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11.
To find effective alternatives to reduce the application of conventional urea (CU), a conventional biofertilizer (CB) preparation (charcoal mixed Azotobacter chroococcum and Bacillus subtilis) and the same biofertilizers entrapped in an organic matrix consisting of cow dung, rice bran, dried powder of neem leaves, and clay soil in 1:1:1:1 ratio and 25% (w/w) saresh (plant gum of Acacia sp.), named as super granules of biofertilizers (SGBF) were applied to cultivate wheat (Triticum aestivum L. cv. ‘WH-711’) in experimental plots. The results revealed that the efficacy of commercially available charcoal mixed biofertilizers could not prove as effective alternative to CU, whereas the same dose of biofertilizers entrapped in the organic matrix, SGBF, resulted in a significant increase in growth and productivity of wheat. It appears that SGBF prepared and applied in this study is an effective organic alternative to the urea for wheat cultivation in semi-arid subtropical agro-ecosystems.  相似文献   
12.
The distribution and metabolic fate of [14C]maleic hydrazide in white ash and black locust seedlings were studied using high-performance liquid chromatography in conjunction with thin-layer chromatography and liquid scintillation spectrometry. Most of the maleic hydrazide was translocated to the leaves and stems of the black locust seedlings within 1 day after treatment but in the case of the white ash seedlings it remained in the stem tissue. After 30 days, the 14C was concentrated in the leaves of the black locust seedlings, but only in the stem and at the injection point of the white ash seedlings. Approximately 40 and 10% of the applied 14C was found at the injection points of the white ash and black locust seedlings, respectively. Chromatographic analysis of extracts showed no detectable metabolite in the black locust seedlings but two metabolites were detected in the white ash seedlings.  相似文献   
13.
The distribution and metabolic fate of [14C]-daminozide in silver maple and American sycamore seedlings were studied by use of autoradiography, ion-exchange chromatography, thin-layer chromatography (t.l.c.), and liquid scintillation spectrometry. Within one day after treatment with [14C]-daminozide, radioactivity was detected in all parts of the plant. The 14C concentrated in meristematic regions of the leaves. Ion-exchange and thin-layer chromatographic analyses of the 50% methanol extracts indicated that no detectable metabolites of daminozide were formed in any of the plant parts but approximately 20% of the applied 14C, most of it in the stem tissue, was not extractable by aqueous methanol.  相似文献   
14.
Field experiments were conducted to evaluate the effects of eco-friendly organic matrix entrapped urea (OMEU) on growth, productivity, and yield of rice (Oryza sativa L. cv. Basmati) and soil enrichment in the paddy field at Rohtak (Haryana) located near Delhi. The OMEU prepared in granular form contained cow dung, rice bran (grain cover of Oryza sativa), powder of neem leaves (Azadirachta indica), and clay soil (diameter of particles < 0.02 mm) in 1:1:1:1 ratios and saresh (plant gum of Acacia sp.) as binder along with half of the recommended dose of commercially available soluble urea (free urea; FU). Single basal application of OMEU showed an increase in plant growth in terms of fresh and dry weights, root length, root, leaf and tiller numbers, soluble protein, total N and ammonium in leaves, productivity in terms of grain and straw yield, and nutritional and microbial activities of field soil over free form of urea and no fertilizer application. Nutritional status of rice grains was also improved over the free urea and no fertilizer controls. Our data indicate that OMEU, which is low cost and based on bio-degradable, non-toxic, and locally available agro-waste, can be attempted to replace the conventional use of soluble urea in rice.  相似文献   
15.
Late blight is the most devastating disease of the potato crop that can be effectively managed by growing resistant cultivars. Introgression of resistance (R) genes/quantitative trait loci (QTLs) from the Solanum germplasm into common potato is one of the plausible approaches to breed resistant cultivars. Although the conventional method of breeding will continue to play a primary role in potato improvement, molecular marker technology is becoming one of its integral components. To achieve rapid success, from the past to recent years, several R genes/QTLs that originated from wild/cultivated Solanum species were mapped on the potato genome and a few genes were cloned using molecular approaches. As a result, molecular markers closely linked to resistance genes or QTLs offer a quicker potato breeding option through marker‐assisted selection (MAS). However, limited progress has been achieved so far through MAS in potato breeding. In near future, new resistance genes/QTLs are expected to be discovered from wild Solanum gene pools and linked molecular markers would be available for MAS. This article presents an update on the development of molecular markers linked to late blight resistance genes or QTLs by utilization of Solanum species for MAS in potato.  相似文献   
16.
Pasteurella multocida is a causative agent of many major diseases of which haemorrhagic septiciemia (HS) in cattle & a buffalo is responsible for significant losses to livestock sector in India and south Asia. The disease outcome is affected by various host- and pathogen-specific determinants. Several bacterial species-specific putative virulence factors including the capsular and virulence associated genes have been proposed to play a key role in this interaction. A total of 23 isolates of P. multocida were obtained from 335 cases of various clinically healthy and diseased cattle. These isolates were examined for capsule synthesis genes (capA, B, D, E and F) and eleven virulence associated genes (tbpA, pfhA, toxA, hgbB, hgbA, nanH, nanB, sodA, sodC, oma87 and ptfA) by PCR. A total of 19 P. multocida isolates belonging to capsular type B and 4 of capsular type A were isolated. All isolates of capsular type B harboured the virulence associated genes: tbpA, pfhA, hgbA, sodC and nanH, coding for transferrin binding protein, filamentous hemagglutinin, haemoglobin binding protein, superoxide dismutase and neuraminidases, respectively; while isolates belonging to capsular type A also carried tbpA, pfhA, hgbA and nanH genes. Only 50 % of capsular type A isolates contained sodC gene while 100 % of capsular type B isolates had sodC gene. The gene nanB and toxA were absent in all the 23 isolates. In capsular type A isolates, either sodA or sodC gene was present & these genes did not occur concurrently. The presence of virulence associated gene ptfA revealed a positive association with the disease outcome in cattle and could therefore be an important epidemiological marker gene for characterizing P. multocida isolates.  相似文献   
17.
Assessing the health of the testes in domestic animals is an important aspect of the breeding soundness examination and selection. The aim of the present study was to develop a simple method for scanning and to establish ultrasonographically the gross anatomic structures of the goat testes. Six adult male goats were examined to study the sonographic appearance of normal testes and epididymides using a water bath based ultrasound scanning technique. The ultrasonographic examinations were done using a 5–9 MHz/60 mm (7.5 MHz) linear-array transducer and a B-mode scanner. The ultrasonographic examination was performed in goats after standardizing the procedure on six testes collected from slaughter house. Results showed that in live goats when the probe was placed directly over the scrotum it gave distorted and unclear image. In water bath method the entire scrotum was dipped into a container filled with water and linear probe was used to observe the sonographic features of the testis. Each testis was viewed vertically, resulting in longitudinal image which was frozen, measured and printed through a thermal printer. The results of the ultrasonogram revealed that the testicular parenchyma was homogenous and moderately echogenic throughout. The diameter (mean±se) of the right and left testes was 4.47±0.14 and 4.42±0.07 cm respectively and no significant difference was observed between the testes. The mediastinum testis was a 1.50±0.22 cm wide linear structure of greater echogenicity than the testicular parenchyma when viewed in the transverse plane and nearly circular echogenic “spot” in the midline of the testis when viewed horizontally. The head and tail of the epididymides were easily identified on all the testes, but the epididymal body and ductus deferens were difficult to identify consistently. The tail of the epididymis was easily identified on the distal end of the testis with sonolucent tubules and appeared sonographically as a ‘peaked cap’ upon the testicular parenchyma. The diameter (mean±se) of the tail of right and left epididymis was 2.11±0.18 and 1.92±0.06 cm and no significant difference was observed between epididymides. The vascular pampiniform plexus (1.42±0.18 cm) was easily identified on the proximal end of the testes. The tunics of the testes appeared as a bright echogenic line. Inter-testicular septum appeared between testes as a hyperechoic line. It is concluded that ultrasonography permits a noninvasive evaluation of the internal structure of the scrotum and testes and water bath based sonographic examination may prove to be a valuable simple diagnostic methodology for evaluating physiopathologic conditions of goat testes and can be employed as a routine investigative method during breeding soundness and clinical examination.  相似文献   
18.
Among cereals, only maize has not only a high amount of carotenoids, tocopherols, and oil content but also is rich in starch and protein content compared with other major food crops, such as rice and wheat. The present investigation was made primarily to assess the genetic variability for nutritionally important traits in 87 elite maize inbreds representing major heterotic groups in China. Carotenoid and tocopherol fractions were measured by high-performance liquid chromatography (HPLC), whereas oil, starch, and protein contents were detected by a VECTER22/N near-infrared analyzer. Significant interactions between genotypes and years were observed for all the traits. The pooled mean values of beta-carotene, beta-cryptoxanthin, alpha-carotene, lutein, zeaxanthin, and total carotenoids were 0.449, 0.876, 0.121, 5.803, 3.048, and 10.298 microg g (-1), respectively, whereas the combined mean performance of alpha-tocopherol, gamma-tocopherol, delta-tocopherol, and total tocopherols were 23.98, 32.90, 2.189, and 59.55 microg g (-1), respectively. The average protein, starch, and oil contents were observed to be 12.28, 64.51, and 3.55%, respectively. High level of heritability estimates were observed for all the traits and ranged from 65.6% (protein content) to 92.5% (alpha/gamma-tocopherol ratio). Most of the traits studied in this experiment were either significantly positive correlated or independent. The present finding exhibits substantial opportunities to the breeders for improvement of these traits in maize cultivars and also suggests further exploration of a new source of elite breeding stocks containing a high level of these nutritionally important compounds. Finally, these findings may also help in biofortification of maize.  相似文献   
19.
A feeding trial with Macrobrachium rosenbergii was carried out to test the effectiveness of sunflower cake (SFC) as a replacement for conventional protein sources. Four isonitrogenous (~30% crude protein) and isocaloric (388–402 kcal) diets were formulated. Diet‐1 was a control made with conventional ingredients including fish meal, soya bean meal and mustard oil cake. Diet‐2, Diet‐3 and Diet‐4 were made with 30%, 40% and 50% SFC, respectively, replacing the usual protein sources used in Diet‐1. After 100 days, diets with SFC inclusion showed favourable growth and economic performance trends compared to control diet‐1, but without significant differences (p > .05). Better production (572.89 ± 62.99 kg/ha) was observed with Diet‐4 followed by Diet‐2, Diet‐3 and Diet‐1. Diet‐4 revealed the best feed conversion ratio (2.56 ± 0.24), specific growth rate (1.18 ± 0.05) and protein efficiency ratio (1.14 ± 0.10) among these diets. Whole carcass composition analysis revealed highest crude protein (18.19%) and lipid (4.43%) content in prawns fed Diet‐3 followed by Diet‐4. Highest total income, gross margin and benefit cost ratio (BCR) per hectare from prawns were US$5,759, US$2,623 and 1.84, respectively, found in Diet‐4. This study demonstrates that 30%–50% inclusion of SFC has favourable impacts on productivity and profitability compared with controls, with 50% SFC inclusion as the most cost‐effective diet for prawns without apparent compromise in growth, flesh quality or economics. The performances of the diets suggest that SFC may be a suitable substitute for fishmeal, soya bean meal and mustard oil cake in prawn feed. The effectiveness of higher SFC concentrations should also be investigated.  相似文献   
20.
A study was conducted to demonstrate the comparative efficiency of acid phosphatase generated by plants or fungi towards the hydrolysis of different organic P compounds present in soil. The results revealed that acid phosphatases were most efficient in the hydrolysis of glycerophosphate followed by lecithin and phytin. The P release increased with increase in enzyme concentration. Acid phosphatase generated from fungal sources showed three times greater efficiency in the hydrolysis of phytin, two times greater efficiency in hydrolysis of lecithin than plant phosphatase. Both sources were at par in hydrolyzing glycerophosphate. The results suggest that acid phosphatase generated from plant and fungal sources is different and microbial acid phosphatase to be more efficient than that from plant sources.  相似文献   
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