Wheat growth as influenced by application of agroforestry-tree prunings in Ethiopian highlands     

J. Anthofer  J. Hanson  S. C. Jutzi 《Agroforestry Systems》1998,40(1):1-18

The response of wheat (Triticum aestivum cv. Enkoy) to application of leaf prunings of nine agroforestry-tree species was investigated in a field trial and a six-week pot trial. The tree species were Grevillea robusta, Erythrina abyssinica, Gliricidia sepium, Albizia schimperiana, Acacia nilotica, Acacia polyacantha, Leucaena leucocephala, Leucaena pallida and Entada abyssinica. L. leucocephala, L. pallida, G. sepium and Entada abyssinica proved to be good pruning sources in the pot trial. G. robusta, A. polyacantha, A. nilotica and E. abyssinica had adverse effects on wheat seedlings with increased pruning loads probably due to immobilization processes or allelopathic effects. N and lignin content, C/N ratio, lignin/N ratio, phenolics/N ratio and (phenolics + lignin)/N ratio of the pruning material were all significantly correlated with shoot dry matter production of the wheat seedlings. With the exception of Entada abyssinica, which performed well under field conditions, a similar ranking as in the pot trial was established in the field experiment, but at harvest differences were not as pronounced as in the pot trial. Gliricidia treated wheat produced by far the highest grain yield with 248 g/m².This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

The Role of Legumes in Plant Community Succession of Degraded Grasslands in Northern China     

Guozheng Hu  Hongyan Liu  Yi. Yin  Zhaoliang Song 《Land Degradation \u0026amp; Development》2016,27(2):366-372

Legume species were more and more commonly introduced to degraded grassland for human‐aided restoration. This study aimed to test whether the natural spread of legume contributes to reversal of grassland degradation through making an extensive grassland vegetation and soil survey in Inner Mongolia of China. The results showed that legume biomass increased along a gradient of soil coarsening that was also a gradient of grassland degradation. The total biomass rather than legume biomass was limited by mean annual precipitation at plot level. The presence of legumes increased species richness in degraded steppe vegetation. Constancy of intermediate and climax species of vegetation succession at sites with legumes was higher than that at sites without legumes, implying that legumes might contribute positively to the reversal of grassland degradation. Our study suggests that naturally distributed legumes could benefit the reversal of grassland degradation through promoting plant community succession rather than total plant biomass. Planting legumes would be an effective measure to accelerate the recovery process of degraded grassland with coarsened soil in regions similar to our study region. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

四种豆科牧草花药及组织培养研究的总结   总被引：1，自引：0，他引：1  

郭景文 《青海草业》1998,(2)

利用生物技术方法,对红豆草、苜蓿、百脉根和鹰嘴紫云英进行花药培养及茎尖、茎段的组织培养,诱导愈伤组织、分化成苗且移栽成功。同时对无根苗直接移栽土壤中刺激生根,得到了满意的结果。通过多个品种和30多种培养基的试验,筛选出最适的各类培养基。为利用生物技术进行牧草育种和快速繁殖提供了科学依据。  相似文献   

甘肃省豆科牧草资源及植物区系分析   总被引：2，自引：0，他引：2  

陈本建 《草业科学》2008,25(4):42-45

甘肃省豆科牧草资源有26属、126种,以多年生和草本植物为主.有近80%的种类具有饲用价值,其中30%具有优良的饲用等级,有18%的种类具有毒性.区系中以少型属居多,无中国和甘肃特有属种;共有9个分布区类型和4个变型.在属级水平上以北温带成分为主,温带成分次之,类型间的差异性不显著.热带成分占有较大比例.有东亚、中亚和地中海成分渗入.  相似文献   

Nitrogen concentration in the upper leaves of the canopy is a reliable indicator of plant N nutrition in both pure and mixed grassland swards     

Gaëtan Louarn  Abad Chabbi  François Gastal 《Grass and Forage Science》2020,75(1):127-133

Effective indicators of plant nitrogen (N) nutrition are needed to improve N management in grasslands. This is particularly the case for mixtures that rely on N fixation by legumes as a major N input, because no reference tool such as the nitrogen nutrition index (NNI) exists under these conditions. The aims of this study were to test the reliability of a plant-based index, the N concentration of upper leaves in the canopy (Nup), as a possible alternative for NNI in both pure and mixed grasslands. Data were gathered from four experiments covering a range of pure and mixed grasslands under different N fertilization levels. A cross-validation of Nup predictions against NNI in pure stands, and against two NNI-derived indices in mixtures, was performed. The Nup values appeared to be linearly related to NNI in pure stands of both grasses and legumes. The relationship was identical for the two groups of species and explained up to 86% of NNI variability. In mixtures, Nup also displayed a linear relationship with the two other tested indices, explaining 65% and 78% of variability. The conclusions of the three indices diverged with respect to strongly unbalanced mixtures, where the assumptions regarding the computation of NNI-derived indices were not met. Excluding these situations, the overall relationship between Nup and NNI proved to be identical for mixtures and pure stands. The results suggest that Nup is a valid criterion for plant N nutrition which applies to a broad range of grassland species and to mixture conditions.  相似文献   

Maize–legume intercropping promote N uptake through changing the root spatial distribution,legume nodulation capacity,and soil N availability          下载免费PDF全文

ZHENG Ben-chuan  ZHOU Ying  CHEN Ping  ZHANG Xiao-na  DU Qing  YANG Huan  WANG Xiao-chun  YANG Feng  XIAO Te  LI Long  YANG Wen-yu  YONG Tai-wen 《农业科学学报》2022,21(6):1755-1771

Legume cultivars affect N uptake, component crop growth, and soil physical and chemical characteristics in maize–legume intercropping systems. However, how belowground interactions mediate root growth, N fixation, and nodulation of different legumes to affect N uptake is still unclear. Hence, a two-year experiment was conducted with five planting patterns, i.e., maize–soybean strip intercropping (IMS), maize–peanut strip intercropping (IMP), and corresponding monocultures (monoculture maize (MM), monoculture soybean (MS), and monoculture peanut (MP)), and two N application rates, i.e., no N fertilizer (N–) and conventional N fertilizer (N+), to examine relationships between N uptake and root distribution of crops, legume nodulation and soil N availability. Results showed that the averaged N uptake per unit area of intercrops was significantly lower than the corresponding monocultures. Compared with the monoculture system, the N uptake of the intercropping systems increased by 31.7–45.4% in IMS and by 7.4–12.2% in IMP, respectively. The N uptake per plant of intercropped maize and soybean significantly increased by 61.6 and 31.8%, and that of intercropped peanuts significantly decreased by 46.6% compared with the corresponding monocultures. Maize and soybean showed asymmetrical distribution of roots in strip intercropping systems. The root length density (RLD) and root surface area density (RSAD) of intercropped maize and soybean were significantly greater than that of the corresponding monocultures. The roots of intercropped peanuts were confined, which resulted in decreased RLD and RSAD compared with the monoculture. The nodule number and nodule fresh weight of soybean were significantly greater in IMS than in MS, and those of peanut were significantly lower in IMP than in MP. The soil protease, urease, and nitrate reductase activities of maize and soybean were significantly greater in IMS and IMP than in the corresponding monoculture, while the enzyme activities of peanut were significantly lower in IMP than in MP. The soil available N of maize and soybean was significantly greater increased in IMS and IMP than in the corresponding monocultures, while that of IMP was significantly lower than in MP. In summary, the IMS system was more beneficial to N uptake than the IMP system. The intercropping of maize and legumes can promote the N uptake of maize, thus reducing the need for N application and improving agricultural sustainability.  相似文献   

Genomics,genetics and breeding of tropical legumes for better livelihoods of smallholder farmers     

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   

Effects of long-term legume cover crop incorporation on soil organic carbon, microbial biomass, nutrient build-up and grain yields of sorghum/sunflower under rain-fed conditions     

B. Venkateswarlu    Ch.  Srinivasarao  G. Ramesh    S. Venkateswarlu  & J. C. Katyal 《Soil Use and Management》2007,23(1):100-107

Low organic matter, poor fertility and erosion are common features of rain‐fed Alfisols in southern India. Build‐up of organic matter is crucial to maintain sustainable production on these soils. The possibility of on‐farm generation of legume biomass [horsegram; Macrotyloma uniflorum (Lam.) Verdc.] by using off‐season rainfall was examined in two field experiments involving sorghum and sunflower from 1994 to 2003. The effects of this incorporation were assessed on crop yields and soil properties for 10 years together with fertilizer application. Horsegram biomass ranging from 3.03–4.28 t ha^?1 year^?1 (fresh weight) was produced and incorporated in situ under different levels of fertilizer application. Annual incorporation improved the soil properties and fertility status of the soil, which resulted in improved yields of test crops. With biomass incorporation, mean organic carbon content improved by 24% over fallow. Microbial biomass carbon improved by 28% at site I. Long‐term biomass incorporation and fertilizer application resulted in the build‐up of soil nutrients compared with the fallow plots. Application of N and P alone resulted in a negative balance of soil K. A time‐scale analysis of yields showed that incorporation together with fertilizer application maintained a stable yield trend over a 10‐year period in sorghum, whereas fertilizer application alone showed a declining trend. At the end of 10 years of incorporation, the increase in grain yield because of incorporation was 28 and 18%, respectively, in sorghum and sunflower over fallow when no fertilizers were applied to rainy season crops. The incorporation effect was even larger in plots receiving fertilizer. The growing and incorporation of a post‐rainy season legume crop is a low‐cost simple practice that even small and marginal farmers can adopt in semi‐arid regions of the country. Widespread adoption of this practice, at least in alternate years, can restore the productivity of degraded soils and improve crop yields.  相似文献   

A Review on Options for Management of Cowpea Pests: Experiences From Uganda     

E. Adipala  P. Nampala  J. Karungi  P. Isubikalu 《Integrated Pest Management Reviews》2000,5(3):185-196

More than 100 field pests of cowpea (Vigna unguiculata L. Walp.) can be found in most of the crop production agroecologies in Africa, but four of these – aphids (Aphis craccivora Koch), flower thrips (Megalurothrips sjostedti Trybom), the legume pod borer (Maruca vitrata Fab. Syn. Maruca testulalis Geyer) and pod sucking bugs – are commonly encountered and are of economic importance in Uganda. The diverse cowpea pest complex dictates that a single control strategy is unlikely to produce satisfactory control.Earlier field studies done in eastern and northern parts of Uganda demonstrated that close spacing (30 × 20cm) effectively reduces aphid infestation (early season pest) but seems to promote thrips, legume pod borers and pod bugs infestation. The other option for management of early season pests and nematodes is seed dressing, especially with carbofuran (Furadan 5G). Late season pests are more effectively controlled by the use of foliar sprays, the type of pesticide depending on the pest profile. Intercropping also offers remedial control, but the crop combination must consider the pest profile, cowpea/sorghum intercrop being effective against aphids and thrips, and cowpea/greengram against legume pod borers and pod sucking bugs. Selected combinations of agronomic, chemical and cultural control measures (Integrated Pest Management), especially when combined with early planting, offer better management options than the use of sole treatments. The success of these packages is highly dependent on the degree and level of farmer involvement and to what extent they are tailored to meet his/her production goals.  相似文献   

豆科绿肥草粉对生长育肥猪生产性能和消化道形态的影响     

程园  封朝壁  张文  陈长飞  刘世洪  罗国茂  张国强 《甘肃农业大学学报》2000,35(2):226-226

在能量和蛋白质近似的饲粮条件下,配入0～30％的豆科绿肥草粉,观察其对生长育肥猪生产性能、洞体性状和消化道形态的影响,结果表明：在肥育前期加5％～10％,后期10％～30％的草粉饲粮,并不影响日增重（P＞0.05）;在能量、蛋白质近似条件下草粉水平对胭体性状影响不明显（P＞0.05）。但对板油指数和肠系膜脂肪的沉积影响显著（P＜0.05）;随着饲粮草粉比例增加试猪消化道变长和鲜重增加（P＜0.05）。  相似文献