Transmission and pathogenicity of papaya virus E: insights from an experimental papaya orchard

A study was conducted to investigate epidemiological aspects of papaya virus E (PpVE), a cytorhabdovirus commonly found in papaya (Carica papaya L.) plantings of Ecuador. Besides papaya, PpVE was found in three Fabaceae weeds, including Rhynchosia minima, Centrosema plumieri and Macroptilium lathyroides; the latter being the species with the highest virus prevalence. Greenhouse experiments showed that in M. lathyroides, single infections of PpVE induce only mild leaf mosaic, whereas in mixed infections with cowpea severe mosaic virus, PpVE contributes to severe mosaic. In papaya, PpVE did not induce noticeable symptoms in single or mixed infections with papaya ringspot virus. Transmission experiments confirmed that whiteflies (Bemisia tabaci) transmit PpVE in a semi-persistent, non-propagative manner.

Efeitos do estresse hídrico na germinação de sementes e desenvolvimento inicial de plântulas Macroptilium lathyroides

A adaptabilidade ecológica de plantas daninhas em áreas agricultáveis está contribuindo para a seleção de biótipos mais resistentes. Assim, o conhecimento dos fatores que controlam a germinação das sementes pode gerar subsídios para estratégias de manejo dessas espécies, alternativas ao uso exclusivo de herbicidas. O presente trabalho teve como objetivo avaliar a germinação e o desenvolvimento inicial das plântulas de figo de pombo (Macroptilium lathyroides) sob diferentes disponibilidades hídricas no substrato. As sementes foram mantidas em caixas gerbox sobre papéis umedecidos com soluções de PEG 6000 e manitol, nos potenciais hídricos de 0,0; -0,2; -0,4; -0,6; -0,8; e -1,0 MPa. Foram realizadas avaliações diárias de germinação, IVG e, no final de dez dias, determinou-se o comprimento da parte aérea, comprimento radicular e massa seca de plântula. Os resultados demonstraram que esta espécie é osmoticamente afetada tanto por PEG 6000 como por manitol, sendo que potenciais abaixo de -0,2 MPa de PEG 6000 são considerados críticos à germinação. O manitol provocou redução gradativa no índice de velocidade de germinação e desenvolvimento das plântulas.

PRESELECCIÓN DE GERMOPLASMA DE MACROPTILIUM LATHYROIDES (L.) URB. CON TOLERANCIA AL SOMBREADO

El estudio de la respuesta al sombreado en especies forrajeras nativas es una estrategia de premejoramiento útil para la selección de los materiales adaptados a los sistemas productivos silvopastoriles, predominantes en la ganadería de cría bovina de Argentina. En el presente estudio se evaluaron caracteres agronómicos y ecofisiológicos en entradas de Macroptilium lathyroides del banco de germoplasma “Ing. Agr. José M. Alonso” de la UNL, en condiciones naturales y artificiales de luz y sombra. La respuesta general estuvo asociada a una estrategia de escape al sombreado, donde las plantas elongaron más los tallos y produjeron mayor área foliar en perjuicio de la biomasa radical y foliar. Sin embargo, se identificaron entradas cuya biomasa de tallo y raíz no sufrieron modificaciones significativas bajo sombra. No obstante, la conductividad estomática y la tasa fotosintética se vieron afectadas en todas las entradas en condiciones de sombra, independientemente de la biomasa relativa al testigo.

Influence of intra-row plant spacing, phosphorus application and growth stage on the forage, seed yields and quality of phasey bean (Macroptilium lathyroides) in subhumid area of Nigeria

Forage, seed yields and herbage chemical composition of phasey bean Macroptilium lathyroides) were investigated at 3 intra-row plant spacings (15, 30 and 45cm between plants; 50 cm between roms), 4 phosphorus (P) fertilizer application rates (O), 50, 100 and 750 kg/ha P) and 5 harvest stages (uncut control, 6, 9, 12 and 15 weeks post sowing) in two growing seasons at Shika in northern Nigeria. The least intra-row plant spacing (15cm) produced higher (p<0.01) total DM vield (1.50 t/ha) than wider spacings. The proportion of leaf was least (40 %) in the widest spacing compared with other spacings (59-62 %). The P-fertilized plots produced 58-60% more total DM vields than the unfertilized plots and total DM yields increased with advanced plant growth. The highest percentage (61-63) of leaf was recorded from 6 to 12 weeks post sowing. Nitrogen level in herbage increased (p<0.05) with increased intra-row plant spacing and P application. Phosphorus and Calcium. Levels in herbage did not respond to intra-row plant spacing but increased with P application. The Ca:P ratios at the harvest stages were between 1:1 and 6:1. The highest seed yields (198 and 188 kg/ha) were recorded respectiely in the least intra-row plant spacing and the application of 100 kg Piha. Supplementation of calves on grasses/cereal stovers with phasey bean hay in a sustainable crop livestock production systems is suggested.

Reproductive strategies of the Macroptilium lathyroides (Papilionoideae: Phaseoleae) explain the success of ruderal species in anthropized environments

Ruderal plants are important they are used for animal (e.g., beekeeping/pasture) and human food. Many of these plants present multiple reproductive strategies that ensure that they remain in disturbed environments. Therefore, we investigated the sexual reproduction and regeneration by regrowth of the forage ruderal Macroptillium lathyroides in an anthropized area to support management of this species after cutting or grazing and determine its requirements for seed production and conditions for commercial use. We assessed the occurrence of reproduction through regeneration and species dependence on pollinators. M. lathyroides has an axial underground system capable of regrowth but not propagation post-cut. Its flowers last about eight hours and are papilionate, asymmetrical, hermaphrodite, nectariferous, vinaceous and diurnal. They present secondary pollen that is transferred to the trichomes of the style. The species is self-compatible and presents spontaneous self-pollination. The small bee Exomalopsis cf. auropilosa, was the only pollinator since it activated the brush-type pollination mechanism while gathering nectar/pollen. The species depends on seeds to propagate or maintain a seed bank, since all plants do not regrow after cutting. Thus, sexual reproduction is necessary, but pollinators are not since it is not pollinator independent.

Intensidade de herbivoria na espécie Macroptilium lathyroides (Fabaceae)

RESUMO: As interações planta-animal, apresentam-se através de relações ditas desarmônicas ou antagonistas, e harmônicas ou de cooperação. Levando em consideração as relações antagonistas, a herbivoria é a mais importante, podendo afetar as folhas (folivoria), flores (florivoria), frutos (frugivoria) e sementes (granivoria). Fatores ambientais, dentre eles a densidade de plantas e interação com formigas, podem interferir diretamente nas taxas de herbivoria. O objetivo deste estudo foi investigar a ocorrência e intensidade da herbivoria em indivíduos isolados e adensados de Macroptilium lathyroides. A pesquisa foi realizada em uma área adjacente da Universidade Estadual de Alagoas, localizada no município de Palmeira dos Índios-AL, área com sinais de perturbação antrópica, a vegetação apresenta características de transição entre Mata Atlântica e Caatinga. A espécie estudada foi M. lathyroides uma herbácea que possui nectários extraflorais associados às suas estruturas reprodutivas. Foram avaliadas as taxas de folivoria, florivoria e frugivoria em 100 indivíduos ocorrentes em diferentes densidades, contabilizando o número total de folhas, flores e frutos com e sem sinais de herbivoria. Para análise estatística foi utilizado o teste chi quadrado com auxílio da ferramenta estatística BioEstat 5.0. A folivoria apresentou maiores taxas em indivíduos isolados, contudo a frugivoria não foi afetada. Na área de estudo, a folivoria foi afetada pela densidade, o que pode afetar a manutenção dessa espécie no local. PALAVRAS-CHAVE: Folivoria, florivoria, frugivoria, interação herbívoro-planta.

Chemical composition of Phasey Bean (Macroptilium Lathyroides (L.) Urb.)

The objective of the study was to determine the chimical composition of phasey bean throughout the productive cycle. The experiment was carried out in the municipality of Capão do Leão – RS, physiographic south coast region of Rio Grande do Sul. At 45 days after the emergence of the plants, the first cut of the forage evaluation was performed and, at intervals of 15 days, another nine cuts were made, all 5 cm from the soil. The treatments corresponded to different evaluation dates of Macroptilium in free growth in an experiment with ten treatments and three replicates in a completely randomized design. The variables studied were neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), crude protein (PB), total lipids (TL), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg). The results were submitted to analysis of variance and polynomial regression. All variables presented significance (P≤0.05) for cubic regressions, with mean values of: NDF = 58.15; FDA = 38.94; ADL = 9.15; PB = 11.59; TL = 1.18% e; P = 2.29; K = 10.19; Ca = 26.48 and Mg = 4.53 g / kg DM; similar to other hot-legged forage legumes. The bromatological quality of the Macroptilium lathyroides varied during the productive cycle, being directly influenced by the habit of indeterminate growth of the species. From the bromatological quality, the forage of the first growth of the Macroptilium lathyroides should be harvested up to 75 days after emergence, when the lower fiber and lignin contents associated with higher levels of crude protein, lipids, magnesium, and calcium.

Checklist of the Flora of Tutti Island, Khartoum Province, Sudan

The current study was aimed to inventory and document the flora of Tutti Island (the study area) During a field survey conducted between August 2016 to December 2018. A total of 155 species belong to 120 genera and 41 families were inventoried. A number of 135 species were Dicotyledonous belong to 115 genera and 37 families. However, 20 species were monocotyledonous belong to 17 genera and 4 families. The most representative families were Fabaceace (23 species), Poaceae (14 species), Amaranthaceae (13 species), Asteraceae (10 species), Malvaceae (9 species) and Euphorbiaceae (8 species) respectively. Herbs comprise the predominant type of growth habit (52.34%) followed by shrubs (30.87%), vines (10.06%) and trees (6.71%) respectively. Botanical names of species and families were updated. The study resulted in a number of species not previously recorded in the flora of the study area. The inventory led to a new generic record to the flora of Sudan; that is Macroptilium lathyroides (L.) Urb. Despite flora of the study area is rich, the study noticed that, there are some negative impact factors can affect this richness over time, these factors represented in human activities including overgrazing, agriculture and population expansion that beside to the annual flood.