Genetic Characterization of Indigenous Rice Varieties in Eastern Himalayan Region of Northeast India

The eastern Himalayan region of Northeast （NE） India is home to a large number of indigenous rice varieties, which are traditionally classified as Oryza sativa subspecies indica, japonica or intermediate types. The classification based on traditional Cheng’s index is often inconclusive due to phenotypic plasticity of morphological characters, which are influenced by environmental conditions. We used molecular markers specific for indica and japonica subspecies to assess the degree of genetic relatedness of indigenous rice varieties in NE India. The results revealed that majority of upland （jum） and glutinous rice varieties, traditionally considered as japonica, were genetically close to the subspecies indica. All varieties of boro ecotype were found to be indica type, and only a few varieties cultivated in lowland and upland areas were japonica type. Some of the lowland varieties of the sali ecotype were intermediate between indica and japonica, and they showed a closer genetic affinity to O. rufipogon.     

磷和钾对巴基斯坦西北部向日葵生长、产量的交互效应

Potassium (K) and phosphorus (P) applications improve growth, increase yield and yield components of sunflower (Helianthus annuus L.) on K and P deficient soils in Northwest Pakistan. A field experiment was conducted using sunflower cv. Hysun-33 at the New Developmental Research Farm of KPK Agricultural University, Peshawar, Pakistan, during summer 2006. The experimental design was a randomized complete block in split plot arrangements, with six levels of K (0, 25, 50, 75, 100, and 125 kg K ha^-1) as main plots and four levels of P (0, 45, 90, and 135 kg P ha^-1) as sub-plots with three replications. Sunflower yield and yield components responded positively to K and P fertilization but the magnitude of response varied with the levels of K and P. Days to flowering and maturity, grains per head, 1000-grain weight, shelling percentage, and grain yield increased tremendously in the K and P-fertilized plots as compared to the control with no K and P applied. The combined application of 100 kg K and 45 kg P ha^-1 significantly increased yield components, grain yield, harvest index, and shelling percentage of sunflower, suggesting that 100 kg K ha^-1 in combination with 45 kg P ha^-1 could maximize productivity of sunflower planted after wheat on the K and P deficient soils in the study area.     

在含盐新成土上施加有机肥和化学改良剂对土壤性质和作物产量的影响

A field experiment was conducted for two consecutive years in a farmer‘s field at Haji Mora Village, Dera Ismail Khan (D.I. Khan) in the Northwest Frontier Province (NWFP) of Pakistan to compare various management practices, such as the effect of various organic manures and gypsum in a rice-wheat cropping system on a saline-sodic Entisol (Zindani soil series). The treatments consisted of 1) a control (rice-wheat), 2) gypsum, 3) farmyard manure (FYM), 4) berseem (Trifolium alexandrinum L.) as green manure (GM), and 5) dhancha (Sesbania sp.) as GM. All treatments increased yields of both rice and wheat significantly (P (0.01) over the control, with the green manure treatments proving more economical than the others; while they decreased pH, electrical conductivity (EC), and sodium adsorption ratio (SAR) of the soil. Saturation percentage and available water of the soil were raised for all treatments due to an increase in organic matter content of the soil.     

ZERO TEST EMISSIONS OF SULPHUR DIOXIDE FROM LARGE COAL UNDER STAGED FLUIDIZED BED COMBUSTION

This paper reports the emissions of SO₂ from large coal under staged combustion without any additive. A stainless steel combustor, 2 m high and 0.3 × 0.3 m in cross section was used. Fluidizing air was supplied through a multihole distributor. An adjustable secondary air injector was used along the vertical axis of the combustor to introduce secondary air in the freeboard. From 0–40% of total air was injected in the freeboard above the bed. The experiments were carried out at fluidizing velocities of 1–2 m s^-1, bed temperatures of 1103–1153 °K, 20–40% excess air, and bed particle sizes of 665 μm. Bed temperature and level of air staging had the most significant effect on SO₂ emissions.     

INTERACTION OF BTPYRIDYLIUM HERBICIDES WITH ORGANO-CLAY COMPLEX

The adsorption of diquat (1,1′-ethylene-2,2′-bipyridylium dibromide) and paraquat (1, 1′-dimethyl-4,4′-dipyridylium dichloride) by an organo-clay complex has been investigated. Paraquat was adsorbed by the organo-clay complex in greater amounts than was diquat. Infrared studies suggest the formation of charge-transfer complexes between diquat or paraquat and the organo-clay complex. Organic matter upon interaction with clay may facilitate the adsorption of diquat and paraquat on clay minerals in soil.     

阴离子对应用于红壤中的微生物量的镉毒害的影响

A laboratory incubation experiment was conducted to elucidat the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels,i.e.,O(background),5,15,30,60 and 100μg g^-1 soil in the form of either cadmium acetate or cadmium chloride. Application of cadmium as cadmium acetate markedly reduced the soil microbial biomass carbon compared to cadmium applied as cadmium chlorde at all the tested levels.Similarly,organic carbon to biomass carbon ration in the soil was markedly increased by increasing the level of the cadmium in the soil as cadmium acetate,while the change wa much smaller in the case of cadmium chloride at the same cadmium levels.The results suggested that due consideration should be given to the source of cadmium while deciding the cadmium levles in experiments.     

An overview on biochar production, its implications, and mechanisms of biochar-induced amelioration of soil and plant characteristics

The degradation of soil fertility and quality due to rapid industrialization and human activities has stimulated interest in the rehabilitation of low-fertility soils to sustainably improve crop yield. In this regard, biochar has emerged as an effective multi-beneficial additive that can be used as a medium for the amelioration of soil properties and plant growth. The current review highlights the methods and conditions for biochar production and the effects of pyrolysis temperature, feedstock type, and retention time on the physicochemical properties of biochar. We also discuss the impact of biochar as a soil amendment with respect to enhancing soil physical (e.g., surface area, porosity, ion exchange, and water-holding capacity) and chemical (e.g., pH, nutrient exchange,functional groups, and carbon sequestration) properties, improving the soil microbiome for increased plant nutrient uptake and growth, reducing greenhouse gas emissions, minimizing infectious diseases in plants, and facilitating the remediation of heavy metal-contaminated soils. The possible mechanisms for biochar-induced amelioration of soil and plant characteristics are also described, and we consider the challenges associated with biochar utilization. The findings discussed in this review support the feasibility of expending the application of biochar to improve degraded soils in industrial and saline-alkali regions, thereby increasing the usable amount of cultivated soil. Future research should include long-term field experiments and studies on biochar production and environmental risk management to optimize biochar performance for specific soil remediation purposes.