Near-infrared spectroscopy applications for high-throughput phenotyping for cassava and yam: a review

Open Access Article; Published online: 12 Aug 2020The review aimed to identify the different high‐throughput phenotyping (HTP) techniques that used for quality evaluation in cassava and yam breeding programmes, and this has provided insights towards the development of metrics and their application in cassava and yam improvements. A systematic review of the published research articles involved the use of NIRS in analysing the quality traits of cassava and yam was carried out, and Scopus, Science Direct, Web of Sciences and Google Scholar were searched. The results of the review established that NIRS could be used in understanding the chemical constituents (carbohydrate, protein, vitamins, minerals, carotenoids, moisture, starch, etc.) for high‐throughput phenotyping. This study provides preliminary evidence of the application of NIRS as an efficient and affordable procedure for HTP. However, the feasibility of using mid‐infrared spectroscopy (MIRS) and hyperspectral imaging (HSI) in combination with the NIRS could be further studied for quality traits phenotyping

Role of root exudates and root turnover in the below-ground N transfer from Canavalia ensiformis (jackbean) to the associated Musa acuminata (banana)

Jackbean is an annual legume frequently used as green manure in tropical intercropping systems with bananas. Although the beneficial effect of nitrogen (N) release from above-ground residues on banana nutrition is well known, little information is available on the N transfer from jackbean roots before and after the above-ground harvest. The aim of this study was to assess the relative contribution of exudates and root turnover in the N transfer from jackbean to banana in a greenhouse experiment. Nitrogen transfer was studied in a 6-month trial using the 15N leaf feeding method, and estimated with a box model of 15N dilution based on the observed data of 15N content in exudates and decomposing roots. For the sowing–harvest period, the amount of N transferred from jackbean exudates represented 16% of banana N uptake and 0.7% of jackbean N uptake. Therefore, the N transfer flux via exudates was 23 times higher in terms of N input for the recipient plant than in terms of N output for the donor plant. This value, which is an index of the effectiveness of N transfer, was lower than those reported previously for other soil–plant systems in greenhouse conditions. This would be due to differences in root traits of the recipient plants. The amount of transferred N from root turnover after jackbean harvest represented 52% of banana N uptake in that period. The box model described N transfer from both legume N sources adequately (r2 = 0.92). For the whole experiment, 38% of banana N uptake was derived from jackbean (6% from exudates and 32% from root turnover), and 62% from soil N. The results indicated that N transfer from root exudates of jackbean would be a useful but minor process compared with N release from root turnover in soil. The experimental and theoretical approach proposed in this study may be useful in screening studies to assess the capability of herbaceous legumes to transfer N

BIOLOGICAL NITROGEN FIXATION AFTER STEM CUTTING IN TUBEROUS PACHYRHIZUS EROSUS

Yam bean (Pachyrhizus erosus) a tuber-forming legume, is particularly suitable for evaluating the potential availability of the plant reserve carbohydrates for nitrogen fixation (Vaillant et al., 1990,1993). The tuber of this species contains soluble sugars and starch which account, respectively, for 32 and 15% of dry weight. Furthermore, tuberous and non-tuberous plants may be avai lable in inductive or noninductive environment (Robin et al., 1990; Sorcnsen et al., 1993). A stem cutting experiment was conducted with tuberous Pachyrhizus erosus in order to evaluate its potential for maintaining N fixation after aphotosynthate stress. This paper report the effects of such a treatment on the Acetylene Reduction Assay (ARA) of nodules and on the concentration of N fixation products in underground organs

Dynamics of nonstructural carbohydrates and biomass yield in a fodder legume tree at different harvest intensities

International audienc

Dynamics of nonstructural carbohydrates and biomass yield in a fodder legume tree at different harvest intensities

International audienc

Les Biostimulants : Qu’en savons-nous ? Quelles alternatives pour l’agriculture Guyanaise ?

L’agriculture doit relever le défi de nourrir une population grandissante avec des aliments sains, tout en assurant la protection et la préservation des ressources environnementales telles que l’eau, les sols et la biodiversité animale et végétale. Pour faire face à ce défi, l’agriculteur doit s’approprier de nouvelles connaissances, méthodes et outils pour produire des aliments en quantité et en qualité, tout en réduisant les apports chimiques de fertilisants et de produits phytosanitaires néfastes pour les ressources naturelles et la santé humaine. Concevoir des systèmes de culture permettant la transition de l’agrochimie à l’agroécologie est la voie à développer pour réussir ce challenge. Les biostimulants, les biopesticides et les biofertilisants, issus de produits et de processus naturels, constituent une alternative très prometteuse pour les producteurs, qui doivent renouer avec des pratiques et techniques agroécologiques traditionnelles innovantes. Cependant la méconnaissance sur les constituants moléculaires et modes d’actions (principes actifs) de ces produits, engagent scientifiques et agriculteurs dans un partenariat renforcé pour répondre, de manière adéquate, à la demande croissante de moyens permettant de lutter efficacement contre les stress biotiques et/ou abiotiques rencontrés sur les exploitations agricoles. Notre objectif est de décrire brièvement l’état des connaissances sur les biostimulants et biofertilisants, en présentant leurs enjeux pour l’agriculture guyanaise, définition, intérêt agronomique, mode de préparation et d’application, les risques éco-toxicologiques ainsi que le cadre réglementaire où ils se positionnent. Des études de cas concrètes et l’évaluation de leurs propriétés offrent aux utilisateurs potentiels des bases et repères pour leur fabrication et leur utilisation en production végétale. L’analyse de leur pertinence agronomique et de leurs conditions d’appropriations par les agriculteurs en Guyane dans des systèmes agro-écologiques, de même que leur potentiel de développement, seront abordés dans la conclusion et les perspectives.Agriculture faces the challenge of producing healthy food to feed an increasingly growing population, while ensuring the protection and preservation of environmental resources such as water, soil and animal and plant biodiversity. To meet this challenge, the farmer must acquire new knowledge, methods and tools to produce food in quantity and quality while reducing the use of chemicals and fertilizers inputs and phytosanitary products that are very detrimental to natural resources and human health. Driving crop systems in an agro-ecological way is the way to develop this challenge. Biostimulants and biofertilizers, derived from natural products and processes, are a very promising alternative for producers, who may review traditional innovative agro-ecological practices and technicals. However, ignorance of the molecular components and mode of action (active principle) of those products, engage scientists and farmers in a reinforced partnership to respond adequately to the increasing demand for means to effectively combat biotic and / or abiotic stresses encountered on farms. Our objective in this article is to present an inventory of knowledge on biostimulants and biofertilizers, presenting their challenges for Guyanese agriculture, definition, function, method of preparation and application, ecotoxicological risks and regulatory framework in which they position themselves. Concrete case studies and evaluation of their properties offer potential users, basics and benchmarks for their manufacture and use in crop production. The analysis of their agronomic relevance and their conditions of appropriation by farmers in French Guiana in agro-ecological systems, as well as their potential for development will be addressed in the conclusion and prospects