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1.
Diversity among 36 snapmelon landraces, collected from 2 agro-ecological regions of India (9 agro-climatic sub-regions), was assayed using RAPD primers, morphological traits of plant habit and fruit, 2 yield-associated traits, pest and disease resistance and biochemical composition (TSS, ascorbic acid, titrable acidity). Typical differences among accessions were observed in plant and fruit characteristics and snapmelon germplasm with high titrable acidity and possessing resistance to downy mildew, Cucumber mosaic virus, Zucchini yellow mosaic virus, Papaya ringspot virus, Aphis gossypii and Meloidogyne incognita was noticed in the collection. RAPD based grouping analysis revealed that Indian snapmelon was rich in genetic variation and region and sub-region approach should be followed across India for acquisition of additional melon landraces. Accessions of var. agrestis and var. momordica clustered together and there was a separate cluster of the accessions of var. reticulatus. Comparative analysis of the genetic variability among Indian snapmelons and an array of previously characterized reference accessions of melon from Spain, Israel, Korea, Japan, Maldives, Iraq, Pakistan and India using SSRs showed that Indian snapmelon germplasm contained a high degree of unique genetic variability which was needed to be preserved to broaden the genetic base of melon germplasm available with the scientific community. N. P. S. Dhillon and Ranjana contributed equally to this work and are considered the first authors.  相似文献   

2.
We report here the first broad genetic characterization of farmer-developed landraces of melon (Cucumis melo L.) from the Indo-Gangetic plains of India, an area overlooked in previous melon genetic diversity analyses of Indian melon germplasm. Eighty-eight landraces from three melon Groups in two subspecies (C. melo subsp. agrestis Momordica Group, and C. melo subsp. melo Cantalupensis Group and Reticulatus Group) were collected from the four agro-ecological regions (six sub-regions) of two northern states of the Indo-Gangetic plains of India, Uttar Pradesh and Uttarakhand. Significant differences were found among the landraces and eight USA Reticulatus Group reference cultivars for 18 plant and fruit traits: no. of primary branches per plant, days to marketable maturity, sex expression, fruit shape, flesh colour, netting, no. of fruit per plant, fruit weight, shelf life, total soluble solids (°Bx), ascorbic acid (mg/100 g), titratable acidity (%), fruit length and diameter, seed cavity length and diameter, flesh thickness, and resistance to Cucumber mosaic virus. The three melon groups differed significantly for 10 of the plant and fruit traits. Cantalupensis Group and Reticulatus Group accessions were andromonoecious, and the Momordica Group was monoecious. Neighbour-joining (NJ) tree and factorial correspondence analysis (FCA) of simple sequence repeat loci also revealed a high level of genetic variability in this germplasm. The 96 melon genotypes clustered into five groups in the NJ tree analysis: the 16 Indian Reticulatus Group accessions and eight USA reference cultivars formed a distinct group; and the 60 Cantalupensis Group accessions clustered in four other groups with the 12 Momordica Group accessions in a distinct subgroup of one of the Cantalupensis groups. The FCA plot largely confirmed the NJ tree with three distinct groups, one for each melon group. The close affinity of the Indian and USA Reticulatus melons was not unexpected, but it is not clear whether it was inherent in the group and maintained as Reticulatus melons moved from India through Central Asia and Europe to North America, or the result of recent intercrossing of Indian landraces with the USA-derived cultivars and selection for a broad range of Reticulatus type melons.  相似文献   

3.
Emmer wheat (Triticum dicoccon Schrank) is still largely cultivated in India, and highly appreciated for the preparation of traditional dishes. Moreover, its nutritional characteristics could justify a development of its cultivation. The perspective of genetic improvement however requires a good knowledge of the genetic diversity existing within the eco-geographic group of Indian emmer wheats. A set of 48 emmer wheat accessions from India including 28 from a local collection and 20 Indian accessions obtained from CIMMYT, Mexico, was assessed for genetic variability using 47 microsatellite (SSR) markers, distributed over all the 14 chromosomes. The number of alleles per locus ranged from 2 to 9, with an average of 3.87 alleles per locus. A total of 201 alleles were detected at 52 loci with average polymorphic information content of 0.35 per locus and a mean resolving power of 1. The pair-wise similarity coefficients calculated from binary data matrix based on presence or absence of alleles varied from 0.15 to 0.98, but was greater than 0.5 for most accessions, indicating a high level of similarity. A cluster analysis based on the similarity matrix identified nine distinct accessions and three clusters. All the recently developed commercial varieties were distinctly different from the clusters. Based on the analysis, it appears that Indian emmer wheats are not very diverse. Consequently, there is a need to increase the diversity within the Indian emmer wheat eco-geographic group, by introducing diversity from other eco-geographic groups, or even from other wheat species.  相似文献   

4.
Seeds enriched with zinc (Zn) are ususally associated with better germination, more vigorous seedlings and higher yields. However, agronomic benefits of high‐Zn seeds were not studied under diverse agro‐climatic field conditions. This study investigated effects of low‐Zn and high‐Zn seeds (biofortified by foliar Zn fertilization of maternal plants under field conditions) of wheat (Tritcum aestivum L.), rice (Oryza sativa L.), and common bean (Phaseolus vulgaris L.) on seedling density, grain yield and grain Zn concentration in 31 field locations over two years in six countries. Experimental treatments were: (1) low‐Zn seeds and no soil Zn fertilization (control treatment), (2) low‐Zn seeds + soil Zn fertilization, and (3) Zn‐biofortified seeds and no soil Zn fertilization. The wheat experiments were established in China, India, Pakistan, and Zambia, the rice experiments in China, India and Thailand, and the common bean experiment in Brazil. When compared to the control treatment, soil Zn fertilization increased wheat grain yield in all six locations in India, two locations in Pakistan and one location in China. Zinc‐biofortified seeds also increased wheat grain yield in all four locations in Pakistan and four locations in India compared to the control treatment. Across all countries over 2 years, Zn‐biofortified wheat seeds increased plant population by 26.8% and grain yield by 5.37%. In rice, soil Zn fertilization increased paddy yield in all four locations in India and one location in Thailand. Across all countries, paddy yield increase was 8.2% by soil Zn fertilization and 5.3% by Zn‐biofortified seeds when compared to the control treatment. In common bean, soil Zn application as well as Zn‐biofortified seed increased grain yield in one location in Brazil. Effects of soil Zn fertilization and high‐Zn seed on grain Zn density were generally low. This study, at 31 field locations in six countries over two years, revealed that the seeds biofortfied with Zn enhanced crop productivity at many locations with different soil and environmental conditions. As high‐Zn grains are a by‐product of Zn biofortification, use of Zn‐enriched grains as seed in the next cropping season can contribute to enhance crop productivity in a cost‐effective manner.  相似文献   

5.
Andrographis paniculata [(Burm. f.) Wall. ex Nees, family Acanthaceae], commonly known as kalmegh is used both in Ayurvedic and Unani system of medicines for a number of ailments related to digestion, hepatoprotection, hypoglycaemic and as anti-bacterial, analgesic, anti-inflammatory, vermicidal and antipyretic. Although kalmegh is extensively used in Indian Systems of Medicine, but it is not yet cultivated on a large-scale. The supply of herb is met from the wild growing populations which is now under constrain due to over-collection. Considering its value as a drug raw material, genetic variability of A. paniculata was augmented from different geographical regions of India by explorations and was conserved at the National Gene Bank, NBPGR, New Delhi. The therapeutic activity of the herb has been attributed to andrographolide, a bicyclic diterpenoid lactone present in the whole herb. Thirty germplasm collections of A. paniculata were evaluated for bioactive compound andrographolide to find out superior genotype for high drug yield. The andrographolide content in the germplasm was quantitatively analyzed by high performance thin-layer chromatography (HPTLC) at 232 nm. Results indicated wide variability among thirty accessions of A. paniculata for andrographolide content which ranged from 0.72 to 2.99 % on dry weight basis. DIVA-GIS analysis of A. paniculata germplasm for andrographolide content showed that diverse accessions of A. paniculata exist in three Indian states of Orissa, Tamil Nadu and Kerala. Promising accessions having high andrographolide content were identified; IC520361 (2.99 %), IC520395 (2.86 %), IC399125 (2.81 %), IC369404 (2.77 %) and IC520394 (2.61 %). Due to the economic importance of the drug, these promising collections can be exploited for large-scale cultivation for their pharmacologically important constituents mainly andrographolide content and also can serve as potential source for breeding and improvement of cultivars for obtaining higher drug yield.  相似文献   

6.
Taro [Colocasia esculenta (L.) Schott] germplasm accessions collected from different parts of India were subjected to RAPD (Random Amplified Polymorphic DNA) analysis to assess the genetic diversity prevalent and also to test the genetic basis of morphotypic classification. Thirteen random decamer primers out of the 22 tested were used to analyse 32 taro accessions belonging to 28 morphotypes. Three out of these thirteen primers analysed showed 100 per cent polymorphism. Per cent polymorphism varied from 60 to 100 among the polymorphic primers. High genetic diversity was revealed as the similarity coefficient values ranged from 0.50 to 0.98. No two accessions analysed in the present study showed a similarity coefficient value of one thereby indicating their distinctness and presence of high genetic diversity in Indian taro germplasm. Dendrogram obtained from UPGMA analysis grouped 32 accessions in four clusters and three accessions were placed as outliers. Clustering pattern did not show any strict relationship with geographical distribution, morphotype classification and genotypic diversity. Further, accessions classified, as belonging to the same morphotypic group did not always cluster together. Presence of a very close genepool of the wild, weedy and cultivated forms with extreme levels of phenotypic and genotypic variation is suggested as the reason for high genetic diversity reported. Usefulness of DNA markers such as RAPD in characterising and assessing the genetic diversity in Indian taro germplasm is hereby demonstrated.  相似文献   

7.
Guar [Cyamopsis tetragonoloba (L.) Taub.] is an important commercial crop of India, mainly cultivated in the northwestern part and neighboring areas of Pakistan. High morphological diversity is reported in guar. The present study attempts to analyze the genetic diversity in cultivated guar using allozyme polymorphism and compare it with reported morphological diversity. Accessions for the study were selected from a set of guar germplasm conserved at the National Bureau of Plant Genetic Resources, New Delhi. The morphological data of 108 selected accessions was subjected to UPGMA clustering. Fifty-five accessions were then picked randomly from the clusters generated. Tris-borate system (pH 8.3) was found to be most effective for detection of allozyme polymorphism in guar. Ten enzymes were selected for the study out of 18 systems tried, namely, malate dehydrogenase, malic enzyme, phosphogluco isomerase, glutamate oxaloacetate transaminase, esterase, peroxidase, alcohol dehydrogenase, glutamate dehydrogenase, glucose 6-phosphate dehydrogenase and shikimate dehydrogenase. A total of 20 loci were detected with 34 alleles. The number of polymorphic loci in different accessions was observed to be highly variable (0–9). An average of 1.27 allozyme per polymorphic locus was observed. The allele frequency data of the 55 accessions was used to determine genetic diversity parameters. The dendrogram generated on genetic distance showed three clusters in the distance range of 0–0.28. Most of the accessions were in the first clusters in a narrow distance range of 0–0.08. The second cluster consisted of improved varieties and accession from Pakistan. The third cluster of accessions was genetically more distant but there was no definite segregation of accessions according to the place of collection. The accessions from south west Rajasthan were scattered in all the three clusters showing higher variability in this region, also supported by higher morphological variation. The genetic distance was low among accessions of guar, indicating low diversity in India.  相似文献   

8.
Genetic diversity was examined in a collection of 263 Indian bread wheat (Triticum aestivum L.) cultivars using 90 SSR markers. These cultivars were classified into Group I (pre-green revolution cultivars) and Group II cultivars (post-green revolution cultivars). SSR markers were also classified into Set-I SSRs (42 random genomic SSRs) and Set-II SSRs (48 SSRs associated with QTLs for grain weight). The SSRs belonging to Set-II exhibited relatively low level of polymorphism, suggesting that the SSRs associated with QTL for grain weight in wheat were probably under selection pressure during wheat breeding. AMOVA indicated that proportion of the variation within each of the two groups of cultivars accounted for most (87.59%) of the molecular variance, while the variation between the two groups of cultivars accounted for only 12.41% of the variance. The estimates of the average number of alleles/locus and gene diversity due to each of the two sets of SSRs suggested increase in overall genetic diversity after green revolution in Indian bread wheat cultivars. Differences were also observed in genetic diversity among cultivars from each of the six wheat growing agro-climatic zones of India. However, decade-wise analysis of genetic diversity among the post-green revolution cultivars indicated a progressive decline in genetic diversity, thus suggesting a need for involving diverse exotic, synthetic and winter wheat germplasm in Indian wheat breeding programs.  相似文献   

9.
We present here the first comprehensive genetic characterization of melon landraces from the humid tropics of southern India. The genetic diversity among 50 melon landraces collected from 3 agro-ecological regions of southern India (6 agro-ecological sub-regions) was assessed by variation at 17 SSR loci, morphological traits of plant habit and fruit, 2 yield-associated traits, pest and disease resistance, biochemical composition (ascorbic acid, carotenoids, titrable acidity) and mineral content (P, K, Fe, Zn). Differences among accessions were observed in plant and fruit traits. Melon germplasm with high titrable acidity, higher than average amounts of mineral content and resistance to Cucumber mosaic virus, Zucchini yellow mosaic virus, powdery mildew (races 1, 2, 3, 5), Fusarium wilt (races 1, 2), Aphis gossypii and leafminer was recorded in the collection. A high level of genetic variability in melon germplasm was suggested by the SSR analysis. Comparative analysis using SSRs of the genetic variability between Indian melons from north, south, and east regions and reference accessions of melon from Spain, France, Japan, Korea, Iraq, Zambia showed regional differentiation between Indian melon accessions and that Indian germplasm was weakly related to the melon accessions from other parts of the world, suggesting that an important portion of the genetic variability found within this melon collection has not been used yet for the development of new cultivars. Additional collections of acidulus melon germplasm should be made in southern India and adequate management of this important genetic resource is clearly a necessity.  相似文献   

10.
Ziziphus nummularia (Burm. f.) Wight et Arn. is a multipurpose wild economic species well adapted to dry and hot climates of north-western plains, central India and dry regions of peninsular India. This species is reported here for its potential value in drier regions of India and may be considered for future plant genetic resource programmes.  相似文献   

11.
Wheat breeding in Pakistan started in 1930s before partition in the United India and so far has released more than 68 cultivars, but no systematic analyses of the genetic diversity of Pakistan wheat have been made. Twenty Pakistan wheat cultivars released from 1933 to 2002 were examined for genetic diversity and relationships using random amplified polymorphic DNA (RAPD) markers. Forty-two RAPD primers were applied and 184 polymorphic bands were generated for each cultivar. Most of the cultivars were genetically interrelated, although six of them displayed some genetic distinctness. The RAPD variation observed among these cultivars was low. Only 40.7% of the total scorable bands were polymorphic, and 26.1% of the polymorphic bands were observed most frequently (f = 0.95) among the 20 cultivars. The proportions of polymorphic bands for each cultivar ranged from 0.67 in ‘Yecora’ to 0.84 in ‘C-250’ with an average of 0.76. About 1.4% of the RAPD variation might have been fixed over the 69 years of wheat breeding, but such fixation was not statistically significant. These results are significant for future improvement and conservation of Pakistan wheat.  相似文献   

12.
Cardamom (Elettaria cardamomum (L.) Maton) is an important spice crop of India and valued for its dried capsules. Regular surveys are being undertaken by Indian Institute of Spices Research (IISR), Appangala, Karnataka, India for collecting the variable germplasm of cardamom. At present 436 cardamom accessions collected from cardamom growing tracts of South India are conserved in field gene bank. Among the collections, 23 accessions with varied branching pattern were assembled during explorations and characterized for 16 plant, panicle and capsule characters during 2003–2005. The coefficient of variation was greatest for yield per plant (77.94%) followed by branches per panicle (49.40%) and minimum for dry recovery per cent (7.73%). Two accessions, IC 547214 and IC 349544 were identified as promising with desirable yield contributing characters. The accessions, IC 349553 with extensive branching at the proximal end of the panicle and IC 547180 with dark green capsules even after drying were found to be unique. All the characterized accessions are maintained under ex situ cardamom gene bank of IISR.  相似文献   

13.
There is a continuous need to enhance watermelon cultivars for disease and pest resistance. Different U.S. Plant Introductions (PIs) of Citrullus lanatus subsp. lanatus var. lanatus [also known as C. lanatus (Thunb.) Matsum. et Nakai subsp. lanatus var. citroides (Bailey) Mansf. ex Greb.] (CLC) collected in southern Africa are a useful source for enhancing disease or pest resistance in watermelon cultivars. They are also valuable as rootstocks for grafted watermelon, particularly in fields infested with root-knot nematodes or Fusarium wilt. However, there is little information about genetic relationships among these PIs. In this study, genetic diversity was examined among 74 CLC PIs collected from their center of origin in southern Africa. Also, 15 Citrullus lanatus subsp. lanatus (CLL) PIs and the American heirloom cultivars Charleston Gray and Black Diamond (Citrullus lanatus subsp. vulgaris (Schrader ex Eckl. et Zeyh.) Fursa) (CLV) and five Citrullus colocynthis (L.) Schrader (CC) PIs collected in different locations throughout the world were used as out-groups in the phylogenetic analysis for the CLC PIs. Twenty-three high frequency oligonucleotides—targeting active gene (HFO-TAG) primers were used in polymerase chain reaction (PCR) experiments to produce a total of 562 polymorphic markers among the Citrullus PIs and cultivars. Cluster and multidimensional scaling plot analysis produced distinct groups of CLC, CLL, and CC PIs. Several PIs that were designated as CLC or CLL were in transitional positions, indicating that they are the result of gene flow between the major Citrullus groups or subgroups. Population structure analysis indicated that CLC comprises two subgroups; each containing a set of unique alleles. Also, unique alleles exist in the CLL and the CC genotypes. Overall, broad genetic diversity exists among the Citrullus PIs. The data in this study should be useful for identifying PIs with a wide genetic distance between them that could be used in breeding programs aiming to develop heterotic F1 hybrid rootstock lines for grafted watermelon.  相似文献   

14.
Commiphora wightii (Arn.) Bhandari syn. C. mukul Engl. (Burseraceae) is an economically and pharmacologically important slow growing, dioecious, balsamiferous woody, multipurpose shrub heading towards extinction. Commonly known as “Guggul” due to the presence of steroidal compound guggulsterone in the oleo-gum resin, it has been used in treating various ailments and disorders since ancient times (2000 B.C.). Evaluation and confirmation of hypolipidemic effects of guggul based on Ayurvedic text in 1960s provided a new insight into its pharmacological applications. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering activities. Recently, it has been shown to have anti-cancerous activity also. It is found in the dry regions of Indian subcontinent, namely India, Pakistan and Bangladesh. Ruthless and unscientific harvesting of oleo-gum resin from the wild, by local populations, for economic benefits with negligible conservation efforts has made this species endangered and has led to its inclusion in Red Data Book of IUCN. Although this plant has many excellent traits, adequate attention has not been focused on its conservation and improvement. Conventional propagation methods i.e., seeds, cuttings and air layering are in place but have many limitations. Therefore, application of modern biotechnological tools needs to be standardized for harnessing maximum benefits from this pharmaceutically important plant. An efficient regeneration system needs to be in place for improvement of this genus through genetic transformation and production of useful metabolites in cell cultures. Studies are in progress for micropropagation through shoot multiplication and somatic embryogenesis, as well as for secondary metabolite (guggulsterone) production in callus cultures and bioreactors. No selected germplasm is available for C. wightii since it is a wild plant. Breeding programs have not yet been started due to lack of systematic cultivation and conservation programs. Moreover, little information has been gathered regarding the genetic variability in this species using RAPD and ISSR markers. No details are available about genetic makeup and QTL linkage maps. Investigations are in progress to search sex linked markers in this dioecious species. Research is also in progress to decipher the molecular mechanisms underlying various pharmacological actions of guggul. Since the approval of use of guggul as a food supplement by United States Food and Drug Administration in 1994, an exponential increase in research publications on various aspects of research on guggul have been published. Present communication summarizes the problems, progress made and suggests some future directions of research for this important endangered medicinal plant.  相似文献   

15.
Genetic Resources and Crop Evolution - Indian mustard [Brassica juncea (L.) Czern.] is a major edible oil crop of India. The Indian Council of Agricultural Research—National Bureau of Plant...  相似文献   

16.
Little is known about genetic diversity and geographic origin of wheat landraces from Oman, an ancient area of wheat cultivation. The objectives of this study were to investigate the genetic relationships and levels of diversity of six wheat landraces collected in Oman with a set of 30 evenly distributed SSR markers. The total gene diversity, (HT), conserved in the three durum wheat (Triticum durum desf.) landraces (HT = 0.46) was higher than in the three bread wheat (Triticum aestivum L.) landraces (HT = 0.37), which were similar to Turkish and Mexican bread wheat landraces calculated in previous studies. Genetic variation partitioning (GST) showed that variation was mainly distributed within rather than among the durum (GST = 0.30) and bread wheat (GST = 0.19) landraces. Based on modified Rogers’ distance (MRD), the durum and bread wheat landraces were distinct from each other except for a few individuals according to principal coordinate analysis (PCoA). One bread wheat landrace (Greda) was separated into two distinct sub-populations. A joint cluster analysis with other landraces of worldwide origin revealed that Omani bread wheat landraces were different from other landraces. However, two landraces from Pakistan were grouped somewhat closer to Omani landraces indicating a possible, previously unknown relationship. Implications of these results for future wheat landrace collection, evaluation and conservation are discussed.  相似文献   

17.
Twenty-one RAPD and twelve ISSR primers were used for assessment of genetic diversity and establishing phenetic relationships among 35 genotypes of six currently cultivated Indian Momordica species and five genotypes of two Luffa species. A total of 436 RAPD and 230 ISSR scorable fragments were produced of which 99.8% fragments showed polymorphism among the species and varieties of Momordica and Luffa. The level of polymorphism detected by the 33 random primers was higher among the species (99.8%) of Momordica than that estimated among the varieties (61.3%). The varieties belonging to dioecious Momordica species (75.6%) showed a higher level of polymorphism as compared to monoecious species (50.3%). A significant level (68.6%) of polymorphism however was detected by the two marker types among the Indian varieties of monoecious M. charantia species. A wider range of molecular diversity (16–95%) detected by both RAPD and ISSR markers reflected presence of high level of genetic variation among the species and Indian varieties of Momordica and Luffa. The level of inter-specific diversity was maximum (90%) between annual monoecious M. charantia and perennial dioecious M. cochinchinensis whereas the extent of intra-specific diversity was highest particularly in dioecious species (51%) as compared to monoecious species like M. charantia (38%). Wider divergence of the taxon of controversial identity, M. cymbalaria from the other Indian cultivated Momordica species and their evolutionary closeness with Luffa species was evident. The clustering pattern obtained among the 40 genotypes belonging to different Momordica and Luffa species corresponded well with their morphological, cytological and taxonomic classification, which was further supported by high boot-strap values and PCA analysis. Species and genotype-specific fragments detected by the random markers would be useful in introgression breeding for genetic improvement of Momordica cultivated in India. A smaller set of 28 informative random markers screened in this study could precisely differentiate the Momordica genotypes from each other and thus would be of use in many marker-based genotyping applications in Momordica.  相似文献   

18.
Mungbean (Vigna radiata (L.) Wilcz.) is an important leguminous crop cultivated mainly in Asia. Its wild relatives are considered useful genetic resources for mungbean breeding. However, the taxonomic history of mungbean and its wild relatives is complicated and some confusion is still present in recent publications. In this study, we examined the rDNA-ITS sequences and morphological characteristics of 83 gene bank accessions closely related to mungbean. As a result, we classified the 83 accessions into five species and one unclassified accession. The proper taxon name for each species was determined (Vigna grandiflora (Prain) Tateishi et Maxted, Vigna mungo (L.) Hepper, V. radiata, Vigna subramaniana (Babu ex Raizada) Raizada, and Vigna trinervia (Heyne ex Wight et Arn.) Tateishi et Maxted) based on a review of their taxonomic history and morphological comparisons between gene bank accessions and type specimens. A new taxonomic treatment is proposed and a morphological key has been prepared. In this treatment, Vigna radiata (L.) Wilcz. var. setulosa (Dalz.) Ohwi et Ohashi is treated as a synonym of Vigna radiata (L.) Wilcz. var. sublobata (Roxb.) Verdc., and Vigna hainiana Babu, Gopinathan et Sharma is a synonym of V. subramaniana. Accession ‘NI1135’ was revealed to be most closely related to, but is considerably differentiated from, mungbean (V. radiata) based on its rDNA-ITS sequences. It also has distinguishing morphological characters. Plants with similar morphologies and DNA profiles might be distributed in the Indian Himalaya. However, since only one accession is available at present, the taxonomic classification of ‘NI1135’ needs to be reconsidered in the future.  相似文献   

19.
Determination of the saturated hydraulic conductivity (ks) is needed in many studies and applications related to irrigation, drainage, water movement and solute transport in the soil. Although many advances are made for direct measurements of ks, they are usually time consuming and costly. Some attempts have been made to indirectly predict the saturated hydraulic conductivity from the more easily or readily available basic soil properties. The objective of this study was to develop and validate Pedotransfer Functions (PTFs) for estimation of saturated hydraulic conductivity using multiple non-linear regression technique. One hundred and one soil samples were collected from agricultural and forest soils at different depths, at different locations in the Pavanje River basin that lies in the southern coastal region of Karnataka, India. Saturated hydraulic conductivity was measured, by variable falling head method through Permeameter in the laboratory. Prediction accuracies were evaluated using coefficient of determination, root mean square error, mean error, geometric mean error ratio and geometric standard deviation of the error ratio between measured and predicted values. The results show that, the PTFs for the estimation of saturated hydraulic conductivity could be used appropriately for the soils with loamy sand and sandy loam textures falling in this area of the coastal region of southern India.  相似文献   

20.
A field experiment was conducted during the (rabi) seasons of 2009–2010 and 2010–2011 at the research farm, Department of Agronomy, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, to find out the suitable row ratio of Indian mustard (Brassica juncea L.) intercropping with wheat (1:9, 2:9, 1:6, 2:6) and lentil (1:4, 1:5, 2:4, 2:5) row ratios, respectively. The highest yield attributes of mustard were recorded with mustard + lentil (2:5), which was significantly superior to mustard + wheat (1:9) and mustard + lentil (1:5). Maximum seed yield and stover yield of mustard was recorded with mustard + lentil (2:4), which was being significant over other row ratios of mustard + wheat (1:6, 1:9, 2:9) but was at par with mustard + lentil (1:5) and mustard + wheat (2:6) row ratios. Mustard equivalent yield (3128 kg ha?1) recorded under intercropping of mustard with wheat in 1:9 row ratio was significantly higher than sole cropping of mustard, wheat, and lentil, and other remaining intercropping systems. Intercropping of mustard with wheat in 1:9 row ratio showed the highest land equivalent ratio (1.51), aggressivity index (+0.15), net return (60,468 Rs ha?1), and benefit:cost ratio (4.3) among all other intercropping treatments.  相似文献   

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