment for a period of 20 days with 0.001 ppm DDT (50% Tafarol, Dichlorodiphenyltrichloroethane) and the pattern of recovery were observed. The observations revealed a trend of increased follicular height, nuclear diameter andE/T ratio (ratio between the weight of total epithelial height and total follicular weight) significantly (p < 0.001) to that of the normal control. The gland turned considerably goitrous and nonfunctional. The colloid was vacuolated and mostly exhausted since most of the follicles were in acolloidal state with obliterated lumina. PAS, alcian blue, toluidine blue, Sudan black B and luxol fast blue tests also reveal negative reaction in thyroid of treated animals. The fish treated for 20 days with DDT were transferred to pesticide free water for 30 days, this resulted in restitution of thyroid structure to a normal state. The goitrous and hypertrophied follicles attain almost similar organization to that of normal control. The different parameters showed gradual changes during 10, 20, and 30 days of recovery. The histochemical tests also exhibit a gradual increasing pattern of different constituents up to the 30th day.     

Micronutrients (Fe,Mn, Zn and Cu) balance under long-term application of fertilizer and manure in a tropical rice-rice system

Purpose

The balance of micronutrients in soils is important in nutrient use efficiency, environmental protection and the sustainability of agro-ecological systems. The deficiency or excess of micronutrients in the plough layer may decrease crop yield and/or quality. Therefore, it is essential to maintain appropriate levels of micronutrients in soil, not only for satisfying plant needs in order to sustain agricultural production but also for preventing any potential build-up of certain nutrients.

Materials and methods

A long-term fertilizer experiment started in 1969 at Central Rice Research Institute, Cuttack, Odisha, India. Using this experiment, a study was conducted to analyze the balance of micronutrients and their interrelationship. The experiment was composed of ten nutrient management treatments viz. control; nitrogen (N); N + phosphorus (NP); N + potassium (NK); nitrogen, phosphorus and potassium (NPK); farmyard manure (FYM); N + FYM; NP + FYM; NK + FYM; and NPK + FYM with three replications. Micronutrients in soil (total and available), added fertilizers and organic manures and in rice plant were analyzed. Besides, atmospheric deposition of the micronutrients to the experimental site was also calculated. A micronutrient balance sheet was prepared by the difference between output and input of total micronutrients.

Results and discussion

Application of FYM alone or in combination with chemical fertilizer increased the diethylenetriamine pentaacetate (DTPA)-extractable Fe, Mn and Zn over the control treatment. The treatment with NPK + FYM had the highest soil DTPA-extractable Fe, Mn, Zn and Cu after 41 years of cropping and fertilization. Application of chemical fertilizers without P decreased the DTPA-extractable Zn over the control while the inclusion of P in the fertilizer treatments maintained it on a par with the control. The application of P fertilizer and FYM either alone or in combination significantly increased the contents of total Fe, Mn, Zn and Cu in soil mainly due to their micronutrient content and atmospheric depositions. A negative balance of Zn was observed in the N, NP, NK and NPK treatments, while a positive balance observed in the remaining treatments. The balance of Mn was negative in all the treatments, due to higher uptake by the rice crop than its addition.

Conclusions

Long-term application of chemical fertilizers together with FYM maintained the availability of micronutrients in soil and, thus, their uptake by rice crop.

     

Influence of earthworm culture on fertilization potential and biological activities of vermicomposts prepared from different plant wastes

The present investigation was aimed to analyze influence of earthworm culture on nutritive status, microbial population, and enzymatic activities of composts prepared by utilizing different plant wastes. Vermicomposts were prepared from different types of leaves litter of horticulture and forest plant species by modified vermicomposting process at a farm unit. Initial thermophilic decomposition of waste load using cow‐dung slurry was done in the separate beds. The culture of Eisenia fetida was used for vermicomposting in specially designed vermibeds at the farm unit. The physico‐chemical characteristics, enzyme activities (oxido‐reductases and hydrolases), and microbial population (bacteria, fungi, free‐living nitrogen‐fixing bacteria, actinomycetes, Bacillus, Pseudomonas, phosphate‐solubilizing bacteria and fungi) of vermicomposts were found significantly higher (p < 0.05) than those of control (without earthworm inoculum). The study quantified significant contributions of earthworm culture to physico‐chemical, enzymatic, and microbiological properties of vermicompost and confirmed superior fertilization potential of vermicompost for organic farming. The agronomic utility of vermicompost was assessed on yellow mustard plant in a pot experiment. Pot soil was amended with different ratios (5%, 10%, 20%) of vermicompost and normal compost (without earthworm inoculum). Effects of these amendments on the growth of Brassica comprestis L. were studied. The significant differences (p < 0.05) in the growth of plant were observed among vermicompost‐, compost‐amended soil, and control. Vermicompost increased the root and shoot lengths, numbers of branches and leaves per plant, fresh and dry weights per plant, numbers of pods and flowers, and biochemical properties of plant leaf significantly, especially in 20% amendment. These results proved better fertilization potential of vermicompost over non‐earthworm‐inoculated compost.     

低压低成本滴灌系统的设计、构造与评估(摘选)

使用当地产材料,包括KB管、KB压力脚踏泵、带有微型管的压力桶以及医用输液管开发了手动控制低压低成本( LPLC)滴灌系统.对该装置进行了田间试验,并且针对西红柿与椰菜,对该系统的各种独立参数,如营养生长、水力性能、农作物需水量、水分利用效率以及经济成本从不同方面进行了评估.该系统的投资回收期为1个季度,效益成本比为1...     

Biomass allocation strategies and productivity of tropical trees related to successional status

The productivity and biomass allocation strategies of two early successional (ES) and two late successional (LS) tropical tree species were compared and related to their successional status. Apart from distinct differences in clean bole length, crown depth, maximum crown width and leaf area index (LAI), the ES species showed higher allocation to the shoot, particularly to the bole, whereas the LS species had higher allocation to the root. The ES species with shallow root system had more root biomass within the upper 20 cm of the soil profile while the LS species with deeper roots had a higher proportion of root biomass distributed below the 20 cm depth. The productivity of the shoot of ES species was significantly higher than that of LS species. However, root productivity for ES species was higher only up to 4 years of age; the differences were not significant between 5 and 7 years. The implication of these results for agroforestry and mixed plantation forestry is emphasized.     

Studies on the effect of dry Sundakai (solanum torvum) powder supplementation on lipid profile,glycated proteins and amino acids in non-insulin dependent diabetic patients

The effect of dry Sundakai powder supplementation (7 g providing 1.23 g of crude fibre) on glycemic control, lipidemic control, total amino acids and uronic acid was studied on 30 non-insulin dependent diabetes mellitus patients. All the patients were on hypoglycemic drugs. The above parameters were monitored at day 1, 15 and 30 days. After one month of fibre supplementation, no significant changes were observed with respect to glucose, lipid profile, glycated proteins, total amino acids and uronic acid levels in these subjects.