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排序方式: 共有171条查询结果,搜索用时 93 毫秒
161.
Gülay Mann Simon Diffey Helen Allen Jennifer Pumpa Zena Nath Matthew K. Morell Brian Cullis Alison Smith 《Journal of Cereal Science》2008
Mixing measurements provide valuable information about dough strength and stability (STAB) traits. These measurements are important in milling and baking operations, and for varietal selection in wheat breeding programmes. There are several techniques with different sample sizes used for measuring these traits so there is interest in examining the agreement between methods in terms of genotypic (varietal) rankings. This issue has been investigated by using two different mixing methods, a small-scale Mixograph (2 g) and large-scale Farinograph (50 g) using data from a doubled haploid population (190 lines) from a Chara (excellent dough strength)×WW2449 (poor dough strength) cross. The cross was grown in a field trial at the Wagga Wagga Agricultural Institute (WWAI) in 2000. Eleven mixing traits were measured and compared according to a statistical design. The estimated genetic correlation matrix for six of the 11 mixing traits, dough development time (DDT), STAB, mixing tolerance index (MTI), maximum bandwidth (MBW), bandwidth at peak resistance (BWPR) and peak resistance (PR) revealed that for these dough-strength-related parameters, both methods were measuring equivalent traits, although individual parameters had widely different coefficients of variation. In this population, PR was correlated with the extensibility trait length determined by large-scale extension testing. None of the large-scale or small-scale mixing traits was an effective predictor of the small-scale extensibility parameter extensibility at Rmax (Ext_Rmax). The data verified that small-scale Mixograph tests are a robust and efficient alternative to large-scale Farinograph tests for both commercial breeding and research. 相似文献
162.
Chandra Vir Singh Bidhan Chandra Ghosh Bishwa Nath Mittra Rama Kant Singh 《植物养料与土壤学杂志》2008,171(3):466-470
Nitrogen and weeds are two important factors that influence the productivity of rainfed upland rice (Oryza sativa L.) in tropical Asia. A low recovery of applied fertilizer N in rainfed uplands is generally associated with high nitrate leaching losses and weed interferences. Field experiments were conducted during the wet seasons of 2002 and 2003 at the research farm of Central Rainfed Upland Rice Research Station, Hazaribag, Jharkhand, India, to determine the response of upland rice to nitrogen applied at 60 kg N ha–1 as different forms of urea (single pre‐plant application of controlled‐release urea, single pre‐plant application of urea supergranules, and split application of prilled urea with or without basal N) against no N application under three weed‐control regimes (unweeded, pre‐emergence application of butachlor at 1.5 kg a.i. ha–1 supplemented with one single hand weeding or two hand weedings). The response of rice to applied N varied greatly among the three weed‐control regimes. Across the different N treatments, the application of 60 kg N ha–1 resulted in a grain‐yield increase above the unfertilized control of only 0.24 Mg ha–1 in unweeded treatments, whereas yields increased by 1.07 Mg ha–1 when butachlor application was supplemented with a single hand weeding and by 1.28 Mg ha–1 with two hand weedings. Among the weed‐control measures, hand weeding twice produced highest grain yield in both years. The comparison of different forms of urea showed that a single pre‐plant application of controlled‐release urea resulted in average grain yields of 1.57 and 1.87 Mg ha–1 compared to 1.32 and 1.30 Mg ha–1 in the case of the recommended practice of split‐applied prilled urea in the years 2002 and 2003, respectively. The highest agronomic N use efficiency of 15–20 kg grain per kg N applied and the highest apparent N recovery of 39%–45% were attained with controlled‐release urea, suggesting that this N form is particularly beneficial for upland‐rice cultivation under variable rainfall conditions, provided weeds are controlled. 相似文献
163.
Aboveground biomass and carbon stock in the largest sacred grove of Manipur was estimated for trees with diameter [10 cm at 1.37 m height.The aboveground biomass,carbon stock,tree density and basal area of the sacred grove ranged from 962.94 to 1130.79 Mg ha~(-1),481.47 to 565.40 Mg ha~(-1) C,1240 to 1320 stem ha~(-1) and79.43 to 90.64 m~2 ha~(-1),respectively.Trees in diameter class of 30–40 cm contributed the highest proportion of aboveground biomass(22.50–33.73%).The aboveground biomass and carbon stock in research area were higher than reported for many tropical and temperate forests,suggesting a role of spiritual forest conservation for carbon sink management. 相似文献
164.
Sarma Banashree Buragohain Smrita Dhruba Jyoti Nath 《Archives of Agronomy and Soil Science》2017,63(1):35-47
A 2-year field experiment was conducted in wheat ecosystem to assess the key soil biological characteristics in inceptisols of northeastern region of India. Nine treatments using organic inputs (farmyard manure and vermicompost) and mineral fertilizers were applied by modulating the doses of organics and mineral N fertilizer. Soil enzymes (urease, phosphatase, dehydrogenase, fluorescein diacetate (FDA) and arylsulphatase), microbial biomass carbon (MBC), bacteria and fungi populations were measured before seed sowing (GS1), at flowering stage (GS2) and after harvest (GS3) of wheat, whereas total organic carbon (TOC) was studied at GS3. GS2 recorded significantly higher soil enzyme activities, except FDA, which increased considerably at GS3. Enzyme activities, available N and TOC significantly (p ≤ 0.05) enhanced with application of organic inputs even with reduced (50%) mineral N. Except urease and phosphatase, other enzymes did not respond significantly to mineral fertilization. Vermicompost application increased mean enzyme activities, MBC, microbial growth and TOC fractions (particulate organic carbon, humic acid and fulvic acid carbon) than farmyard manure. Significant (p ≤ 0.05) positive correlations (r = 0.61–0.87) were obtained between TOC and its fractions with studied soil enzymes. Thus, in conclusion, 5 t ha–1 organics incorporation (especially vermicompost) in wheat fertility programme can uphold soil biological health, reduce (50%) N application and would be a sustainable option for wheat grown in inceptisols of northeastern region of India. 相似文献
165.
Archana Das Vigya Kesari Arpita Nath Alika Khare Latha Rangan 《Journal of Crop Science and Biotechnology》2013,16(1):75-81
Antimicrobial activity of crude rhizome oils from some important members of Zingiberaceae from Northeast India was carried out in the present study. The plants used were Curcuma amada, C. longa, Zingiber moran, and Z. zerumbet. Rhizomes of the four species were collected and rhizome oil was extracted using six different polar and non-polar solvents. The antimicrobial property of the crude oil was studied against human pathogens using disc-diffusion and viability assay. The rhizome oil of all the 24 extracts exhibited potent antimicrobial activity against all pathogenic bacterial and fungal strains tested. Hydrodistilled fractions of the four species studied showed better effect among all solvents. Water extract of Z. moran was found to be the highest effective antimicrobial agent of all. Antibacterial effect of the water fractions was also characterized against Gram-positive and Gram-negative bacteria using micro Raman spectroscopy. This investigation shows that the essential oils from the wild and domestic species of the family Zingiberaceae from Northeast India are a potential source of bioactive compounds with tremendous medicinal, economic, and therapeutic value. The wild and endemic species Z. moran represents an interesting and promising source of plant-derived antimicrobial agent in the development of new drugs against pathogens. 相似文献
166.
167.
Rodrigo Chaves Macan Carlos Eduardo Camargo Bruna Lampe Zielinski Nathália Gonçalves Hesketh Cardoso Natália Santana Siqueira de Lara Tácia Gomes Bergstein-Galan Romildo Romualdo Weiss Luiz Ernandes Kozicki 《Reproduction in domestic animals》2021,56(3):459-466
Timed artificial insemination (TAI) has boosted the use of conventional artificial insemination (CAI) by employing hormonal protocols to synchronize oestrus and ovulation. This study aimed to evaluate the efficiency of a hormonal protocol for TAI in mares, based on a combination of progesterone releasing intravaginal device (PRID), prostaglandin (PGF2α) and human chorionic gonadotropin (hCG); and compare financial costs between CAI and TAI. Twenty-one mares were divided into two groups: CAI group (CAIG; n = 6 mares; 17 oestrous cycles) and TAI group (TAIG; n = 15 mares; 15 oestrous cycles). The CAIG was subjected to CAI, involving follicular dynamics and uterine oedema monitoring with ultrasound examinations (US), and administration of hCG (1,600 IU) when the dominant follicle (DF) diameter's ≥35 mm + uterine oedema + cervix opening. The AI was performed with fresh semen (500 × 106 cells), and embryo was recovered on day 8 (D8) after ovulation. In TAI, mares received 1.9 g PRID on D0. On D10, PRID was removed and 6.71 mg dinoprost tromethamine was administered. Ovulation was induced on D14 (1,600 IU of hCG) regardless of the DF diameter's, and AI was performed with fresh semen (500 × 106 cells). On D30 after AI, pregnancy was confirmed by US. The pregnancy rate was 80.0% in TAIG and 82.3% in CAIG (p > .05). The TAI protocol resulted in 65% reduction in professional transport costs, and 40% reduction in material costs. The TAI was as efficient as CAI, provided reduction in costs and handlings, and is recommended in mares. 相似文献
168.
Even though many forest villagers have been living on forest department land and serving the department in the northeastern hill forests region of Bangladesh since the early 1950s, their livelihood has not yet been fully explored. This paper examines the livelihoods of forest villagers (Khasia ethnic people) and their contribution to forest conservation, using data from the Sylhet forest division. The forest villagers are well-endowed with all the elements of a sustainable livelihoods framework, though human capital in terms of education is not satisfactory. Strong social capital, stable natural capital and a productive market-oriented agroforestry system facilitate the generation of financial and physical capital that make the livelihoods of Khasia people sustainable. At the same time, their reciprocal contributions in terms of forest protection and plantation development support forest conservation. However, some institutional issues such as insecure land tenure with regular agreement renewal problems need to be resolved for the sake of their livelihoods and forest conservation. Lessons learned from the study can be utilized in formulating future participatory forest management schemes in the country. 相似文献
169.
Summary Carthamus tinctorius (2n = 2x = 24) (family Asteraceae), commonly known as safflower, is widely cultivated in agricultural production systems of Asia,
Europe, Australia and the Americas as a source of high-quality vegetable and industrial oil. India ranks first in the production
of safflower oil. Fourteen cultivars, widely cultivated in various agro-climatic regions of India, have been fingerprinted
by RAPD, ISSR, and AFLP markers utilizing 36, 21 primers, and 4 primer combinations, respectively. On an individual assay
basis, AFLP has proven to be the best marker system as compared with the other two markers applied as assessed by high discriminating
power (0.98), assay efficiency index (33.2), marker index (18.2), resolving power (40.62), and genotype index (0.856). Thirty-six
RAPD and 21 SSR primers could differentiate a maximum of eight and four cultivars, respectively, whereas, two AFLP primer
combinations could fingerprint all the 14 cultivars. To understand genetic relationships among these cultivars, Jaccard's
similarity coefficient and UPGMA clustering algorithm were applied to the three marker data sets. Mean genetic similarities
ranged from 0.689 (AFLP) to 0.952 (ISSR). Correlation coefficient comparisons between similarity matrices and co-phenetic
matrices obtained with the three markers revealed that AFLP displayed no congruence vis-a-vis RAPD and ISSR data. However,
strong correlation was observed between RAPD and ISSR marker systems. This paper reports the start of molecular biology programme
targeting nuclear genome of safflower, a major world oilseed crop about whose genetics very little is known. 相似文献
170.
Tomato leaf curl disease is a severe threat to tomato production. Yield losses are generally high in the absence of effective management strategies. The disease is caused by tomato leaf curl virus (ToLCV) and is transmitted by a whitefly vector that is challenging to control. Resistance to ToLCV is absent from most cultivated tomato gene pools, although the use of resistant cultivars would provide a better control option than minimizing the vector population. Unfortunately, resistance sources based on field screening break down when virus pressure is severe. Our previous screening and virus testing of 40 tomato genotypes led to the identification of a highly resistant genotype, Solanum pimpinellifolium AAU2019, as a new source of resistance. In this study, we investigated the inheritance and genetics of resistance to ToLCV in the cross of Pusa Ruby × S. pimpinellifolium AAU2019 in F2 and BC1Ps populations, revealing a monogenic recessive gene (best-fit ratios of resistance: susceptible to be 1:3 and 0:1) responsible for ToLCV resistance in S. pimpinellifolium AAU2019. Hence, S. pimpinellifolium AAU2019 could be considered as a potential donor parent in breeding programmes to develop tomato cultivars with resistance to ToLCV. 相似文献