Pyramiding Ty‐2 and Ty‐3 genes for resistance to monopartite and bipartite tomato leaf curl viruses of India          下载免费PDF全文

H. C. Prasanna  D. P. Sinha  G. K. Rai  R. Krishna  S. P. Kashyap  N. K. Singh  M. Singh  V. G. Malathi 《Plant pathology》2015,64(2):256-264

Breeding resistance to whitefly‐transmitted begomoviruses is an important goal of tomato breeding programmes worldwide. So far, resistance to begomoviruses in tomato has been achieved using wild species, and at least five resistance genes (Ty genes) have been studied. The present study was undertaken to combine Ty‐2 and Ty‐3 and to determine the effect of pyramiding on infection of tomato by three diverse begomovirus species. The diagnostic ability of the markers linked to Ty genes was assessed and marker‐assisted selection was used to develop pyramided tomato lines from the crosses between Ty stocks. Five stable pyramided tomato lines that differ in fruit morphology and yield potential were developed. The horticultural performance of pyramided lines in field trials showed that the yield and horticultural traits are well maintained in the plants. The response of these lines was assessed using agroinoculation and field tests in a disease hotspot. The pyramided lines and Ty‐3‐carrying lines exhibited a high level of resistance to the monopartite and two bipartite begomoviruses tested. The pyramided tomato lines developed in this study could be important genetic resources for sustainable tomato production in areas affected by tomato leaf curl virus disease. The combined results of disease resistance tests also showed that Ty‐3 is critical for achieving broad‐spectrum resistance. The limitations of relying on a single gene and the importance of pyramiding are discussed in the light of available evidence on frequent recombination in begomoviruses.  相似文献   

Morphological and DNA Barcoding Evidence for Invasive Pest Thrips,Thrips parvispinus (Thripidae: Thysanoptera), Newly Recorded From India     

Kaomud Tyagi  Vikas Kumar  Devkant Singha  Rajasree Chakraborty 《Journal of insect science (Online)》2015,15(1)

South East Asia pest thrips species, Thrips parvispinus (Karny), is a serious pest on a number of agricultural and horticultural crops in a number of plant families. Based on an integrated approach of morphology and DNA barcoding, invasion of this serious pest is reported first time from India on papaya plantations. Molecular data have corroborated with the morphological identification. Haplotyping data suggested that the Indonesia may be a probable source of invasion of this pest to India.  相似文献   

Gamma Irradiation of Embryogenic Callus Cultures and In Vitro Selection for Salt Tolerance in Sugarcane (Saccharum officinarum L.)     

Vikas Y Patade  P Suprasanna  V A Bapat 《中国农业科学(英文版)》2008,7(9)

Radiation induced mutagenesis followed by in vitro selection was employed for salt tolerance in popular Indian sugarcane (Saccharum officinarum L.) cv.CoC-671.Embryogenic calli were gamma irradiated and exposed to different levels of NaCl (42.8,85.6,128.3,171.1,213.9,256.7,299.5,or 342.2 mM).The relative growth rate (RGR) decreased progressively with increasing salt stress and was the least with a salt stress of 256.7 mM (0.25±0.009),almost 10 fold lesser than the control.The RGR was significantly lower in 85.6 mM and higher salt stressed calli than the control.The survival percent also decreased,with an increase in NaC1 concentration.In case of 10 and 20 Gy irradiated calli,regeneration was observed up to 85.6 mM NaCl selection,medium,whereas,higher treatments (128.3 mM and beyond) exhibited browning initially.However,in the subsequent subcultures,regeneration was obtained in the case of 10 and 20 Gy irradiated calli on 128.3 and 171.1 mM NaCI selections.Higher dose of gamma irradiation (40 Gy) also showed regeneration,but only with 85.6 mM NaCI selection.The unirradiated calli regenerated the highest number of plantlets followed by 10 and 20 Gy irradiated calli on salt selection.A total of 147 plantlets were selected from different salt levels.The salt selected plants are being tested for their field performance.  相似文献   

Volatile and non-volatile metabolites of actinomycetes and the growth of some litter decomposing fungi     

Bharat Rai  Atul K. Srivastava  D.B. Singh 《Soil biology & biochemistry》1981,13(1):75-76

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A new cytoplasmic-nuclear male sterility system in pearl millet   总被引：1，自引：0，他引：1  

K. N. Rai 《Plant Breeding》1995,114(5):445-447

Among the cytoplasmic-nuclear male sterility (CMS) systems reported in pearl millet, Pennisetum glaucum (L.) R. Br., the A_m= A₄ system produces the highest frequency of male-sterile hybrids. A CMS source identified in a large-seeded gene pool (LSGP) was compared with the A₄ system. Seven diverse restorer lines of the A4 system produced hybrids with 81A4 that were all fertile (pollen-shedding score 4 and 68–89% selfed seedset). In contrast, all the hybrids of these inbreds made with the isonuclear line with the LSGP cytoplasm were sterile (pollen-shedding score 1 and 0–3% selfed seedset). Topcross hybrids of four diverse composites made with 81A4 had 10–35% plants that had good fertility (> 50% selfed seedset). In comparison, no plant of any topcross hybrid with the isonuclear line having LSGP cytoplasm exceeded 20% selfed seedset, and it was rare for a plant to exceed even 10% selfed seedset. These differential fertility restoration patterns of hybrids indicate that the LSGP cytoplasm represents a CMS system that is different from the A4 and, by implication, from all those reported to date. This new CMS system is designated A₅.  相似文献   

Cutaneous water loss and respiration rates of various breeds of sheep at high ambient temperatures     

A. K. Rai  Manohar Singh  T. More 《Tropical animal health and production》1979,11(1):51-56

Summary The sweating and respiratory rates in rams of Rambouillet (R), Chokla (C), Malpura (M), R × C and R × M breed/breed crosses were recorded when housed in sheds or exposed to 20, 25, 30, 35 and 42°C ambient temperatures in a climatic chamber. The sweating (cutaneous moisture) was higher (P<0.05) in Rambouillet and its crosses than the natives, the Malpura sheep producing the least sweat at all temperatures. There was no breed difference in the response of increase in sweating up to 35°C but at 42°C the Chokla showed a considerable increase. Sweating was more pronounced on the shoulder than on the mid-side region. Sweating and respiratory rates increased (P<0.05) with the increase in ambient temperature. The Rambouillet exhibited the highest increase in respiration rate at 25°C and the trend continued up to 42°C. The relationship between fleece characteristics, evaporative heat loss and heat tolerance of sheep is discussed.

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Perdida Cutanea De Agua Y Frecuencia Respiratoria De Varias Razas De Ovejas Sometidas A Temperaturas Ambientales Altas

Resumen Se registraron las frecuencias sudorípara y respiratoria en carneros de las razas Rambouillet (R), Chokla (C), Malpura (M), R × C y R × M, alojados en cobertizos o expuestos a temperaturas ambientales de 20, 25, 30, 35 y 42°C en una cámara climática. El sudor (humedad cutánea) fue mayor (P<0.05) en carneros Rambouillet y sus cruces que en animales nativos, siendo la raza Malpura la que menos sudor produjo bajo todas las temperaturas. No se presentaron diferencias significativas entre las diferentes razas respecto a la humedad cutánea hasta los 35°C, pero a los 42°C la raza Chokla presentó un aumento considerable. El sudor fue más notorio en la espalda que en la región média. Las frecuencias respiratoria y sudorípara aumentaron (P<0.05) directa y paralelamente a la temperatura ambiental. La raza Rambouillet tuvo la frecuencia respiratoria más alta a los 25°C, incrementandose esta paulatinamente hasta los 42°C. Se discute la relación entre las caracteristicas del vellon, la pérdida de calor por evaporación y tolerancia al calor de las ovejas.

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Niveau Des Pertes D'eau Par Transpiration, Et Rhythme Respiratoire De Differentes Races De Moutons Soumis A Des Temperatures Ambiantes Elevees

Résumé Les pertes par transpiration et le rythme respiratoire de béliers de Rambouillet (R), Chokla (C), Malpura (M) et de croisements R × C et R × M ont été relevés lorsque les animaux étaient en bergerie ou exposés à des températures ambiantes, dans une chambre climatique, à 20, 25, 30 et 42°C. Les pertes d'eau par transpiration ont été plus importantes (P<0.05) chez les mérinos de Rambouillet et les métis par rapport aux animaux de race locale, les Malpura manifestant les déperditions d'eau moindre à toutes les températures.Il n'y a pas eu de différences raciales dans la réponse à l'accroissement de la transpiration jusqu'à 35°C mais à 42°C les Chokla ont manifesté une augmentation considérable.La déperdition d'eau par transpiration cutanée a été plus prononcée au niveau des épaules que sur le côté du milieu du corps. La transpiration et le rythme respiratoire ont augmenté (P<0.05) avec l'accroissement de la température ambiante. Les mérinos de Rambouillet ont montré la plus importante augmentation du rythme respiratoire à 25°C, température qui a continué de s'accroître jusqu'à 42°C, limite supérieure de l'expérimentation.Les relations entre l'influence de la température sur les pertes d'eau par évaporation et al tolérance des moutons à la chaleur sont discutées.

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Superovulatory Response and Embryo Recovery after Treatment with Different Gonadotrophin during Induced Luteal Phase inCamelus dromedarius     

Vyas S  Rai AK  Goswami PK  Singh AK  Sahani MS  Khanna ND 《Tropical animal health and production》2004,36(6):557-565

Superovulation, embryo recovery and transfer were attempted in 19 dromedary camels of about 6-10 years of age, and having calved at least once. Superovulation was done using two commercially available porcine FSH preparations, FSH-I (II donors) and FSH-2 (8 donors) during a luteal phase created by inducing ovulation with hCG. The superovulatory response was assessed by ultrasonography. The embryo recovery was attempted non-surgically in sitting position on day 8 and day 7 after first mating in one FSH-1 and one FSH-2 group, respectively. Considerable individual variation in response to the superovulatory stimulus was observed. No significant difference was observed between the two groups in terms of superovulatory response and embryo recovery (p > 0.05). In total 30 embryos were recovered from 17 donors (1.51 embryos/donor). Recipients were synchronized with donors using hCG. Eight embryos were transferred, resulting in two pregnancies and live births.  相似文献   

Association analysis of novel polymorphisms in 2′, 5′‐oligoadenylate synthetase gene with reproductive traits in indigenous and cross‐bred cattle of Indian Origin          下载免费PDF全文

R Alex  KP Ramesha  U Singh  S Kumar  RR Alyethodi  R Deb  S Rai  S Sharma  GS Sengar  A Kumar  B Prakash 《Reproduction in domestic animals》2018,53(2):442-449

2′, 5′‐Oligoadenylate synthetases (OAS) are important components of an interferon‐mediated antiviral pathway. No polymorphisms in exonic regions of bovine OAS1 gene have been identified and associated with reproduction traits. The objective of the study was to detect and evaluate the effects of mutations in exonic region of bovine OAS1 gene with reproduction traits in cattle. DNA samples collected from 250 individual cows of two Indian dairy breeds (Sahiwal and Frieswal) of cattle were used in the study. The genetic variants of the OAS1 gene were identified with polymerase chain reaction–single‐strand conformation polymorphism (PCR‐SSCP) and sequence analysis using seven set of primer pairs. The PCR‐SSCP analysis revealed polymorphism in the fragments comprising of exon 2, exon 5 and first fragment of exon 6 while the fragments of exons 1, 3, 4 and second fragment of exon 6 were monomorphic in Sahiwal and Frieswal cattle. The mutations in the amplified region comprising of exon 2 were found to have significant association with age at first breeding and calving, service period, dry period and pregnancy rate. Significant associations were found between SNPs in the exon 5 and service and dry periods of the animal, whereas the genetic variants in the first fragment of the exon 6 showed significant association with age at first breeding and calving. To our knowledge, this study demonstrated for the first time that the polymorphisms in OAS1 gene were associated with reproductive traits and it can be chosen as a candidate gene for improvement of reproductive performance of cattle.  相似文献   

Dimensional issues in agricultural data warehouse designs     

Sree Nilakanta  Kevin Scheibe  Anil Rai 《Computers and Electronics in Agriculture》2008,60(2):263-278

Recently, the government of India embarked on an ambitious project of designing and deploying the Integrated National Agricultural Resources Information System (INARIS) data warehouse for the agricultural sector. The system's purpose is to support macro level planning. This paper presents some of the challenges faced in designing the data warehouse, specifically dimensional and deployment challenges of the warehouse. We also present some early user evaluations of the warehouse. Governmental data warehouse implementations are rare, especially at the national level. Furthermore, the motivations are significantly different from private sectors. Designing the INARIS agricultural data warehouse posed unique and significant challenges because, traditionally, the collection and dissemination of information are localized.  相似文献   

Carbohydrate metabolism during tuber initiation in potato: A transient surge in invertase activity marks the stolon to tuber transition     

J. S. Minhas  V. K. Rai  H. S. Saini 《Potato Research》2004,47(3-4):113-126

Summary The relationship between carbohydrate metabolism and tuber initiation in potato was determined by monitoring changes in the amount of starch and sugars along with the activities of sugar metabolizing enzymes upon transfer of plants to tuber-inducing conditions (TI; short days, cold nights) from non-inducing conditions (NTI: long days, warm nights). Switch to TI conditions caused an immediate slow-down in plant growth and triggered swelling of stolon tips, which went on to develop into tubers. Leaves of plants moved to TI conditions accumulated less starch and sugar while their stolon tips showed a sudden upsurge in starch content and a sharp decline in sugars even before any tip swelling was detectable. These changes were paralleled by a transient surge in the activity of cell wall invertase (74%) and soluble invertase (30%) in stolon tips of plants transferred to TI conditions in two unrelated cultivars under different experimental conditions. As the surge in invertase activity faded, it was replaced by a substantial increase in sucrose synthase activity as the tuber enlargement proceeded. The transient increase in invertase activity just prior to tuber initiation appears to mark a turning point in the transition of stolon tip to tuber.  相似文献