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91.
Agro-morphological characterization of ovary culture-derived plants of rice (Oryza sativa L.) 总被引:2,自引:0,他引:2
Plants derived from unpollinated ovary culture of ten rice genotypes showed significant variability in agro-morphological
characteristics. The ovary-derived plant (H1) populations were completely haploid, doubled haploid or haploid-doubled haploid
mixture. Haploids had very drastic reduction in plant height, panicle length, grain length, breadth and number and spikelet
fertility (0.0%–2.1%). Doubled haploids from the hybrid of UPRI 95–121 × UPRI 95–165 were normal with fertility ranging between
69.6% and 97.7%. A genetic segregation in ratio of 1:1 was observed for five pigmentation characters in the H1 population
derived from hybrid UPRI 95–122 × UPRI 95–165. Plant height showed the largest coefficient of variability (28.5%) followed
by the number of spikelets per panicle (24.2%), number of grains per panicle (22.0%), percent seed set (9.2%) and panicle
length (9.0%). The range of variation in the H1 population from fully fertile hybrid PMS 2A (CMS) × IR 31802 (restorer) was
similar to its corresponding F2 population for plant height, spikelet fertility and number of grains/panicle. A single clone
of plants from the cultivar BG 1321 exhibited complete male sterility but normal female fertility when pollinated with other
varieties. Ovary-derived plants from the CMS lines PMS 2A and IR 58025A showed stable male sterility and those from thermosensitive
genetic male sterile line UPRI 95–140 showed thermosensitive genetic male sterility. These lines have potential in the hybrid
breeding program and are being currently exploited.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
92.
基于USLE模型利用地理信息系统(GIS)和遥感(RS)对Wadsa-Chincholi流域年土壤流失量空间分布进行调查。空间输入数据由Arc GIS 9.3和RS(ERDAS IMAGINE 9.3图像处理软件)提供,利用USLE对网格内年均输沙量的空间分布进行预测。USLE参数基本单元的网格单元尺寸(GCS)分别为50 m×50 m、100 m×100 m和200 m×200 m。根据流域出口对年均输沙量进行估算。此外,将利用通用土壤流失方程(USLE)估算的产沙量与观测值进行对比。利用USLE模型预测得到50 m×50 m、100 m×100 m和200 m×200 m的年均输沙量分别为在63.80、18.83和3.67 t(hm2·年)。200 m×200 m GCS预测值与观测得到的产沙量基本相符。因此,在200 m×200 m GCS情况下,利用USLE模型得到的预测结果能够用于对Wadsa-Chincholi流域产沙量空间分布的研究。从水土保持角度来看,研究区域涵盖了侵蚀非常严重、侵蚀严重、侵蚀非常高、高度侵蚀和中度侵蚀类,这都需要引起重视。 相似文献
93.
Abstract. A study was carried out to compare the impact of 6-year-old plantations of Prosopis juliflora (Swartz) D.C., Dalbergia sissoo Roxb. Ex. D.C. and Eucalyptus tereticornis Sm. on the physical and chemical properties of sodic soil in the Indo-Gangetic alluvial plains of Uttar Pradesh, India. Soil properties under the three tree species showed significant improvement through a reduction in the pH, electrical conductivity, exchangeable sodium percentage, CaCO3 and gypsum requirement, and by increase in organic C, total N, and available P and K. The six years of reclamation had achieved a marked reduction in exchangeable sodium (from 11.5 to 4.5 cmolc kg−1 ) to a depth of 1.5 m in the soil profile, whereas the levels of exchangeable calcium, magnesium and potassium had increased. There was also a significant reduction in soil bulk density (from 1.66 to 1.24 g cm−3 ) and increases in porosity, water holding capacity, field capacity, permeability and infiltration rate. The equilibrium infiltration rate after 455 min increased from 0.03 cm h−1 in the control to 0.13 cm h−1 under P juliflora and D. sissoo and 0.10 cm h−1 under E. tereticornis . It is concluded that salt-tolerant tree species have a significant impact on soil properties, which could help to rehabilitate the sodic wastelands in the region. 相似文献
94.
Kaniska Mallick Bimal K. Bhattacharya V.U.M. Rao D. Raji Reddy Saon Banerjee H. Venkatesh Vyas Pandey Gouranga Kar Joydeep Mukherjee Sarweshwar P. Vyas Alaka S. Gadgil N.K. Patel 《Agricultural and Forest Meteorology》2009,149(10):1646-1665
A simplified evaporative fraction (Λ) based single-source energy balance scheme was tested with moderate resolution (1 km) noontime satellite observations to evaluate clear sky latent heat flux (λE) estimates over diverse agricultural landscapes. This approach uses two-dimensional (2D) scatter between land surface temperature (LST) and albedo to determine Λ. The operational utility of this scheme was demonstrated for estimating regional evapotranspiration and consumptive water use during rabi (November to April) crop growing season to predict pre-harvest wheat yield (error within 15.9% of reported mean) using time series data. The existence of triangular relations between Λ and LAI (leaf area index) or NDVI (normalized difference vegetation index) was found with basal line (hypotenuse) linearly coupled with LAI or NDVI at low level of surface soil wetness. The analysis of diurnal course of in situ Λ proved the validity of constant-Λ hypothesis over pure, uniform, homogeneous crop canopies but showed irregular and wave-like patterns over heterogeneous, mixed crop canopies. The root mean square error (RMSE) of noontime and daytime average λE estimates with respect to in situ λE measurements were also smaller over homogeneous agricultural canopies (41 and 23 W m−2) with correlation coefficients (r) 0.94 and 0.96, respectively, from 135 clear sky datasets as compared to RMSE over heterogeneous ones (59 and 28 W m−2 with r = 0.66 and 0.82, respectively from 22 datasets). The intercomparison with another Λ based approach (LST–NDVI 2D scatter) showed the supremacy of Λ determined from LST–albedo 2D scatter. The efficiency of LST–NDVI scatter was better during the dry down or water limited phases of crop growth only. The uncertainties of λE estimates were attributed to errors in core radiation budget inputs, relative loss of conservativeness of Λ due to canopy heterogeneity, and the inherent limitations of the single-source approach. There is further scope to reduce present λE uncertainties by combining the new findings on Λ (LST–albedo scatter)–NDVI triangular relations, diurnal Λ and two-source radiation budget. 相似文献
95.
Malik YS Chandrashekar KM Sharma K Haq AA Vaid N Chakravarti S Batra M Singh R Pandey AB 《Tropical animal health and production》2011,43(8):1475-1478
The present study describes detection of picobirnavirus (PBV) in faecal samples from bovine and buffalo calves employing the
polyacrylamide gel electrophoresis (PAGE). A total of 136 faecal samples from buffalo (n = 122) and cow calves (n = 14) exhibiting clinical signs of diarrhoea and from healthy calves were collected during 2007–2010 from subtropical (central
India) and tarai area of western temperate Himalayan foothills (Uttarakhand). The dsRNA nature of the virus was confirmed
by nuclease treatment (RNase A, RNaseT1 and DNase 1). PAGE results confirmed 3.67% (5/136) positivity for PBV, showing a typical
genomic migration pattern with two discrete bands with size of approximately 2.4 and 1.7 kbps for the larger and smaller segments,
respectively. Among the five PBV samples identified, three were from buffalo calves and one from cow calf exhibiting clinical
signs of acute diarrhoea, while one sample from non-diarrhoeic buffalo calf also showed the presence of PBV. None of the samples
showed dual infection of rotavirus and PBV. The preliminary findings indicate sporadic incidences of PBV in bovine calves
and emphasize the need for the development of better diagnostics for early detection and genetic characterization of these
emerging isolates of farm animals of economic significance. 相似文献
96.
Anand Kumar Pandey Gurcharan Singh Dhaliwal Sarvpreet Singh Ghuman Jagir Singh Ajeet Kumar Sudhir Kumar Agarwal 《Tropical animal health and production》2012,45(1):293-298
The current study was aimed to establish the impact of progesterone supplementation (norgestomet progestagen) between days 4 to 10 post-ovulation on subsequent luteal profile and conception rate in buffaloes. The 28 Murrah buffaloes of second to fourth parity, having normal reproductive organs, were estrus synchronized by double PGF2α protocol at 11 days apart. The buffaloes were inseminated during mid- to late estrus and thereafter repeated at 24 h interval. The buffaloes were randomly assigned into two groups: (1) control (no treatment, n?=?14) and (2) treatment group (CRESTAR ear implant, n?=?14). The CRESTAR ear implant (3 mg, norgestomet progestagen) was inserted subcutaneous between days 4 to 10 post-ovulation. The ovaries were scanned at estrus and thereafter on days 4, 10, 16, 21, and 40 post-ovulation to examine the preovulatory follicle (POF) and corpus luteum (CL) diameter. Each ultasonography was followed by blood sample collection for analysis of plasma progesterone concentrations following ovulation. The conception rate was similar (p?>?0.05) between treated and control buffaloes. The pregnant buffalo of the control group had larger (p?<?0.05) POF diameter than nonpregnant counterparts. The CL diameter was similar (p?>?0.05) in both treated and untreated control as well as in their pregnant and nonpregnant buffaloes of the respective groups. The plasma progesterone concentrations were higher (p?<?0.05) in the treatment group on the day 10 post-ovulation as compared to the control buffaloes. It is concluded that norgestomet supplementation had no impact on conception rate and CL diameter but enhances the plasma progesterone concentrations following treatment in buffaloes. 相似文献
97.
Arun Prasad Sanjay Kumar Ankit Pandey Sukhmal Chand 《Biology and Fertility of Soils》2012,48(1):117-122
Rose-scented geranium (Pelargonium sp.) is a highly valued aromatic crop. Its growth is limited by soil salinity and sodicity stress. Arbuscular mycorrhizal
(AM) fungus, phosphate-solubilizing bacteria (PSB), and P fertilizers may enhance the growth and secondary metabolism in geranium
plants. In this context, a pot experiment was conducted to study the effects of PSB, AM fungi (Glomus intraradices), and P fertilizer on the yield, chemical composition of essential oil, and mineral element acquisition of geranium. The
dry matter yield of shoot and essential oil yield, and mineral element (P, K, Ca, Mg, Na, Fe, Cu, and Zn) uptake in shoot
tissues of geranium were significantly increased by the inoculation with AM fungi, co-inoculation with AM fungi and PSB, and
P fertilization as compared to control. While the co-inoculation of geranium with AM fungi and PSB significantly enhanced
the content of the monoterpenes such as citronellol, geraniol, geranial, and a sesquiterpene (10-epi-γ eudesmol), the P fertilization only enhanced the content of a sesquiterpene, 10-epi-γ eudesmol in the volatile oil. We conclude that the co-inoculation of PSB and AM fungi could be the best natural alternative
to phosphate fertilizers to enhance the yield and quality of essential oil from geranium plants grown in sodic soils. 相似文献
98.
Leonardo F.C. Brito DVM PhD Patricia L. Sertich MS VMD Keith Durkin BSc Bhanu P. Chowdhary BVScAH PhD Regina M. Turner VMD PhD Lauren M. Greene VMD Sue McDonnell PhD 《Journal of Equine Veterinary Science》2008,28(7):431-436
A 19-month-old Standardbred colt was donated to the University of Pennsylvania School of Veterinary Medicine with a suspicion of intersexuality. The anal−genital distance and penis were normal, and there was no evidence of intersexuality, but the colt was bilaterally cryptorchid. Several aspects of the colt's behavior appeared unusual, including general temperament and behavior described as sympathetically dull and affable. With herd mates, the colt appeared slow to perceive or to learn the usual intraspecies social cues. An atypical gait characterized by intermittent unnatural shuffle of the hind limbs, sliding them along in short rhythmic strides for 3 to 10 seconds at a time was noted at times when a horse might normally transition from a slow walk to a fast walk or a slow trot. Occasionally the colt exhibited slight protrusion of the tongue through the teeth and lips with jaw movements and smacking of the tongue against the teeth as if struggling to retract the tongue to the normal position. Evaluation of the karyotype combined with fluorescent in situ hybridization (FISH) revealed an abnormal male karyotype showing trisomy of chromosome 27 (65, XY + 27). The colt was euthanized at 24 months of age, and a necropsy revealed no significant abnormalities. This case of trisomy was not associated with developmental abnormalities described in other rare reports of trisomy in horses; however, some features were strikingly similar to that of humans with trisomy 21. FISH was demonstrated to be an excellent method for correct identification of equine chromosomes. 相似文献
99.
Soils are the third biggest sink of carbon on the earth. Hence, suitable land uses for a climatic condition are expected to sequester optimum atmospheric carbon in soils. But, information on how climatic conditions and land uses influence carbon accumulation in the soils on the Himalayan Mountains is not known. This study reports the impact of four climatic conditions (sub-tropical, altitude: 500–1200 m; temperate 1200–2000 m; lower alpine 2000–3000 m; upper alpine, 3000–3500 m) and four land uses (forest, grassland, horticulture, agriculture) on the concentrations and stocks of soil organic carbon (SOC) in upper (0–30 cm) and deeper (30–100 cm) soil depths on the western Himalayan Mountains of India. The study also explored the drivers which influenced the SOC stock build up on the mountains. Rainfall and soil moisture showed quadratic relations, whereas temperature declined linearly with the altitude. SOC stock as well as concentration was the highest (101.8 Mg ha− 1 in 0–30 cm, 227.97 Mg ha− 1 in 0–100 cm) in temperate and the lowest in sub-tropical climate (37 Mg ha− 1 in 0–30 cm, 107.04 Mg ha− 1 in 0–100 cm). Pattern of SOC stock build up across the altitude was: temperate > lower alpine > upper alpine > sub-tropical. SOC stocks in all land uses across the climatic conditions, except agriculture in lower alpine, was higher (0.7 to 41.6%) in the deeper than upper soil depth. SOC stocks in both the depths showed quadratic relations with soil temperature and soil moisture. Other factors like fine soil particles, land-use factor and altitude influenced positively whereas slope and pH, negatively to the SOC stocks. In all climatic conditions, other than temperate, SOC stocks were greater in natural ecosystems like forests and pastures (112.5 to 247.5 Mg ha− 1) than agriculture (63 to 120.4 Mg ha− 1). In temperate climate, SOC stock in agriculture (253.6 Mg ha− 1) on well formed terraces was a little higher than forest (231.3 Mg ha− 1) on natural slope. These observations, suggest that land uses on temperate climate may be treated as potential sinks for sequestration of the atmospheric carbon. However, agriculture in subtropical climate need to be pursued with due SOC protection measures like the temperate climate for greater sequestration of the atmospheric carbon. 相似文献
100.
The methanol extract of stem barks of Alianthus excelsa was partitioned with chloroform. The chloroform extract showed fungistatic and fungicidal activity against Aspergillus niger, A. fumigatus, Penicillium frequentence, P. notatum and Botrytis cinerea. 相似文献