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71.
Akhil Ranjan Baruah Noriko Ishigo-Oka Mieko Adachi Yasuyo Oguma Yoshiro Tokizono Kazumitsu Onishi Yoshio Sano 《Euphytica》2009,165(3):459-470
The present study was conducted to understand the pattern of variation and the genetic bases for cold tolerance at the early
growth stage in Asian rice. The genetic variation was investigated at the germination, plumule and seedling stages among 57
strains including cultivated rice (Oryza sativa ssp. indica and ssp. japonica) and its wild progenitor (Oryza rufipogon). The significant differentiation of cold tolerance was observed among the taxonomically divided groups. At the germination
stage, both indica and japonica subspecies tended to be more tolerant than O. rufipogon, whereas at the plumule and seedling stages, ssp. japonica tended to be more tolerant than ssp. indica and O. rufipogon. Furthermore, in cold tolerance at the plumule stage, the clinal variation across the latitude of origins was observed within
O. rufipogon and ssp. japonica, suggesting that the current pattern of variation seems to have been shaped by both their phylogenetic histories and on-going
adaptation to the local environments. QTL analysis between O. sativa ssp. japonica (tolerant) and O. rufipogon (susceptible) revealed five putative QTLs for cold tolerance at the plumule and seedling stages but not at the germination
stage. Substitution mapping was also carried out to precisely locate the two major QTLs for cold tolerance at the plumule
stage, which could be used for improvement of tolerance to cold stress in ssp. indica. 相似文献
72.
Christian Ulrichs Inga Mewis Sujit Adhikary Atanu Bhattacharyya Arunava Goswami 《Journal of pest science》2008,81(2):79-84
Antifeeding and toxic effects of chemical extracts from Porteresia coarctata Takeoka on the insect pest Spodoptera litura (F.) were investigated in the laboratory. Hexane extracts of P. coarctata leaves were re-dissolved in dimethyl sulfoxide and applied in water to leaves of Ricinus communis L. (castor). A concentration of 1,000 and 2,000 ppm extract exhibited significant antifeeding and toxic effects to third
instar larvae when compared to the same concentration of dimethyl sulfoxide in water as control. One day after feeding on
extract-treated castor leaves, the mortality of S. litura larvae was 50%. Mortality increased to 95% after 11 days at a dosage of 2,000 ppm. Compared to the control, third instar
larvae fed on castor leaves treated with P. coarctata leaf extract at different concentrations showed significant reduction in protein and DNA content in the fat body and midgut
tissues. Results demonstrate the insecticidal and antifeedant properties of P. coarctata leaf extract against the generalist pest S. litura leading to biochemical changes in the insect body. Thus, P. coarctata contains phytochemicals, and the extract, in crude and pure form, has potential as a botanical insecticide in alternative
control strategies against Lepidoptera pests. 相似文献
73.
K. K. Gangopadhyay Ashish Singh Manas Kumar Bag Pragya Ranjan T. V. Prasad Anirban Roy M. Dutta 《Genetic Resources and Crop Evolution》2017,64(4):775-790
The wild species in general is considered to be the reservoir of genes especially for biotic and abiotic stresses. In okra, the predominant biotic stresses are yellow vein mosaic disease (YVMD), shoot and fruit borer and leaf hopper. Sixty eight (68) accessions belonging to four wild Abelmoschus species [Abelmoschus caillei (A. Chev.) Stevels, Abelmoschus manihot (L.) Medik., Abelmoschus moschatus (L.) Medik. and Abelmoschus tuberculatus Pal et Singh] and eight okra varieties were characterized and evaluated for phenological characters including biotic stresses under natural epiphytotic condition. The wild species examined consisted of 18 accessions (16 exotic and 2 indigenous) of A. caillei, 29 accessions of A. manihot, 16 accessions of A. moschatus and 5 accessions of A. tuberculatus. All the wild Abelmoschus species exhibited high diversity (as measured by Shannon Diversity Index) for 3 qualitative characters viz. intensity of stem colour, leaf shape, epicalyx shape, 13 quantitative characters and 3 biotic stress parameters. Among the wild species, A. caillei and A. tuberculatus showed maximum and minimum diversity for qualitative characters, respectively. There was significant variation for 19 out of 24 quantitative characters studied. Inter-species diversity pattern as estimated through Ward’s Minimum Variance Dendrogram and Principal Component Analysis revealed clear differentiation among the species with minimum overlapping indicating close association between geographical origins and clustering pattern. Intra-species diversity indicated role of specific adaptation in sub-clustering. Resistance to YVMD was found in accessions belonging to three wild species viz. A. caillei, A. manihot and A. moschatus while resistance to shoot and fruit borer and leaf hopper was found in accessions of all the four wild species. The resistant accessions can further be used for introgressing biotic stress resistance through pre-breeding into cultivated okra species. 相似文献
74.
Two controlled studies were conducted to evaluate the persistent efficacy of moxidectin (10%) long-acting (LA) injectable formulation against Dictyocaulus viviparus, Haemonchus placei, Trichostrongylus axei and Oesophagostomum radiatum in cattle. The moxidectin LA injectable formulation was administered as a single subcutaneous injection into the proximal third of the ear at a dose rate of 0.01 ml/kg BW to provide 1.0 mg moxidectin/kg BW. The product had persistent efficacy of >90% against D. viviparus, H. placei and Oe. radiatum for at least 150 days post-treatment and against T. axei for at least 90 days post-treatment. 相似文献
75.
Ranjan Laik Santosh Kumar Singh Vipin Kumar S. P. Singh Arvind Shukla Nidhi 《Journal of plant nutrition》2019,42(3):296-306
Zinc (Zn) fertilization is important for Zn crop biofortification as well as increasing yields, thus proper Zn recommendations for soil application is needed for Zn deficient soils. The effectiveness of Zn applications was evaluated in different combinations of rates (2.5, 5.0, 7.5, and 10.0?kg?ha?1 per year) and frequencies (initial, alternate, and every year) in rice (Oriza sativa L.) – wheat (Triticum aestivum L.) cropping system in a Zn-deficient upland calcareous soil in the fourth year. Zn applications to rice at 7.5 and 10?kg?ha?1 of alternate year and 5.0 to 10?kg?ha?1 of every year had the highest rice equivalent yield as compared to no-Zn treatment. Hence, Zn application to rice at 7.5?kg?ha?1 at alternate years is the lowest rate at which highest rice equivalent yield of rice-wheat cropping system can be obtained. 相似文献
76.
Amit Ranjan Narottam Prasad Sahu Ashutosh Dharmendra Deo H. Sanath Kumar Sarvendra Kumar Kamal Kant Jain 《Fish physiology and biochemistry》2018,44(4):1037-1049
A 60-day feeding trial was conducted to study the effect of exogenous enzymes (xylanase and phytase) supplementation in the non-fermented and fermented de-oiled rice bran (DORB)-based diet of Labeo rohita. Four test diets (T1-DORB-based diet, T2-fermented DORB-based diet, T3-phytase and xylanase supplemented DORB-based diet, and T4-phytase and xylanase supplemented fermented DORB-based diet) were formulated and fed to the respective groups. Test diets T3 and T4 were supplemented with 0.01% xylanase (16,000 U kg?1) and 0.01% phytase (500 U kg?1) enzymes. One hundred twenty juveniles of L. rohita, with an average weight 5.01?±?0.02 g, were stocked in 12 uniform size plastic rectangular tanks in triplicate with 10 fishes per tank following a completely randomized design (CRD). Exogenous enzyme supplementation to the T3 group significantly improved the growth performance of L. rohita (p?<?0.05). Fermented DORB fed groups registered significantly lower growth irrespective of the supplementation of exogenous enzymes. The carcass composition (except CP %), enzyme activities (except amylase activity), globulin, and A/G ratio did not vary significantly (p?>?0.05). Based on the results of the present study, it is concluded that exogenous enzyme supplementation significantly increases the growth of fish fed with DORB-based diet. 相似文献
77.
Undifferentiated acute calf diarrhoea is a major concern for the dairy industry and its aetiopathogenesis remains diverse.
The present study aimed to examine the role of oxidative stress through estimation of erythrocyte lipid peroxide levels and
blood zinc and copper concentrations using natural cases of diarrhoea in calves aged 15–30 days old. The calves were kept
under identical managemental conditions and were provided with pooled whole colostrum during the first three days and thereafter
with only whole milk until they were 1 month old. Diarrhoeic (n = 11) and normal calves (n = 11) of the same age group (15–30 days old) were randomly selected from an organized dairy farm for the study. The mean
blood zinc concentration (50.01±2.45 μmol/L vs 66.06±3.06 μmol/L) was significantly (p < 0.05) lower and copper concentration was significantly (p < 0.05) higher in diarrhoeic calves (12.90±0.31 μmol/L vs. 9.44±0.16 μmol/L) than in the healthy calves. The erythrocyte
lipid peroxides level was higher (p < 0.05) in diarrhoeic calves (6.88±0.23 nmol malondialdehyde (MDA) per mg of haemoglobin (Hb)) than healthy calves (6.27±0.07
nmol MDA per mg Hb). From the results of the study it is concluded that oxidative stress and antioxidant minerals (zinc and
copper) might play important roles in the aetiopathogenesis of bovine calf diarrhoea. 相似文献
78.
Summary One hundred and four isolates ofPhytophthora infestans were collected during 1990–93 from different potato growing regions of India. They were paired with mating type A1 ofP. capsici to determine their mating type. All isolates from the Indo-Gangetic plains and Assam were the A1 mating type, whereas a mixed
population of A1 and A2 types occurred at Shillong, Darjeeling and Shimla hills. The frequency of A2 isolates was 5–30% in
the Shimla hills and 60% and 58% respectively in the Shillong and Darjeeling hills. 相似文献
79.
Effect of tillage and crop rotations on pore size distribution and soil hydraulic conductivity in sandy clay loam soil of the Indian Himalayas 总被引:2,自引:0,他引:2
Tillage management can affect crop growth by altering the pore size distribution, pore geometry and hydraulic properties of soil. In the present communication, the effect of different tillage management viz., conventional tillage (CT), minimum tillage (MT) and zero-tillage (ZT) and different crop rotations viz. [(soybean–wheat (S–W), soybean–lentil (S–L) and soybean–pea (S–P)] on pore size distribution and soil hydraulic conductivities [saturated hydraulic conductivity (Ksat) and unsaturated hydraulic conductivity {k(h)}] of a sandy clay loam soil was studied after 4 years prior to the experiment. Soil cores were collected after 4 year of the experiment at an interval of 75 mm up to 300 mm soil depth for measuring soil bulk density, soil water retention constant (b), pore size distribution, Ksat and k(h). Nine pressure levels (from 2 to 1500 kPa) were used to calculate pore size distribution and k(h). It was observed that b values at all the studied soil depths were higher under ZT than those observed under CT irrespective of the crop rotations. The values of soil bulk density observed under ZT were higher in 0–75 mm soil depth in all the crop rotations. But, among the crop rotations, soils under S–P and S–L rotations showed relatively lower bulk density values than S–W rotation. Average values of the volume fraction of total porosity with pores <7.5 μm in diameter (effective pores for retaining plant available water) were 0.557, 0.636 and 0.628 m3 m−3 under CT, MT and ZT; and 0.592, 0.610 and 0.626 m3 m−3 under S–W, S–L and S–P, respectively. In contrast, the average values of the volume fraction of total porosity with pores >150 μm in diameter (pores draining freely with gravity) were 0.124, 0.096 and 0.095 m3 m−3 under CT, MT and ZT; and 0.110, 0.104 and 0.101 m3 m−3 under S–W, S–L and S–P, respectively. Saturated hydraulic conductivity values in all the studied soil depths were significantly greater under ZT than those under CT (range from 300 to 344 mm day−1). The observed k(h) values at 0–75 mm soil depth under ZT were significantly higher than those computed under CT at all the suction levels, except at −10, −100 and −400 kPa suction. Among the crop rotations, S–P rotation recorded significantly higher k(h) values than those under S–W and S–L rotations up to −40 kPa suction. The interaction effects of tillage and crop rotations affecting the k(h) values were found significant at all the soil water suctions. Both S–L and S–P rotations resulted in better soil water retention and transmission properties under ZT. 相似文献
80.
The nutritional effect of diet containing decorticated sesame seed extracted with isopropanol (DSS-Iso) was evaluated on growth performance, food efficiency ratio, plasma and tissue lipid profile, plasma protein content, and erythrocyte membrane lipid profile of rats on a comparative basis with diets containing casein (control), soybean meal, and decorticated sesame seed extracted with hexane (DSS-Hex). Rats fed a DSS-Iso-based diet showed body weight gain and food efficiency ratio similar to those of the control groups fed diets prepared with casein, soybean meal, and DSS-Hex. However, dietary proteins exerted a separate effect on plasma lipid concentrations of the rats. Rats fed a DSS-Iso-based diet showed significant decreases in plasma total cholesterol (p < 0.01), triglyceride (p < 0.01), and VLDL+LDL cholesterol (p < 0.01) concentrations in comparison to the rats fed diet containing casein. No significant differences in plasma lipid concentrations were observed for the rats fed diets prepared with soybean meal, DSS-Hex, and DSS-Iso. Rats fed the different dietary proteins did not show much variation in plasma proteins, liver lipids, and erythrocyte membrane lipid concentrations, which suggests that DSS-Iso could be a suitable edible protein like casein or soybean meal. 相似文献