Background Pigeonpea Cajanus cajan (L.) Millspaugh, one of the most important food legumes of semi-arid tropical and subtropical regions, has limited genomic resources, particularly expressed ...sequence based (genic) markers. We report a comprehensive set of validated genic simple sequence repeat (SSR) markers using deep transcriptome sequencing, and its application in genetic diversity analysis and mapping. Results In this study, 43,324 transcriptome shotgun assembly unigene contigs were assembled from 1.696 million 454 GS-FLX sequence reads of separate pooled cDNA libraries prepared from leaf, root, stem and immature seed of two pigeonpea varieties, Asha and UPAS 120. A total of 3,771 genic-SSR loci, excluding homopolymeric and compound repeats, were identified; of which 2,877 PCR primer pairs were designed for marker development. Dinucleotide was the most common repeat motif with a frequency of 60.41%, followed by tri- (34.52%), hexa- (2.62%), tetra- (1.67%) and pentanucleotide (0.76%) repeat motifs. Primers were synthesized and tested for 772 of these loci with repeat lengths of ≥18 bp. Of these, 550 markers were validated for consistent amplification in eight diverse pigeonpea varieties; 71 were found to be polymorphic on agarose gel electrophoresis. Genetic diversity analysis was done on 22 pigeonpea varieties and eight wild species using 20 highly polymorphic genic-SSR markers. The number of alleles at these loci ranged from 4-10 and the polymorphism information content values ranged from 0.46 to 0.72. Neighbor-joining dendrogram showed distinct separation of the different groups of pigeonpea cultivars and wild species. Deep transcriptome sequencing of the two parental lines helped in silico identification of polymorphic genic-SSR loci to facilitate the rapid development of an intra-species reference genetic map, a subset of which was validated for expected allelic segregation in the reference mapping population. Conclusion We developed 550 validated genic-SSR markers in pigeonpea using deep transcriptome sequencing. From these, 20 highly polymorphic markers were used to evaluate the genetic relationship among species of the genus Cajanus. A comprehensive set of genic-SSR markers was developed as an important genomic resource for diversity analysis and genetic mapping in pigeonpea.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Pigeonpea (Cajanus cajan), an important food legume crop in the semi-arid regions of the world and the second most important pulse crop in India, has an average crop productivity of 780 kg/ha. The ...relatively low crop yields may be attributed to non-availability of improved cultivars, poor crop husbandry and exposure to a number of biotic and abiotic stresses in pigeonpea growing regions. Narrow genetic diversity in cultivated germplasm has further hampered the effective utilization of conventional breeding as well as development and utilization of genomic tools, resulting in pigeonpea being often referred to as an ‘orphan crop legume'. To enable genomics-assisted breeding in this crop, the pigeonpea genomics initiative (PGI) was initiated in late 2006 with funding from Indian Council of Agricultural Research under the umbrella of Indo-US agricultural knowledge initiative, which was further expanded with financial support from the US National Science Foundation's Plant Genome Research Program and the Generation Challenge Program. As a result of the PGI, the last 3 years have witnessed significant progress in development of both genetic as well as genomic resources in this crop through effective collaborations and coordination of genomics activities across several institutes and countries. For instance, 25 mapping populations segregating for a number of biotic and abiotic stresses have been developed or are under development. An 11X-genome coverage bacterial artificial chromosome (BAC) library comprising of 69,120 clones have been developed of which 50,000 clones were end sequenced to generate 87,590 BAC-end sequences (BESs). About 10,000 expressed sequence tags (ESTs) from Sanger sequencing and ca. 2 million short ESTs by 454/FLX sequencing have been generated. A variety of molecular markers have been developed from BESs, microsatellite or simple sequence repeat (SSR)-enriched libraries and mining of ESTs and genomic amplicon sequencing. Of about 21,000 SSRs identified, 6,698 SSRs are under analysis along with 670 orthologous genes using a GoldenGate SNP (single nucleotide polymorphism) genotyping platform, with large scale SNP discovery using Solexa, a next generation sequencing technology, is in progress. Similarly a diversity array technology array comprising of ca. 15,000 features has been developed. In addition, >600 unique nucleotide binding site (NBS) domain containing members of the NBS-leucine rich repeat disease resistance homologs were cloned in pigeonpea; 960 BACs containing these sequences were identified by filter hybridization, BES physical maps developed using high information content fingerprinting. To enrich the genomic resources further, sequenced soybean genome is being analyzed to establish the anchor points between pigeonpea and soybean genomes. In addition, Solexa sequencing is being used to explore the feasibility of generating whole genome sequence. In summary, the collaborative efforts of several research groups under the umbrella of PGI are making significant progress in improving molecular tools in pigeonpea and should significantly benefit pigeonpea genetics and breeding. As these efforts come to fruition, and expanded (depending on funding), pigeonpea would move from an ‘orphan legume crop' to one where genomics-assisted breeding approaches for a sustainable crop improvement are routine.
•Soil carbon stability and nitrogen dynamics in long-term experiment was analyzed.•Application of FYM in addition to NPK produced greater size of resistant C pool.•Additional carbon input in NPK plot ...had no effect on resistant carbon pool.•Carbon stability significantly affected the N dynamics in soil.•N availability in soil is linearly related with acid-hydrolyzable C pool.
Improved understanding of the process of carbon (C) stabilization is critical to managing emissions from agricultural soils and optimizing crop yield. We assessed soil organic C (SOC) stability and nitrogen (N) dynamics in a long-term fertilization experiment (started in 1972) conducted at three different locations in India (Jabalpur-Vertisol, Palampur-Alfisol and Ranchi-Alfisol). We measured soil organic C (SOC), C pools and stocks in the treatments of no fertilization as control, inorganic fertilization as NPK and integrated fertilization as NPK+farm yard manure (FYM). Quantification of different SOC pools was done by a procedure of acid hydrolysis followed by a long-term (247 days) incubation study. Based on crop yield and C storage, NPK+FYM was the best treatment for improving crop productivity and SOC sequestration. Integrated fertilization for 38 years increased SOC across sites. In the NPK treatment, additional C input (3–9 times higher) in the form of root biomass did not significantly change C pools. Application of FYM in addition to NPK enhanced the acid non-hydrolysable fraction of SOC across sites. Stability of SOC significantly influenced N dynamics in soil and the availability of N in soil is correlated with the amount of C in the acid-hydrolysable pool (R2=0.64, p=0.01) but not with SOC (R2=0.12, p=0.01). Long-term use of chemical fertilizers did not significantly affect soil total N content.
A field experiment was conducted at the Research Farm of the ICAR-Indian Institute of Soil Science, Bhopal (India) to study influence of different integrated nutrient management (INM) modules on soil ...potassium (K) fractions. The experiment comprised with twelve treatments laid out in randomized block design (RBD) with three replications under maize-chickpea cropping sequence. The treatments included general recommended dose (GRD), soil test crop response (STCR) dose; combinations of inorganic and organic inputs and only organic modules. The soil samples were collected at crop harvest and analyzed for various K fractions viz., water soluble-K, available-K, exchangeable-K, HNO.sub.3 -K, lattice-K and total-K. The results indicated that potassium fractions were significantly (p = 0.05) affected by different treatments. Different INM modules significantly enhanced significantly K availability in soil. Among various INM modules studied, treatment 11 (application of 20 t ha.sup.-1 FYM in maize with 5 t ha.sup.-1 FYM every year in chickpea) proved most beneficial for improving the soil K fractions. Findings of this type are important for K fertilizer management during crop production in areas with low soil fertility.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Yield decline or stagnation and its relationship with soil organic matter fractions in soybean (
Glycine max L.)–wheat (
Triticum aestivum L.) cropping system under long-term fertilizer use are not ...well understood. To understand this phenomenon, soil organic matter fractions and soil aggregate size distribution were studied in an Alfisol (Typic Haplustalf) at a long-term experiment at Birsa Agricultural University, Ranchi, India. For 30 years, the following fertilizer treatments were compared with undisturbed fallow plots (without crop and fertilizer management): unfertilized (control), 100% recommended rate of N, NP, NPK, NPK+ farmyard manure (FYM) and NPK
+
lime. Yield declined with time for soybean in control (30
kg
ha
−1
yr
−1) and NP (21
kg
ha
−1
yr
−1) treatments and for wheat in control (46
kg
ha
−1
yr
−1) and N (25
kg
ha
−1
yr
−1) treatments. However, yield increased with time for NPK
+
FYM and NPK
+
lime treatments in wheat. At a depth of 0–15
cm, small macroaggregates (0.25–2
mm) dominated soil (43–61%) followed by microaggregates (0.053–0.25
mm) with 13–28%. Soil microbial biomass carbon (SMBC), nitrogen (SMBN) and acid hydrolysable carbohydrates (HCH) were greater in NPK
+
FYM and NPK
+
lime as compared to other treatments. With three decades of cultivation, C and N mineralization were greater in microaggregates than in small macroaggregates and relatively resistant mineral associated organic matter (silt
+
clay fraction). Particulate organic carbon (POC) and nitrogen (PON) decreased significantly in control, N and NP application over fallow. Results suggest that continuous use of NPK
+
FYM or NPK
+
lime would sustain yield in a soybean–wheat system without deteriorating soil quality.
In present study the multigrain mixes prepared from finger millet malt, moth bean malt and drumstick leaf powder stored in packaging material i.e., polythene pouch and aluminium laminated pouches. ...The stored multigrain mixes were observed during each day from 0, 15, 30, 45, 60, 75 and 90 days. Nutritional analysis indicated that both multigrain mixes packed packaging material and during storage period moisture content increases from 7.0 to 8.745%, protein content decreases from 14.97 to 12.85%, fat decreases 2.15 to 1.23%, fiber content decreases from 0.95 to 0.31%, ash content decreases from 2.24 to 1.67% carbohydrate increases from 70.13 to 72.159 %, whiteness index decreases from 24.19 to 21.187. Storage in plastic pouch is less than 90 days, based on the growth of yeast and mold.
The study was conducted to analysis of physico-chemical properties of drumstick leaf powder. Drumstick leaf were dried in a convective hot air dryer at 30oC, 40oC and 50oC. The air velocity inside ...the dryer was 2-3 m/s, the drying process takes 6 hrs, 27hrs, and 19 hrs time to dry the product at 30⁰C, 40⁰C, and 50⁰C.
The experimental drying data of drumstick were applied to six Moisture ratio models, namely, the Newton model, modified Page model, Henderson and Pabis, Logarithmic, Two term and Exponential Model was found to be the best for explaining the drying characteristics of drumstick leaf. The effective moisture diffusivity varied from 3.651 ×10-11, 4.503×10-11 and to 7.343×10-11 over the temperature range studied, with activation energy of 28.281 kJ/mol for drying of drumstick leaf. The drumstick leaf powder contains moisture 10.85 to 15.56 %, protein 22.88 to 23.979 %, fat 1.80 to 2.42 %, fibre 11.53 to 12.16 %, ash 3.69 to 4.93 %, carbohydrate 40.94 to 849.25% The flour had average water absorption capacity (3.081to 4.22l g/cc), bulk density (3.081 to 0.445 g/cc) were recorded.
Intensive cropping with conventional tillage results in a decline of soil organic carbon (SOC) with consequent deterioration of soil physical properties. Some studies indicate that this decline in ...SOC can be arrested by way of organic manure application and improved nutrient management practices. This study was conducted to find out the long-term effects of inorganic fertilizer, manure and lime application on organic carbon content and physical properties of an acidic Alfisol (Typic Haplustalf) under an annual soybean–wheat crop rotation. Six treatments namely, control (CON), nitrogen fertilization (NIT), nitrogen and phosphorus (NP), nitrogen, phosphorus and potassium (NPK), NPK plus manure (NPKM) and NPK plus lime (NPKL) from a long-term fertilizer experiment continuing at Ranchi, India, were chosen for this study. Soil samples were collected from the selected treatments after 29 crop cycles and analyzed for physical and chemical properties. The results indicated that SOC content in all the treatments decreased from initial levels, but the decrease was considerably less in NPKM (8.7%) and NPKL (10.9%) treatments than that in NIT (28.3%) treatment. The SOC at 0–15 and 15–30 cm depth was lowest in NIT and CON. The NPKM, NPKL and NPK treatments up to 30 cm soil depth recorded significantly higher SOC than NIT and CON. Application of balanced fertilizer along with manure (NPKM) or lime (NPKL) improved soil aggregation, soil water retention, microporosity and available water capacity and reduced bulk density of the soil in 0–30 cm depth over CON. In contrast, soil aggregate stability, microporosity and available water capacity were significantly lower in the NIT plots than that in CON. The study thus suggests that soil management practices in acidic Alfisols should include integrated use of mineral fertilizer and organic manure or lime to maintain the organic carbon status and physical environment of soil.
Core test is commonly required in the area of concrete industry to evaluate the In-situ compressive strength of concrete and sometimes it becomes the unique tool for safety assessment of existing ...structure. Core test is therefore introduced in most of the codes. The current method of core testing involves the use of compression tests on cylindrical specimens obtained from cores drilled in-situ. The cores are damaged during extraction, transportation, more time and money involved during sawing and capping and sometimes cores are misplaced and also there is misinterpretation of strength due to variation in site and laboratory conditions. In order to overcome the difficulties, a new machine which simplifies the entire tedious testing process has been developed and used in this research work for testing of concrete strength within the structure. The principle of the machine is to test the un-extracted core with lesser diameters within the site for its Compressive strength. To test the reliability of the machine, cores of different diameters and L/D ratios were tested both by conventional method and newly developed machine and Comparative statistical analysis such as Student's t-test analysis is done to check the homogeneity of data and the general similarity between the results of Conventional method and the newly developed machine. Nearly 54 core samples of 24mm, 36 samples of 42mm and 36 samples of 67mm diameter of L/D ratios 1.0, 1.5, 2.0 were tested. The statistical analysis like Student's t-test proved that there is no considerable difference in the newly developed method and the conventional method of concrete core testing.
In south Asian countries, production fatigue has been observed as yields which have started declining or stagnating under long-term experiments in multiple cropping systems due to continuous ...cultivation. We examined the potential impact of continuous cultivation of crops in rotation, and fertilizer and manure application on yield trends, soil organic carbon (SOC) storage, soil quality parameters (active fractions of SOC in particular) and sustainable yield index (SYI). Crop rotations included in the study were: rice–wheat–jute, soybean–wheat and sorghum–wheat system at Barrackpore (Typic Eutrochrept), Ranchi (Typic Haplustalf) and Akola (Typic Haplustert), respectively. Field treatments included unfertilized (control), 100% N, 100% NP, 100% NPK and 100% NPK
+
FYM. The negative yield trend was observed in unbalanced use of inorganic N and NP application at all the three sites. The positive yield trend was observed in the NPK and NPK
+
FYM treatments at Ranchi and Akola. However, significantly negative-yield trends were observed in these treatments at Barrackpore under rice-based system. Results showed that the SOC in the unfertilized plot (control) decreased by 41.5, 24.5, and 15.5% compared to initial values in Barrackpore, Ranchi and Akola, respectively, wherein the treatment receiving NPK and NPK
+
FYM either maintained or improved it over initial SOC content in these sites. The estimated annual C input values in NPK
+
FYM treatments were 4392, 4159 and 3113
kg
ha
−1
year
−1 in rice–wheat–jute, sorghum–wheat and soybean–wheat system, respectively. Active fractions of SOC, viz., water-soluble carbon and hydrolysable carbohydrates, soil microbial biomass C and N, dehydrogenase and alkaline phosphatase activity, improved significantly with the application of NPK and NPK
+
FYM. The content of SOC significantly (
p
≤
0.05) correlated with SYI and active fractions of SOC, which support better sustainable productivity. Results suggest that current fertilizer recommendations of 100% recommended NPK are adequate for maintaining SOC and its active fractions as well. The causes of yield decline are mostly location specific but depletion of SOC and its active fractions seems to be a general cause.
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