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1.
Solomon Tulu TADESSE Oene OENEMA Christy van BEEK Fikre Lemessa OCHO 《农业科学与工程前沿(英文版)》2021,8(1):159-174
2.
Mobbs D Petrovic P Marchant JL Hassabis D Weiskopf N Seymour B Dolan RJ Frith CD 《Science (New York, N.Y.)》2007,317(5841):1079-1083
Humans, like other animals, alter their behavior depending on whether a threat is close or distant. We investigated spatial imminence of threat by developing an active avoidance paradigm in which volunteers were pursued through a maze by a virtual predator endowed with an ability to chase, capture, and inflict pain. Using functional magnetic resonance imaging, we found that as the virtual predator grew closer, brain activity shifted from the ventromedial prefrontal cortex to the periaqueductal gray. This shift showed maximal expression when a high degree of pain was anticipated. Moreover, imminence-driven periaqueductal gray activity correlated with increased subjective degree of dread and decreased confidence of escape. Our findings cast light on the neural dynamics of threat anticipation and have implications for the neurobiology of human anxiety-related disorders. 相似文献
3.
Fikre Tsion Tesfaye Kassahun Assefa Kebebew 《Journal of Crop Science and Biotechnology》2018,21(4):367-374
Journal of Crop Science and Biotechnology - Knowledge on the extent and pattern of diversity in crop species is a precondition for any crop improvement as it helps breeders in determining apt... 相似文献
4.
Chris Ojiewo Emmanuel Monyo Haile Desmae Ousmane Boukar Clare Mukankusi‐Mugisha Mahendar Thudi Manish K. Pandey Rachit K. Saxena Pooran M. Gaur Sushil K. Chaturvedi Asnake Fikre NPVR Ganga Rao CV SameerKumar Patrick Okori Pasupuleti Janila Jean Claude Rubyogo Chigeza Godfree Essegbemon Akpo Lucky Omoigui Stanley Nkalubo Berhanu Fenta Papias Binagwa Michael Kilango Magdalena Williams Omari Mponda David Okello Mekasha Chichaybelu Amos Miningou Joseph Bationo Dramane Sako Sory Diallo Candidus Echekwu Muhammad Lawan Umar Richard Oteng‐Frimpong Haruna Mohammed Rajeev K. Varshney 《Plant Breeding》2019,138(4):487-499
Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement. 相似文献
5.
Pooran M. Gaur Srinivasan Samineni Mahendar Thudi Shailesh Tripathi Sobhan B. Sajja Veera Jayalakshmi Durdundappa M. Mannur Adiveppa G. Vijayakumar Nadigatla V. P. R. Ganga Rao Chris Ojiewo Asnake Fikre Paul Kimurto Robert O. Kileo Nigusie Girma Sushil K. Chaturvedi Rajeev K. Varshney Girish P. Dixit 《Plant Breeding》2019,138(4):389-400
Chickpea (Cicer arietinum L.) is a dry season food legume largely grown on residual soil moisture after the rainy season. The crop often experiences moisture stress towards end of the crop season (terminal drought). The crop may also face heat stress at the reproductive stage if sowing is delayed. The breeding approaches for improving adaptation to these stresses include the development of varieties with early maturity and enhanced abiotic stress tolerance. Several varieties with improved drought tolerance have been developed by selecting for grain yield under moisture stress conditions. Similarly, selection for pod set in the crop subjected to heat stress during reproductive stage has helped in the development of heat‐tolerant varieties. A genomic region, called QTL‐hotspot, controlling several drought tolerance‐related traits has been introgressed into several popular cultivars using marker‐assisted backcrossing (MABC), and introgression lines giving significantly higher yield than the popular cultivars have been identified. Multiparent advanced generation intercross (MAGIC) approach has been found promising in enhancing genetic recombination and developing lines with enhanced tolerance to terminal drought and heat stresses. 相似文献
6.
Demis Fikre Limeneh Hussien Mohammed Beshir Fekadu Gebretensay Mengistu 《Journal of plant nutrition》2020,43(9):1229-1247
AbstractThe experiment was conducted at Kulumsa, South East Ethiopia, using four levels of nitrogen (N) (0, 50,100 and 150?kg N ha?1) and four levels of phosphorus (P) (0, 35, 70 and 105?kg P2O5 ha?1) fertilizers arranged in 4?×?4 factorial arrangements in randomized complete block design with three replications. The available P was increased after harvest due to the application of N and P fertilizer at the rates of 100 or 150?kg N ha?1 and 70 or 105?kg P2O5 ha?1. More specifically, nutrients concentration and nutrient uptake were significantly (p?<?.01) varied among treatment combinations and nutrient use efficiency was declined by increasing N and P after optimum rates. The higher physiological efficiency of N (53.47?kg kg?1) and P (580.41?kg kg?1) and the highest apparent recovery of N (19.62%) and P (2.47%) was recorded from application of 50?kg N ha?1 and P at 70?kg P2O5 ha?1 and the highest agronomic efficiency of N (10.78?kg kg?1) and P (15.25?kg kg?1) was recorded from N at the rate of 50?kg N ha?1 and P at 35?kg P2O5 ha?1, respectively. The combination of N at 100?kg N ha?1 and P at 70?kg P2O5 ha?1 was promising combination that generated highest net benefit 488,878.5 ETB (Ethiopian birr) ha?1 with the highest marginal rate of return (36638%) and gave the highest seed yield (1858.82?kg ha?1) with yield increment of about 57.72% over the control. 相似文献
7.
Sero-prevalence of bovine brucellosis and its risk factors in Jimma zone of Oromia Region,South-western Ethiopia 总被引:1,自引:1,他引:0
Nuraddis Ibrahim Kelay Belihu Fikre Lobago Merga Bekana 《Tropical animal health and production》2010,42(1):35-40
A cross sectional sero-prevalence study was conducted on 1,595 cattle in Jimma zone, Ethiopia to investigate the status of
bovine brucellosis and identify potential risk factors. Sera samples were analyzed using Rose Bengal Plate Test (RBPT) and
Complement Fixation Test (CFT). The overall individual and herd level sero-prevalences were 3.1% (n = 1,595) and 15.0% (n = 227), respectively. The sero-prevalence of bovine brucellosis at individual animal level was significantly higher in non-pregnant
(11.18%) than pregnant (2.77%) and lactating (22.35%) than non-lactating animals (2.46%). Moreover, significantly higher sero-prevalence
was observed in herds of larger sizes. Individual animal sero-prevalence was also positively associated with the occurrence
of abortion (26.98 and 1.54% in those with and without previous history of abortion, respectively). Generally, the sero-prevalence
of bovine brucellosis found in Jimma area was not high and the sero-prevalence was closely associated with some of the risk
factors considered at individual animal and herd level. 相似文献
8.
Jean‐Claude Rubyogo Essegbemon Akpo Lucky Omoigui Gaur Pooran Sushil Kumar Chaturvedi Asnake Fikre Desmae Haile Ajeigbe Hakeem Emmanuel Monyo Stanley Nkalubo Berhanu Fenta Papias Binagwa Michael Kilango Magdalena Williams Omari Mponda David Okello Mekasha Chichaybelu Amos Miningou Joseph Bationo Dramane Sako Zoumana Kouyate Sory Diallo Richard Oteng‐Frimpong Julius Yirzagla Teryima Iorlamen Umar Garba Haruna Mohammed Chris Ojiewo Alpha Kamara Rajeev Varshney Shyam Narayan Nigam Pasupuleti Janila Hajisaheb Lalasab Nadaf Sylvia Kalemera 《Plant Breeding》2019,138(4):474-486
There are several hurdles to ensure sustainable seed production and consistent flow of improved legume varieties in sub‐Saharan Africa (SSA) and South Asia (SA). The unreliable demand, autogamous nature of most of the grain legumes, and slow variety replacement rate by smallholder farmers do not provide strong incentive for private seed companies to invest in legume seed business. Unless a well thought‐out and comprehensive approach to legume seed delivery is developed, current seed shortages will continue, eroding emerging market opportunities. The experiences reported here are collated through a 10‐year partnership project, the Tropical Legumes in SSA and SA. It fostered innovative public–private partnerships in joint testing of innovative market‐led seed systems, skills and knowledge enhancement, de‐risking private sector initiatives that introduced in new approaches and previously overlooked entities in technology delivery. As new public and private seed companies, individual seed entrepreneurs and farmer organizations emerged, the existing ones enhanced their capacities. This resulted in significant rise in production, availability and accessibility of various seed grades of newly improved and farmer demanded legume varieties in the target countries. 相似文献
9.
Bekele Dagnachew Tesfaye Kassahun Fikre Asnake 《Journal of Crop Science and Biotechnology》2021,24(2):191-201
Journal of Crop Science and Biotechnology - Chickpea (Cicer arietinum L.) is one of the most important food legumes in the world. However, Fusarium wilt is one of the major yield limiting factors... 相似文献
10.
Calf survival and reproductive performance of Holstein–Friesian cows in central Ethiopia 总被引:1,自引:1,他引:0
This study was carried out to evaluate the reproductive performance and calves survival rate of Holstein–Friesian (HF) herd
in Holeta, central highland of Ethiopia. A retrospective analysis of 26 years data was carried out, from which records of
724 age at first calving (AFC), 2,022 calving intervals (CI), 2,971 breeding efficiencies (BE), 260 abortions, 111 stillbirths
were derived from 795 cows. Moreover, 738 female calves’ records were also included for survival rate study. The overall least
squares means of AFC, CI, and BE were 40.9 ± 0.33 months, 475 ± 2.84 days, 81.9 ± 0.26%, respectively, while the incidence
rates of abortion, stillbirth, and female calves survival rate for this herd were 8.0%, 3.4%, and 77.5%, respectively. The
effects of parity number and year of birth/calving on CI and BE were significant (P < 0.001). Moreover, birth year had significant (P < 0.001) effect on AFC and calves survival rate, while calving season had significant effect on BE. The reproductive performance
found in this study was lower than the performance reported in many tropical regions and the genetic potential of HF breed
in their origins. Moreover, higher loss due to calf mortality was observed. Thus, the centre should consider appropriate measures
to improve its herd reproductive performance and calves survival rate for attaining its aspired objectives. 相似文献