GIS-based assessment of non-equilibrium pattern between groundwater recharge and irrigation draft in a semi-arid region of Rajasthan,India

Over-exploitation of groundwater for irrigation can result in drastic reduction in groundwater level in Jodhpur district of western Rajasthan, India. In this study, we used the long-term trend analysis of seasonal groundwater level data to predict the future groundwater scenario in 33 villages of Jodhpur district, assessed the impact of water harvesting structures on groundwater recharge and explored the non-equilibrium between groundwater recharge and irrigation draft in the study area. Analysis of groundwater level data from 26 observation wells in 33 villages in the pre-monsoon period showed that groundwater level decreased continuously at the rate of 2.07 m/a. With this declining rate, most of the tube wells(including the well with the maximum depth of 193 m) are predicted to become completely dry by 2050. Behavior of temporal groundwater level data in the study period(from 2004 to 2012) can be explained by different geospatial maps, prepared using Arc GIS software. Statistical analysis of the interpolated maps showed that the area with the maximum positive groundwater recharge occupied 63.14% of the total area during 2010–2011 and the area with the maximum irrigation draft accounted for 56.21% of the total area during 2011–2012. Higher groundwater recharge is attributed to the increase in rainfall and the better aquifer condition. Spatial distribution for the changes of average groundwater recharge and draft(2008–2009 and 2011–2012) showed that 68.50% recharge area was in positive change and 45.75% draft area was in negative change. It was observed that the area of the irrigation draft exceeded that of the groundwater recharge in most of the years. In spite of the construction of several shallow water harvesting structures in 2009–2010, sandstone aquifer zones showed meager impact on groundwater recharge. The best-fit line for the deviation between average groundwater fluctuation due to recharge and irrigation draft with time can be represented by the polynomial curve. Thus, over-exploitation of groundwater for agricultural crops has result in non-equilibrium between groundwater recharge and irrigation draft.     

Fractions of Manganese in Soil under Long-Term Experiment and Their Contribution to Manganese Availability and Uptake by Maize-Wheat Cropping Sequence

Manganese (Mn) is an essential micronutrient needed for plant growth and development, but it can be toxic to plants in excess amounts. Long-term fertilizer experiment and intensive cropping alter the soil properties and also affect its plant-available Mn contents. To understand the dynamics of Mn under long-term fertilizer experiment the present study was initiated during 1972 at the experimental farm of College of Agriculture, CSK HPKV, Palampur (32° 6′ N latitude and 76° 3′ E longitude) in a randomized block design with 11 treatments replicated three times with a maize-wheat cropping sequence. The soils of the experimental area in the beginning of the experiment were acidic in reaction and taxonomically classified as Typic Hapludalfs. Surface (0.0–20 cm) and subsurface (20–40 cm) soil samples taken after the harvest of maize (kharif, 2008) were analyzed for pools of Mn and chemical indices of soil quality using standard analytical methods. Besides, the pools of Mn were also determined in the composite soil samples drawn from adjacent fallow plots. Results showed that all the pools of Mn were noticeably greater in farmyard manure (FYM)–amended plots compared to zero-fertilized plots. Although the residual fraction was found to be the most dominant fraction, organically bound and exchangeable forms were found to play major roles in the nutrient supply, crop productivity, and nutrient uptake. The greatest productivity of maize (2008) and wheat (2008–09) was recorded under the 100% nitrogen, phosphorus, and potassium (NPK) + FYM treatment. FYM and lime treatments resulted in significantly greater uptake of all the nutrients by both the crops compared to other treatments. The organically bound fraction was found to have the greatest significant and positive correlation with yield and nutrient uptake of maize and wheat crops. Further regression analysis studies revealed that the organic form was the most important pool contributing towards the variation in the parameters. Exchangeable and organically bound forms contributed significantly towards diethylene triamine pentaacetic acid (DTPA)–extractable Mn.     

Population genetic structure of <Emphasis Type="Italic">Rhizoctonia solani</Emphasis> AG1IA from rice field in North India

Rhizoctonia solani AG1IA is an important fungal pathogen causing significant yield and quality losses in rice production. However, little is known about the levels of genetic diversity and structure of this pathogen in North India. Out of 240 samples collected from different rice-growing regions of North India, 112 isolates were identified as R. solani AG1IA subgroups using species-specific primers. All 112 isolates were organized into four groups on the basis of percent disease index (PDI). The majority of the isolates were weakly virulent. Population genetic analysis was performed within and between populations using inter simple sequence repeat (ISSR) markers. A total of 8249 alleles were identified from the 112 isolates of R. solani AG1IA through analysis of the ten inter simple sequence repeat markers. All the ten ISSR markers were polymorphic. The average number of bands per primer was 7.3 which ranged in size from 250 to 1500 bp. Genetic structure of the isolates using inter simple sequence repeat primers showed high degree of polymorphism (PIC ≥0.81). The analysis of molecular variance (AMOVA) indicated that most of the genetic diversity occurred within populations (60%), while the variability among populations and among regions contributed 25 and 15%, respectively. Overall, the present study reveals that a large variation exists among rice-infecting isolates of R. solani AG1IA in North India. Fingerprinting of the isolates using ISSRs along with phenotypic characterization and virulence analysis will help epidemiological studies that can provide new insights into pathogen biology and disease spread.     

Foliar spray of mineral nutrients enhanced the growth,seed yield,and quality in onion (Allium cepa L.) cv. Pusa Riddhi

The present experiment was conducted to investigate the effect of foliar spray of mineral nutrients on plant growth, seed yield, and quality attributes in onion cv. Pusa Riddhi at SPU, IARI, New Delhi during rabi 2013–14 and 2014–15. The experiment consisted of 16 treatments comprised of boron, zinc, calcium, and magnesium laid out in a completely randomized block design with two replications. The study revealed that the foliar zinc spray (625 g ha^?1) produced higher seed scape height (105.35 cm) along with lower disease incidence (8.50%) than the other treatments. Whereas, higher number of seed scapes plant^?1 (11.20) and productive seed scapes plant^?1 (8.58) were observed in T₁₀ (500 g ha^?1) and combined spray of B + Zn + Ca (T₁₄), respectively. The flowering traits, viz., umbellates umbel^?1 (642.45), productive umbellates umbel^?1 (579.35), and umbel diameter (7.38cm) were significantly (p ≤ 0.05) higher in T₁₅ than other treatments. Similarly, higher seed yield and seed quality attributes were also observed in combined application of all minerals treatment (T₁₅).     

In-vivo therapeutic efficacy trial with artemisinin derivative, buparvaquone and imidocarb dipropionate against Babesia equi infection in donkeys

The therapeutic efficacy of imidocarb, artesunate, arteether, buparvaquone and arteether+buparvaquone combination was evaluated against Babesia equi of Indian origin in splenectomised donkeys with experimentally induced acute infection. Efficacies of these drugs were tested by administering each drug or drug combination to groups of donkeys (having three donkeys each group). One group of donkey was kept as untreated control for comparing the results. Parasitaemia, haematology (WBC, RBC, PCV, granulocytes and haemoglobin), biochemical parameters (SAST, SALT, alkaline phosphatase, albumin/globulin ratio) were monitored at regular intervals. Individually, arteether and buparvaquone were found to have no parasite clearing efficacy and the treated animals died within 5-6 days after showing high parasitaemia and clinical symptoms of the disease. However, artesunate treated animals were able to restrict the parasite multiplication but only during the treatment period. Animals treated with imidocarb and arteether+buparvaquone combination were able to clear the parasite from the blood circulation after 2-5 days post-treatment (PT). After 55-58 days PT, recrudescence of B. equi parasite was observed in both these groups and a mean survival period of 66 days and 69 days, respectively, was recorded in these groups. Results of haemato-biochemical parameters had shown that imidocarb had deleterious effect on the liver function while on the other hand arteether+buparvaquone combination was found to be safe. This limited study indicates that arteether+buparvaquone combination could be a better choice than imidocarb for treating B. equi infection, but further trials are required in detail.     

Angiostrongylus vasorum infection in 2 dogs from Newfoundland

Described are the first antemortem diagnosis made via fecal examination using the Baermann technique and the first postmortem recovery of endemic Angiostrongylus vasorum in dogs from North America, specifically the Avalon peninsula of Newfoundland. In one dog, A. vasorum was recovered and identified at postmortem; gross and histologic lesions are described.     

A simple method for large-scale propagation of Dendrocalamus asper

The influence of position of cuttings, auxin treatments and seasonal variation on adventitious rooting of Dendrocalamus asper, a multipurpose edible bamboo of horticultural value, was examined. Single node proximal (culm) and distal (culm-branch) cuttings were collected during the months of April–June and treated for 24 h with water or 2 mM auxin (indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and naphthalene acetic acid (NAA)). The treated cuttings were planted horizontally in sand beds and maintained under misting conditions for 2 months. Culm cuttings exhibited better adventitious rooting than culm-branch cuttings and the month of May proved to be the best for rooting of both types of cuttings. Auxin treatments also influenced adventitious rooting and their effectiveness was in the order: NAA>IBA>IAA. The interaction among auxin, position of cuttings and month of collection was also found to be significant on root induction and differentiation. Single node culm cuttings, without auxin treatment, resulted in 98% plantlets in May and 67% plantlets in June, and emerged as a suitable material for large-scale vegetative propagation. Administration of IAA or NAA to abundant culm-branch cuttings of low commercial utility (collected in May) also produces ≥50% plantlets.     

Effect ofCuscuta infection on chloroplast lipid composition ofBrassica leaves

Brassica campestris was infected with the angiosperm parasite,Cuscuta reflexa, on 24 DAS (days after sowing). A significant reduction (43%) in carbon dioxide assimilation in leaves was found compared to normal plant, when both were assayed on 38 DAS. At this stage, the chloroplast lipid in infected leaves had decreased by 34%, with a reduction of 13, 38 and 55%, respectively, in neutral, glyco- and phospholipids. Among the glycolipids, the decrease in the content of MGDG, DGDG and SQDG was 21, 67 and 44%, respectively, with 2.4-fold increase in the MGDG/DGDG ratio. The chlorophyll content was reduced by 24%, while the carotenoid level increased by 44%. The free fatty acid content was enhanced by 47% which may be attributed to an increase in lipase activity. The contents of saturated fatty acids (capric, lauric, myristic, palmitic and stearic) increased while the contents of unsaturated fatty acids (palmitoleic, oleic, linoleic and linolenic) decreased. The ratio of unsaturated to saturated fatty acids decreased over 50%. These findings may suggest chloroplasts as reactive sites of the host-parasite interaction in case of the angiosperm parasite.Abbreviations DAS day after sowing - DGDG digalactosyl diglyceride - FAME fatty acid methyl esters - FFA free fatty acids - MGDG monogalactosyl diglyceride - SQDG sulfoquinovosyl diglyceride