Characterization of Lotus Stem (Nelumbo nucifera) Starches Purified From Three Lakes of India

Starch was isolated from lotus stem obtained from three lakes of Jammu and Kashmir, India, and their physicochemical, morphological, and pasting properties were studied. Protein, fat, and amylose content varied significantly (p ≤ 0.05) among the different starches, but no significant difference was found in ash content. Amylose content was highest in lotus stem starch from Manasbal (30.0%), followed by the Dal (28.3%), and the Wular (25.0%). Functional properties like swelling, solubility, and water absorption showed an increasing trend with an increase in temperature from 50–90°C. Scanning electron microscopy of lotus stem starches showed small rounded and typical oval shaped granules with a smooth surface. The starch extracted from Wular and Dal lotus stems had larger granules than Manasbal starch. All the starches obtained from the three sources gave a similar B-type X-ray diffraction pattern. Pasting properties—such as pasting temperature, peak viscosity, breakdown, setback, and final viscosity—significantly differed among starches.     

Analysis of potential yields and yield gaps of rainfed soybean in India using CROPGRO-Soybean model

To assess the scope for enhancing productivity of soybean (Glycine max L. Merr.), the CROPGRO-Soybean model was calibrated and validated for the diverse soybean-growing environments of central and peninsular India. The validated model was used to estimate potential yields (water non-limiting and water limiting) and yield gaps of soybean for 21 locations representing major soybean regions of India. The average water non-limiting potential yield of soybean for the locations was 3020 kg ha⁻¹, while the water limiting potential was 2170 kg ha⁻¹ indicating a 28% reduction in yield due to adverse soil moisture conditions. As against this, the actual yields of locations averaged 1000 kg ha⁻¹, which was 2020 and 1170 kg ha⁻¹ less than the water non-limiting potential and water limiting potential yields, respectively. Across locations the water non-limiting potential yields were less variable than water limited potential and actual yields, and strongly correlated with solar radiation during the season (R² = 0.83, p ≤ 0.01). Both simulated water limiting potential yield (R² = 0.59, p ≤ 0.01) and actual yield (R² = 0.33, p ≤ 0.05) had significant but positive and curvilinear relationships with crop season rainfall across locations. The gap between water non-limiting and water limiting potential yields was very large at locations with low crop season rainfall and narrowed down at locations with increasing quantity of crop season rainfall. On the other hand, the gap between water limiting potential yield and actual farmers yield was narrow at locations with low crop season rainfall and increased considerably at locations with increasing amounts of rainfall. This yield gap, which reflects the actual yield gap in rainfed environment, is essentially due to non-adoption of improved crop management practices and could be reduced if proper interventions are made. The simulation study suggested that conservation of rainfall and drought resistant varieties in low rainfall regimes; and alleviation of water-logging and use of water-logging tolerant varieties in high rainfall regimes will be the essential components of improved technologies aimed at reducing the yield gaps of soybean. Harvesting of excess rainfall during the season and its subsequent use as supplemental irrigation would further help in increasing crop yields at most locations.     

Biochemical composition and photosynthetic activity of Pongamia pinnata（L.） Pierre in response to acute 60Co γ-irradiation

To elucidate the potential and sensitivity of cirradiation in Pongamia pinnata,the present study has been done by irradiating the air-dried seeds to differentγ-irradiation doses(100 Gy,200 Gy,400 Gy and 600 Gy),using 60Co source.Significant increase(p≤0.05)in the germination,growth,and vigor was recorded under the100 Gy treatment than the control set.The chlorophylla and total chlorophyll content(mgg-1 FW)in the leaves of P.pinnata showed a significant decrease under the higher irradiation treatments(200 Gy,400 Gy and 600 Gy).In contrast,chlorophyllb showed a radio-resistance up to 200 Gy dose,and above which its concentration declined significantly(p≤0.05).Photosynthetic rate,stomatal conductance,intercellular CO2 concentration,and transpiration rate were stimulated by 100 Gy irradiation treatment and the higher doses inhibited these parameters.Antioxidant activity in the leaves of P.pinnata tended to increase after irradiation in a dose-dependent manner.All the plants under different treatments ofγ-irradiation showed stimulation in production of proline,flavonoid,and phenolic content in comparision to the control.The findings of the present study showed thatγ-irradiation treatment stimulates the secondary metabolite production(proline,flavonoid and phenolic)and favours faster growth of P.pinnata.     

Managing water in rainfed agriculture—The need for a paradigm shift

Rainfed agriculture plays and will continue to play a dominant role in providing food and livelihoods for an increasing world population. We describe the world's semi-arid and dry sub-humid savannah and steppe regions as global hotspots, in terms of water related constraints to food production, high prevalence of malnourishment and poverty, and rapidly increasing food demands. We argue that major water investments in agriculture are required. In these regions yield gaps are large, not due to lack of water per se, but rather due to inefficient management of water, soils, and crops. An assessment of management options indicates that knowledge exists regarding technologies, management systems, and planning methods. A key strategy is to minimise risk for dry spell induced crop failures, which requires an emphasis on water harvesting systems for supplemental irrigation. Large-scale adoption of water harvesting systems will require a paradigm shift in Integrated Water Resource Management (IWRM), in which rainfall is regarded as the entry point for the governance of freshwater, thus incorporating green water resources (sustaining rainfed agriculture and terrestrial ecosystems) and blue water resources (local runoff). The divide between rainfed and irrigated agriculture needs to be reconsidered in favor of a governance, investment, and management paradigm, which considers all water options in agricultural systems. A new focus is needed on the meso-catchment scale, as opposed to the current focus of IWRM on the basin level and the primary focus of agricultural improvements on the farmer's field. We argue that the catchment scale offers the best opportunities for water investments to build resilience in small-scale agricultural systems and to address trade-offs between water for food and other ecosystem functions and services.     

Quantification of Spatial Variability of Soil Physical Properties in a Lesser Himalayan Sub-Basin of India

Eurasian Soil Science - The quantification of spatial variability of soil properties is indispensable for evaluating the effectiveness of provisions undertaken to tackle various land surface...     

Analysis of herbal teas made from the leaves of comfrey (Symphytum officinale): reduction of N-oxides results in order of magnitude increases in the measurable concentration of pyrrolizidine alkaloids

OBJECTIVES: To determine the relative quantities of two hepatotoxic pyrrolizidine alkaloids, symphytine and echimidine, in teas prepared from comfrey leaves (Symphytum officinale), and to determine the potential contribution of the N-oxide forms of these alkaloids to levels of the parent alkaloids. DESIGN: Comfrey leaves were purchased from three commercial sources and used to prepare tea in a manner consistent with the methods used by consumers. An extraction scheme was devised for extraction of the alkaloids, and a gas chromatographic method was developed to quantify the two major alkaloids, symphytine and echimidine. Recognising that the N-oxide derivatives of these alkaloids have also been identified in comfrey preparations, chemical reduction was applied to determine the total quantities of the alkaloids as free bases and as N-oxide derivatives. RESULTS: The concentration of symphytine and echimidine varied considerably between teas prepared from leaves purchased from the different vendors of plant material. Moreover, a much higher concentration of symphytine was found in the tea when steps were included to reduce N-oxides prior to analysis. The treatment of pure symphytine with hot water did not generate the N-oxide derivative de novo. CONCLUSIONS: Since the pyrrolizidine alkaloids are known to be hepatotoxic, consumption of herbal teas made from comfrey leaves may be ill-advised. The concentration of pyrrolizidine alkaloids in such teas may be underestimated substantially unless the concentration of N-oxides is taken into consideration.     

Heavy-Metal Concentrations in Sediments Collected from ICRISAT Lake,Patancheru, India

To determine and characterize the initial background concentrations of heavy metals, a total of 50 sediment samples were collected from the largest lake at the International Crops Research Institute for the Semi-arid Tropics (ICRISAT) in Patancheru, India. The finely ground sediment samples were digested using a microwave-assisted digestion method and analyzed for 15 heavy metals using inductively coupled plasma–optical emission spectrometry (ICP-OES). The results showed that the concentrations of the heavy metals varied greatly with metal and sediment sample, but in general the concentrations were low. Our results suggest that the sediments from this lake (15 ha in area) at the ICRISAT center do not appear contaminated with the heavy metals evaluated, and they indeed reflect normal background concentrations of these metals released through the natural process of weathering.     

Induced chlorophyll mutations. I. Mutagenic effectiveness and efficiency of EMS, HZ and SA in mungbean

A systematic and comparative study on the frequency and spectrum of chlorophyll mutations induced by ethylmethane sulphonate (EMS) — an alkylating agent, hydrazine hydrate (HZ) — a base analogue and sodium azide (SA) — a respiratory inhibitor, was carried out in two mungbean varieties, namely, PDM-11 and NM-1. Awide spectrum of chlorophyll mutants was obtained in the M₂ generation. All these chlorophyll-deficient mutants were lethal except maculata, viridis and virescent. Chlorina followed by xantha types were predominant in both the varieties. EMS treatments induced the highest frequency of chlorophyll mutations followed by HZ and SA. The frequency of chlorophyll mutations was dose-dependent and increased with the mutagen concentration. Based on effectiveness in both varieties, the order of mutagens was HZ > SA > EMS. Two criteria viz., pollen sterility (Mp/S) and seedling injury (Mp/I) were taken into consideration to determine the efficiency of the mutagens. EMS was found to be the most efficient mutagen followed by HZ and SA. Moderate concentrations of the mutagens were the most effective and efficient in inducing mutations.